SPC May 4, 2025 1730 UTC Day 2 Convective Outlook

4 months ago
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1215 PM CDT Sun May 04 2025 Valid 051200Z - 061200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS FAR SOUTHEAST NEW MEXICO INTO SOUTHWEST TEXAS... ...SUMMARY... Severe thunderstorms are expected from the southern High Plains into parts of central Texas Monday afternoon and evening. Scattered large to very large hail and severe winds are the primary threats, though a couple of tornadoes also are possible. Additional strong to severe storms are possible along the eastern Florida coast and from northeast North Carolina to the Lake Erie vicinity. ...Synopsis... A pair of upper cyclones, one over the Ohio Valley and the other across the Southwest, will pivot east on Monday. These systems will support a belt of enhanced mid/upper flow across the southern Rockies/High Plains and the Mid-Atlantic/Lower Great Lakes. At the surface, a cold front will stretch from the Mid-Atlantic south/southwest into north-central FL. Meanwhile, a dryline is forecast to develop across eastern NM and southwest TX, while a warm front lifts slowly northward across northwest and central TX. These features will focus potential for severe thunderstorms Monday afternoon into the evening/overnight. ...Southeast NM into Central TX... Southeasterly low-level flow will transport 60s F dewpoints northwest toward southeast NM into the Trans-Pecos vicinity ahead of a sharpening dryline. Strong heating along/just behind the dryline will foster moderate diurnal destabilization as deep-layer flow strengthens. Forecast hodographs initially will be elongated/straight through the afternoon and early evening. Splitting supercells produce large/very large hail are expected with initial convection. Furthermore, steep low-level lapse rates where stronger heating occurs also could support strong/severe gusts. During the evening, a low-level jet will increase, resulting in enlarged/curved low-level hodographs. Additional rounds of supercells may develop as the dryline begins to retreat and stronger ascent overspreads the region. This activity will continue to pose a significant hail risk with an increasing risk for a couple of tornadoes. As the upper low draws closer to the southern Rockies during the nighttime hours, weak cyclogenesis may occur over far southwest TX. Additional thunderstorm clusters, possibly growing upscale into an MCS propagating along the higher theta-e gradient across west-central to central TX is possible. It is uncertain how intense this convection may become given multiple rounds of convection across parts of the area earlier in the day, but some risk for damaging gusts and a tornado or two will persist. ...OK/TX Panhandle into Northeast NM/southeast CO... With northward extent across the southern High Plains, northward moisture return will remain muted, with dewpoints generally in the 40s to low 50s F forecast. Nevertheless, cooling aloft will support steepening midlevel lapse rates amid strengthening vertical shear. Isolated large hail and gusty winds may accompany thunderstorm activity north of the effective warm front in an upslope flow regime. ...Mid-Atlantic to Lower Great Lakes... Pockets of heating into the afternoon amid mid 50s to low 60s F dewpoints, and cold temperatures aloft will support modest destabilization (up to 1000 J/kg MLCAPE) across the region. Enhanced midlevel flow will support effective shear values to around 35-45 kt. This should support isolated organized updrafts, with stronger cells having potential for large hail and locally strong gusts during the afternoon and early evening. ...FL... A surface cold front will sag south through the period. Furthermore, an east coast sea breeze developing ahead of the cold front appears probable. Strong heating amid mid 60s F dewpoints will aid in moderate destabilization (MLCAPE up to 2000 J/kg). Cool temperatures aloft (-10 to -12 C at 500 mb) will support midlevel lapse rates near 7 C/km. While deep-layer flow will be somewhat weak through 700 mb, vertically veering wind profiles will support around 30 kt effective shear. Elongated/straight hodographs in conjunction with a favorable thermodynamic environment suggests isolated hail will be possible. Steep low-level lapse rates also will support strong gusts. ..Leitman.. 05/04/2025 Read more

SPC May 4, 2025 1730 UTC Day 2 Convective Outlook

4 months ago
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1215 PM CDT Sun May 04 2025 Valid 051200Z - 061200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS FAR SOUTHEAST NEW MEXICO INTO SOUTHWEST TEXAS... ...SUMMARY... Severe thunderstorms are expected from the southern High Plains into parts of central Texas Monday afternoon and evening. Scattered large to very large hail and severe winds are the primary threats, though a couple of tornadoes also are possible. Additional strong to severe storms are possible along the eastern Florida coast and from northeast North Carolina to the Lake Erie vicinity. ...Synopsis... A pair of upper cyclones, one over the Ohio Valley and the other across the Southwest, will pivot east on Monday. These systems will support a belt of enhanced mid/upper flow across the southern Rockies/High Plains and the Mid-Atlantic/Lower Great Lakes. At the surface, a cold front will stretch from the Mid-Atlantic south/southwest into north-central FL. Meanwhile, a dryline is forecast to develop across eastern NM and southwest TX, while a warm front lifts slowly northward across northwest and central TX. These features will focus potential for severe thunderstorms Monday afternoon into the evening/overnight. ...Southeast NM into Central TX... Southeasterly low-level flow will transport 60s F dewpoints northwest toward southeast NM into the Trans-Pecos vicinity ahead of a sharpening dryline. Strong heating along/just behind the dryline will foster moderate diurnal destabilization as deep-layer flow strengthens. Forecast hodographs initially will be elongated/straight through the afternoon and early evening. Splitting supercells produce large/very large hail are expected with initial convection. Furthermore, steep low-level lapse rates where stronger heating occurs also could support strong/severe gusts. During the evening, a low-level jet will increase, resulting in enlarged/curved low-level hodographs. Additional rounds of supercells may develop as the dryline begins to retreat and stronger ascent overspreads the region. This activity will continue to pose a significant hail risk with an increasing risk for a couple of tornadoes. As the upper low draws closer to the southern Rockies during the nighttime hours, weak cyclogenesis may occur over far southwest TX. Additional thunderstorm clusters, possibly growing upscale into an MCS propagating along the higher theta-e gradient across west-central to central TX is possible. It is uncertain how intense this convection may become given multiple rounds of convection across parts of the area earlier in the day, but some risk for damaging gusts and a tornado or two will persist. ...OK/TX Panhandle into Northeast NM/southeast CO... With northward extent across the southern High Plains, northward moisture return will remain muted, with dewpoints generally in the 40s to low 50s F forecast. Nevertheless, cooling aloft will support steepening midlevel lapse rates amid strengthening vertical shear. Isolated large hail and gusty winds may accompany thunderstorm activity north of the effective warm front in an upslope flow regime. ...Mid-Atlantic to Lower Great Lakes... Pockets of heating into the afternoon amid mid 50s to low 60s F dewpoints, and cold temperatures aloft will support modest destabilization (up to 1000 J/kg MLCAPE) across the region. Enhanced midlevel flow will support effective shear values to around 35-45 kt. This should support isolated organized updrafts, with stronger cells having potential for large hail and locally strong gusts during the afternoon and early evening. ...FL... A surface cold front will sag south through the period. Furthermore, an east coast sea breeze developing ahead of the cold front appears probable. Strong heating amid mid 60s F dewpoints will aid in moderate destabilization (MLCAPE up to 2000 J/kg). Cool temperatures aloft (-10 to -12 C at 500 mb) will support midlevel lapse rates near 7 C/km. While deep-layer flow will be somewhat weak through 700 mb, vertically veering wind profiles will support around 30 kt effective shear. Elongated/straight hodographs in conjunction with a favorable thermodynamic environment suggests isolated hail will be possible. Steep low-level lapse rates also will support strong gusts. ..Leitman.. 05/04/2025 Read more

