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SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 AM CDT Sat Jul 05 2025 Valid 071200Z - 081200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE CENTRAL PLAINS... ...SUMMARY... Severe storms are possible across the central Plains on Monday. Severe wind and hail are the main threats. Isolated strong to potentially severe storms are also possible over the northern Appalachians. ...Synopsis... Zonal mid-level flow will persevere over the northern CONUS as a mid-level trough meanders along the CA coastline on Monday. Mid-level impulses, embedded in the zonal flow aloft, will traverse the Upper MS Valley and New England during the afternoon, acting as a source of lift amid adequate moisture, instability, and vertical wind shear, to support the potential for strong thunderstorms, a few of which could become severe, especially over the central Plains. ...Central Plains into the Upper MS Valley... A weak surface low will develop across the central High Plains and augment northward moisture transport beneath a plume of steep mid-level lapse rates. 60 F surface dewpoints beneath 8 C/km mid-level lapse rates will yield 2000+ J/kg MLCAPE by peak heating. Furthermore modest northwesterly 500 mb flow associated with the impulse will overspread the central Plains, resulting in 40 kts of effective bulk shear. Given modestly elongated and curved hodographs, supercells may develop, accompanied by a severe wind and hail threat (with a few stones potentially exceeding 2 inches in diameter). A tornado is also possible, particularly in central Nebraska, where forecast hodographs show larger, curved low-level hodographs. Storms may grow upscale into an MCS by evening, accompanied by mainly a severe gust threat. Strong storms may develop farther northeast into the Upper MS Valley during the late afternoon/early evening hours. Though buoyancy will be slightly weaker compared to the central Plains, elongated hodographs suggest that a few supercells may produce isolated instances of severe hail. ...Portions of the Northern Appalachians... A mid-level impulse embedded in the 500 mb flow will impinge on the northern Appalachians by afternoon peak heating, providing enough lift for convective initiation. Near 70F surface dewpoints beneath modest lapse rates will contribute to 2000 J/kg MLCAPE in tall/thin thermodynamic profiles. Forecast soundings depict hodographs with some low-level curvature and size, suggesting that some storms may become strong and organized. Multicells and supercells may pose a damaging gust threat. ..Squitieri.. 07/05/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 AM CDT Sat Jul 05 2025 Valid 071200Z - 081200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE CENTRAL PLAINS... ...SUMMARY... Severe storms are possible across the central Plains on Monday. Severe wind and hail are the main threats. Isolated strong to potentially severe storms are also possible over the northern Appalachians. ...Synopsis... Zonal mid-level flow will persevere over the northern CONUS as a mid-level trough meanders along the CA coastline on Monday. Mid-level impulses, embedded in the zonal flow aloft, will traverse the Upper MS Valley and New England during the afternoon, acting as a source of lift amid adequate moisture, instability, and vertical wind shear, to support the potential for strong thunderstorms, a few of which could become severe, especially over the central Plains. ...Central Plains into the Upper MS Valley... A weak surface low will develop across the central High Plains and augment northward moisture transport beneath a plume of steep mid-level lapse rates. 60 F surface dewpoints beneath 8 C/km mid-level lapse rates will yield 2000+ J/kg MLCAPE by peak heating. Furthermore modest northwesterly 500 mb flow associated with the impulse will overspread the central Plains, resulting in 40 kts of effective bulk shear. Given modestly elongated and curved hodographs, supercells may develop, accompanied by a severe wind and hail threat (with a few stones potentially exceeding 2 inches in diameter). A tornado is also possible, particularly in central Nebraska, where forecast hodographs show larger, curved low-level hodographs. Storms may grow upscale into an MCS by evening, accompanied by mainly a severe gust threat. Strong storms may develop farther northeast into the Upper MS Valley during the late afternoon/early evening hours. Though buoyancy will be slightly weaker compared to the central Plains, elongated hodographs suggest that a few supercells may produce isolated instances of severe hail. ...Portions of the Northern Appalachians... A mid-level impulse embedded in the 500 mb flow will impinge on the northern Appalachians by afternoon peak heating, providing enough lift for convective initiation. Near 70F surface dewpoints beneath modest lapse rates will contribute to 2000 J/kg MLCAPE in tall/thin thermodynamic profiles. Forecast soundings depict hodographs with some low-level curvature and size, suggesting that some storms may become strong and organized. Multicells and supercells may pose a damaging gust threat. ..Squitieri.. 