Severe Storms

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1153 AM CDT Fri Jun 14 2024 Valid 141700Z - 151200Z The previous discussion is largely on track. With the mid-level trough near the Four Corners moving to the east, the risk for isolated dry thunderstorms has been shifted east accordingly. Additionally, some locally elevated conditions are possible along the lee of the northern California coastal ranges, with guidance depicting some potential for terrain-enhanced downslope flow with near-critical values of RH. However, fuels in the area are not particularly dry, so will decline to introduce highlights. ..Supinie.. 06/14/2024 .PREV DISCUSSION... /ISSUED 0153 AM CDT Fri Jun 14 2024/ ...Synopsis... A midlevel trough and belt of south-southwesterly flow aloft will advance east-northeastward across the Southwest on Friday. A surface low south of south-central NM will promote modestly breezy westerly surface winds across southeastern AZ and southwestern NM. Given a deep/dry boundary layer across the area (single-digit RH), elevated to locally critical fire-weather conditions are expected. The primary limiting factor for the addition of a Critical area continues to be marginal surface winds (15-20 mph). Across northern Arizona on the fringe of better moisture located across the Four Corners into western New Mexico, isolated dry thunderstorms will be possible along the Mogollon Rim. Enhanced westerly flow aloft will move into the base of a mid-level trough across the Northwest Friday afternoon. The associated downslope flow across the Cascades and Sierra will favor locally dry/breezy conditions across portions of northwestern NV and eastern WA/northeastern OR where fuels have dried sufficiently to support fire spread. As a result, elevated conditions are expected for both areas, with locally critical conditions possible in northwestern NV -- where 20-25 mph sustained westerly surface winds are expected. ...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 1153 AM CDT Fri Jun 14 2024 Valid 141700Z - 151200Z The previous discussion is largely on track. With the mid-level trough near the Four Corners moving to the east, the risk for isolated dry thunderstorms has been shifted east accordingly. Additionally, some locally elevated conditions are possible along the lee of the northern California coastal ranges, with guidance depicting some potential for terrain-enhanced downslope flow with near-critical values of RH. However, fuels in the area are not particularly dry, so will decline to introduce highlights. ..Supinie.. 06/14/2024 .PREV DISCUSSION... /ISSUED 0153 AM CDT Fri Jun 14 2024/ ...Synopsis... A midlevel trough and belt of south-southwesterly flow aloft will advance east-northeastward across the Southwest on Friday. A surface low south of south-central NM will promote modestly breezy westerly surface winds across southeastern AZ and southwestern NM. Given a deep/dry boundary layer across the area (single-digit RH), elevated to locally critical fire-weather conditions are expected. The primary limiting factor for the addition of a Critical area continues to be marginal surface winds (15-20 mph). Across northern Arizona on the fringe of better moisture located across the Four Corners into western New Mexico, isolated dry thunderstorms will be possible along the Mogollon Rim. Enhanced westerly flow aloft will move into the base of a mid-level trough across the Northwest Friday afternoon. The associated downslope flow across the Cascades and Sierra will favor locally dry/breezy conditions across portions of northwestern NV and eastern WA/northeastern OR where fuels have dried sufficiently to support fire spread. As a result, elevated conditions are expected for both areas, with locally critical conditions possible in northwestern NV -- where 20-25 mph sustained westerly surface winds are expected. ...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 1153 AM CDT Fri Jun 14 2024 Valid 141700Z - 151200Z The previous discussion is largely on track. With the mid-level trough near the Four Corners moving to the east, the risk for isolated dry thunderstorms has been shifted east accordingly. Additionally, some locally elevated conditions are possible along the lee of the northern California coastal ranges, with guidance depicting some potential for terrain-enhanced downslope flow with near-critical values of RH. However, fuels in the area are not particularly dry, so will decline to introduce highlights. ..Supinie.. 06/14/2024 .PREV DISCUSSION... /ISSUED 0153 AM CDT Fri Jun 14 2024/ ...Synopsis... A midlevel trough and belt of south-southwesterly flow aloft will advance east-northeastward across the Southwest on Friday. A surface low south of south-central NM will promote modestly breezy westerly surface winds across southeastern AZ and southwestern NM. Given a deep/dry boundary layer across the area (single-digit RH), elevated to locally critical fire-weather conditions are expected. The primary limiting factor for the addition of a Critical area continues to be marginal surface winds (15-20 mph). Across northern Arizona on the fringe of better moisture located across the Four Corners into western New Mexico, isolated dry thunderstorms will be possible along the Mogollon Rim. Enhanced westerly flow aloft will move into the base of a mid-level trough across the Northwest Friday afternoon. The associated downslope flow across the Cascades and Sierra will favor locally dry/breezy conditions across portions of northwestern NV and eastern WA/northeastern OR where fuels have dried sufficiently to support fire spread. As a result, elevated conditions are expected for both areas, with locally critical conditions possible in northwestern NV -- where 20-25 mph sustained westerly surface winds are expected. ...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 1153 AM CDT Fri Jun 14 2024 Valid 141700Z - 151200Z The previous discussion is largely on track. With the mid-level trough near the Four Corners moving to the east, the risk for isolated dry thunderstorms has been shifted east accordingly. Additionally, some locally elevated conditions are possible along the lee of the northern California coastal ranges, with guidance depicting some potential for terrain-enhanced downslope flow with near-critical values of RH. However, fuels in the area are not particularly dry, so will decline to introduce highlights. ..Supinie.. 06/14/2024 .PREV DISCUSSION... /ISSUED 0153 AM CDT Fri Jun 14 2024/ ...Synopsis... A midlevel trough and belt of south-southwesterly flow aloft will advance east-northeastward across the Southwest on Friday. A surface low south of south-central NM will promote modestly breezy westerly surface winds across southeastern AZ and southwestern NM. Given a deep/dry boundary layer across the area (single-digit RH), elevated to locally critical fire-weather conditions are expected. The primary limiting factor for the addition of a Critical area continues to be marginal surface winds (15-20 mph). Across northern Arizona on the fringe of better moisture located across the Four Corners into western New Mexico, isolated dry thunderstorms will be possible along the Mogollon Rim. Enhanced westerly flow aloft will move into the base of a mid-level trough across the Northwest Friday afternoon. The associated downslope flow across the Cascades and Sierra will favor locally dry/breezy conditions across portions of northwestern NV and eastern WA/northeastern OR where fuels have dried sufficiently to support fire spread. As a result, elevated conditions are expected for both areas, with locally critical conditions possible in northwestern NV -- where 20-25 mph sustained westerly surface winds are expected. ...