SPC May 4, 2025 1730 UTC Day 2 Convective Outlook

4 months ago
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1215 PM CDT Sun May 04 2025 Valid 051200Z - 061200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS FAR SOUTHEAST NEW MEXICO INTO SOUTHWEST TEXAS... ...SUMMARY... Severe thunderstorms are expected from the southern High Plains into parts of central Texas Monday afternoon and evening. Scattered large to very large hail and severe winds are the primary threats, though a couple of tornadoes also are possible. Additional strong to severe storms are possible along the eastern Florida coast and from northeast North Carolina to the Lake Erie vicinity. ...Synopsis... A pair of upper cyclones, one over the Ohio Valley and the other across the Southwest, will pivot east on Monday. These systems will support a belt of enhanced mid/upper flow across the southern Rockies/High Plains and the Mid-Atlantic/Lower Great Lakes. At the surface, a cold front will stretch from the Mid-Atlantic south/southwest into north-central FL. Meanwhile, a dryline is forecast to develop across eastern NM and southwest TX, while a warm front lifts slowly northward across northwest and central TX. These features will focus potential for severe thunderstorms Monday afternoon into the evening/overnight. ...Southeast NM into Central TX... Southeasterly low-level flow will transport 60s F dewpoints northwest toward southeast NM into the Trans-Pecos vicinity ahead of a sharpening dryline. Strong heating along/just behind the dryline will foster moderate diurnal destabilization as deep-layer flow strengthens. Forecast hodographs initially will be elongated/straight through the afternoon and early evening. Splitting supercells produce large/very large hail are expected with initial convection. Furthermore, steep low-level lapse rates where stronger heating occurs also could support strong/severe gusts. During the evening, a low-level jet will increase, resulting in enlarged/curved low-level hodographs. Additional rounds of supercells may develop as the dryline begins to retreat and stronger ascent overspreads the region. This activity will continue to pose a significant hail risk with an increasing risk for a couple of tornadoes. As the upper low draws closer to the southern Rockies during the nighttime hours, weak cyclogenesis may occur over far southwest TX. Additional thunderstorm clusters, possibly growing upscale into an MCS propagating along the higher theta-e gradient across west-central to central TX is possible. It is uncertain how intense this convection may become given multiple rounds of convection across parts of the area earlier in the day, but some risk for damaging gusts and a tornado or two will persist. ...OK/TX Panhandle into Northeast NM/southeast CO... With northward extent across the southern High Plains, northward moisture return will remain muted, with dewpoints generally in the 40s to low 50s F forecast. Nevertheless, cooling aloft will support steepening midlevel lapse rates amid strengthening vertical shear. Isolated large hail and gusty winds may accompany thunderstorm activity north of the effective warm front in an upslope flow regime. ...Mid-Atlantic to Lower Great Lakes... Pockets of heating into the afternoon amid mid 50s to low 60s F dewpoints, and cold temperatures aloft will support modest destabilization (up to 1000 J/kg MLCAPE) across the region. Enhanced midlevel flow will support effective shear values to around 35-45 kt. This should support isolated organized updrafts, with stronger cells having potential for large hail and locally strong gusts during the afternoon and early evening. ...FL... A surface cold front will sag south through the period. Furthermore, an east coast sea breeze developing ahead of the cold front appears probable. Strong heating amid mid 60s F dewpoints will aid in moderate destabilization (MLCAPE up to 2000 J/kg). Cool temperatures aloft (-10 to -12 C at 500 mb) will support midlevel lapse rates near 7 C/km. While deep-layer flow will be somewhat weak through 700 mb, vertically veering wind profiles will support around 30 kt effective shear. Elongated/straight hodographs in conjunction with a favorable thermodynamic environment suggests isolated hail will be possible. Steep low-level lapse rates also will support strong gusts. ..Leitman.. 05/04/2025 Read more

SPC May 4, 2025 1730 UTC Day 2 Convective Outlook

4 months ago
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1215 PM CDT Sun May 04 2025 Valid 051200Z - 061200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS FAR SOUTHEAST NEW MEXICO INTO SOUTHWEST TEXAS... ...SUMMARY... Severe thunderstorms are expected from the southern High Plains into parts of central Texas Monday afternoon and evening. Scattered large to very large hail and severe winds are the primary threats, though a couple of tornadoes also are possible. Additional strong to severe storms are possible along the eastern Florida coast and from northeast North Carolina to the Lake Erie vicinity. ...Synopsis... A pair of upper cyclones, one over the Ohio Valley and the other across the Southwest, will pivot east on Monday. These systems will support a belt of enhanced mid/upper flow across the southern Rockies/High Plains and the Mid-Atlantic/Lower Great Lakes. At the surface, a cold front will stretch from the Mid-Atlantic south/southwest into north-central FL. Meanwhile, a dryline is forecast to develop across eastern NM and southwest TX, while a warm front lifts slowly northward across northwest and central TX. These features will focus potential for severe thunderstorms Monday afternoon into the evening/overnight. ...Southeast NM into Central TX... Southeasterly low-level flow will transport 60s F dewpoints northwest toward southeast NM into the Trans-Pecos vicinity ahead of a sharpening dryline. Strong heating along/just behind the dryline will foster moderate diurnal destabilization as deep-layer flow strengthens. Forecast hodographs initially will be elongated/straight through the afternoon and early evening. Splitting supercells produce large/very large hail are expected with initial convection. Furthermore, steep low-level lapse rates where stronger heating occurs also could support strong/severe gusts. During the evening, a low-level jet will increase, resulting in enlarged/curved low-level hodographs. Additional rounds of supercells may develop as the dryline begins to retreat and stronger ascent overspreads the region. This activity will continue to pose a significant hail risk with an increasing risk for a couple of tornadoes. As the upper low draws closer to the southern Rockies during the nighttime hours, weak cyclogenesis may occur over far southwest TX. Additional thunderstorm clusters, possibly growing upscale into an MCS propagating along the higher theta-e gradient across west-central to central TX is possible. It is uncertain how intense this convection may become given multiple rounds of convection across parts of the area earlier in the day, but some risk for damaging gusts and a tornado or two will persist. ...OK/TX Panhandle into Northeast NM/southeast CO... With northward extent across the southern High Plains, northward moisture return will remain muted, with dewpoints generally in the 40s to low 50s F forecast. Nevertheless, cooling aloft will support steepening midlevel lapse rates amid strengthening vertical shear. Isolated large hail and gusty winds may accompany thunderstorm activity north of the effective warm front in an upslope flow regime. ...Mid-Atlantic to Lower Great Lakes... Pockets of heating into the afternoon amid mid 50s to low 60s F dewpoints, and cold temperatures aloft will support modest destabilization (up to 1000 J/kg MLCAPE) across the region. Enhanced midlevel flow will support effective shear values to around 35-45 kt. This should support isolated organized updrafts, with stronger cells having potential for large hail and locally strong gusts during the afternoon and early evening. ...FL... A surface cold front will sag south through the period. Furthermore, an east coast sea breeze developing ahead of the cold front appears probable. Strong heating amid mid 60s F dewpoints will aid in moderate destabilization (MLCAPE up to 2000 J/kg). Cool temperatures aloft (-10 to -12 C at 500 mb) will support midlevel lapse rates near 7 C/km. While deep-layer flow will be somewhat weak through 700 mb, vertically veering wind profiles will support around 30 kt effective shear. Elongated/straight hodographs in conjunction with a favorable thermodynamic environment suggests isolated hail will be possible. Steep low-level lapse rates also will support strong gusts. ..Leitman.. 05/04/2025 Read more

SPC May 4, 2025 1730 UTC Day 2 Convective Outlook

4 months ago
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1215 PM CDT Sun May 04 2025 Valid 051200Z - 061200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS FAR SOUTHEAST NEW MEXICO INTO SOUTHWEST TEXAS... ...SUMMARY... Severe thunderstorms are expected from the southern High Plains into parts of central Texas Monday afternoon and evening. Scattered large to very large hail and severe winds are the primary threats, though a couple of tornadoes also are possible. Additional strong to severe storms are possible along the eastern Florida coast and from northeast North Carolina to the Lake Erie vicinity. ...Synopsis... A pair of upper cyclones, one over the Ohio Valley and the other across the Southwest, will pivot east on Monday. These systems will support a belt of enhanced mid/upper flow across the southern Rockies/High Plains and the Mid-Atlantic/Lower Great Lakes. At the surface, a cold front will stretch from the Mid-Atlantic south/southwest into north-central FL. Meanwhile, a dryline is forecast to develop across eastern NM and southwest TX, while a warm front lifts slowly northward across northwest and central TX. These features will focus potential for severe thunderstorms Monday afternoon into the evening/overnight. ...Southeast NM into Central TX... Southeasterly low-level flow will transport 60s F dewpoints northwest toward southeast NM into the Trans-Pecos vicinity ahead of a sharpening dryline. Strong heating along/just behind the dryline will foster moderate diurnal destabilization as deep-layer flow strengthens. Forecast hodographs initially will be elongated/straight through the afternoon and early evening. Splitting supercells produce large/very large hail are expected with initial convection. Furthermore, steep low-level lapse rates where stronger heating occurs also could support strong/severe gusts. During the evening, a low-level jet will increase, resulting in enlarged/curved low-level hodographs. Additional rounds of supercells may develop as the dryline begins to retreat and stronger ascent overspreads the region. This activity will continue to pose a significant hail risk with an increasing risk for a couple of tornadoes. As the upper low draws closer to the southern Rockies during the nighttime hours, weak cyclogenesis may occur over far southwest TX. Additional thunderstorm clusters, possibly growing upscale into an MCS propagating along the higher theta-e gradient across west-central to central TX is possible. It is uncertain how intense this convection may become given multiple rounds of convection across parts of the area earlier in the day, but some risk for damaging gusts and a tornado or two will persist. ...OK/TX Panhandle into Northeast NM/southeast CO... With northward extent across the southern High Plains, northward moisture return will remain muted, with dewpoints generally in the 40s to low 50s F forecast. Nevertheless, cooling aloft will support steepening midlevel lapse rates amid strengthening vertical shear. Isolated large hail and gusty winds may accompany thunderstorm activity north of the effective warm front in an upslope flow regime. ...Mid-Atlantic to Lower Great Lakes... Pockets of heating into the afternoon amid mid 50s to low 60s F dewpoints, and cold temperatures aloft will support modest destabilization (up to 1000 J/kg MLCAPE) across the region. Enhanced midlevel flow will support effective shear values to around 35-45 kt. This should support isolated organized updrafts, with stronger cells having potential for large hail and locally strong gusts during the afternoon and early evening. ...FL... A surface cold front will sag south through the period. Furthermore, an east coast sea breeze developing ahead of the cold front appears probable. Strong heating amid mid 60s F dewpoints will aid in moderate destabilization (MLCAPE up to 2000 J/kg). Cool temperatures aloft (-10 to -12 C at 500 mb) will support midlevel lapse rates near 7 C/km. While deep-layer flow will be somewhat weak through 700 mb, vertically veering wind profiles will support around 30 kt effective shear. Elongated/straight hodographs in conjunction with a favorable thermodynamic environment suggests isolated hail will be possible. Steep low-level lapse rates also will support strong gusts. ..Leitman.. 05/04/2025 Read more