07/05/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 AM CDT Sat Jul 05 2025 Valid 071200Z - 081200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE CENTRAL PLAINS... ...SUMMARY... Severe storms are possible across the central Plains on Monday. Severe wind and hail are the main threats. Isolated strong to potentially severe storms are also possible over the northern Appalachians. ...Synopsis... Zonal mid-level flow will persevere over the northern CONUS as a mid-level trough meanders along the CA coastline on Monday. Mid-level impulses, embedded in the zonal flow aloft, will traverse the Upper MS Valley and New England during the afternoon, acting as a source of lift amid adequate moisture, instability, and vertical wind shear, to support the potential for strong thunderstorms, a few of which could become severe, especially over the central Plains. ...Central Plains into the Upper MS Valley... A weak surface low will develop across the central High Plains and augment northward moisture transport beneath a plume of steep mid-level lapse rates. 60 F surface dewpoints beneath 8 C/km mid-level lapse rates will yield 2000+ J/kg MLCAPE by peak heating. Furthermore modest northwesterly 500 mb flow associated with the impulse will overspread the central Plains, resulting in 40 kts of effective bulk shear. Given modestly elongated and curved hodographs, supercells may develop, accompanied by a severe wind and hail threat (with a few stones potentially exceeding 2 inches in diameter). A tornado is also possible, particularly in central Nebraska, where forecast hodographs show larger, curved low-level hodographs. Storms may grow upscale into an MCS by evening, accompanied by mainly a severe gust threat. Strong storms may develop farther northeast into the Upper MS Valley during the late afternoon/early evening hours. Though buoyancy will be slightly weaker compared to the central Plains, elongated hodographs suggest that a few supercells may produce isolated instances of severe hail. ...Portions of the Northern Appalachians... A mid-level impulse embedded in the 500 mb flow will impinge on the northern Appalachians by afternoon peak heating, providing enough lift for convective initiation. Near 70F surface dewpoints beneath modest lapse rates will contribute to 2000 J/kg MLCAPE in tall/thin thermodynamic profiles. Forecast soundings depict hodographs with some low-level curvature and size, suggesting that some storms may become strong and organized. Multicells and supercells may pose a damaging gust threat. ..Squitieri.. 07/05/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 AM CDT Sat Jul 05 2025 Valid 071200Z - 081200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE CENTRAL PLAINS... ...SUMMARY... Severe storms are possible across the central Plains on Monday. Severe wind and hail are the main threats. Isolated strong to potentially severe storms are also possible over the northern Appalachians. ...Synopsis... Zonal mid-level flow will persevere over the northern CONUS as a mid-level trough meanders along the CA coastline on Monday. Mid-level impulses, embedded in the zonal flow aloft, will traverse the Upper MS Valley and New England during the afternoon, acting as a source of lift amid adequate moisture, instability, and vertical wind shear, to support the potential for strong thunderstorms, a few of which could become severe, especially over the central Plains. ...Central Plains into the Upper MS Valley... A weak surface low will develop across the central High Plains and augment northward moisture transport beneath a plume of steep mid-level lapse rates. 60 F surface dewpoints beneath 8 C/km mid-level lapse rates will yield 2000+ J/kg MLCAPE by peak heating. Furthermore modest northwesterly 500 mb flow associated with the impulse will overspread the central Plains, resulting in 40 kts of effective bulk shear. Given modestly elongated and curved hodographs, supercells may develop, accompanied by a severe wind and hail threat (with a few stones potentially exceeding 2 inches in diameter). A tornado is also possible, particularly in central Nebraska, where forecast hodographs show larger, curved low-level hodographs. Storms may grow upscale into an MCS by evening, accompanied by mainly a severe gust threat. Strong storms may develop farther northeast into the Upper MS Valley during the late afternoon/early evening hours. Though buoyancy will be slightly weaker compared to the central Plains, elongated hodographs suggest that a few supercells may produce isolated instances of severe hail. ...Portions of the Northern Appalachians... A mid-level impulse embedded in the 500 mb flow will impinge on the northern Appalachians by afternoon peak heating, providing enough lift for convective initiation. Near 70F surface dewpoints beneath modest lapse rates will contribute to 2000 J/kg MLCAPE in tall/thin thermodynamic profiles. Forecast soundings depict hodographs with some low-level curvature and size, suggesting that some storms may become strong and organized. Multicells and supercells may pose a damaging gust threat. ..Squitieri.. 07/05/2025 Read more

