Severe Storms

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0246 PM CDT Fri Jun 14 2024 Valid 142000Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF CO/KS/NE AND THE UPPER OH VALLEY TO NEW ENGLAND... ...SUMMARY... Scattered severe thunderstorms with large hail and wind gusts around 60-80 mph will be possible through this evening along the Front Range to the central Great Plains. Scattered strong to locally severe storms with sporadic damaging winds and isolated hail will also be possible across parts of the Northeast and Mid-Atlantic through about dusk. ...20Z Update... Convection from New England to the Upper OH Valley has largely struggled to greatly intensify beyond a marginally severe status as of yet. Still, where boundary-layer warming has been more pronounced from parts of the Upper OH Valley, DE Valley, and southern to eastern New England, a few clusters may yet produce strong to localized severe gust before convection diminishes after dusk. The central states severe threat appears on-track. Deepening convection from the Sangre de Cristo Mountains northward along the Front Range should intensify as it impinges on the strengthening buoyancy plume over the central High Plains. For additional short-term information, see MCD 1262. ..Grams.. 06/14/2024 .PREV DISCUSSION... /ISSUED 1128 AM CDT Fri Jun 14 2024/ ...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. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0246 PM CDT Fri Jun 14 2024 Valid 142000Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF CO/KS/NE AND THE UPPER OH VALLEY TO NEW ENGLAND... ...SUMMARY... Scattered severe thunderstorms with large hail and wind gusts around 60-80 mph will be possible through this evening along the Front Range to the central Great Plains. Scattered strong to locally severe storms with sporadic damaging winds and isolated hail will also be possible across parts of the Northeast and Mid-Atlantic through about dusk. ...20Z Update... Convection from New England to the Upper OH Valley has largely struggled to greatly intensify beyond a marginally severe status as of yet. Still, where boundary-layer warming has been more pronounced from parts of the Upper OH Valley, DE Valley, and southern to eastern New England, a few clusters may yet produce strong to localized severe gust before convection diminishes after dusk. The central states severe threat appears on-track. Deepening convection from the Sangre de Cristo Mountains northward along the Front Range should intensify as it impinges on the strengthening buoyancy plume over the central High Plains. For additional short-term information, see MCD 1262. ..Grams.. 06/14/2024 .PREV DISCUSSION... /ISSUED 1128 AM CDT Fri Jun 14 2024/ ...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. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0246 PM CDT Fri Jun 14 2024 Valid 142000Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF CO/KS/NE AND THE UPPER OH VALLEY TO NEW ENGLAND... ...SUMMARY... Scattered severe thunderstorms with large hail and wind gusts around 60-80 mph will be possible through this evening along the Front Range to the central Great Plains. Scattered strong to locally severe storms with sporadic damaging winds and isolated hail will also be possible across parts of the Northeast and Mid-Atlantic through about dusk. ...20Z Update... Convection from New England to the Upper OH Valley has largely struggled to greatly intensify beyond a marginally severe status as of yet. Still, where boundary-layer warming has been more pronounced from parts of the Upper OH Valley, DE Valley, and southern to eastern New England, a few clusters may yet produce strong to localized severe gust before convection diminishes after dusk. The central states severe threat appears on-track. Deepening convection from the Sangre de Cristo Mountains northward along the Front Range should intensify as it impinges on the strengthening buoyancy plume over the central High Plains. For additional short-term information, see MCD 1262. ..Grams.. 06/14/2024 .PREV DISCUSSION... /ISSUED 1128 AM CDT Fri Jun 14 2024/ ...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. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0246 PM CDT Fri Jun 14 2024 Valid 142000Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF CO/KS/NE AND THE UPPER OH VALLEY TO NEW ENGLAND... ...SUMMARY... Scattered severe thunderstorms with large hail and wind gusts around 60-80 mph will be possible through this evening along the Front Range to the central Great Plains. Scattered strong to locally severe storms with sporadic damaging winds and isolated hail will also be possible across parts of the Northeast and Mid-Atlantic through about dusk. ...20Z Update... Convection from New England to the Upper OH Valley has largely struggled to greatly intensify beyond a marginally severe status as of yet. Still, where boundary-layer warming has been more pronounced from parts of the Upper OH Valley, DE Valley, and southern to eastern New England, a few clusters may yet produce strong to localized severe gust before convection diminishes after dusk. The central states severe threat appears on-track. Deepening convection from the Sangre de Cristo Mountains northward along the Front Range should intensify as it impinges on the strengthening buoyancy plume over the central High Plains. For additional short-term information, see MCD 1262. ..Grams.. 