SPC May 4, 2025 1630 UTC Day 1 Convective Outlook

4 months ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1125 AM CDT Sun May 04 2025 Valid 041630Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF EASTERN NEW MEXICO AND WEST TEXAS... ...SUMMARY... Scattered severe thunderstorms are expected across parts of eastern New Mexico and west Texas this afternoon and evening. Large to very large hail, isolated severe wind gusts, and possibly a tornado or two may occur. ...New Mexico and West Texas... Large-scale ascent will increase this afternoon across NM and the southern High Plains as strong difluence aloft associated with an upper low over northwest Mexico and the Southwest moves eastward. Steep lapse rates aloft atop modest low-level moisture will act in tandem with daytime heating to foster up to 1000-1250 J/kg of MLCAPE across eastern NM and far west TX by mid afternoon. While low-level southeasterly flow will initially be modest, various RAP/NAM forecast soundings show substantial veering and some strengthening with height at mid/upper levels. Resultant long/straight hodographs aloft and strong deep-layer shear will likely support a few supercells with an attendant threat for large to very large hail (up to 1.5-2.5 inches in diameter). Isolated severe wind gusts may also occur as this convection spreads slowly eastward across eastern NM into parts of west TX through the evening. Although low-level moisture will remain modest, a southeasterly low-level jet is also expected to gradually strengthen this evening, which should support enough 0-1 km SRH for a tornado or two with any sustained supercell. These thunderstorms will eventually weaken with eastward extent into west TX as MLCIN gradually increases by mid/late evening. ...Upper Ohio Valley/Mid-Atlantic to the Carolinas... An expansive closed mid/upper-level low will remain centered over the OH/TN Valleys today. A belt of stronger south-southwesterly mid-level winds will overspread parts of the upper OH Valley and southern Mid-Atlantic through this evening. This enhanced flow along with upper-level difluence should provide sufficient large-scale ascent for isolated to scattered convection this afternoon across parts of OH into WV and western PA. Low-level moisture will remain somewhat limited across this area, with surface dewpoints generally in the low to mid 50s. Even with filtered daytime heating, poor lapse rates aloft should keep any more than weak instability from developing. Various RAP forecast soundings across this region also show flow backing with height aloft, which lends considerable uncertainty regarding convective organization. While an isolated damaging wind/hail threat may exist, the overall environment should keep the severe threat fairly marginal. A somewhat separate area of convection may develop this afternoon across eastern NC into VA, generally along/ahead of a weak surface front. While these thunderstorms will have access to greater low-level moisture, both instability and deep-layer shear are expected to remain modest. Still, some risk for damaging winds and hail should exist with any cells or clusters that can develop, before this activity gradually weakens through the evening with the loss of daytime heating. ...Florida... Scattered showers and thunderstorms are ongoing across parts of the southern/central FL Peninsula. A subtropical upper-level jet should continue to aid thunderstorm development across the FL Peninsula through the afternoon. But, persistent cloud cover and poor lapse rates aloft noted on area 12Z soundings may hinder destabilization to some degree. Even so, a rather moist low-level airmass exists along/south of a front over north FL/far southeast GA, and even modest further heating should support sufficient instability for surface-based convection. With weak low-level flow gradually veering to westerly and strengthening at mid/upper levels, this activity should have enough deep-layer shear for modest updraft organization. Thunderstorms may preferentially form on/near the Atlantic Coast sea breeze this afternoon while posing an isolated threat for severe hail, damaging winds, and perhaps a brief tornado. ...Eastern Idaho into Southern Montana... As a mid-level trough moves eastward over western Canada and the northern Rockies, scattered thunderstorms should develop this afternoon and evening across eastern Idaho into southwest Montana. This region will have steep mid-level lapse rates and cool temperatures aloft associated with the shortwave trough. Deep-layer shear is expected to remain modest, but a couple of stronger cores with small hail and gusty winds could still occur. ..Gleason/Squitieri.. 05/04/2025 Read more

SPC May 4, 2025 1630 UTC Day 1 Convective Outlook

4 months ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1125 AM CDT Sun May 04 2025 Valid 041630Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF EASTERN NEW MEXICO AND WEST TEXAS... ...SUMMARY... Scattered severe thunderstorms are expected across parts of eastern New Mexico and west Texas this afternoon and evening. Large to very large hail, isolated severe wind gusts, and possibly a tornado or two may occur. ...New Mexico and West Texas... Large-scale ascent will increase this afternoon across NM and the southern High Plains as strong difluence aloft associated with an upper low over northwest Mexico and the Southwest moves eastward. Steep lapse rates aloft atop modest low-level moisture will act in tandem with daytime heating to foster up to 1000-1250 J/kg of MLCAPE across eastern NM and far west TX by mid afternoon. While low-level southeasterly flow will initially be modest, various RAP/NAM forecast soundings show substantial veering and some strengthening with height at mid/upper levels. Resultant long/straight hodographs aloft and strong deep-layer shear will likely support a few supercells with an attendant threat for large to very large hail (up to 1.5-2.5 inches in diameter). Isolated severe wind gusts may also occur as this convection spreads slowly eastward across eastern NM into parts of west TX through the evening. Although low-level moisture will remain modest, a southeasterly low-level jet is also expected to gradually strengthen this evening, which should support enough 0-1 km SRH for a tornado or two with any sustained supercell. These thunderstorms will eventually weaken with eastward extent into west TX as MLCIN gradually increases by mid/late evening. ...Upper Ohio Valley/Mid-Atlantic to the Carolinas... An expansive closed mid/upper-level low will remain centered over the OH/TN Valleys today. A belt of stronger south-southwesterly mid-level winds will overspread parts of the upper OH Valley and southern Mid-Atlantic through this evening. This enhanced flow along with upper-level difluence should provide sufficient large-scale ascent for isolated to scattered convection this afternoon across parts of OH into WV and western PA. Low-level moisture will remain somewhat limited across this area, with surface dewpoints generally in the low to mid 50s. Even with filtered daytime heating, poor lapse rates aloft should keep any more than weak instability from developing. Various RAP forecast soundings across this region also show flow backing with height aloft, which lends considerable uncertainty regarding convective organization. While an isolated damaging wind/hail threat may exist, the overall environment should keep the severe threat fairly marginal. A somewhat separate area of convection may develop this afternoon across eastern NC into VA, generally along/ahead of a weak surface front. While these thunderstorms will have access to greater low-level moisture, both instability and deep-layer shear are expected to remain modest. Still, some risk for damaging winds and hail should exist with any cells or clusters that can develop, before this activity gradually weakens through the evening with the loss of daytime heating. ...Florida... Scattered showers and thunderstorms are ongoing across parts of the southern/central FL Peninsula. A subtropical upper-level jet should continue to aid thunderstorm development across the FL Peninsula through the afternoon. But, persistent cloud cover and poor lapse rates aloft noted on area 12Z soundings may hinder destabilization to some degree. Even so, a rather moist low-level airmass exists along/south of a front over north FL/far southeast GA, and even modest further heating should support sufficient instability for surface-based convection. With weak low-level flow gradually veering to westerly and strengthening at mid/upper levels, this activity should have enough deep-layer shear for modest updraft organization. Thunderstorms may preferentially form on/near the Atlantic Coast sea breeze this afternoon while posing an isolated threat for severe hail, damaging winds, and perhaps a brief tornado. ...Eastern Idaho into Southern Montana... As a mid-level trough moves eastward over western Canada and the northern Rockies, scattered thunderstorms should develop this afternoon and evening across eastern Idaho into southwest Montana. This region will have steep mid-level lapse rates and cool temperatures aloft associated with the shortwave trough. Deep-layer shear is expected to remain modest, but a couple of stronger cores with small hail and gusty winds could still occur. ..Gleason/Squitieri.. 05/04/2025 Read more