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 1153 AM CDT Fri Jun 14 2024 Valid 141700Z - 151200Z The previous discussion is largely on track. With the mid-level trough near the Four Corners moving to the east, the risk for isolated dry thunderstorms has been shifted east accordingly. Additionally, some locally elevated conditions are possible along the lee of the northern California coastal ranges, with guidance depicting some potential for terrain-enhanced downslope flow with near-critical values of RH. However, fuels in the area are not particularly dry, so will decline to introduce highlights. ..Supinie.. 06/14/2024 .PREV DISCUSSION... /ISSUED 0153 AM CDT Fri Jun 14 2024/ ...Synopsis... A midlevel trough and belt of south-southwesterly flow aloft will advance east-northeastward across the Southwest on Friday. A surface low south of south-central NM will promote modestly breezy westerly surface winds across southeastern AZ and southwestern NM. Given a deep/dry boundary layer across the area (single-digit RH), elevated to locally critical fire-weather conditions are expected. The primary limiting factor for the addition of a Critical area continues to be marginal surface winds (15-20 mph). Across northern Arizona on the fringe of better moisture located across the Four Corners into western New Mexico, isolated dry thunderstorms will be possible along the Mogollon Rim. Enhanced westerly flow aloft will move into the base of a mid-level trough across the Northwest Friday afternoon. The associated downslope flow across the Cascades and Sierra will favor locally dry/breezy conditions across portions of northwestern NV and eastern WA/northeastern OR where fuels have dried sufficiently to support fire spread. As a result, elevated conditions are expected for both areas, with locally critical conditions possible in northwestern NV -- where 20-25 mph sustained westerly surface winds are expected. ...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 1153 AM CDT Fri Jun 14 2024 Valid 141700Z - 151200Z The previous discussion is largely on track. With the mid-level trough near the Four Corners moving to the east, the risk for isolated dry thunderstorms has been shifted east accordingly. Additionally, some locally elevated conditions are possible along the lee of the northern California coastal ranges, with guidance depicting some potential for terrain-enhanced downslope flow with near-critical values of RH. However, fuels in the area are not particularly dry, so will decline to introduce highlights. ..Supinie.. 06/14/2024 .PREV DISCUSSION... /ISSUED 0153 AM CDT Fri Jun 14 2024/ ...Synopsis... A midlevel trough and belt of south-southwesterly flow aloft will advance east-northeastward across the Southwest on Friday. A surface low south of south-central NM will promote modestly breezy westerly surface winds across southeastern AZ and southwestern NM. Given a deep/dry boundary layer across the area (single-digit RH), elevated to locally critical fire-weather conditions are expected. The primary limiting factor for the addition of a Critical area continues to be marginal surface winds (15-20 mph). Across northern Arizona on the fringe of better moisture located across the Four Corners into western New Mexico, isolated dry thunderstorms will be possible along the Mogollon Rim. Enhanced westerly flow aloft will move into the base of a mid-level trough across the Northwest Friday afternoon. The associated downslope flow across the Cascades and Sierra will favor locally dry/breezy conditions across portions of northwestern NV and eastern WA/northeastern OR where fuels have dried sufficiently to support fire spread. As a result, elevated conditions are expected for both areas, with locally critical conditions possible in northwestern NV -- where 20-25 mph sustained westerly surface winds are expected. ...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 1153 AM CDT Fri Jun 14 2024 Valid 141700Z - 151200Z The previous discussion is largely on track. With the mid-level trough near the Four Corners moving to the east, the risk for isolated dry thunderstorms has been shifted east accordingly. Additionally, some locally elevated conditions are possible along the lee of the northern California coastal ranges, with guidance depicting some potential for terrain-enhanced downslope flow with near-critical values of RH. However, fuels in the area are not particularly dry, so will decline to introduce highlights. ..Supinie.. 06/14/2024 .PREV DISCUSSION... /ISSUED 0153 AM CDT Fri Jun 14 2024/ ...Synopsis... A midlevel trough and belt of south-southwesterly flow aloft will advance east-northeastward across the Southwest on Friday. A surface low south of south-central NM will promote modestly breezy westerly surface winds across southeastern AZ and southwestern NM. Given a deep/dry boundary layer across the area (single-digit RH), elevated to locally critical fire-weather conditions are expected. The primary limiting factor for the addition of a Critical area continues to be marginal surface winds (15-20 mph). Across northern Arizona on the fringe of better moisture located across the Four Corners into western New Mexico, isolated dry thunderstorms will be possible along the Mogollon Rim. Enhanced westerly flow aloft will move into the base of a mid-level trough across the Northwest Friday afternoon. The associated downslope flow across the Cascades and Sierra will favor locally dry/breezy conditions across portions of northwestern NV and eastern WA/northeastern OR where fuels have dried sufficiently to support fire spread. As a result, elevated conditions are expected for both areas, with locally critical conditions possible in northwestern NV -- where 20-25 mph sustained westerly surface winds are expected. ...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 1153 AM CDT Fri Jun 14 2024 Valid 141700Z - 151200Z The previous discussion is largely on track. With the mid-level trough near the Four Corners moving to the east, the risk for isolated dry thunderstorms has been shifted east accordingly. Additionally, some locally elevated conditions are possible along the lee of the northern California coastal ranges, with guidance depicting some potential for terrain-enhanced downslope flow with near-critical values of RH. However, fuels in the area are not particularly dry, so will decline to introduce highlights. ..Supinie.. 06/14/2024 .PREV DISCUSSION... /ISSUED 0153 AM CDT Fri Jun 14 2024/ ...Synopsis... A midlevel trough and belt of south-southwesterly flow aloft will advance east-northeastward across the Southwest on Friday. A surface low south of south-central NM will promote modestly breezy westerly surface winds across southeastern AZ and southwestern NM. Given a deep/dry boundary layer across the area (single-digit RH), elevated to locally critical fire-weather conditions are expected. The primary limiting factor for the addition of a Critical area continues to be marginal surface winds (15-20 mph). Across northern Arizona on the fringe of better moisture located across the Four Corners into western New Mexico, isolated dry thunderstorms will be possible along the Mogollon Rim. Enhanced westerly flow aloft will move into the base of a mid-level trough across the Northwest Friday afternoon. The associated downslope flow across the Cascades and Sierra will favor locally dry/breezy conditions across portions of northwestern NV and eastern WA/northeastern OR where fuels have dried sufficiently to support fire spread. As a result, elevated conditions are expected for both areas, with locally critical conditions possible in northwestern NV -- where 20-25 mph sustained westerly surface winds are expected. ...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 1153 AM CDT Fri Jun 14 2024 Valid 141700Z - 151200Z The previous discussion is largely on track. With the mid-level trough near the Four Corners moving to the east, the risk for isolated dry thunderstorms has been shifted east accordingly. Additionally, some locally elevated conditions are possible along the lee of the northern California coastal ranges, with guidance depicting some potential for terrain-enhanced downslope flow with near-critical values of RH. However, fuels in the area are not particularly dry, so will decline to introduce highlights. ..Supinie.. 