5-Day Uncertainty Track last updated Sat, 05 Jul 2025 05:46:08 GMT


Wind Speed Probabilities last updated Sat, 05 Jul 2025 03:21:51 GMT

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0129 AM CDT Sat Jul 05 2025 Valid 061200Z - 071200Z ...NO CRITICAL AREAS... ...Synopsis... A belt of modest flow across will be in place across the northern states during the day on Sunday with a weak cutoff low off the coast of California and a ridge across much of the southwestern CONUS. Some of the mid-level flow around the periphery of the cutoff low may mix down to the surface across portions of the Great Basin during the afternoon amid low RH. However, given a lack of strong flow throughout the column across the region, any Elevated fire weather conditions are expected to be localized and transient. Therefore, no highlights have been added at this time. ..Supinie.. 07/05/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0129 AM CDT Sat Jul 05 2025 Valid 061200Z - 071200Z ...NO CRITICAL AREAS... ...Synopsis... A belt of modest flow across will be in place across the northern states during the day on Sunday with a weak cutoff low off the coast of California and a ridge across much of the southwestern CONUS. Some of the mid-level flow around the periphery of the cutoff low may mix down to the surface across portions of the Great Basin during the afternoon amid low RH. However, given a lack of strong flow throughout the column across the region, any Elevated fire weather conditions are expected to be localized and transient. Therefore, no highlights have been added at this time. ..Supinie.. 07/05/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0129 AM CDT Sat Jul 05 2025 Valid 061200Z - 071200Z ...NO CRITICAL AREAS... ...Synopsis... A belt of modest flow across will be in place across the northern states during the day on Sunday with a weak cutoff low off the coast of California and a ridge across much of the southwestern CONUS. Some of the mid-level flow around the periphery of the cutoff low may mix down to the surface across portions of the Great Basin during the afternoon amid low RH. However, given a lack of strong flow throughout the column across the region, any Elevated fire weather conditions are expected to be localized and transient. Therefore, no highlights have been added at this time. ..Supinie.. 07/05/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0129 AM CDT Sat Jul 05 2025 Valid 061200Z - 071200Z ...NO CRITICAL AREAS... ...Synopsis... A belt of modest flow across will be in place across the northern states during the day on Sunday with a weak cutoff low off the coast of California and a ridge across much of the southwestern CONUS. Some of the mid-level flow around the periphery of the cutoff low may mix down to the surface across portions of the Great Basin during the afternoon amid low RH. However, given a lack of strong flow throughout the column across the region, any Elevated fire weather conditions are expected to be localized and transient. Therefore, no highlights have been added at this time. ..Supinie.. 07/05/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0129 AM CDT Sat Jul 05 2025 Valid 051200Z - 061200Z ...Synopsis... A mid-level ridge will continue to build across the southern Rockies through the day. A weak 700 mb jet around the northwestern periphery of the ridge is expected to mix downward amid strong surface heating and provide a focus for fire weather concerns across portions of the Great Basin. Winds may gust to 20-25 mph with 5-15% RH during the afternoon. Therefore, an Elevated highlight has been maintained across portions of southeastern Nevada and southwestern Utah where these atmospheric conditions overlap with dry fuels that have not received wetting rain recently. ..Supinie.. 07/05/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0129 AM CDT Sat Jul 05 2025 Valid 051200Z - 061200Z ...Synopsis... A mid-level ridge will continue to build across the southern Rockies through the day. A weak 700 mb jet around the northwestern periphery of the ridge is expected to mix downward amid strong surface heating and provide a focus for fire weather concerns across portions of the Great Basin. Winds may gust to 20-25 mph with 5-15% RH during the afternoon. Therefore, an Elevated highlight has been maintained across portions of southeastern Nevada and southwestern Utah where these atmospheric conditions overlap with dry fuels that have not received wetting rain recently. ..Supinie.. 07/05/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0129 AM CDT Sat Jul 05 2025 Valid 051200Z - 061200Z ...Synopsis... A mid-level ridge will continue to build across the southern Rockies through the day. A weak 700 mb jet around the northwestern periphery of the ridge is expected to mix downward amid strong surface heating and provide a focus for fire weather concerns across portions of the Great Basin. Winds may gust to 20-25 mph with 5-15% RH during the afternoon. Therefore, an Elevated highlight has been maintained across portions of southeastern Nevada and southwestern Utah where these atmospheric conditions overlap with dry fuels that have not received wetting rain recently. ..Supinie.. 