SPC May 4, 2025 1630 UTC Day 1 Convective Outlook

4 months ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1125 AM CDT Sun May 04 2025 Valid 041630Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF EASTERN NEW MEXICO AND WEST TEXAS... ...SUMMARY... Scattered severe thunderstorms are expected across parts of eastern New Mexico and west Texas this afternoon and evening. Large to very large hail, isolated severe wind gusts, and possibly a tornado or two may occur. ...New Mexico and West Texas... Large-scale ascent will increase this afternoon across NM and the southern High Plains as strong difluence aloft associated with an upper low over northwest Mexico and the Southwest moves eastward. Steep lapse rates aloft atop modest low-level moisture will act in tandem with daytime heating to foster up to 1000-1250 J/kg of MLCAPE across eastern NM and far west TX by mid afternoon. While low-level southeasterly flow will initially be modest, various RAP/NAM forecast soundings show substantial veering and some strengthening with height at mid/upper levels. Resultant long/straight hodographs aloft and strong deep-layer shear will likely support a few supercells with an attendant threat for large to very large hail (up to 1.5-2.5 inches in diameter). Isolated severe wind gusts may also occur as this convection spreads slowly eastward across eastern NM into parts of west TX through the evening. Although low-level moisture will remain modest, a southeasterly low-level jet is also expected to gradually strengthen this evening, which should support enough 0-1 km SRH for a tornado or two with any sustained supercell. These thunderstorms will eventually weaken with eastward extent into west TX as MLCIN gradually increases by mid/late evening. ...Upper Ohio Valley/Mid-Atlantic to the Carolinas... An expansive closed mid/upper-level low will remain centered over the OH/TN Valleys today. A belt of stronger south-southwesterly mid-level winds will overspread parts of the upper OH Valley and southern Mid-Atlantic through this evening. This enhanced flow along with upper-level difluence should provide sufficient large-scale ascent for isolated to scattered convection this afternoon across parts of OH into WV and western PA. Low-level moisture will remain somewhat limited across this area, with surface dewpoints generally in the low to mid 50s. Even with filtered daytime heating, poor lapse rates aloft should keep any more than weak instability from developing. Various RAP forecast soundings across this region also show flow backing with height aloft, which lends considerable uncertainty regarding convective organization. While an isolated damaging wind/hail threat may exist, the overall environment should keep the severe threat fairly marginal. A somewhat separate area of convection may develop this afternoon across eastern NC into VA, generally along/ahead of a weak surface front. While these thunderstorms will have access to greater low-level moisture, both instability and deep-layer shear are expected to remain modest. Still, some risk for damaging winds and hail should exist with any cells or clusters that can develop, before this activity gradually weakens through the evening with the loss of daytime heating. ...Florida... Scattered showers and thunderstorms are ongoing across parts of the southern/central FL Peninsula. A subtropical upper-level jet should continue to aid thunderstorm development across the FL Peninsula through the afternoon. But, persistent cloud cover and poor lapse rates aloft noted on area 12Z soundings may hinder destabilization to some degree. Even so, a rather moist low-level airmass exists along/south of a front over north FL/far southeast GA, and even modest further heating should support sufficient instability for surface-based convection. With weak low-level flow gradually veering to westerly and strengthening at mid/upper levels, this activity should have enough deep-layer shear for modest updraft organization. Thunderstorms may preferentially form on/near the Atlantic Coast sea breeze this afternoon while posing an isolated threat for severe hail, damaging winds, and perhaps a brief tornado. ...Eastern Idaho into Southern Montana... As a mid-level trough moves eastward over western Canada and the northern Rockies, scattered thunderstorms should develop this afternoon and evening across eastern Idaho into southwest Montana. This region will have steep mid-level lapse rates and cool temperatures aloft associated with the shortwave trough. Deep-layer shear is expected to remain modest, but a couple of stronger cores with small hail and gusty winds could still occur. ..Gleason/Squitieri.. 05/04/2025 Read more

SPC May 4, 2025 1630 UTC Day 1 Convective Outlook

4 months ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1125 AM CDT Sun May 04 2025 Valid 041630Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF EASTERN NEW MEXICO AND WEST TEXAS... ...SUMMARY... Scattered severe thunderstorms are expected across parts of eastern New Mexico and west Texas this afternoon and evening. Large to very large hail, isolated severe wind gusts, and possibly a tornado or two may occur. ...New Mexico and West Texas... Large-scale ascent will increase this afternoon across NM and the southern High Plains as strong difluence aloft associated with an upper low over northwest Mexico and the Southwest moves eastward. Steep lapse rates aloft atop modest low-level moisture will act in tandem with daytime heating to foster up to 1000-1250 J/kg of MLCAPE across eastern NM and far west TX by mid afternoon. While low-level southeasterly flow will initially be modest, various RAP/NAM forecast soundings show substantial veering and some strengthening with height at mid/upper levels. Resultant long/straight hodographs aloft and strong deep-layer shear will likely support a few supercells with an attendant threat for large to very large hail (up to 1.5-2.5 inches in diameter). Isolated severe wind gusts may also occur as this convection spreads slowly eastward across eastern NM into parts of west TX through the evening. Although low-level moisture will remain modest, a southeasterly low-level jet is also expected to gradually strengthen this evening, which should support enough 0-1 km SRH for a tornado or two with any sustained supercell. These thunderstorms will eventually weaken with eastward extent into west TX as MLCIN gradually increases by mid/late evening. ...Upper Ohio Valley/Mid-Atlantic to the Carolinas... An expansive closed mid/upper-level low will remain centered over the OH/TN Valleys today. A belt of stronger south-southwesterly mid-level winds will overspread parts of the upper OH Valley and southern Mid-Atlantic through this evening. This enhanced flow along with upper-level difluence should provide sufficient large-scale ascent for isolated to scattered convection this afternoon across parts of OH into WV and western PA. Low-level moisture will remain somewhat limited across this area, with surface dewpoints generally in the low to mid 50s. Even with filtered daytime heating, poor lapse rates aloft should keep any more than weak instability from developing. Various RAP forecast soundings across this region also show flow backing with height aloft, which lends considerable uncertainty regarding convective organization. While an isolated damaging wind/hail threat may exist, the overall environment should keep the severe threat fairly marginal. A somewhat separate area of convection may develop this afternoon across eastern NC into VA, generally along/ahead of a weak surface front. While these thunderstorms will have access to greater low-level moisture, both instability and deep-layer shear are expected to remain modest. Still, some risk for damaging winds and hail should exist with any cells or clusters that can develop, before this activity gradually weakens through the evening with the loss of daytime heating. ...Florida... Scattered showers and thunderstorms are ongoing across parts of the southern/central FL Peninsula. A subtropical upper-level jet should continue to aid thunderstorm development across the FL Peninsula through the afternoon. But, persistent cloud cover and poor lapse rates aloft noted on area 12Z soundings may hinder destabilization to some degree. Even so, a rather moist low-level airmass exists along/south of a front over north FL/far southeast GA, and even modest further heating should support sufficient instability for surface-based convection. With weak low-level flow gradually veering to westerly and strengthening at mid/upper levels, this activity should have enough deep-layer shear for modest updraft organization. Thunderstorms may preferentially form on/near the Atlantic Coast sea breeze this afternoon while posing an isolated threat for severe hail, damaging winds, and perhaps a brief tornado. ...Eastern Idaho into Southern Montana... As a mid-level trough moves eastward over western Canada and the northern Rockies, scattered thunderstorms should develop this afternoon and evening across eastern Idaho into southwest Montana. This region will have steep mid-level lapse rates and cool temperatures aloft associated with the shortwave trough. Deep-layer shear is expected to remain modest, but a couple of stronger cores with small hail and gusty winds could still occur. ..Gleason/Squitieri.. 05/04/2025 Read more

SPC May 4, 2025 1630 UTC Day 1 Convective Outlook

4 months ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1125 AM CDT Sun May 04 2025 Valid 041630Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF EASTERN NEW MEXICO AND WEST TEXAS... ...SUMMARY... Scattered severe thunderstorms are expected across parts of eastern New Mexico and west Texas this afternoon and evening. Large to very large hail, isolated severe wind gusts, and possibly a tornado or two may occur. ...New Mexico and West Texas... Large-scale ascent will increase this afternoon across NM and the southern High Plains as strong difluence aloft associated with an upper low over northwest Mexico and the Southwest moves eastward. Steep lapse rates aloft atop modest low-level moisture will act in tandem with daytime heating to foster up to 1000-1250 J/kg of MLCAPE across eastern NM and far west TX by mid afternoon. While low-level southeasterly flow will initially be modest, various RAP/NAM forecast soundings show substantial veering and some strengthening with height at mid/upper levels. Resultant long/straight hodographs aloft and strong deep-layer shear will likely support a few supercells with an attendant threat for large to very large hail (up to 1.5-2.5 inches in diameter). Isolated severe wind gusts may also occur as this convection spreads slowly eastward across eastern NM into parts of west TX through the evening. Although low-level moisture will remain modest, a southeasterly low-level jet is also expected to gradually strengthen this evening, which should support enough 0-1 km SRH for a tornado or two with any sustained supercell. These thunderstorms will eventually weaken with eastward extent into west TX as MLCIN gradually increases by mid/late evening. ...Upper Ohio Valley/Mid-Atlantic to the Carolinas... An expansive closed mid/upper-level low will remain centered over the OH/TN Valleys today. A belt of stronger south-southwesterly mid-level winds will overspread parts of the upper OH Valley and southern Mid-Atlantic through this evening. This enhanced flow along with upper-level difluence should provide sufficient large-scale ascent for isolated to scattered convection this afternoon across parts of OH into WV and western PA. Low-level moisture will remain somewhat limited across this area, with surface dewpoints generally in the low to mid 50s. Even with filtered daytime heating, poor lapse rates aloft should keep any more than weak instability from developing. Various RAP forecast soundings across this region also show flow backing with height aloft, which lends considerable uncertainty regarding convective organization. While an isolated damaging wind/hail threat may exist, the overall environment should keep the severe threat fairly marginal. A somewhat separate area of convection may develop this afternoon across eastern NC into VA, generally along/ahead of a weak surface front. While these thunderstorms will have access to greater low-level moisture, both instability and deep-layer shear are expected to remain modest. Still, some risk for damaging winds and hail should exist with any cells or clusters that can develop, before this activity gradually weakens through the evening with the loss of daytime heating. ...Florida... Scattered showers and thunderstorms are ongoing across parts of the southern/central FL Peninsula. A subtropical upper-level jet should continue to aid thunderstorm development across the FL Peninsula through the afternoon. But, persistent cloud cover and poor lapse rates aloft noted on area 12Z soundings may hinder destabilization to some degree. Even so, a rather moist low-level airmass exists along/south of a front over north FL/far southeast GA, and even modest further heating should support sufficient instability for surface-based convection. With weak low-level flow gradually veering to westerly and strengthening at mid/upper levels, this activity should have enough deep-layer shear for modest updraft organization. Thunderstorms may preferentially form on/near the Atlantic Coast sea breeze this afternoon while posing an isolated threat for severe hail, damaging winds, and perhaps a brief tornado. ...Eastern Idaho into Southern Montana... As a mid-level trough moves eastward over western Canada and the northern Rockies, scattered thunderstorms should develop this afternoon and evening across eastern Idaho into southwest Montana. This region will have steep mid-level lapse rates and cool temperatures aloft associated with the shortwave trough. Deep-layer shear is expected to remain modest, but a couple of stronger cores with small hail and gusty winds could still occur. ..Gleason/Squitieri.. 05/04/2025 Read more