06/14/2024 .PREV DISCUSSION... /ISSUED 0153 AM CDT Fri Jun 14 2024/ ...Synopsis... A midlevel trough and belt of south-southwesterly flow aloft will advance east-northeastward across the Southwest on Friday. A surface low south of south-central NM will promote modestly breezy westerly surface winds across southeastern AZ and southwestern NM. Given a deep/dry boundary layer across the area (single-digit RH), elevated to locally critical fire-weather conditions are expected. The primary limiting factor for the addition of a Critical area continues to be marginal surface winds (15-20 mph). Across northern Arizona on the fringe of better moisture located across the Four Corners into western New Mexico, isolated dry thunderstorms will be possible along the Mogollon Rim. Enhanced westerly flow aloft will move into the base of a mid-level trough across the Northwest Friday afternoon. The associated downslope flow across the Cascades and Sierra will favor locally dry/breezy conditions across portions of northwestern NV and eastern WA/northeastern OR where fuels have dried sufficiently to support fire spread. As a result, elevated conditions are expected for both areas, with locally critical conditions possible in northwestern NV -- where 20-25 mph sustained westerly surface winds are expected. ...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 1153 AM CDT Fri Jun 14 2024 Valid 141700Z - 151200Z The previous discussion is largely on track. With the mid-level trough near the Four Corners moving to the east, the risk for isolated dry thunderstorms has been shifted east accordingly. Additionally, some locally elevated conditions are possible along the lee of the northern California coastal ranges, with guidance depicting some potential for terrain-enhanced downslope flow with near-critical values of RH. However, fuels in the area are not particularly dry, so will decline to introduce highlights. ..Supinie.. 06/14/2024 .PREV DISCUSSION... /ISSUED 0153 AM CDT Fri Jun 14 2024/ ...Synopsis... A midlevel trough and belt of south-southwesterly flow aloft will advance east-northeastward across the Southwest on Friday. A surface low south of south-central NM will promote modestly breezy westerly surface winds across southeastern AZ and southwestern NM. Given a deep/dry boundary layer across the area (single-digit RH), elevated to locally critical fire-weather conditions are expected. The primary limiting factor for the addition of a Critical area continues to be marginal surface winds (15-20 mph). Across northern Arizona on the fringe of better moisture located across the Four Corners into western New Mexico, isolated dry thunderstorms will be possible along the Mogollon Rim. Enhanced westerly flow aloft will move into the base of a mid-level trough across the Northwest Friday afternoon. The associated downslope flow across the Cascades and Sierra will favor locally dry/breezy conditions across portions of northwestern NV and eastern WA/northeastern OR where fuels have dried sufficiently to support fire spread. As a result, elevated conditions are expected for both areas, with locally critical conditions possible in northwestern NV -- where 20-25 mph sustained westerly surface winds are expected. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Fri Jun 14 2024 Valid 141630Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS...AND NORTHEAST/MID-ATLANTIC... ...SUMMARY... Scattered severe thunderstorms with large hail and wind gusts around 60-80 mph will be possible from mid-afternoon through this evening along the Front Range to the central Great Plains. Scattered strong to severe thunderstorms with occasional damaging winds and isolated hail will also be possible across parts of the Northeast and Mid-Atlantic during the afternoon to early evening. ...Central Plains... A mid-level shortwave trough over the Southwest will continue northeastward today towards the central Rockies/Plains. Post-frontal, low-level easterly upslope flow is ongoing across the central High Plains to the Front Range in eastern CO. A somewhat moist-level airmass is present across this area, and robust daytime heating is forecast with little cloud cover present on recent visible satellite imagery. Initially high-based thunderstorms should form over the central Rockies as forcing aloft overspreads this region. Modest, but sufficient, mid-level flow attendant to the shortwave trough and related deep-layer shear should support some updraft organization and a threat for severe hail with more discrete cells initially. A fairly quick evolution/upscale growth into a loosely organized cluster still appears likely as convection spreads east-northeastward into the central High Plains later this afternoon and early evening. An increasing threat for severe/damaging winds around 60-70 mph should materialize as this mode transition occurs. As low-level lapse rates become steepened with robust heating, and the boundary layer becomes very well mixed, some risk for isolated significant severe gusts (75-80 mph) may develop. This risk appears relatively greatest across parts of eastern CO into adjacent portions of western KS/NE. Late this evening, the cluster should eventually encounter a less unstable airmass with eastward extent across the central Plains, and subsequently weaken. ...Northern Plains/Rockies... Diurnal destabilization should occur today near/east of a weak surface low across the northern High Plains, with modest instability extending westward across parts of the northern Rockies. Isolated to widely scattered thunderstorms should form by late afternoon into the evening, with sufficient deep-layer shear to support isolated stronger storms capable of producing occasional hail and strong-to-severe wind gusts. This threat should tend to remain fairly isolated/marginal. ...Northeast/Mid-Atlantic... Recent visible satellite imagery shows cloud cover remains prevalent across parts of the Northeast and Mid-Atlantic ahead of a cold front. This should tend to delay/mute daytime heating to some extent, especially with northward extent into New England. Even so, filtered diurnal heating, and less cloud cover southward into the Mid-Atlantic, will support modest destabilization. Most guidance continues to suggest that MLCAPE will generally reach around 500-1000 J/kg by mid afternoon ahead of the front. Current expectations are for thunderstorms to gradually increase in coverage and intensity across these areas this afternoon as the front continues eastward in tandem with a mid/upper-level trough over eastern Canada. With around 30-40 kt of deep-layer shear available to support updraft organization, occasional damaging winds should be the primary threat with any clusters or short line segments that can develop. Isolated hail may also occur with initially more discrete activity. This activity is forecast to spread eastward through the afternoon and early evening, before eventually weakening and/or reaching the coast. Additional convection may form this afternoon along the trailing portion of the cold front in western PA, northern WV, and southeast/central OH. An embedded, low-amplitude mid-level shortwave trough over the Great Lakes/Upper Midwest may aid this development, along with modest low-level convergence along the front. Overall thunderstorm coverage is still somewhat uncertain with westward extent into the OH Valley. But, isolated to widely scattered thunderstorms, including a mix of a couple of supercells and small clusters with associated hail/wind threat, support a westward expansion of the Slight Risk to account for this potential. ..Gleason/Barnes.. 