07/05/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0129 AM CDT Sat Jul 05 2025 Valid 051200Z - 061200Z ...Synopsis... A mid-level ridge will continue to build across the southern Rockies through the day. A weak 700 mb jet around the northwestern periphery of the ridge is expected to mix downward amid strong surface heating and provide a focus for fire weather concerns across portions of the Great Basin. Winds may gust to 20-25 mph with 5-15% RH during the afternoon. Therefore, an Elevated highlight has been maintained across portions of southeastern Nevada and southwestern Utah where these atmospheric conditions overlap with dry fuels that have not received wetting rain recently. ..Supinie.. 07/05/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0129 AM CDT Sat Jul 05 2025 Valid 051200Z - 061200Z ...Synopsis... A mid-level ridge will continue to build across the southern Rockies through the day. A weak 700 mb jet around the northwestern periphery of the ridge is expected to mix downward amid strong surface heating and provide a focus for fire weather concerns across portions of the Great Basin. Winds may gust to 20-25 mph with 5-15% RH during the afternoon. Therefore, an Elevated highlight has been maintained across portions of southeastern Nevada and southwestern Utah where these atmospheric conditions overlap with dry fuels that have not received wetting rain recently. ..Supinie.. 07/05/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1255 AM CDT Sat Jul 05 2025 Valid 061200Z - 071200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE CENTRAL HIGH PLAINS... ...SUMMARY... Storms may produce severe wind and hail along the central High Plains tomorrow (Sunday). A few instances of 2+ inch diameter hail and 75+ mph wind gusts are possible. ...Synopsis... Mainly zonal upper flow will become established over the northern CONUS, with multiple embedded impulses poised to traverse the zonal flow through the day tomorrow (Sunday). The best chance for strong storms will be associated with mid-level impulses impinging on the High Plains and New England Sunday afternoon. Ample moisture and associated instability will precede the impulses, that combined with adequate vertical wind shear, will support storm organization, some of which could be severe. ...Maine... A belt of 50 kt westerly 500 mb flow will overspread southeast Quebec into Maine Sunday afternoon with the overhead passage of a mid-level impulse. Surface lee troughing over Maine will serve as an impetus for thunderstorm initiation during the afternoon, when surface temperatures/dewpoints in the low 80s/upper 60s F will boost MLCAPE to over 1000 J/kg. Modestly curved, sizeable low-level hodographs suggest that multicells and supercells will be the main storm mode, possibly accompanied by damaging gusts. ...Central and Southern High Plains... Low-level upslope flow will encourage the northwestward advection of 60s F surface dewpoints into the higher terrain of the High Plains Sunday afternoon, beneath 8-9 C/km 700-500 mb lapse rates. Moderate to strong instability will manifest, with over 3000 J/kg MLCAPE possible. Storms will initiate over the higher terrain, amid straight hodographs, contributing to splitting supercell potential. By evening, the southeasterly surface flow will be overspread by a strengthening southerly low-level jet, with flow quickly veering to westerly in the 700-500 mb layer. This directional shear will support curved low-level hodographs with continued supercell potential, before storms merge into an MCS by evening. While in the supercell phase, a few instances of severe hail (perhaps an instance or two of 2+ inch diameter hail) are possible, along with severe gusts and perhaps a tornado. By the time storms merge into an MCS, severe gusts will become the primary threat, and a few gusts exceeding 75 mph will be possible. Higher severe probabilities may be needed if confidence increases in a longer-lived, severe-wind producing MCS developing. Farther south into the southern High Plains, storm coverage should be relatively less, with multicells becoming outflow dominant more quickly given weaker vertical wind shear compared to the central High Plains. Nonetheless, an instance or two of hail is possible, along with severe gusts, especially with multicellular cold-pool mergers. ...Coastal Carolinas... A tropical storm is forecast to make landfall along the Carolina coastline at the start of the Day 2 period/12Z Sunday (please see the National Hurricane Center's advisories for more information on the progression of Tropical Depression 3). A deeply moist troposphere will accompany the land-falling TC, with MLCAPE approaching the 750-1000 J/kg range. Nonetheless, the vertical wind fields associated with this land-falling tropical storm are expected to quickly weaken, along with vertical wind shear. As such, while the risk for a brief tornado is technically non-zero, confidence in any robust tornado coverage is too low for the introduction of 2 percent or greater tornado probabilities at this time. ..Squitieri.. 