06/14/2024 .PREV DISCUSSION... /ISSUED 1128 AM CDT Fri Jun 14 2024/ ...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. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0246 PM CDT Fri Jun 14 2024 Valid 142000Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF CO/KS/NE AND THE UPPER OH VALLEY TO NEW ENGLAND... ...SUMMARY... Scattered severe thunderstorms with large hail and wind gusts around 60-80 mph will be possible through this evening along the Front Range to the central Great Plains. Scattered strong to locally severe storms with sporadic damaging winds and isolated hail will also be possible across parts of the Northeast and Mid-Atlantic through about dusk. ...20Z Update... Convection from New England to the Upper OH Valley has largely struggled to greatly intensify beyond a marginally severe status as of yet. Still, where boundary-layer warming has been more pronounced from parts of the Upper OH Valley, DE Valley, and southern to eastern New England, a few clusters may yet produce strong to localized severe gust before convection diminishes after dusk. The central states severe threat appears on-track. Deepening convection from the Sangre de Cristo Mountains northward along the Front Range should intensify as it impinges on the strengthening buoyancy plume over the central High Plains. For additional short-term information, see MCD 1262. ..Grams.. 06/14/2024 .PREV DISCUSSION... /ISSUED 1128 AM CDT Fri Jun 14 2024/ ...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. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0246 PM CDT Fri Jun 14 2024 Valid 142000Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF CO/KS/NE AND THE UPPER OH VALLEY TO NEW ENGLAND... ...SUMMARY... Scattered severe thunderstorms with large hail and wind gusts around 60-80 mph will be possible through this evening along the Front Range to the central Great Plains. Scattered strong to locally severe storms with sporadic damaging winds and isolated hail will also be possible across parts of the Northeast and Mid-Atlantic through about dusk. ...20Z Update... Convection from New England to the Upper OH Valley has largely struggled to greatly intensify beyond a marginally severe status as of yet. Still, where boundary-layer warming has been more pronounced from parts of the Upper OH Valley, DE Valley, and southern to eastern New England, a few clusters may yet produce strong to localized severe gust before convection diminishes after dusk. The central states severe threat appears on-track. Deepening convection from the Sangre de Cristo Mountains northward along the Front Range should intensify as it impinges on the strengthening buoyancy plume over the central High Plains. For additional short-term information, see MCD 1262. ..Grams.. 06/14/2024 .PREV DISCUSSION... /ISSUED 1128 AM CDT Fri Jun 14 2024/ ...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. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0246 PM CDT Fri Jun 14 2024 Valid 142000Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF CO/KS/NE AND THE UPPER OH VALLEY TO NEW ENGLAND... ...SUMMARY... Scattered severe thunderstorms with large hail and wind gusts around 60-80 mph will be possible through this evening along the Front Range to the central Great Plains. Scattered strong to locally severe storms with sporadic damaging winds and isolated hail will also be possible across parts of the Northeast and Mid-Atlantic through about dusk. ...20Z Update... Convection from New England to the Upper OH Valley has largely struggled to greatly intensify beyond a marginally severe status as of yet. Still, where boundary-layer warming has been more pronounced from parts of the Upper OH Valley, DE Valley, and southern to eastern New England, a few clusters may yet produce strong to localized severe gust before convection diminishes after dusk. The central states severe threat appears on-track. Deepening convection from the Sangre de Cristo Mountains northward along the Front Range should intensify as it impinges on the strengthening buoyancy plume over the central High Plains. For additional short-term information, see MCD 1262. ..Grams.. 06/14/2024 .PREV DISCUSSION... /ISSUED 1128 AM CDT Fri Jun 14 2024/ ...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. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0246 PM CDT Fri Jun 14 2024 Valid 142000Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF CO/KS/NE AND THE UPPER OH VALLEY TO NEW ENGLAND... ...SUMMARY... Scattered severe thunderstorms with large hail and wind gusts around 60-80 mph will be possible through this evening along the Front Range to the central Great Plains. Scattered strong to locally severe storms with sporadic damaging winds and isolated hail will also be possible across parts of the Northeast and Mid-Atlantic through about dusk. ...20Z Update... Convection from New England to the Upper OH Valley has largely struggled to greatly intensify beyond a marginally severe status as of yet. Still, where boundary-layer warming has been more pronounced from parts of the Upper OH Valley, DE Valley, and southern to eastern New England, a few clusters may yet produce strong to localized severe gust before convection diminishes after dusk. The central states severe threat appears on-track. Deepening convection from the Sangre de Cristo Mountains northward along the Front Range should intensify as it impinges on the strengthening buoyancy plume over the central High Plains. For additional short-term information, see MCD 1262. ..Grams.. 06/14/2024 .PREV DISCUSSION... /ISSUED 1128 AM CDT Fri Jun 14 2024/ ...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. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0246 PM CDT Fri Jun 14 2024 Valid 142000Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF CO/KS/NE AND THE UPPER OH VALLEY TO NEW ENGLAND... ...SUMMARY... Scattered severe thunderstorms with large hail and wind gusts around 60-80 mph will be possible through this evening along the Front Range to the central Great Plains. Scattered strong to locally severe storms with sporadic damaging winds and isolated hail will also be possible across parts of the Northeast and Mid-Atlantic through about dusk. ...20Z Update... Convection from New England to the Upper OH Valley has largely struggled to greatly intensify beyond a marginally severe status as of yet. Still, where boundary-layer warming has been more pronounced from parts of the Upper OH Valley, DE Valley, and southern to eastern New England, a few clusters may yet produce strong to localized severe gust before convection diminishes after dusk. The central states severe threat appears on-track. Deepening convection from the Sangre de Cristo Mountains northward along the Front Range should intensify as it impinges on the strengthening buoyancy plume over the central High Plains. For additional short-term information, see MCD 1262. ..Grams.. 06/14/2024 .PREV DISCUSSION... /ISSUED 1128 AM CDT Fri Jun 14 2024/ ...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. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0246 PM CDT Fri Jun 14 2024 Valid 142000Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF CO/KS/NE AND THE UPPER OH VALLEY TO NEW ENGLAND... ...SUMMARY... Scattered severe thunderstorms with large hail and wind gusts around 60-80 mph will be possible through this evening along the Front Range to the central Great Plains. Scattered strong to locally severe storms with sporadic damaging winds and isolated hail will also be possible across parts of the Northeast and Mid-Atlantic through about dusk. ...20Z Update... Convection from New England to the Upper OH Valley has largely struggled to greatly intensify beyond a marginally severe status as of yet. Still, where boundary-layer warming has been more pronounced from parts of the Upper OH Valley, DE Valley, and southern to eastern New England, a few clusters may yet produce strong to localized severe gust before convection diminishes after dusk. The central states severe threat appears on-track. Deepening convection from the Sangre de Cristo Mountains northward along the Front Range should intensify as it impinges on the strengthening buoyancy plume over the central High Plains. For additional short-term information, see MCD 1262. ..Grams.. 06/14/2024 .PREV DISCUSSION... /ISSUED 1128 AM CDT Fri Jun 14 2024/ ...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. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0246 PM CDT Fri Jun 14 2024 Valid 142000Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF CO/KS/NE AND THE UPPER OH VALLEY TO NEW ENGLAND... ...SUMMARY... Scattered severe thunderstorms with large hail and wind gusts around 60-80 mph will be possible through this evening along the Front Range to the central Great Plains. Scattered strong to locally severe storms with sporadic damaging winds and isolated hail will also be possible across parts of the Northeast and Mid-Atlantic through about dusk. ...20Z Update... Convection from New England to the Upper OH Valley has largely struggled to greatly intensify beyond a marginally severe status as of yet. Still, where boundary-layer warming has been more pronounced from parts of the Upper OH Valley, DE Valley, and southern to eastern New England, a few clusters may yet produce strong to localized severe gust before convection diminishes after dusk. The central states severe threat appears on-track. Deepening convection from the Sangre de Cristo Mountains northward along the Front Range should intensify as it impinges on the strengthening buoyancy plume over the central High Plains. For additional short-term information, see MCD 1262. ..Grams.. 