06/14/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Fri Jun 14 2024 Valid 141630Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS...AND NORTHEAST/MID-ATLANTIC... ...SUMMARY... Scattered severe thunderstorms with large hail and wind gusts around 60-80 mph will be possible from mid-afternoon through this evening along the Front Range to the central Great Plains. Scattered strong to severe thunderstorms with occasional damaging winds and isolated hail will also be possible across parts of the Northeast and Mid-Atlantic during the afternoon to early evening. ...Central Plains... A mid-level shortwave trough over the Southwest will continue northeastward today towards the central Rockies/Plains. Post-frontal, low-level easterly upslope flow is ongoing across the central High Plains to the Front Range in eastern CO. A somewhat moist-level airmass is present across this area, and robust daytime heating is forecast with little cloud cover present on recent visible satellite imagery. Initially high-based thunderstorms should form over the central Rockies as forcing aloft overspreads this region. Modest, but sufficient, mid-level flow attendant to the shortwave trough and related deep-layer shear should support some updraft organization and a threat for severe hail with more discrete cells initially. A fairly quick evolution/upscale growth into a loosely organized cluster still appears likely as convection spreads east-northeastward into the central High Plains later this afternoon and early evening. An increasing threat for severe/damaging winds around 60-70 mph should materialize as this mode transition occurs. As low-level lapse rates become steepened with robust heating, and the boundary layer becomes very well mixed, some risk for isolated significant severe gusts (75-80 mph) may develop. This risk appears relatively greatest across parts of eastern CO into adjacent portions of western KS/NE. Late this evening, the cluster should eventually encounter a less unstable airmass with eastward extent across the central Plains, and subsequently weaken. ...Northern Plains/Rockies... Diurnal destabilization should occur today near/east of a weak surface low across the northern High Plains, with modest instability extending westward across parts of the northern Rockies. Isolated to widely scattered thunderstorms should form by late afternoon into the evening, with sufficient deep-layer shear to support isolated stronger storms capable of producing occasional hail and strong-to-severe wind gusts. This threat should tend to remain fairly isolated/marginal. ...Northeast/Mid-Atlantic... Recent visible satellite imagery shows cloud cover remains prevalent across parts of the Northeast and Mid-Atlantic ahead of a cold front. This should tend to delay/mute daytime heating to some extent, especially with northward extent into New England. Even so, filtered diurnal heating, and less cloud cover southward into the Mid-Atlantic, will support modest destabilization. Most guidance continues to suggest that MLCAPE will generally reach around 500-1000 J/kg by mid afternoon ahead of the front. Current expectations are for thunderstorms to gradually increase in coverage and intensity across these areas this afternoon as the front continues eastward in tandem with a mid/upper-level trough over eastern Canada. With around 30-40 kt of deep-layer shear available to support updraft organization, occasional damaging winds should be the primary threat with any clusters or short line segments that can develop. Isolated hail may also occur with initially more discrete activity. This activity is forecast to spread eastward through the afternoon and early evening, before eventually weakening and/or reaching the coast. Additional convection may form this afternoon along the trailing portion of the cold front in western PA, northern WV, and southeast/central OH. An embedded, low-amplitude mid-level shortwave trough over the Great Lakes/Upper Midwest may aid this development, along with modest low-level convergence along the front. Overall thunderstorm coverage is still somewhat uncertain with westward extent into the OH Valley. But, isolated to widely scattered thunderstorms, including a mix of a couple of supercells and small clusters with associated hail/wind threat, support a westward expansion of the Slight Risk to account for this potential. ..Gleason/Barnes.. 06/14/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Fri Jun 14 2024 Valid 141630Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS...AND NORTHEAST/MID-ATLANTIC... ...SUMMARY... Scattered severe thunderstorms with large hail and wind gusts around 60-80 mph will be possible from mid-afternoon through this evening along the Front Range to the central Great Plains. Scattered strong to severe thunderstorms with occasional damaging winds and isolated hail will also be possible across parts of the Northeast and Mid-Atlantic during the afternoon to early evening. ...Central Plains... A mid-level shortwave trough over the Southwest will continue northeastward today towards the central Rockies/Plains. Post-frontal, low-level easterly upslope flow is ongoing across the central High Plains to the Front Range in eastern CO. A somewhat moist-level airmass is present across this area, and robust daytime heating is forecast with little cloud cover present on recent visible satellite imagery. Initially high-based thunderstorms should form over the central Rockies as forcing aloft overspreads this region. Modest, but sufficient, mid-level flow attendant to the shortwave trough and related deep-layer shear should support some updraft organization and a threat for severe hail with more discrete cells initially. A fairly quick evolution/upscale growth into a loosely organized cluster still appears likely as convection spreads east-northeastward into the central High Plains later this afternoon and early evening. An increasing threat for severe/damaging winds around 60-70 mph should materialize as this mode transition occurs. As low-level lapse rates become steepened with robust heating, and the boundary layer becomes very well mixed, some risk for isolated significant severe gusts (75-80 mph) may develop. This risk appears relatively greatest across parts of eastern CO into adjacent portions of western KS/NE. Late this evening, the cluster should eventually encounter a less unstable airmass with eastward extent across the central Plains, and subsequently weaken. ...Northern Plains/Rockies... Diurnal destabilization should occur today near/east of a weak surface low across the northern High Plains, with modest instability extending westward across parts of the northern Rockies. Isolated to widely scattered thunderstorms should form by late afternoon into the evening, with sufficient deep-layer shear to support isolated stronger storms capable of producing occasional hail and strong-to-severe wind gusts. This threat should tend to remain fairly isolated/marginal. ...Northeast/Mid-Atlantic... Recent visible satellite imagery shows cloud cover remains prevalent across parts of the Northeast and Mid-Atlantic ahead of a cold front. This should tend to delay/mute daytime heating to some extent, especially with northward extent into New England. Even so, filtered diurnal heating, and less cloud cover southward into the Mid-Atlantic, will support modest destabilization. Most guidance continues to suggest that MLCAPE will generally reach around 500-1000 J/kg by mid afternoon ahead of the front. Current expectations are for thunderstorms to gradually increase in coverage and intensity across these areas this afternoon as the front continues eastward in tandem with a mid/upper-level trough over eastern Canada. With around 30-40 kt of deep-layer shear available to support updraft organization, occasional damaging winds should be the primary threat with any clusters or short line segments that can develop. Isolated hail may also occur with initially more discrete activity. This activity is forecast to spread eastward through the afternoon and early evening, before eventually weakening and/or reaching the coast. Additional convection may form this afternoon along the trailing portion of the cold front in western PA, northern WV, and southeast/central OH. An embedded, low-amplitude mid-level shortwave trough over the Great Lakes/Upper Midwest may aid this development, along with modest low-level convergence along the front. Overall thunderstorm coverage is still somewhat uncertain with westward extent into the OH Valley. But, isolated to widely scattered thunderstorms, including a mix of a couple of supercells and small clusters with associated hail/wind threat, support a westward expansion of the Slight Risk to account for this potential. ..Gleason/Barnes.. 