07/05/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1255 AM CDT Sat Jul 05 2025 Valid 061200Z - 071200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE CENTRAL HIGH PLAINS... ...SUMMARY... Storms may produce severe wind and hail along the central High Plains tomorrow (Sunday). A few instances of 2+ inch diameter hail and 75+ mph wind gusts are possible. ...Synopsis... Mainly zonal upper flow will become established over the northern CONUS, with multiple embedded impulses poised to traverse the zonal flow through the day tomorrow (Sunday). The best chance for strong storms will be associated with mid-level impulses impinging on the High Plains and New England Sunday afternoon. Ample moisture and associated instability will precede the impulses, that combined with adequate vertical wind shear, will support storm organization, some of which could be severe. ...Maine... A belt of 50 kt westerly 500 mb flow will overspread southeast Quebec into Maine Sunday afternoon with the overhead passage of a mid-level impulse. Surface lee troughing over Maine will serve as an impetus for thunderstorm initiation during the afternoon, when surface temperatures/dewpoints in the low 80s/upper 60s F will boost MLCAPE to over 1000 J/kg. Modestly curved, sizeable low-level hodographs suggest that multicells and supercells will be the main storm mode, possibly accompanied by damaging gusts. ...Central and Southern High Plains... Low-level upslope flow will encourage the northwestward advection of 60s F surface dewpoints into the higher terrain of the High Plains Sunday afternoon, beneath 8-9 C/km 700-500 mb lapse rates. Moderate to strong instability will manifest, with over 3000 J/kg MLCAPE possible. Storms will initiate over the higher terrain, amid straight hodographs, contributing to splitting supercell potential. By evening, the southeasterly surface flow will be overspread by a strengthening southerly low-level jet, with flow quickly veering to westerly in the 700-500 mb layer. This directional shear will support curved low-level hodographs with continued supercell potential, before storms merge into an MCS by evening. While in the supercell phase, a few instances of severe hail (perhaps an instance or two of 2+ inch diameter hail) are possible, along with severe gusts and perhaps a tornado. By the time storms merge into an MCS, severe gusts will become the primary threat, and a few gusts exceeding 75 mph will be possible. Higher severe probabilities may be needed if confidence increases in a longer-lived, severe-wind producing MCS developing. Farther south into the southern High Plains, storm coverage should be relatively less, with multicells becoming outflow dominant more quickly given weaker vertical wind shear compared to the central High Plains. Nonetheless, an instance or two of hail is possible, along with severe gusts, especially with multicellular cold-pool mergers. ...Coastal Carolinas... A tropical storm is forecast to make landfall along the Carolina coastline at the start of the Day 2 period/12Z Sunday (please see the National Hurricane Center's advisories for more information on the progression of Tropical Depression 3). A deeply moist troposphere will accompany the land-falling TC, with MLCAPE approaching the 750-1000 J/kg range. Nonetheless, the vertical wind fields associated with this land-falling tropical storm are expected to quickly weaken, along with vertical wind shear. As such, while the risk for a brief tornado is technically non-zero, confidence in any robust tornado coverage is too low for the introduction of 2 percent or greater tornado probabilities at this time. ..Squitieri.. 07/05/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1255 AM CDT Sat Jul 05 2025 Valid 061200Z - 071200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE CENTRAL HIGH PLAINS... ...SUMMARY... Storms may produce severe wind and hail along the central High Plains tomorrow (Sunday). A few instances of 2+ inch diameter hail and 75+ mph wind gusts are possible. ...Synopsis... Mainly zonal upper flow will become established over the northern CONUS, with multiple embedded impulses poised to traverse the zonal flow through the day tomorrow (Sunday). The best chance for strong storms will be associated with mid-level impulses impinging on the High Plains and New England Sunday afternoon. Ample moisture and associated instability will precede the impulses, that combined with adequate vertical wind shear, will support storm organization, some of which could be severe. ...Maine... A belt of 50 kt westerly 500 mb flow will overspread southeast Quebec into Maine Sunday afternoon with the overhead passage of a mid-level impulse. Surface lee troughing over Maine will serve as an impetus for thunderstorm initiation during the afternoon, when surface