06/14/2024 .PREV DISCUSSION... /ISSUED 1128 AM CDT Fri Jun 14 2024/ ...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. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0246 PM CDT Fri Jun 14 2024 Valid 142000Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF CO/KS/NE AND THE UPPER OH VALLEY TO NEW ENGLAND... ...SUMMARY... Scattered severe thunderstorms with large hail and wind gusts around 60-80 mph will be possible through this evening along the Front Range to the central Great Plains. Scattered strong to locally severe storms with sporadic damaging winds and isolated hail will also be possible across parts of the Northeast and Mid-Atlantic through about dusk. ...20Z Update... Convection from New England to the Upper OH Valley has largely struggled to greatly intensify beyond a marginally severe status as of yet. Still, where boundary-layer warming has been more pronounced from parts of the Upper OH Valley, DE Valley, and southern to eastern New England, a few clusters may yet produce strong to localized severe gust before convection diminishes after dusk. The central states severe threat appears on-track. Deepening convection from the Sangre de Cristo Mountains northward along the Front Range should intensify as it impinges on the strengthening buoyancy plume over the central High Plains. For additional short-term information, see MCD 1262. ..Grams.. 06/14/2024 .PREV DISCUSSION... /ISSUED 1128 AM CDT Fri Jun 14 2024/ ...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. Read more

MD 1259 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR NORTHEAST VT...NORTHERN/CENTRAL NH...ME
Mesoscale Discussion 1259 NWS Storm Prediction Center Norman OK 1218 PM CDT Fri Jun 14 2024 Areas affected...Northeast VT...Northern/Central NH...ME Concerning...Severe potential...Watch possible Valid 141718Z - 141915Z Probability of Watch Issuance...40 percent SUMMARY...Multiple rounds of thunderstorms are possible today from northeast Vermont and northern/central New Hampshire across much of Maine. Hail and damaging gusts are possible with the strongest storms, and trends will be monitored for possible watch issuance. DISCUSSION...Regional radar imagery shows thunderstorms are beginning to develop along and ahead of the cold front progressing southeastward into the region. Development thus far has occurred just along the leading edge of the better large-scale forcing for ascent, coincident with where modest low-level convergence within the vicinity of a weak pre-frontal trough is augmenting the more synoptic lift. The downstream air mass is only modestly buoyant, with current mesoanalysis estimating MLCAPE around 500 J/kg. Heating has been limited thus far, but cloud cover is beginning to thin, suggesting additional heating may occur in the region between the warm conveyor and the surface cold front. Additional heating would boost buoyancy, with stronger updrafts then more likely. Moderate vertical shear is in place, with regional VADs recently sampling 40 to 45 kt of 0-6 km bulk shear. Given the linear forcing and modest buoyancy, a linear multicellular mode will likely be the primary storm mode. However, vertical shear is strong enough to support supercell structures within any deeper, more sustained updrafts. Additionally, with the primary front still west of the region, multiple rounds of development along axes of low-level convergence are possible. Both hail and/damaging gusts are possible, but the hail threat will likely be confined to the more discrete storms. Overall severe coverage is uncertain, so convective trends will be monitored closely for potential watch issuance. ..Mosier/Gleason.. 06/14/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...CAR...GYX...BTV... LAT...LON 44956828 44306911 44056956 43787022 43637094 43617219 44157248 45017163 46247037 47056943 47006806 46106788 44956828 Read more

WW 0413 Status Updates
STATUS FOR WATCH 0413 HAS NOT BEEN ISSUED YET Read more

WW 0413 Status Updates
STATUS FOR WATCH 0413 HAS NOT BEEN ISSUED YET Read more

WW 0413 Status Updates
STATUS FOR WATCH 0413 HAS NOT BEEN ISSUED YET Read more

WW 0413 Status Updates
STATUS FOR WATCH 0413 HAS NOT BEEN ISSUED YET Read more

No watches are valid as of Fri Jun 14 17:58:01 UTC 2024.