06/14/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Fri Jun 14 2024 Valid 141630Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS...AND NORTHEAST/MID-ATLANTIC... ...SUMMARY... Scattered severe thunderstorms with large hail and wind gusts around 60-80 mph will be possible from mid-afternoon through this evening along the Front Range to the central Great Plains. Scattered strong to severe thunderstorms with occasional damaging winds and isolated hail will also be possible across parts of the Northeast and Mid-Atlantic during the afternoon to early evening. ...Central Plains... A mid-level shortwave trough over the Southwest will continue northeastward today towards the central Rockies/Plains. Post-frontal, low-level easterly upslope flow is ongoing across the central High Plains to the Front Range in eastern CO. A somewhat moist-level airmass is present across this area, and robust daytime heating is forecast with little cloud cover present on recent visible satellite imagery. Initially high-based thunderstorms should form over the central Rockies as forcing aloft overspreads this region. Modest, but sufficient, mid-level flow attendant to the shortwave trough and related deep-layer shear should support some updraft organization and a threat for severe hail with more discrete cells initially. A fairly quick evolution/upscale growth into a loosely organized cluster still appears likely as convection spreads east-northeastward into the central High Plains later this afternoon and early evening. An increasing threat for severe/damaging winds around 60-70 mph should materialize as this mode transition occurs. As low-level lapse rates become steepened with robust heating, and the boundary layer becomes very well mixed, some risk for isolated significant severe gusts (75-80 mph) may develop. This risk appears relatively greatest across parts of eastern CO into adjacent portions of western KS/NE. Late this evening, the cluster should eventually encounter a less unstable airmass with eastward extent across the central Plains, and subsequently weaken. ...Northern Plains/Rockies... Diurnal destabilization should occur today near/east of a weak surface low across the northern High Plains, with modest instability extending westward across parts of the northern Rockies. Isolated to widely scattered thunderstorms should form by late afternoon into the evening, with sufficient deep-layer shear to support isolated stronger storms capable of producing occasional hail and strong-to-severe wind gusts. This threat should tend to remain fairly isolated/marginal. ...Northeast/Mid-Atlantic... Recent visible satellite imagery shows cloud cover remains prevalent across parts of the Northeast and Mid-Atlantic ahead of a cold front. This should tend to delay/mute daytime heating to some extent, especially with northward extent into New England. Even so, filtered diurnal heating, and less cloud cover southward into the Mid-Atlantic, will support modest destabilization. Most guidance continues to suggest that MLCAPE will generally reach around 500-1000 J/kg by mid afternoon ahead of the front. Current expectations are for thunderstorms to gradually increase in coverage and intensity across these areas this afternoon as the front continues eastward in tandem with a mid/upper-level trough over eastern Canada. With around 30-40 kt of deep-layer shear available to support updraft organization, occasional damaging winds should be the primary threat with any clusters or short line segments that can develop. Isolated hail may also occur with initially more discrete activity. This activity is forecast to spread eastward through the afternoon and early evening, before eventually weakening and/or reaching the coast. Additional convection may form this afternoon along the trailing portion of the cold front in western PA, northern WV, and southeast/central OH. An embedded, low-amplitude mid-level shortwave trough over the Great Lakes/Upper Midwest may aid this development, along with modest low-level convergence along the front. Overall thunderstorm coverage is still somewhat uncertain with westward extent into the OH Valley. But, isolated to widely scattered thunderstorms, including a mix of a couple of supercells and small clusters with associated hail/wind threat, support a westward expansion of the Slight Risk to account for this potential. ..Gleason/Barnes.. 06/14/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Fri Jun 14 2024 Valid 141630Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS...AND NORTHEAST/MID-ATLANTIC... ...SUMMARY... Scattered severe thunderstorms with large hail and wind gusts around 60-80 mph will be possible from mid-afternoon through this evening along the Front Range to the central Great Plains. Scattered strong to severe thunderstorms with occasional damaging winds and isolated hail will also be possible across parts of the Northeast and Mid-Atlantic during the afternoon to early evening. ...Central Plains... A mid-level shortwave trough over the Southwest will continue northeastward today towards the central Rockies/Plains. Post-frontal, low-level easterly upslope flow is ongoing across the central High Plains to the Front Range in eastern CO. A somewhat moist-level airmass is present across this area, and robust daytime heating is forecast with little cloud cover present on recent visible satellite imagery. Initially high-based thunderstorms should form over the central Rockies as forcing aloft overspreads this region. Modest, but sufficient, mid-level flow attendant to the shortwave trough and related deep-layer shear should support some updraft organization and a threat for severe hail with more discrete cells initially. A fairly quick evolution/upscale growth into a loosely organized cluster still appears likely as convection spreads east-northeastward into the central High Plains later this afternoon and early evening. An increasing threat for severe/damaging winds around 60-70 mph should materialize as this mode transition occurs. As low-level lapse rates become steepened with robust heating, and the boundary layer becomes very well mixed, some risk for isolated significant severe gusts (75-80 mph) may develop. This risk appears relatively greatest across parts of eastern CO into adjacent portions of western KS/NE. Late this evening, the cluster should eventually encounter a less unstable airmass with eastward extent across the central Plains, and subsequently weaken. ...Northern Plains/Rockies... Diurnal destabilization should occur today near/east of a weak surface low across the northern High Plains, with modest instability extending westward across parts of the northern Rockies. Isolated to widely scattered thunderstorms should form by late afternoon into the evening, with sufficient deep-layer shear to support isolated stronger storms capable of producing occasional hail and strong-to-severe wind gusts. This threat should tend to remain fairly isolated/marginal. ...Northeast/Mid-Atlantic... Recent visible satellite imagery shows cloud cover remains