Severe Storms

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0300 PM CDT Sun Jun 22 2025 Valid 222000Z - 231200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE MIDWEST TO PORTIONS OF THE CENTRAL AND SOUTHERN PLAINS.... ...SUMMARY... Isolated to scattered thunderstorms are expected today across the northern Plains and Upper Mississippi Valley, some of which could produce large hail, damaging wind gusts and tornadoes. Storms associated with severe gusts and hail may also develop across parts of the southern and central Plains, and Northeast. ...20z Update Central/Northern Plains... Current surface and satellite observations show strong heating occurring from far eastern WY, into the NE panhandle within a post-frontal upslope flow regime. As ascent from the primary trough across the northern Rockies moves overhead, storm initiation appears likely this afternoon. Weak destabilization, with moderate deep-layer shear suggests a few supercells are likely with hail and damaging winds the primary risk. A brief tornado is also possible with the stronger surface-based supercells given strong low-level veering. The MRGL and SLGT boundaries have been adjusted westward to better align with expected storm initiation along the terrain and stalled front. See MCD#1403 for additional short-term info. To the north across eastern SD/ND and MN, the severe risk continues largely as expected. Strong heating ahead of a surface low and warm front will support scattered storm development this afternoon and evening. Deep-layer shear will support supercells and clusters capable of all severe hazards. Storms will continue eastward this evening and overnight across northern MN with damaging gusts and hail likely. ...Northeast... In the wake of an earlier MCS, strong heating remains evident along a remnant outflow boundary from eastern PA into southwestern NY state. However, mid-level height rises and subsidence are evident in visible/WV imagery and will continue to suppress convective development over much of the region. An isolated storm or two remains possible along the boundary through late this afternoon, but more widespread convective coverage is unlikely. Should storms form, a strong/severe wind gusts will be possible, in addition to sporadic hail, given seasonably large buoyancy and steep mid-level lapse rates. With decreased confidence in storm development/coverage, have opted to remove the SLGT risk and continue with 5% wind/hail probabilities. ..Lyons.. 06/22/2025 .PREV DISCUSSION... /ISSUED 1136 AM CDT Sun Jun 22 2025/ ...Northern/Central Plains into the Upper Midwest... A warm front extends northeast from a surface low over northern SD across northern MN and east across the northern Great Lakes. This warm front should lift north through the day, while a cold front extends southwest of the surface low into northeast CO. Thunderstorms over eastern ND/northwest MN have produced near severe gusts as they continue to move northeast towards the international border. Redevelopment of thunderstorms is anticipated towards late afternoon or early evening across eastern ND/western MN southward into eastern SD as a weak mid-level perturbation lifts northeast across the area, contributing large-scale ascent and weakening the capping inversion. These storms will move east/northeast within a strongly unstable air mass and include a mix of supercell and cluster modes with a risk for large to very large hail initially, and transition into an increasing wind threat with time. Tornado potential appears to be greatest over northern MN, where low-level SRH will be maximized. The potential for elevated, post-frontal thunderstorm development across the NE Panhandle will exist later this afternoon/evening, with storms moving east and posing a risk initially for severe hail. The severe wind potential will increase with eastward extent as storms congeal and tap greater surface instability farther east. ...Central/Southern High Plains... Low-level moisture advection and related airmass destabilization coupled with low-level convergence along the lee trough is expected to result in thunderstorm development from eastern CO/western KS through eastern NM and into far west TX. Vertical shear will be modest, likely resulting in predominantly outflow-dominant storm structures and the potential for damaging wind gusts. Some isolated hail is also possible with the strongest/more persistent updrafts. ...Northeast... Overall storm intensity along the western flank of outflow from the long-lived MCS remains sub severe, and have narrowed the Marginal and Slight Risk areas to along and immediately southwest of the convective line. Substantial diurnal heating of a very moist air mass, and 30-40 kts of effective shear, may support some severe potential as storms move generally southward along the eastern periphery of the mid-level ridge. Isolated to widely scattered strong/severe wind gusts will be possible, in addition to isolated hail reports given seasonably steep mid-level lapse rates. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0300 PM CDT Sun Jun 22 2025 Valid 222000Z - 231200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE MIDWEST TO PORTIONS OF THE CENTRAL AND SOUTHERN PLAINS.... ...SUMMARY... Isolated to scattered thunderstorms are expected today across the northern Plains and Upper Mississippi Valley, some of which could produce large hail, damaging wind gusts and tornadoes. Storms associated with severe gusts and hail may also develop across parts of the southern and central Plains, and Northeast. ...20z Update Central/Northern Plains... Current surface and satellite observations show strong heating occurring from far eastern WY, into the NE panhandle within a post-frontal upslope flow regime. As ascent from the primary trough across the northern Rockies moves overhead, storm initiation appears likely this afternoon. Weak destabilization, with moderate deep-layer shear suggests a few supercells are likely with hail and damaging winds the primary risk. A brief tornado is also possible with the stronger surface-based supercells given strong low-level veering. The MRGL and SLGT boundaries have been adjusted westward to better align with expected storm initiation along the terrain and stalled front. See MCD#1403 for additional short-term info. To the north across eastern SD/ND and MN, the severe risk continues largely as expected. Strong heating ahead of a surface low and warm front will support scattered storm development this afternoon and evening. Deep-layer shear will support supercells and clusters capable of all severe hazards. Storms will continue eastward this evening and overnight across northern MN with damaging gusts and hail likely. ...Northeast... In the wake of an earlier MCS, strong heating remains evident along a remnant outflow boundary from eastern PA into southwestern NY state. However, mid-level height rises and subsidence are evident in visible/WV imagery and will continue to suppress convective development over much of the region. An isolated storm or two remains possible along the boundary through late this afternoon, but more widespread convective coverage is unlikely. Should storms form, a strong/severe wind gusts will be possible, in addition to sporadic hail, given seasonably large buoyancy and steep mid-level lapse rates. With decreased confidence in storm development/coverage, have opted to remove the SLGT risk and continue with 5% wind/hail probabilities. ..Lyons.. 06/22/2025 .PREV DISCUSSION... /ISSUED 1136 AM CDT Sun Jun 22 2025/ ...Northern/Central Plains into the Upper Midwest... A warm front extends northeast from a surface low over northern SD across northern MN and east across the northern Great Lakes. This warm front should lift north through the day, while a cold front extends southwest of the surface low into northeast CO. Thunderstorms over eastern ND/northwest MN have produced near severe gusts as they continue to move northeast towards the international border. Redevelopment of thunderstorms is anticipated towards late afternoon or early evening across eastern ND/western MN southward into eastern SD as a weak mid-level perturbation lifts northeast across the area, contributing large-scale ascent and weakening the capping inversion. These storms will move east/northeast within a strongly unstable air mass and include a mix of supercell and cluster modes with a risk for large to very large hail initially, and transition into an increasing wind threat with time. Tornado potential appears to be greatest over northern MN, where low-level SRH will be maximized. The potential for elevated, post-frontal thunderstorm development across the NE Panhandle will exist later this afternoon/evening, with storms moving east and posing a risk initially for severe hail. The severe wind potential will increase with eastward extent as storms congeal and tap greater surface instability farther east. ...Central/Southern High Plains... Low-level moisture advection and related airmass destabilization coupled with low-level convergence along the lee trough is expected to result in thunderstorm development from eastern CO/western KS through eastern NM and into far west TX. Vertical shear will be modest, likely resulting in predominantly outflow-dominant storm structures and the potential for damaging wind gusts. Some isolated hail is also possible with the strongest/more persistent updrafts. ...Northeast... Overall storm intensity along the western flank of outflow from the long-lived MCS remains sub severe, and have narrowed the Marginal and Slight Risk areas to along and immediately southwest of the convective line. Substantial diurnal heating of a very moist air mass, and 30-40 kts of effective shear, may support some severe potential as storms move generally southward along the eastern periphery of the mid-level ridge. Isolated to widely scattered strong/severe wind gusts will be possible, in addition to isolated hail reports given seasonably steep mid-level lapse rates. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0300 PM CDT Sun Jun 22 2025 Valid 222000Z - 231200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE MIDWEST TO PORTIONS OF THE CENTRAL AND SOUTHERN PLAINS.... ...SUMMARY... Isolated to scattered thunderstorms are expected today across the northern Plains and Upper Mississippi Valley, some of which could produce large hail, damaging wind gusts and tornadoes. Storms associated with severe gusts and hail may also develop across parts of the southern and central Plains, and Northeast. ...20z Update Central/Northern Plains... Current surface and satellite observations show strong heating occurring from far eastern WY, into the NE panhandle within a post-frontal upslope flow regime. As ascent from the primary trough across the northern Rockies moves overhead, storm initiation appears likely this afternoon. Weak destabilization, with moderate deep-layer shear suggests a few supercells are likely with hail and damaging winds the primary risk. A brief tornado is also possible with the stronger surface-based supercells given strong low-level veering. The MRGL and SLGT boundaries have been adjusted westward to better align with expected storm initiation along the terrain and stalled front. See MCD#1403 for additional short-term info. To the north across eastern SD/ND and MN, the severe risk continues largely as expected. Strong heating ahead of a surface low and warm front will support scattered storm development this afternoon and evening. Deep-layer shear will support supercells and clusters capable of all severe hazards. Storms will continue eastward this evening and overnight across northern MN with damaging gusts and hail likely. ...Northeast... In the wake of an earlier MCS, strong heating remains evident along a remnant outflow boundary from eastern PA into southwestern NY state. However, mid-level height rises and subsidence are evident in visible/WV imagery and will continue to suppress convective development over much of the region. An isolated storm or two remains possible along the boundary through late this afternoon, but more widespread convective coverage is unlikely. Should storms form, a strong/severe wind gusts will be possible, in addition to sporadic hail, given seasonably large buoyancy and steep mid-level lapse rates. With decreased confidence in storm development/coverage, have opted to remove the SLGT risk and continue with 5% wind/hail probabilities. ..Lyons.. 06/22/2025 .PREV DISCUSSION... /ISSUED 1136 AM CDT Sun Jun 22 2025/ ...Northern/Central Plains into the Upper Midwest... A warm front extends northeast from a surface low over northern SD across northern MN and east across the northern Great Lakes. This warm front should lift north through the day, while a cold front extends southwest of the surface low into northeast CO. Thunderstorms over eastern ND/northwest MN have produced near severe gusts as they continue to move northeast towards the international border. Redevelopment of thunderstorms is anticipated towards late afternoon or early evening across eastern ND/western MN southward into eastern SD as a weak mid-level perturbation lifts northeast across the area, contributing large-scale ascent and weakening the capping inversion. These storms will move east/northeast within a strongly unstable air mass and include a mix of supercell and cluster modes with a risk for large to very large hail initially, and transition into an increasing wind threat with time. Tornado potential appears to be greatest over northern MN, where low-level SRH will be maximized. The potential for elevated, post-frontal thunderstorm development across the NE Panhandle will exist later this afternoon/evening, with storms moving east and posing a risk initially for severe hail. The severe wind potential will increase with eastward extent as storms congeal and tap greater surface instability farther east. ...Central/Southern High Plains... Low-level moisture advection and related airmass destabilization coupled with low-level convergence along the lee trough is expected to result in thunderstorm development from eastern CO/western KS through eastern NM and into far west TX. Vertical shear will be modest, likely resulting in predominantly outflow-dominant storm structures and the potential for damaging wind gusts. Some isolated hail is also possible with the strongest/more persistent updrafts. ...Northeast... Overall storm intensity along the western flank of outflow from the long-lived MCS remains sub severe, and have narrowed the Marginal and Slight Risk areas to along and immediately southwest of the convective line. Substantial diurnal heating of a very moist air mass, and 30-40 kts of effective shear, may support some severe potential as storms move generally southward along the eastern periphery of the mid-level ridge. Isolated to widely scattered strong/severe wind gusts will be possible, in addition to isolated hail reports given seasonably steep mid-level lapse rates. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0300 PM CDT Sun Jun 22 2025 Valid 222000Z - 231200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE MIDWEST TO PORTIONS OF THE CENTRAL AND SOUTHERN PLAINS.... ...SUMMARY... Isolated to scattered thunderstorms are expected today across the northern Plains and Upper Mississippi Valley, some of which could produce large hail, damaging wind gusts and tornadoes. Storms associated with severe gusts and hail may also develop across parts of the southern and central Plains, and Northeast. ...20z Update Central/Northern Plains... Current surface and satellite observations show strong heating occurring from far eastern WY, into the NE panhandle within a post-frontal upslope flow regime. As ascent from the primary trough across the northern Rockies moves overhead, storm initiation appears likely this afternoon. Weak destabilization, with moderate deep-layer shear suggests a few supercells are likely with hail and damaging winds the primary risk. A brief tornado is also possible with the stronger surface-based supercells given strong low-level veering. The MRGL and SLGT boundaries have been adjusted westward to better align with expected storm initiation along the terrain and stalled front. See MCD#1403 for additional short-term info. To the north across eastern SD/ND and MN, the severe risk continues largely as expected. Strong heating ahead of a surface low and warm front will support scattered storm development this afternoon and evening. Deep-layer shear will support supercells and clusters capable of all severe hazards. Storms will continue eastward this evening and overnight across northern MN with damaging gusts and hail likely. ...Northeast... In the wake of an earlier MCS, strong heating remains evident along a remnant outflow boundary from eastern PA into southwestern NY state. However, mid-level height rises and subsidence are evident in visible/WV imagery and will continue to suppress convective development over much of the region. An isolated storm or two remains possible along the boundary through late this afternoon, but more widespread convective coverage is unlikely. Should storms form, a strong/severe wind gusts will be possible, in addition to sporadic hail, given seasonably large buoyancy and steep mid-level lapse rates. With decreased confidence in storm development/coverage, have opted to remove the SLGT risk and continue with 5% wind/hail probabilities. ..Lyons.. 06/22/2025 .PREV DISCUSSION... /ISSUED 1136 AM CDT Sun Jun 22 2025/ ...Northern/Central Plains into the Upper Midwest... A warm front extends northeast from a surface low over northern SD across northern MN and east across the northern Great Lakes. This warm front should lift north through the day, while a cold front extends southwest of the surface low into northeast CO. Thunderstorms over eastern ND/northwest MN have produced near severe gusts as they continue to move northeast towards the international border. Redevelopment of thunderstorms is anticipated towards late afternoon or early evening across eastern ND/western MN southward into eastern SD as a weak mid-level perturbation lifts northeast across the area, contributing large-scale ascent and weakening the capping inversion. These storms will move east/northeast within a strongly unstable air mass and include a mix of supercell and cluster modes with a risk for large to very large hail initially, and transition into an increasing wind threat with time. Tornado potential appears to be greatest over northern MN, where low-level SRH will be maximized. The potential for elevated, post-frontal thunderstorm development across the NE Panhandle will exist later this afternoon/evening, with storms moving east and posing a risk initially for severe hail. The severe wind potential will increase with eastward extent as storms congeal and tap greater surface instability farther east. ...Central/Southern High Plains... Low-level moisture advection and related airmass destabilization coupled with low-level convergence along the lee trough is expected to result in thunderstorm development from eastern CO/western KS through eastern NM and into far west TX. Vertical shear will be modest, likely resulting in predominantly outflow-dominant storm structures and the potential for damaging wind gusts. Some isolated hail is also possible with the strongest/more persistent updrafts. ...Northeast... Overall storm intensity along the western flank of outflow from the long-lived MCS remains sub severe, and have narrowed the Marginal and Slight Risk areas to along and immediately southwest of the convective line. Substantial diurnal heating of a very moist air mass, and 30-40 kts of effective shear, may support some severe potential as storms move generally southward along the eastern periphery of the mid-level ridge. Isolated to widely scattered strong/severe wind gusts will be possible, in addition to isolated hail reports given seasonably steep mid-level lapse rates. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0300 PM CDT Sun Jun 22 2025 Valid 222000Z - 231200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE MIDWEST TO PORTIONS OF THE CENTRAL AND SOUTHERN PLAINS.... ...SUMMARY... Isolated to scattered thunderstorms are expected today across the northern Plains and Upper Mississippi Valley, some of which could produce large hail, damaging wind gusts and tornadoes. Storms associated with severe gusts and hail may also develop across parts of the southern and central Plains, and Northeast. ...20z Update Central/Northern Plains... Current surface and satellite observations show strong heating occurring from far eastern WY, into the NE panhandle within a post-frontal upslope flow regime. As ascent from the primary trough across the northern Rockies moves overhead, storm initiation appears likely this afternoon. Weak destabilization, with