SPC May 4, 2025 1630 UTC Day 1 Convective Outlook

4 months ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1125 AM CDT Sun May 04 2025 Valid 041630Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF EASTERN NEW MEXICO AND WEST TEXAS... ...SUMMARY... Scattered severe thunderstorms are expected across parts of eastern New Mexico and west Texas this afternoon and evening. Large to very large hail, isolated severe wind gusts, and possibly a tornado or two may occur. ...New Mexico and West Texas... Large-scale ascent will increase this afternoon across NM and the southern High Plains as strong difluence aloft associated with an upper low over northwest Mexico and the Southwest moves eastward. Steep lapse rates aloft atop modest low-level moisture will act in tandem with daytime heating to foster up to 1000-1250 J/kg of MLCAPE across eastern NM and far west TX by mid afternoon. While low-level southeasterly flow will initially be modest, various RAP/NAM forecast soundings show substantial veering and some strengthening with height at mid/upper levels. Resultant long/straight hodographs aloft and strong deep-layer shear will likely support a few supercells with an attendant threat for large to very large hail (up to 1.5-2.5 inches in diameter). Isolated severe wind gusts may also occur as this convection spreads slowly eastward across eastern NM into parts of west TX through the evening. Although low-level moisture will remain modest, a southeasterly low-level jet is also expected to gradually strengthen this evening, which should support enough 0-1 km SRH for a tornado or two with any sustained supercell. These thunderstorms will eventually weaken with eastward extent into west TX as MLCIN gradually increases by mid/late evening. ...Upper Ohio Valley/Mid-Atlantic to the Carolinas... An expansive closed mid/upper-level low will remain centered over the OH/TN Valleys today. A belt of stronger south-southwesterly mid-level winds will overspread parts of the upper OH Valley and southern Mid-Atlantic through this evening. This enhanced flow along with upper-level difluence should provide sufficient large-scale ascent for isolated to scattered convection this afternoon across parts of OH into WV and western PA. Low-level moisture will remain somewhat limited across this area, with surface dewpoints generally in the low to mid 50s. Even with filtered daytime heating, poor lapse rates aloft should keep any more than weak instability from developing. Various RAP forecast soundings across this region also show flow backing with height aloft, which lends considerable uncertainty regarding convective organization. While an isolated damaging wind/hail threat may exist, the overall environment should keep the severe threat fairly marginal. A somewhat separate area of convection may develop this afternoon across eastern NC into VA, generally along/ahead of a weak surface front. While these thunderstorms will have access to greater low-level moisture, both instability and deep-layer shear are expected to remain modest. Still, some risk for damaging winds and hail should exist with any cells or clusters that can develop, before this activity gradually weakens through the evening with the loss of daytime heating. ...Florida... Scattered showers and thunderstorms are ongoing across parts of the southern/central FL Peninsula. A subtropical upper-level jet should continue to aid thunderstorm development across the FL Peninsula through the afternoon. But, persistent cloud cover and poor lapse rates aloft noted on area 12Z soundings may hinder destabilization to some degree. Even so, a rather moist low-level airmass exists along/south of a front over north FL/far southeast GA, and even modest further heating should support sufficient instability for surface-based convection. With weak low-level flow gradually veering to westerly and strengthening at mid/upper levels, this activity should have enough deep-layer shear for modest updraft organization. Thunderstorms may preferentially form on/near the Atlantic Coast sea breeze this afternoon while posing an isolated threat for severe hail, damaging winds, and perhaps a brief tornado. ...Eastern Idaho into Southern Montana... As a mid-level trough moves eastward over western Canada and the northern Rockies, scattered thunderstorms should develop this afternoon and evening across eastern Idaho into southwest Montana. This region will have steep mid-level lapse rates and cool temperatures aloft associated with the shortwave trough. Deep-layer shear is expected to remain modest, but a couple of stronger cores with small hail and gusty winds could still occur. ..Gleason/Squitieri.. 05/04/2025 Read more

SPC May 4, 2025 1630 UTC Day 1 Convective Outlook

4 months ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1125 AM CDT Sun May 04 2025 Valid 041630Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF EASTERN NEW MEXICO AND WEST TEXAS... ...SUMMARY... Scattered severe thunderstorms are expected across parts of eastern New Mexico and west Texas this afternoon and evening. Large to very large hail, isolated severe wind gusts, and possibly a tornado or two may occur. ...New Mexico and West Texas... Large-scale ascent will increase this afternoon across NM and the southern High Plains as strong difluence aloft associated with an upper low over northwest Mexico and the Southwest moves eastward. Steep lapse rates aloft atop modest low-level moisture will act in tandem with daytime heating to foster up to 1000-1250 J/kg of MLCAPE across eastern NM and far west TX by mid afternoon. While low-level southeasterly flow will initially be modest, various RAP/NAM forecast soundings show substantial veering and some strengthening with height at mid/upper levels. Resultant long/straight hodographs aloft and strong deep-layer shear will likely support a few supercells with an attendant threat for large to very large hail (up to 1.5-2.5 inches in diameter). Isolated severe wind gusts may also occur as this convection spreads slowly eastward across eastern NM into parts of west TX through the evening. Although low-level moisture will remain modest, a southeasterly low-level jet is also expected to gradually strengthen this evening, which should support enough 0-1 km SRH for a tornado or two with any sustained supercell. These thunderstorms will eventually weaken with eastward extent into west TX as MLCIN gradually increases by mid/late evening. ...Upper Ohio Valley/Mid-Atlantic to the Carolinas... An expansive closed mid/upper-level low will remain centered over the OH/TN Valleys today. A belt of stronger south-southwesterly mid-level winds will overspread parts of the upper OH Valley and southern Mid-Atlantic through this evening. This enhanced flow along with upper-level difluence should provide sufficient large-scale ascent for isolated to scattered convection this afternoon across parts of OH into WV and western PA. Low-level moisture will remain somewhat limited across this area, with surface dewpoints generally in the low to mid 50s. Even with filtered daytime heating, poor lapse rates aloft should keep any more than weak instability from developing. Various RAP forecast soundings across this region also show flow backing with height aloft, which lends considerable uncertainty regarding convective organization. While an isolated damaging wind/hail threat may exist, the overall environment should keep the severe threat fairly marginal. A somewhat separate area of convection may develop this afternoon across eastern NC into VA, generally along/ahead of a weak surface front. While these thunderstorms will have access to greater low-level moisture, both instability and deep-layer shear are expected to remain modest. Still, some risk for damaging winds and hail should exist with any cells or clusters that can develop, before this activity gradually weakens through the evening with the loss of daytime heating. ...Florida... Scattered showers and thunderstorms are ongoing across parts of the southern/central FL Peninsula. A subtropical upper-level jet should continue to aid thunderstorm development across the FL Peninsula through the afternoon. But, persistent cloud cover and poor lapse rates aloft noted on area 12Z soundings may hinder destabilization to some degree. Even so, a rather moist low-level airmass exists along/south of a front over north FL/far southeast GA, and even modest further heating should support sufficient instability for surface-based convection. With weak low-level flow gradually veering to westerly and strengthening at mid/upper levels, this activity should have enough deep-layer shear for modest updraft organization. Thunderstorms may preferentially form on/near the Atlantic Coast sea breeze this afternoon while posing an isolated threat for severe hail, damaging winds, and perhaps a brief tornado. ...Eastern Idaho into Southern Montana... As a mid-level trough moves eastward over western Canada and the northern Rockies, scattered thunderstorms should develop this afternoon and evening across eastern Idaho into southwest Montana. This region will have steep mid-level lapse rates and cool temperatures aloft associated with the shortwave trough. Deep-layer shear is expected to remain modest, but a couple of stronger cores with small hail and gusty winds could still occur. ..Gleason/Squitieri.. 05/04/2025 Read more