prevalent across parts of the Northeast and Mid-Atlantic ahead of a cold front. This should tend to delay/mute daytime heating to some extent, especially with northward extent into New England. Even so, filtered diurnal heating, and less cloud cover southward into the Mid-Atlantic, will support modest destabilization. Most guidance continues to suggest that MLCAPE will generally reach around 500-1000 J/kg by mid afternoon ahead of the front. Current expectations are for thunderstorms to gradually increase in coverage and intensity across these areas this afternoon as the front continues eastward in tandem with a mid/upper-level trough over eastern Canada. With around 30-40 kt of deep-layer shear available to support updraft organization, occasional damaging winds should be the primary threat with any clusters or short line segments that can develop. Isolated hail may also occur with initially more discrete activity. This activity is forecast to spread eastward through the afternoon and early evening, before eventually weakening and/or reaching the coast. Additional convection may form this afternoon along the trailing portion of the cold front in western PA, northern WV, and southeast/central OH. An embedded, low-amplitude mid-level shortwave trough over the Great Lakes/Upper Midwest may aid this development, along with modest low-level convergence along the front. Overall thunderstorm coverage is still somewhat uncertain with westward extent into the OH Valley. But, isolated to widely scattered thunderstorms, including a mix of a couple of supercells and small clusters with associated hail/wind threat, support a westward expansion of the Slight Risk to account for this potential. ..Gleason/Barnes.. 06/14/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Fri Jun 14 2024 Valid 141630Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS...AND NORTHEAST/MID-ATLANTIC... ...SUMMARY... Scattered severe thunderstorms with large hail and wind gusts around 60-80 mph will be possible from mid-afternoon through this evening along the Front Range to the central Great Plains. Scattered strong to severe thunderstorms with occasional damaging winds and isolated hail will also be possible across parts of the Northeast and Mid-Atlantic during the afternoon to early evening. ...Central Plains... A mid-level shortwave trough over the Southwest will continue northeastward today towards the central Rockies/Plains. Post-frontal, low-level easterly upslope flow is ongoing across the central High Plains to the Front Range in eastern CO. A somewhat moist-level airmass is present across this area, and robust daytime heating is forecast with little cloud cover present on recent visible satellite imagery. Initially high-based thunderstorms should form over the central Rockies as forcing aloft overspreads this region. Modest, but sufficient, mid-level flow attendant to the shortwave trough and related deep-layer shear should support some updraft organization and a threat for severe hail with more discrete cells initially. A fairly quick evolution/upscale growth into a loosely organized cluster still appears likely as convection spreads east-northeastward into the central High Plains later this afternoon and early evening. An increasing threat for severe/damaging winds around 60-70 mph should materialize as this mode transition occurs. As low-level lapse rates become steepened with robust heating, and the boundary layer becomes very well mixed, some risk for isolated significant severe gusts (75-80 mph) may develop. This risk appears relatively greatest across parts of eastern CO into adjacent portions of western KS/NE. Late this evening, the cluster should eventually encounter a less unstable airmass with eastward extent across the central Plains, and subsequently weaken. ...Northern Plains/Rockies... Diurnal destabilization should occur today near/east of a weak surface low across the northern High Plains, with modest instability extending westward across parts of the northern Rockies. Isolated to widely scattered thunderstorms should form by late afternoon into the evening, with sufficient deep-layer shear to support isolated stronger storms capable of producing occasional hail and strong-to-severe wind gusts. This threat should tend to remain fairly isolated/marginal. ...Northeast/Mid-Atlantic... Recent visible satellite imagery shows cloud cover remains prevalent across parts of the Northeast and Mid-Atlantic ahead of a cold front. This should tend to delay/mute daytime heating to some extent, especially with northward extent into New England. Even so, filtered diurnal heating, and less cloud cover southward into the Mid-Atlantic, will support modest destabilization. Most guidance continues to suggest that MLCAPE will generally reach around 500-1000 J/kg by mid afternoon ahead of the front. Current expectations are for thunderstorms to gradually increase in coverage and intensity across these areas this afternoon as the front continues eastward in tandem with a mid/upper-level trough over eastern Canada. With around 30-40 kt of deep-layer shear available to support updraft organization, occasional damaging winds should be the primary threat with any clusters or short line segments that can develop. Isolated hail may also occur with initially more discrete activity. This activity is forecast to spread eastward through the afternoon and early evening, before eventually weakening and/or reaching the coast. Additional convection may form this afternoon along the trailing portion of the cold front in western PA, northern WV, and southeast/central OH. An embedded, low-amplitude mid-level shortwave trough over the Great Lakes/Upper Midwest may aid this development, along with modest low-level convergence along the front. Overall thunderstorm coverage is still somewhat uncertain with westward extent into the OH Valley. But, isolated to widely scattered thunderstorms, including a mix of a couple of supercells and small clusters with associated hail/wind threat, support a westward expansion of the Slight Risk to account for this potential. ..Gleason/Barnes.. 06/14/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Fri Jun 14 2024 Valid 141630Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS...AND NORTHEAST/MID-ATLANTIC... ...SUMMARY... Scattered severe thunderstorms with large hail and wind gusts around 60-80 mph will be possible from mid-afternoon through this evening along the Front Range to the central Great Plains. Scattered strong to severe thunderstorms with occasional damaging winds and isolated hail will also be possible across parts of the Northeast and Mid-Atlantic during the afternoon to early evening. ...Central Plains... A mid-level shortwave trough over the Southwest will continue northeastward today towards the central Rockies/Plains. Post-frontal, low-level easterly upslope flow is ongoing across the central High Plains to the Front Range in eastern CO. A somewhat moist-level airmass is present across this area, and robust daytime heating is forecast with little cloud cover present on recent visible satellite imagery. Initially high-based thunderstorms should form over the central Rockies as forcing aloft overspreads this region. Modest, but sufficient, mid-level flow attendant to the shortwave trough and related deep-layer shear should support some updraft organization and a threat for severe hail with more discrete cells initially. A fairly quick evolution/upscale growth into a loosely organized cluster still appears likely as convection spreads east-northeastward into the central High Plains later this afternoon and early evening. An increasing threat for severe/damaging winds around 60-70 mph should materialize as this mode transition occurs. As low-level lapse rates become steepened with robust heating, and the boundary layer becomes very well mixed, some risk for isolated significant severe