temperatures/dewpoints in the low 80s/upper 60s F will boost MLCAPE to over 1000 J/kg. Modestly curved, sizeable low-level hodographs suggest that multicells and supercells will be the main storm mode, possibly accompanied by damaging gusts. ...Central and Southern High Plains... Low-level upslope flow will encourage the northwestward advection of 60s F surface dewpoints into the higher terrain of the High Plains Sunday afternoon, beneath 8-9 C/km 700-500 mb lapse rates. Moderate to strong instability will manifest, with over 3000 J/kg MLCAPE possible. Storms will initiate over the higher terrain, amid straight hodographs, contributing to splitting supercell potential. By evening, the southeasterly surface flow will be overspread by a strengthening southerly low-level jet, with flow quickly veering to westerly in the 700-500 mb layer. This directional shear will support curved low-level hodographs with continued supercell potential, before storms merge into an MCS by evening. While in the supercell phase, a few instances of severe hail (perhaps an instance or two of 2+ inch diameter hail) are possible, along with severe gusts and perhaps a tornado. By the time storms merge into an MCS, severe gusts will become the primary threat, and a few gusts exceeding 75 mph will be possible. Higher severe probabilities may be needed if confidence increases in a longer-lived, severe-wind producing MCS developing. Farther south into the southern High Plains, storm coverage should be relatively less, with multicells becoming outflow dominant more quickly given weaker vertical wind shear compared to the central High Plains. Nonetheless, an instance or two of hail is possible, along with severe gusts, especially with multicellular cold-pool mergers. ...Coastal Carolinas... A tropical storm is forecast to make landfall along the Carolina coastline at the start of the Day 2 period/12Z Sunday (please see the National Hurricane Center's advisories for more information on the progression of Tropical Depression 3). A deeply moist troposphere will accompany the land-falling TC, with MLCAPE approaching the 750-1000 J/kg range. Nonetheless, the vertical wind fields associated with this land-falling tropical storm are expected to quickly weaken, along with vertical wind shear. As such, while the risk for a brief tornado is technically non-zero, confidence in any robust tornado coverage is too low for the introduction of 2 percent or greater tornado probabilities at this time. ..Squitieri.. 07/05/2025 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1255 AM CDT Sat Jul 05 2025 Valid 061200Z - 071200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE CENTRAL HIGH PLAINS... ...SUMMARY... Storms may produce severe wind and hail along the central High Plains tomorrow (Sunday). A few instances of 2+ inch diameter hail and 75+ mph wind gusts are possible. ...Synopsis... Mainly zonal upper flow will become established over the northern CONUS, with multiple embedded impulses poised to traverse the zonal flow through the day tomorrow (Sunday). The best chance for strong storms will be associated with mid-level impulses impinging on the High Plains and New England Sunday afternoon. Ample moisture and associated instability will precede the impulses, that combined with adequate vertical wind shear, will support storm organization, some of which could be severe. ...Maine... A belt of 50 kt westerly 500 mb flow will overspread southeast Quebec into Maine Sunday afternoon with the overhead passage of a mid-level impulse. Surface lee troughing over Maine will serve as an impetus for thunderstorm initiation during the afternoon, when surface temperatures/dewpoints in the low 80s/upper 60s F will boost MLCAPE to over 1000 J/kg. Modestly curved, sizeable low-level hodographs suggest that multicells and supercells will be the main storm mode, possibly accompanied by damaging gusts. ...Central and Southern High Plains... Low-level upslope flow will encourage the northwestward advection of 60s F surface dewpoints into the higher terrain of the High Plains Sunday afternoon, beneath 8-9 C/km 700-500 mb lapse rates. Moderate to strong instability will manifest, with over 3000 J/kg MLCAPE possible. Storms will initiate over the higher terrain, amid straight hodographs, contributing to splitting supercell potential. By evening, the southeasterly surface flow will be overspread by a strengthening southerly low-level jet, with flow quickly veering to westerly in the 700-500 mb layer. This directional shear will support curved low-level hodographs with continued supercell potential, before storms merge into an MCS by evening. While in the supercell phase, a few instances of severe hail (perhaps an instance or two of 2+ inch diameter hail) are possible, along with severe gusts and perhaps a tornado. By the time storms merge into an MCS, severe gusts will become the primary threat, and a few gusts exceeding 75 mph will be possible. Higher severe probabilities may be needed if confidence increases in a longer-lived, severe-wind producing MCS developing. Farther