SPC May 4, 2025 1630 UTC Day 1 Convective Outlook

4 months ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1125 AM CDT Sun May 04 2025 Valid 041630Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF EASTERN NEW MEXICO AND WEST TEXAS... ...SUMMARY... Scattered severe thunderstorms are expected across parts of eastern New Mexico and west Texas this afternoon and evening. Large to very large hail, isolated severe wind gusts, and possibly a tornado or two may occur. ...New Mexico and West Texas... Large-scale ascent will increase this afternoon across NM and the southern High Plains as strong difluence aloft associated with an upper low over northwest Mexico and the Southwest moves eastward. Steep lapse rates aloft atop modest low-level moisture will act in tandem with daytime heating to foster up to 1000-1250 J/kg of MLCAPE across eastern NM and far west TX by mid afternoon. While low-level southeasterly flow will initially be modest, various RAP/NAM forecast soundings show substantial veering and some strengthening with height at mid/upper levels. Resultant long/straight hodographs aloft and strong deep-layer shear will likely support a few supercells with an attendant threat for large to very large hail (up to 1.5-2.5 inches in diameter). Isolated severe wind gusts may also occur as this convection spreads slowly eastward across eastern NM into parts of west TX through the evening. Although low-level moisture will remain modest, a southeasterly low-level jet is also expected to gradually strengthen this evening, which should support enough 0-1 km SRH for a tornado or two with any sustained supercell. These thunderstorms will eventually weaken with eastward extent into west TX as MLCIN gradually increases by mid/late evening. ...Upper Ohio Valley/Mid-Atlantic to the Carolinas... An expansive closed mid/upper-level low will remain centered over the OH/TN Valleys today. A belt of stronger south-southwesterly mid-level winds will overspread parts of the upper OH Valley and southern Mid-Atlantic through this evening. This enhanced flow along with upper-level difluence should provide sufficient large-scale ascent for isolated to scattered convection this afternoon across parts of OH into WV and western PA. Low-level moisture will remain somewhat limited across this area, with surface dewpoints generally in the low to mid 50s. Even with filtered daytime heating, poor lapse rates aloft should keep any more than weak instability from developing. Various RAP forecast soundings across this region also show flow backing with height aloft, which lends considerable uncertainty regarding convective organization. While an isolated damaging wind/hail threat may exist, the overall environment should keep the severe threat fairly marginal. A somewhat separate area of convection may develop this afternoon across eastern NC into VA, generally along/ahead of a weak surface front. While these thunderstorms will have access to greater low-level moisture, both instability and deep-layer shear are expected to remain modest. Still, some risk for damaging winds and hail should exist with any cells or clusters that can develop, before this activity gradually weakens through the evening with the loss of daytime heating. ...Florida... Scattered showers and thunderstorms are ongoing across parts of the southern/central FL Peninsula. A subtropical upper-level jet should continue to aid thunderstorm development across the FL Peninsula through the afternoon. But, persistent cloud cover and poor lapse rates aloft noted on area 12Z soundings may hinder destabilization to some degree. Even so, a rather moist low-level airmass exists along/south of a front over north FL/far southeast GA, and even modest further heating should support sufficient instability for surface-based convection. With weak low-level flow gradually veering to westerly and strengthening at mid/upper levels, this activity should have enough deep-layer shear for modest updraft organization. Thunderstorms may preferentially form on/near the Atlantic Coast sea breeze this afternoon while posing an isolated threat for severe hail, damaging winds, and perhaps a brief tornado. ...Eastern Idaho into Southern Montana... As a mid-level trough moves eastward over western Canada and the northern Rockies, scattered thunderstorms should develop this afternoon and evening across eastern Idaho into southwest Montana. This region will have steep mid-level lapse rates and cool temperatures aloft associated with the shortwave trough. Deep-layer shear is expected to remain modest, but a couple of stronger cores with small hail and gusty winds could still occur. ..Gleason/Squitieri.. 05/04/2025 Read more

SPC May 4, 2025 1630 UTC Day 1 Convective Outlook

4 months ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1125 AM CDT Sun May 04 2025 Valid 041630Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF EASTERN NEW MEXICO AND WEST TEXAS... ...SUMMARY... Scattered severe thunderstorms are expected across parts of eastern New Mexico and west Texas this afternoon and evening. Large to very large hail, isolated severe wind gusts, and possibly a tornado or two may occur. ...New Mexico and West Texas... Large-scale ascent will increase this afternoon across NM and the southern High Plains as strong difluence aloft associated with an upper low over northwest Mexico and the Southwest moves eastward. Steep lapse rates aloft atop modest low-level moisture will act in tandem with daytime heating to foster up to 1000-1250 J/kg of MLCAPE across eastern NM and far west TX by mid afternoon. While low-level southeasterly flow will initially be modest, various RAP/NAM forecast soundings show substantial veering and some strengthening with height at mid/upper levels. Resultant long/straight hodographs aloft and strong deep-layer shear will likely support a few supercells with an attendant threat for large to very large hail (up to 1.5-2.5 inches in diameter). Isolated severe wind gusts may also occur as this convection spreads slowly eastward across eastern NM into parts of west TX through the evening. Although low-level moisture will remain modest, a southeasterly low-level jet is also expected to gradually strengthen this evening, which should support enough 0-1 km SRH for a tornado or two with any sustained supercell. These thunderstorms will eventually weaken with eastward extent into west TX as MLCIN gradually increases by mid/late evening. ...Upper Ohio Valley/Mid-Atlantic to the Carolinas... An expansive closed mid/upper-level low will remain centered over the OH/TN Valleys today. A belt of stronger south-southwesterly mid-level winds will overspread parts of the upper OH Valley and southern Mid-Atlantic through this evening. This enhanced flow along with upper-level difluence should provide sufficient large-scale ascent for isolated to scattered convection this afternoon across parts of OH into WV and western PA. Low-level moisture will remain somewhat limited across this area, with surface dewpoints generally in the low to mid 50s. Even with filtered daytime heating, poor lapse rates aloft should keep any more than weak instability from developing. Various RAP forecast soundings across this region also show flow backing with height aloft, which lends considerable uncertainty regarding convective organization. While an isolated damaging wind/hail threat may exist, the overall environment should keep the severe threat fairly marginal. A somewhat separate area of convection may develop this afternoon across eastern NC into VA, generally along/ahead of a weak surface front. While these thunderstorms will have access to greater low-level moisture, both instability and deep-layer shear are expected to remain modest. Still, some risk for damaging winds and hail should exist with any cells or clusters that can develop, before this activity gradually weakens through the evening with the loss of daytime heating. ...Florida... Scattered showers and thunderstorms are ongoing across parts of the southern/central FL Peninsula. A subtropical upper-level jet should continue to aid thunderstorm development across the FL Peninsula through the afternoon. But, persistent cloud cover and poor lapse rates aloft noted on area 12Z soundings may hinder destabilization to some degree. Even so, a rather moist low-level airmass exists along/south of a front over north FL/far southeast GA, and even modest further heating should support sufficient instability for surface-based convection. With weak low-level flow gradually veering to westerly and strengthening at mid/upper levels, this activity should have enough deep-layer shear for modest updraft organization. Thunderstorms may preferentially form on/near the Atlantic Coast sea breeze this afternoon while posing an isolated threat for severe hail, damaging winds, and perhaps a brief tornado. ...Eastern Idaho into Southern Montana... As a mid-level trough moves eastward over western Canada and the northern Rockies, scattered thunderstorms should develop this afternoon and evening across eastern Idaho into southwest Montana. This region will have steep mid-level lapse rates and cool temperatures aloft associated with the shortwave trough. Deep-layer shear is expected to remain modest, but a couple of stronger cores with small hail and gusty winds could still occur. ..Gleason/Squitieri.. 05/04/2025 Read more

SPC May 4, 2025 1630 UTC Day 1 Convective Outlook

4 months ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1125 AM CDT Sun May 04 2025 Valid 041630Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF EASTERN NEW MEXICO AND WEST TEXAS... ...SUMMARY... Scattered severe thunderstorms are expected across parts of eastern New Mexico and west Texas this afternoon and evening. Large to very large hail, isolated severe wind gusts, and possibly a tornado or two may occur. ...New Mexico and West Texas... Large-scale ascent will increase this afternoon across NM and the southern High Plains as strong difluence aloft associated with an upper low over northwest Mexico and the Southwest moves eastward. Steep lapse rates aloft atop modest low-level moisture will act in tandem with daytime heating to foster up to 1000-1250 J/kg of MLCAPE across eastern NM and far west TX by mid afternoon. While low-level southeasterly flow will initially be modest, various RAP/NAM forecast soundings show substantial veering and some strengthening with height at mid/upper levels. Resultant long/straight hodographs aloft and strong deep-layer shear will likely support a few supercells with an attendant threat for large to very large hail (up to 1.5-2.5 inches in diameter). Isolated severe wind gusts may also occur as this convection spreads slowly eastward across eastern NM into parts of west TX through the evening. Although low-level moisture will remain modest, a southeasterly low-level jet is also expected to gradually strengthen this evening, which should support enough 0-1 km SRH for a tornado or two with any sustained supercell. These thunderstorms will eventually weaken with eastward extent into west TX as MLCIN gradually increases by mid/late evening. ...Upper Ohio Valley/Mid-Atlantic to the Carolinas... An expansive closed mid/upper-level low will remain centered over the OH/TN Valleys today. A belt of stronger south-southwesterly mid-level winds will overspread parts of the upper OH Valley and southern Mid-Atlantic through this evening. This enhanced flow along with upper-level difluence should provide sufficient large-scale ascent for isolated to scattered convection this afternoon across parts of OH into WV and western PA. Low-level moisture will remain somewhat limited across this area, with surface dewpoints generally in the low to mid 50s. Even with filtered daytime heating, poor lapse rates aloft should keep any more than weak instability from developing. Various RAP forecast soundings across this region also show flow backing with height aloft, which lends considerable uncertainty regarding convective organization. While an isolated damaging wind/hail threat may exist, the overall environment should keep the severe threat fairly marginal. A somewhat separate area of convection may develop this afternoon across eastern NC into VA, generally along/ahead of a weak surface front. While these thunderstorms will have access to greater low-level moisture, both instability and deep-layer shear are expected to remain modest. Still, some risk for damaging winds and hail should exist with any cells or clusters that can develop, before this activity gradually weakens through the evening with the loss of daytime heating. ...Florida... Scattered showers and thunderstorms are ongoing across parts of the southern/central FL Peninsula. A subtropical upper-level jet should continue to aid thunderstorm development across the FL Peninsula through the afternoon. But, persistent cloud cover and poor lapse rates aloft noted on area 12Z soundings may hinder destabilization to some degree. Even so, a rather moist low-level airmass exists along/south of a front over north FL/far southeast GA, and even modest further heating should support sufficient instability for surface-based convection. With weak low-level flow gradually veering to westerly and strengthening at mid/upper levels, this activity should have enough deep-layer shear for modest updraft organization. Thunderstorms may preferentially form on/near the Atlantic Coast sea breeze this afternoon while posing an isolated threat for severe hail, damaging winds, and perhaps a brief tornado. ...Eastern Idaho into Southern Montana... As a mid-level trough moves eastward over western Canada and the northern Rockies, scattered thunderstorms should develop this afternoon and evening across eastern Idaho into southwest Montana. This region will have steep mid-level lapse rates and cool temperatures aloft associated with the shortwave trough. Deep-layer shear is expected to remain modest, but a couple of stronger cores with small hail and gusty winds could still occur. ..Gleason/Squitieri.. 05/04/2025 Read more