gusts (75-80 mph) may develop. This risk appears relatively greatest across parts of eastern CO into adjacent portions of western KS/NE. Late this evening, the cluster should eventually encounter a less unstable airmass with eastward extent across the central Plains, and subsequently weaken. ...Northern Plains/Rockies... Diurnal destabilization should occur today near/east of a weak surface low across the northern High Plains, with modest instability extending westward across parts of the northern Rockies. Isolated to widely scattered thunderstorms should form by late afternoon into the evening, with sufficient deep-layer shear to support isolated stronger storms capable of producing occasional hail and strong-to-severe wind gusts. This threat should tend to remain fairly isolated/marginal. ...Northeast/Mid-Atlantic... Recent visible satellite imagery shows cloud cover remains prevalent across parts of the Northeast and Mid-Atlantic ahead of a cold front. This should tend to delay/mute daytime heating to some extent, especially with northward extent into New England. Even so, filtered diurnal heating, and less cloud cover southward into the Mid-Atlantic, will support modest destabilization. Most guidance continues to suggest that MLCAPE will generally reach around 500-1000 J/kg by mid afternoon ahead of the front. Current expectations are for thunderstorms to gradually increase in coverage and intensity across these areas this afternoon as the front continues eastward in tandem with a mid/upper-level trough over eastern Canada. With around 30-40 kt of deep-layer shear available to support updraft organization, occasional damaging winds should be the primary threat with any clusters or short line segments that can develop. Isolated hail may also occur with initially more discrete activity. This activity is forecast to spread eastward through the afternoon and early evening, before eventually weakening and/or reaching the coast. Additional convection may form this afternoon along the trailing portion of the cold front in western PA, northern WV, and southeast/central OH. An embedded, low-amplitude mid-level shortwave trough over the Great Lakes/Upper Midwest may aid this development, along with modest low-level convergence along the front. Overall thunderstorm coverage is still somewhat uncertain with westward extent into the OH Valley. But, isolated to widely scattered thunderstorms, including a mix of a couple of supercells and small clusters with associated hail/wind threat, support a westward expansion of the Slight Risk to account for this potential. ..Gleason/Barnes.. 06/14/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Fri Jun 14 2024 Valid 141630Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS...AND NORTHEAST/MID-ATLANTIC... ...SUMMARY... Scattered severe thunderstorms with large hail and wind gusts around 60-80 mph will be possible from mid-afternoon through this evening along the Front Range to the central Great Plains. Scattered strong to severe thunderstorms with occasional damaging winds and isolated hail will also be possible across parts of the Northeast and Mid-Atlantic during the afternoon to early evening. ...Central Plains... A mid-level shortwave trough over the Southwest will continue northeastward today towards the central Rockies/Plains. Post-frontal, low-level easterly upslope flow is ongoing across the central High Plains to the Front Range in eastern CO. A somewhat moist-level airmass is present across this area, and robust daytime heating is forecast with little cloud cover present on recent visible satellite imagery. Initially high-based thunderstorms should form over the central Rockies as forcing aloft overspreads this region. Modest, but sufficient, mid-level flow attendant to the shortwave trough and related deep-layer shear should support some updraft organization and a threat for severe hail with more discrete cells initially. A fairly quick evolution/upscale growth into a loosely organized cluster still appears likely as convection spreads east-northeastward into the central High Plains later this afternoon and early evening. An increasing threat for severe/damaging winds around 60-70 mph should materialize as this mode transition occurs. As low-level lapse rates become steepened with robust heating, and the boundary layer becomes very well mixed, some risk for isolated significant severe gusts (75-80 mph) may develop. This risk appears relatively greatest across parts of eastern CO into adjacent portions of western KS/NE. Late this evening, the cluster should eventually encounter a less unstable airmass with eastward extent across the central Plains, and subsequently weaken. ...Northern Plains/Rockies... Diurnal destabilization should occur today near/east of a weak surface low across the northern High Plains, with modest instability extending westward across parts of the northern Rockies. Isolated to widely scattered thunderstorms should form by late afternoon into the evening, with sufficient deep-layer shear to support isolated stronger storms capable of producing occasional hail and strong-to-severe wind gusts. This threat should tend to remain fairly isolated/marginal. ...Northeast/Mid-Atlantic... Recent visible satellite imagery shows cloud cover remains prevalent across parts of the Northeast and Mid-Atlantic ahead of a cold front. This should tend to delay/mute daytime heating to some extent, especially with northward extent into New England. Even so, filtered diurnal heating, and less cloud cover southward into the Mid-Atlantic, will support modest destabilization. Most guidance continues to suggest that MLCAPE will generally reach around 500-1000 J/kg by mid afternoon ahead of the front. Current expectations are for thunderstorms to gradually increase in coverage and intensity across these areas this afternoon as the front continues eastward in tandem with a mid/upper-level trough over eastern Canada. With around 30-40 kt of deep-layer shear available to support updraft organization, occasional damaging winds should be the primary threat with any clusters or short line segments that can develop. Isolated hail may also occur with initially more discrete activity. This activity is forecast to spread eastward through the afternoon and early evening, before eventually weakening and/or reaching the coast. Additional convection may form this afternoon along the trailing portion of the cold front in western PA, northern WV, and southeast/central OH. An embedded, low-amplitude mid-level shortwave trough over the Great Lakes/Upper Midwest may aid this development, along with modest low-level convergence along the front. Overall thunderstorm coverage is still somewhat uncertain with westward extent into the OH Valley. But, isolated to widely scattered thunderstorms, including a mix of a couple of supercells and small clusters with associated hail/wind threat, support a westward expansion of the Slight Risk to account for this potential. ..Gleason/Barnes.. 