south into the southern High Plains, storm coverage should be relatively less, with multicells becoming outflow dominant more quickly given weaker vertical wind shear compared to the central High Plains. Nonetheless, an instance or two of hail is possible, along with severe gusts, especially with multicellular cold-pool mergers. ...Coastal Carolinas... A tropical storm is forecast to make landfall along the Carolina coastline at the start of the Day 2 period/12Z Sunday (please see the National Hurricane Center's advisories for more information on the progression of Tropical Depression 3). A deeply moist troposphere will accompany the land-falling TC, with MLCAPE approaching the 750-1000 J/kg range. Nonetheless, the vertical wind fields associated with this land-falling tropical storm are expected to quickly weaken, along with vertical wind shear. As such, while the risk for a brief tornado is technically non-zero, confidence in any robust tornado coverage is too low for the introduction of 2 percent or greater tornado probabilities at this time. ..Squitieri.. 07/05/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1252 AM CDT Sat Jul 05 2025 Valid 051200Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF THE NORTHERN HIGH PLAINS... ...SUMMARY... Scattered severe storms are likely across portions of the northern High Plains, with severe winds and large hail being the main concerns. Isolated damaging gusts may also accompany the stronger storms over the Upper Midwest. ...Northern High Plains... A progressive midlevel wave and accompanying 40-50-kt jet streak will overspread the northern High Plains from the late afternoon into the evening/overnight hours. In the low-levels, a corridor of middle/upper 50s dewpoints will extend westward into the northern High Plains, beneath steepening midlevel lapse rates accompanying the midlevel wave. As scattered thunderstorms spread eastward across central/eastern MT and northern WY into this corridor, 40-50 kt of effective shear will favor intensification into semi-discrete supercells and organized clusters. Established supercells will pose a risk of large hail and locally severe wind gusts, while any upscale-growing clusters will be capable of producing severe wind gusts (some 75+ mph). ...Upper Midwest into the central Plains... A separate midlevel trough will move eastward across the Upper Midwest, while a related cold front advances southeastward across the Upper Midwest and Lower MO Valley during the day. Despite poor midlevel lapse rates, rich boundary-layer moisture and a belt of enhanced low/midlevel flow will support a few strong to severe storms capable of damaging gusts along/ahead of the front. ...Southern High Plains... Scattered thunderstorm development is expected along the higher terrain during the afternoon, before spreading east-southeastward into the evening/overnight hours. Steep deep-layer lapse rates and moderate northwesterly flow aloft will favor several loosely organized clusters capable of producing severe wind gusts and large hail. ..Weinman/Supinie.. 07/05/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1252 AM CDT Sat Jul 05 2025 Valid 051200Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF THE NORTHERN HIGH PLAINS... ...SUMMARY... Scattered severe storms are likely across portions of the northern High Plains, with severe winds and large hail being the main concerns. Isolated damaging gusts may also accompany the stronger storms over the Upper Midwest. ...Northern High Plains... A progressive midlevel wave and accompanying 40-50-kt jet streak will overspread the northern High Plains from the late afternoon into the evening/overnight hours. In the low-levels, a corridor of middle/upper 50s dewpoints will extend westward into the northern High Plains, beneath steepening midlevel lapse rates accompanying the midlevel wave. As scattered thunderstorms spread eastward across central/eastern MT and northern WY into this corridor, 40-50 kt of effective shear will favor intensification into semi-discrete supercells and organized clusters. Established supercells will pose a risk of large hail and locally severe wind gusts, while any upscale-growing clusters will be capable of producing severe wind gusts (some 75+ mph). ...Upper Midwest into the central Plains... A separate midlevel trough will move eastward across the Upper Midwest, while a related cold front advances southeastward across the Upper Midwest and Lower MO Valley during the day. Despite poor midlevel lapse rates, rich boundary-layer moisture and a belt of enhanced low/midlevel flow will support a few strong to severe storms capable of damaging gusts along/ahead of the front. ...Southern High Plains... Scattered thunderstorm development is expected along the higher terrain during the afternoon, before spreading east-southeastward into the evening/overnight hours. Steep deep-layer lapse rates and moderate northwesterly flow aloft will favor several loosely organized clusters capable of producing severe wind gusts and large hail. ..Weinman/Supinie.. 07/05/2025 Read more