SPC May 4, 2025 1630 UTC Day 1 Convective Outlook

4 months ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1125 AM CDT Sun May 04 2025 Valid 041630Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF EASTERN NEW MEXICO AND WEST TEXAS... ...SUMMARY... Scattered severe thunderstorms are expected across parts of eastern New Mexico and west Texas this afternoon and evening. Large to very large hail, isolated severe wind gusts, and possibly a tornado or two may occur. ...New Mexico and West Texas... Large-scale ascent will increase this afternoon across NM and the southern High Plains as strong difluence aloft associated with an upper low over northwest Mexico and the Southwest moves eastward. Steep lapse rates aloft atop modest low-level moisture will act in tandem with daytime heating to foster up to 1000-1250 J/kg of MLCAPE across eastern NM and far west TX by mid afternoon. While low-level southeasterly flow will initially be modest, various RAP/NAM forecast soundings show substantial veering and some strengthening with height at mid/upper levels. Resultant long/straight hodographs aloft and strong deep-layer shear will likely support a few supercells with an attendant threat for large to very large hail (up to 1.5-2.5 inches in diameter). Isolated severe wind gusts may also occur as this convection spreads slowly eastward across eastern NM into parts of west TX through the evening. Although low-level moisture will remain modest, a southeasterly low-level jet is also expected to gradually strengthen this evening, which should support enough 0-1 km SRH for a tornado or two with any sustained supercell. These thunderstorms will eventually weaken with eastward extent into west TX as MLCIN gradually increases by mid/late evening. ...Upper Ohio Valley/Mid-Atlantic to the Carolinas... An expansive closed mid/upper-level low will remain centered over the OH/TN Valleys today. A belt of stronger south-southwesterly mid-level winds will overspread parts of the upper OH Valley and southern Mid-Atlantic through this evening. This enhanced flow along with upper-level difluence should provide sufficient large-scale ascent for isolated to scattered convection this afternoon across parts of OH into WV and western PA. Low-level moisture will remain somewhat limited across this area, with surface dewpoints generally in the low to mid 50s. Even with filtered daytime heating, poor lapse rates aloft should keep any more than weak instability from developing. Various RAP forecast soundings across this region also show flow backing with height aloft, which lends considerable uncertainty regarding convective organization. While an isolated damaging wind/hail threat may exist, the overall environment should keep the severe threat fairly marginal. A somewhat separate area of convection may develop this afternoon across eastern NC into VA, generally along/ahead of a weak surface front. While these thunderstorms will have access to greater low-level moisture, both instability and deep-layer shear are expected to remain modest. Still, some risk for damaging winds and hail should exist with any cells or clusters that can develop, before this activity gradually weakens through the evening with the loss of daytime heating. ...Florida... Scattered showers and thunderstorms are ongoing across parts of the southern/central FL Peninsula. A subtropical upper-level jet should continue to aid thunderstorm development across the FL Peninsula through the afternoon. But, persistent cloud cover and poor lapse rates aloft noted on area 12Z soundings may hinder destabilization to some degree. Even so, a rather moist low-level airmass exists along/south of a front over north FL/far southeast GA, and even modest further heating should support sufficient instability for surface-based convection. With weak low-level flow gradually veering to westerly and strengthening at mid/upper levels, this activity should have enough deep-layer shear for modest updraft organization. Thunderstorms may preferentially form on/near the Atlantic Coast sea breeze this afternoon while posing an isolated threat for severe hail, damaging winds, and perhaps a brief tornado. ...Eastern Idaho into Southern Montana... As a mid-level trough moves eastward over western Canada and the northern Rockies, scattered thunderstorms should develop this afternoon and evening across eastern Idaho into southwest Montana. This region will have steep mid-level lapse rates and cool temperatures aloft associated with the shortwave trough. Deep-layer shear is expected to remain modest, but a couple of stronger cores with small hail and gusty winds could still occur. ..Gleason/Squitieri.. 05/04/2025 Read more

SPC May 4, 2025 1630 UTC Day 1 Convective Outlook

4 months ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1125 AM CDT Sun May 04 2025 Valid 041630Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF EASTERN NEW MEXICO AND WEST TEXAS... ...SUMMARY... Scattered severe thunderstorms are expected across parts of eastern New Mexico and west Texas this afternoon and evening. Large to very large hail, isolated severe wind gusts, and possibly a tornado or two may occur. ...New Mexico and West Texas... Large-scale ascent will increase this afternoon across NM and the southern High Plains as strong difluence aloft associated with an upper low over northwest Mexico and the Southwest moves eastward. Steep lapse rates aloft atop modest low-level moisture will act in tandem with daytime heating to foster up to 1000-1250 J/kg of MLCAPE across eastern NM and far west TX by mid afternoon. While low-level southeasterly flow will initially be modest, various RAP/NAM forecast soundings show substantial veering and some strengthening with height at mid/upper levels. Resultant long/straight hodographs aloft and strong deep-layer shear will likely support a few supercells with an attendant threat for large to very large hail (up to 1.5-2.5 inches in diameter). Isolated severe wind gusts may also occur as this convection spreads slowly eastward across eastern NM into parts of west TX through the evening. Although low-level moisture will remain modest, a southeasterly low-level jet is also expected to gradually strengthen this evening, which should support enough 0-1 km SRH for a tornado or two with any sustained supercell. These thunderstorms will eventually weaken with eastward extent into west TX as MLCIN gradually increases by mid/late evening. ...Upper Ohio Valley/Mid-Atlantic to the Carolinas... An expansive closed mid/upper-level low will remain centered over the OH/TN Valleys today. A belt of stronger south-southwesterly mid-level winds will overspread parts of the upper OH Valley and southern Mid-Atlantic through this evening. This enhanced flow along with upper-level difluence should provide sufficient large-scale ascent for isolated to scattered convection this afternoon across parts of OH into WV and western PA. Low-level moisture will remain somewhat limited across this area, with surface dewpoints generally in the low to mid 50s. Even with filtered daytime heating, poor lapse rates aloft should keep any more than weak instability from developing. Various RAP forecast soundings across this region also show flow backing with height aloft, which lends considerable uncertainty regarding convective organization. While an isolated damaging wind/hail threat may exist, the overall environment should keep the severe threat fairly marginal. A somewhat separate area of convection may develop this afternoon across eastern NC into VA, generally along/ahead of a weak surface front. While these thunderstorms will have access to greater low-level moisture, both instability and deep-layer shear are expected to remain modest. Still, some risk for damaging winds and hail should exist with any cells or clusters that can develop, before this activity gradually weakens through the evening with the loss of daytime heating. ...Florida... Scattered showers and thunderstorms are ongoing across parts of the southern/central FL Peninsula. A subtropical upper-level jet should continue to aid thunderstorm development across the FL Peninsula through the afternoon. But, persistent cloud cover and poor lapse rates aloft noted on area 12Z soundings may hinder destabilization to some degree. Even so, a rather moist low-level airmass exists along/south of a front over north FL/far southeast GA, and even modest further heating should support sufficient instability for surface-based convection. With weak low-level flow gradually veering to westerly and strengthening at mid/upper levels, this activity should have enough deep-layer shear for modest updraft organization. Thunderstorms may preferentially form on/near the Atlantic Coast sea breeze this afternoon while posing an isolated threat for severe hail, damaging winds, and perhaps a brief tornado. ...Eastern Idaho into Southern Montana... As a mid-level trough moves eastward over western Canada and the northern Rockies, scattered thunderstorms should develop this afternoon and evening across eastern Idaho into southwest Montana. This region will have steep mid-level lapse rates and cool temperatures aloft associated with the shortwave trough. Deep-layer shear is expected to remain modest, but a couple of stronger cores with small hail and gusty winds could still occur. ..Gleason/Squitieri.. 05/04/2025 Read more