MD 1258 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR WESTERN/CENTRAL PA
Mesoscale Discussion 1258 NWS Storm Prediction Center Norman OK 1117 AM CDT Fri Jun 14 2024 Areas affected...Western/Central PA Concerning...Severe potential...Watch possible Valid 141617Z - 141815Z Probability of Watch Issuance...40 percent SUMMARY...Some additional strengthening of the ongoing thunderstorms is possible over the next hour or two, with some new development probable as well. Isolated hail and/or damaging gusts are possible, and trends will be monitored for a possible watch. DISCUSSION...Ongoing thunderstorm cluster across western PA has shown a gradual strengthening trend over the past hour or so as it continues eastward at around 30 kt. Widespread cloud cover exists downstream across central PA, which has tempered heating thus far. Even so, some heating and moistening is likely ahead of this cluster over the next few hours, contributing to the potential for modest destabilization and some additional strengthening of the storms within this cluster. New development is also possible across the southern edge of this cluster, from southeast into south-central PA. Overall storm strength should be mitigated by the minimal buoyancy, but moderate westerly flow aloft could still support some organized storm structures capable of hail and/or damaging gusts. Uncertainty regarding severe coverage limits higher watch probabilities, but convective trends will be monitored closely. ..Mosier/Gleason.. 06/14/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...CTP...PBZ... LAT...LON 40768031 41737859 41897776 41787700 41207695 40017783 39747898 39938034 40768031 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Fri Jun 14 2024 Valid 151200Z - 161200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER THE MID-MO VALLEY AND NORTHERN GREAT PLAINS... ...SUMMARY... Scattered severe thunderstorms with damaging winds and large hail are possible from the late afternoon into the evening Saturday, across the Mid-Missouri Valley and in eastern Montana to central North Dakota. A couple tornadic storms may occur in eastern Nebraska to western Iowa, with isolated severe significant severe hail and wind possible in the northern Great Plains. ...Mid-MO Valley... A southern-stream shortwave trough currently centered near the Four Corners will progress northeast into parts of the central Great Plains to Upper Midwest by Saturday afternoon. This trough should contain multiple embedded impulses that are convectively enhanced from D1 convection over the High Plains. The greatest severe threat will likely emanate out of one such MCV as it progresses towards the Mid-MO Valley towards peak heating. While mid-level lapse rates will be weaker in vicinity of the MCV, ample low-level flow should be relatively strong ahead of the broader trough. A confined corridor of moderate to large buoyancy (MLCAPE of 2000-3000 J/kg), aided by greater low-level moisture along a residual frontal zone, should develop from the Ozark Plateau northwest into the Mid-MO Valley. Isolated to scattered thunderstorms are expected ahead of the MCV. At least a few of these should develop into supercells given the enhanced low-level SRH. Potential for a couple tornadic storms along with a risk for severe wind/hail should develop during the late afternoon through about dusk. This corridor will probably remain focused on the mesoscale as highlighted by a relatively confined level 2-SLGT. Strong low-level shear will exist with northeast extent in the Upper Midwest, but forecast soundings indicate convection will largely remain elevated, suggesting a more marginal severe hail/wind threat Saturday night. ...Northern Great Plains... A shortwave trough will move northeast across the Pacific Northwest into the southern SK vicinity by early Sunday. A pair of lee cyclones should develop near the Canadian Rockies and over the northern High Plains before tracking eastward into MB to the central Dakotas as a pronounced cold front accelerates eastward Saturday night. Multiple corridors of thunderstorms will likely develop during the late afternoon along the cold front and a lee trough, over southern to eastern MT and the western Dakotas. The degree of buoyancy with western extent into MT is somewhat uncertain where large-scale ascent will initially be greatest. But a plume of MLCAPE from 1500-2500 J/kg amid very steep mid-level lapse rates should develop from the central/western Dakotas into a part of eastern MT. Strengthening mid to upper-level flow with the approaching shortwave trough will yield potential for high-based supercells, conditionally favoring very large hail. 12Z HREF guidance signals convection largely forming west of the larger buoyancy plume and impinging on it during the evening. This suggests that a cluster to linear mode may occur relatively quickly with cold pools spreading east-northeast in the western to central Dakotas. Small-scale bowing structures may develop, locally enhancing severe wind intensity during the evening. Have expanded both level 1-2/MRGL-SLGT risks south and east to account for greater confidence in a mixed severe hail/wind threat occurring. ..Grams.. 06/14/2024 Read more