06/14/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Fri Jun 14 2024 Valid 141630Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS...AND NORTHEAST/MID-ATLANTIC... ...SUMMARY... Scattered severe thunderstorms with large hail and wind gusts around 60-80 mph will be possible from mid-afternoon through this evening along the Front Range to the central Great Plains. Scattered strong to severe thunderstorms with occasional damaging winds and isolated hail will also be possible across parts of the Northeast and Mid-Atlantic during the afternoon to early evening. ...Central Plains... A mid-level shortwave trough over the Southwest will continue northeastward today towards the central Rockies/Plains. Post-frontal, low-level easterly upslope flow is ongoing across the central High Plains to the Front Range in eastern CO. A somewhat moist-level airmass is present across this area, and robust daytime heating is forecast with little cloud cover present on recent visible satellite imagery. Initially high-based thunderstorms should form over the central Rockies as forcing aloft overspreads this region. Modest, but sufficient, mid-level flow attendant to the shortwave trough and related deep-layer shear should support some updraft organization and a threat for severe hail with more discrete cells initially. A fairly quick evolution/upscale growth into a loosely organized cluster still appears likely as convection spreads east-northeastward into the central High Plains later this afternoon and early evening. An increasing threat for severe/damaging winds around 60-70 mph should materialize as this mode transition occurs. As low-level lapse rates become steepened with robust heating, and the boundary layer becomes very well mixed, some risk for isolated significant severe gusts (75-80 mph) may develop. This risk appears relatively greatest across parts of eastern CO into adjacent portions of western KS/NE. Late this evening, the cluster should eventually encounter a less unstable airmass with eastward extent across the central Plains, and subsequently weaken. ...Northern Plains/Rockies... Diurnal destabilization should occur today near/east of a weak surface low across the northern High Plains, with modest instability extending westward across parts of the northern Rockies. Isolated to widely scattered thunderstorms should form by late afternoon into the evening, with sufficient deep-layer shear to support isolated stronger storms capable of producing occasional hail and strong-to-severe wind gusts. This threat should tend to remain fairly isolated/marginal. ...Northeast/Mid-Atlantic... Recent visible satellite imagery shows cloud cover remains prevalent across parts of the Northeast and Mid-Atlantic ahead of a cold front. This should tend to delay/mute daytime heating to some extent, especially with northward extent into New England. Even so, filtered diurnal heating, and less cloud cover southward into the Mid-Atlantic, will support modest destabilization. Most guidance continues to suggest that MLCAPE will generally reach around 500-1000 J/kg by mid afternoon ahead of the front. Current expectations are for thunderstorms to gradually increase in coverage and intensity across these areas this afternoon as the front continues eastward in tandem with a mid/upper-level trough over eastern Canada. With around 30-40 kt of deep-layer shear available to support updraft organization, occasional damaging winds should be the primary threat with any clusters or short line segments that can develop. Isolated hail may also occur with initially more discrete activity. This activity is forecast to spread eastward through the afternoon and early evening, before eventually weakening and/or reaching the coast. Additional convection may form this afternoon along the trailing portion of the cold front in western PA, northern WV, and southeast/central OH. An embedded, low-amplitude mid-level shortwave trough over the Great Lakes/Upper Midwest may aid this development, along with modest low-level convergence along the front. Overall thunderstorm coverage is still somewhat uncertain with westward extent into the OH Valley. But, isolated to widely scattered thunderstorms, including a mix of a couple of supercells and small clusters with associated hail/wind threat, support a westward expansion of the Slight Risk to account for this potential. ..Gleason/Barnes.. 06/14/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Fri Jun 14 2024 Valid 141630Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS...AND NORTHEAST/MID-ATLANTIC... ...SUMMARY... Scattered severe thunderstorms with large hail and wind gusts around 60-80 mph will be possible from mid-afternoon through this evening along the Front Range to the central Great Plains. Scattered strong to severe thunderstorms with occasional damaging winds and isolated hail will also be possible across parts of the Northeast and Mid-Atlantic during the afternoon to early evening. ...Central Plains... A mid-level shortwave trough over the Southwest will continue northeastward today towards the central Rockies/Plains. Post-frontal, low-level easterly upslope flow is ongoing across the central High Plains to the Front Range in eastern CO. A somewhat moist-level airmass is present across this area, and robust daytime heating is forecast with little cloud cover present on recent visible satellite imagery. Initially high-based thunderstorms should form over the central Rockies as forcing aloft overspreads this region. Modest, but sufficient, mid-level flow attendant to the shortwave trough and related deep-layer shear should support some updraft organization and a threat for severe hail with more discrete cells initially. A fairly quick evolution/upscale growth into a loosely organized cluster still appears likely as convection spreads east-northeastward into the central High Plains later this afternoon and early evening. An increasing threat for severe/damaging winds around 60-70 mph should materialize as this mode transition occurs. As low-level lapse rates become steepened with robust heating, and the boundary layer becomes very well mixed, some risk for isolated significant severe gusts (75-80 mph) may develop. This risk appears relatively greatest across parts of eastern CO into adjacent portions of western KS/NE. Late this evening, the cluster should eventually encounter a less unstable airmass with eastward extent across the central Plains, and subsequently weaken. ...Northern Plains/Rockies... Diurnal destabilization should occur today near/east of a weak surface low across the northern High Plains, with modest instability extending westward across parts of the northern Rockies. Isolated to widely scattered thunderstorms should form by late afternoon into the evening, with sufficient deep-layer shear to support isolated stronger storms capable of producing occasional hail and strong-to-severe wind gusts. This threat should tend to remain fairly isolated/marginal. ...Northeast/Mid-Atlantic... Recent visible satellite imagery shows cloud cover remains prevalent across parts of the Northeast and Mid-Atlantic ahead of a cold front. This should tend to delay/mute daytime heating to some extent, especially with northward extent into New England. Even so, filtered diurnal heating, and less cloud cover southward into the Mid-Atlantic, will support modest destabilization. Most guidance continues to suggest that MLCAPE will generally reach around 500-1000 J/kg by mid afternoon ahead of the front. Current expectations are for thunderstorms to gradually increase in coverage and intensity across these areas this afternoon as the front continues eastward in tandem with a mid/upper-level trough over eastern Canada. With around 30-40 kt of deep-layer shear available to support updraft organization, occasional damaging winds should be the primary threat with any clusters or short line segments that can develop. Isolated hail may also occur with initially more discrete activity. This activity is forecast to spread eastward through the afternoon and early evening, before eventually weakening and/or reaching the coast. Additional convection may form this afternoon along the trailing portion of the cold front in western PA, northern WV, and southeast/central OH. An embedded, low-amplitude mid-level shortwave trough over the Great Lakes/Upper Midwest may aid this development, along with modest low-level convergence along the front. Overall thunderstorm coverage is still somewhat uncertain with westward extent into the OH Valley. But, isolated to widely scattered thunderstorms, including a mix of a couple of supercells and small clusters with associated hail/wind threat, support a westward expansion of the Slight Risk to account for this potential. ..Gleason/Barnes.. 06/14/2024 Read more