SPC May 4, 2025 1630 UTC Day 1 Convective Outlook

4 months ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1125 AM CDT Sun May 04 2025 Valid 041630Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF EASTERN NEW MEXICO AND WEST TEXAS... ...SUMMARY... Scattered severe thunderstorms are expected across parts of eastern New Mexico and west Texas this afternoon and evening. Large to very large hail, isolated severe wind gusts, and possibly a tornado or two may occur. ...New Mexico and West Texas... Large-scale ascent will increase this afternoon across NM and the southern High Plains as strong difluence aloft associated with an upper low over northwest Mexico and the Southwest moves eastward. Steep lapse rates aloft atop modest low-level moisture will act in tandem with daytime heating to foster up to 1000-1250 J/kg of MLCAPE across eastern NM and far west TX by mid afternoon. While low-level southeasterly flow will initially be modest, various RAP/NAM forecast soundings show substantial veering and some strengthening with height at mid/upper levels. Resultant long/straight hodographs aloft and strong deep-layer shear will likely support a few supercells with an attendant threat for large to very large hail (up to 1.5-2.5 inches in diameter). Isolated severe wind gusts may also occur as this convection spreads slowly eastward across eastern NM into parts of west TX through the evening. Although low-level moisture will remain modest, a southeasterly low-level jet is also expected to gradually strengthen this evening, which should support enough 0-1 km SRH for a tornado or two with any sustained supercell. These thunderstorms will eventually weaken with eastward extent into west TX as MLCIN gradually increases by mid/late evening. ...Upper Ohio Valley/Mid-Atlantic to the Carolinas... An expansive closed mid/upper-level low will remain centered over the OH/TN Valleys today. A belt of stronger south-southwesterly mid-level winds will overspread parts of the upper OH Valley and southern Mid-Atlantic through this evening. This enhanced flow along with upper-level difluence should provide sufficient large-scale ascent for isolated to scattered convection this afternoon across parts of OH into WV and western PA. Low-level moisture will remain somewhat limited across this area, with surface dewpoints generally in the low to mid 50s. Even with filtered daytime heating, poor lapse rates aloft should keep any more than weak instability from developing. Various RAP forecast soundings across this region also show flow backing with height aloft, which lends considerable uncertainty regarding convective organization. While an isolated damaging wind/hail threat may exist, the overall environment should keep the severe threat fairly marginal. A somewhat separate area of convection may develop this afternoon across eastern NC into VA, generally along/ahead of a weak surface front. While these thunderstorms will have access to greater low-level moisture, both instability and deep-layer shear are expected to remain modest. Still, some risk for damaging winds and hail should exist with any cells or clusters that can develop, before this activity gradually weakens through the evening with the loss of daytime heating. ...Florida... Scattered showers and thunderstorms are ongoing across parts of the southern/central FL Peninsula. A subtropical upper-level jet should continue to aid thunderstorm development across the FL Peninsula through the afternoon. But, persistent cloud cover and poor lapse rates aloft noted on area 12Z soundings may hinder destabilization to some degree. Even so, a rather moist low-level airmass exists along/south of a front over north FL/far southeast GA, and even modest further heating should support sufficient instability for surface-based convection. With weak low-level flow gradually veering to westerly and strengthening at mid/upper levels, this activity should have enough deep-layer shear for modest updraft organization. Thunderstorms may preferentially form on/near the Atlantic Coast sea breeze this afternoon while posing an isolated threat for severe hail, damaging winds, and perhaps a brief tornado. ...Eastern Idaho into Southern Montana... As a mid-level trough moves eastward over western Canada and the northern Rockies, scattered thunderstorms should develop this afternoon and evening across eastern Idaho into southwest Montana. This region will have steep mid-level lapse rates and cool temperatures aloft associated with the shortwave trough. Deep-layer shear is expected to remain modest, but a couple of stronger cores with small hail and gusty winds could still occur. ..Gleason/Squitieri.. 05/04/2025 Read more

SPC May 4, 2025 1630 UTC Day 1 Convective Outlook

4 months ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1125 AM CDT Sun May 04 2025 Valid 041630Z - 051200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF EASTERN NEW MEXICO AND WEST TEXAS... ...SUMMARY... Scattered severe thunderstorms are expected across parts of eastern New Mexico and west Texas this afternoon and evening. Large to very large hail, isolated severe wind gusts, and possibly a tornado or two may occur. ...New Mexico and West Texas... Large-scale ascent will increase this afternoon across NM and the southern High Plains as strong difluence aloft associated with an upper low over northwest Mexico and the Southwest moves eastward. Steep lapse rates aloft atop modest low-level moisture will act in tandem with daytime heating to foster up to 1000-1250 J/kg of MLCAPE across eastern NM and far west TX by mid afternoon. While low-level southeasterly flow will initially be modest, various RAP/NAM forecast soundings show substantial veering and some strengthening with height at mid/upper levels. Resultant long/straight hodographs aloft and strong deep-layer shear will likely support a few supercells with an attendant threat for large to very large hail (up to 1.5-2.5 inches in diameter). Isolated severe wind gusts may also occur as this convection spreads slowly eastward across eastern NM into parts of west TX through the evening. Although low-level moisture will remain modest, a southeasterly low-level jet is also expected to gradually strengthen this evening, which should support enough 0-1 km SRH for a tornado or two with any sustained supercell. These thunderstorms will eventually weaken with eastward extent into west TX as MLCIN gradually increases by mid/late evening. ...Upper Ohio Valley/Mid-Atlantic to the Carolinas... An expansive closed mid/upper-level low will remain centered over the OH/TN Valleys today. A belt of stronger south-southwesterly mid-level winds will overspread parts of the upper OH Valley and southern Mid-Atlantic through this evening. This enhanced flow along with upper-level difluence should provide sufficient large-scale ascent for isolated to scattered convection this afternoon across parts of OH into WV and western PA. Low-level moisture will remain somewhat limited across this area, with surface dewpoints generally in the low to mid 50s. Even with filtered daytime heating, poor lapse rates aloft should keep any more than weak instability from developing. Various RAP forecast soundings across this region also show flow backing with height aloft, which lends considerable uncertainty regarding convective organization. While an isolated damaging wind/hail threat may exist, the overall environment should keep the severe threat fairly marginal. A somewhat separate area of convection may develop this afternoon across eastern NC into VA, generally along/ahead of a weak surface front. While these thunderstorms will have access to greater low-level moisture, both instability and deep-layer shear are expected to remain modest. Still, some risk for damaging winds and hail should exist with any cells or clusters that can develop, before this activity gradually weakens through the evening with the loss of daytime heating. ...Florida... Scattered showers and thunderstorms are ongoing across parts of the southern/central FL Peninsula. A subtropical upper-level jet should continue to aid thunderstorm development across the FL Peninsula through the afternoon. But, persistent cloud cover and poor lapse rates aloft noted on area 12Z soundings may hinder destabilization to some degree. Even so, a rather moist low-level airmass exists along/south of a front over north FL/far southeast GA, and even modest further heating should support sufficient instability for surface-based convection. With weak low-level flow gradually veering to westerly and strengthening at mid/upper levels, this activity should have enough deep-layer shear for modest updraft organization. Thunderstorms may preferentially form on/near the Atlantic Coast sea breeze this afternoon while posing an isolated threat for severe hail, damaging winds, and perhaps a brief tornado. ...Eastern Idaho into Southern Montana... As a mid-level trough moves eastward over western Canada and the northern Rockies, scattered thunderstorms should develop this afternoon and evening across eastern Idaho into southwest Montana. This region will have steep mid-level lapse rates and cool temperatures aloft associated with the shortwave trough. Deep-layer shear is expected to remain modest, but a couple of stronger cores with small hail and gusty winds could still occur. ..Gleason/Squitieri.. 05/04/2025 Read more

SPC Day 1 Fire Weather Outlook

4 months ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1126 AM CDT Sun May 04 2025 Valid 041700Z - 051200Z ...CRITICAL FIRE WEATHER AREA FOR SOUTHWEST NEW MEXICO... Slight adjustments were made to the D1 Elevated and Critical areas in New Mexico to remove Catron and Socorro counties where more recent rainfall has occurred and additional rainfall is possible today. See previous discussion for more information. ..Thornton.. 05/04/2025 .PREV DISCUSSION... /ISSUED 0135 AM CDT Sun May 04 2025/ ...Synopsis... Fire weather concerns are expected across parts of the Southwest and northern Plains this afternoon. Early-morning water-vapor imagery depict an upper wave over southern CA with a broad zone of ascent overspreading the Great Basin and Southwest. At the surface, pressure falls are noted over the Four Corners region and northern High Plains and should continue well into the afternoon hours as the upper wave gradually drifts east. Increasing southerly winds across along both international borders should result in areas of dry/windy conditions. ...Southwest New Mexico... Dewpoints in the low teens are noted in far southeast AZ early this morning, which appear to be the northwestern periphery of a very dry air mass in place across northern Mexico based on recent RTMA analyses. This air mass will spread north through the day as southerly winds increase in response the surface low development over the Four Corners region. Afternoon RH minimums in the teens are likely with 15-25 mph overspreading much of southeast AZ and southwest NM. Elevated to critical fire weather conditions are expected over an area with receptive fuels. Dry/windy conditions may extend well north of the current outline lines, but recent rainfall and/or the potential for showers/thunderstorms this afternoon should limit the spatial extent of the threat. ...North Dakota... Southerly winds between 15-20 mph are expected across much of the northern Plains this afternoon as a surface trough deepens along the northern High Plains. A recent frontal intrusion into the Gulf has shunted appreciable moisture well south into the southern Plains, limiting the potential for moisture return over the next 12 hours. Additionally, unseasonably warm high temperatures are forecast for today (into the 80s), which will support RH reductions to near 20%. Elevated to critical fire weather conditions are likely - especially along and north of the Highway 2 corridor where recent HRRR/RAP runs (which typically handle dry return flow regimes well) show the highest potential for sustained 20 mph winds. Although much of the region has received some rainfall within the past week, local fuel and fire reports indicate that dry/dead grasses remain in the fuel landscape and should support fire spread. ...Please see www.spc.noaa.gov/fire for graphic product... Read more