moderate deep-layer shear suggests a few supercells are likely with hail and damaging winds the primary risk. A brief tornado is also possible with the stronger surface-based supercells given strong low-level veering. The MRGL and SLGT boundaries have been adjusted westward to better align with expected storm initiation along the terrain and stalled front. See MCD#1403 for additional short-term info. To the north across eastern SD/ND and MN, the severe risk continues largely as expected. Strong heating ahead of a surface low and warm front will support scattered storm development this afternoon and evening. Deep-layer shear will support supercells and clusters capable of all severe hazards. Storms will continue eastward this evening and overnight across northern MN with damaging gusts and hail likely. ...Northeast... In the wake of an earlier MCS, strong heating remains evident along a remnant outflow boundary from eastern PA into southwestern NY state. However, mid-level height rises and subsidence are evident in visible/WV imagery and will continue to suppress convective development over much of the region. An isolated storm or two remains possible along the boundary through late this afternoon, but more widespread convective coverage is unlikely. Should storms form, a strong/severe wind gusts will be possible, in addition to sporadic hail, given seasonably large buoyancy and steep mid-level lapse rates. With decreased confidence in storm development/coverage, have opted to remove the SLGT risk and continue with 5% wind/hail probabilities. ..Lyons.. 06/22/2025 .PREV DISCUSSION... /ISSUED 1136 AM CDT Sun Jun 22 2025/ ...Northern/Central Plains into the Upper Midwest... A warm front extends northeast from a surface low over northern SD across northern MN and east across the northern Great Lakes. This warm front should lift north through the day, while a cold front extends southwest of the surface low into northeast CO. Thunderstorms over eastern ND/northwest MN have produced near severe gusts as they continue to move northeast towards the international border. Redevelopment of thunderstorms is anticipated towards late afternoon or early evening across eastern ND/western MN southward into eastern SD as a weak mid-level perturbation lifts northeast across the area, contributing large-scale ascent and weakening the capping inversion. These storms will move east/northeast within a strongly unstable air mass and include a mix of supercell and cluster modes with a risk for large to very large hail initially, and transition into an increasing wind threat with time. Tornado potential appears to be greatest over northern MN, where low-level SRH will be maximized. The potential for elevated, post-frontal thunderstorm development across the NE Panhandle will exist later this afternoon/evening, with storms moving east and posing a risk initially for severe hail. The severe wind potential will increase with eastward extent as storms congeal and tap greater surface instability farther east. ...Central/Southern High Plains... Low-level moisture advection and related airmass destabilization coupled with low-level convergence along the lee trough is expected to result in thunderstorm development from eastern CO/western KS through eastern NM and into far west TX. Vertical shear will be modest, likely resulting in predominantly outflow-dominant storm structures and the potential for damaging wind gusts. Some isolated hail is also possible with the strongest/more persistent updrafts. ...Northeast... Overall storm intensity along the western flank of outflow from the long-lived MCS remains sub severe, and have narrowed the Marginal and Slight Risk areas to along and immediately southwest of the convective line. Substantial diurnal heating of a very moist air mass, and 30-40 kts of effective shear, may support some severe potential as storms move generally southward along the eastern periphery of the mid-level ridge. Isolated to widely scattered strong/severe wind gusts will be possible, in addition to isolated hail reports given seasonably steep mid-level lapse rates. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0300 PM CDT Sun Jun 22 2025 Valid 222000Z - 231200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE MIDWEST TO PORTIONS OF THE CENTRAL AND SOUTHERN PLAINS.... ...SUMMARY... Isolated to scattered thunderstorms are expected today across the northern Plains and Upper Mississippi Valley, some of which could produce large hail, damaging wind gusts and tornadoes. Storms associated with severe gusts and hail may also develop across parts of the southern and central Plains, and Northeast. ...20z Update Central/Northern Plains... Current surface and satellite observations show strong heating occurring from far eastern WY, into the NE panhandle within a post-frontal upslope flow regime. As ascent from the primary trough across the northern Rockies moves overhead, storm initiation appears likely this afternoon. Weak destabilization, with moderate deep-layer shear suggests a few supercells are likely with hail and damaging winds the primary risk. A brief tornado is also possible with the stronger surface-based supercells given strong low-level veering. The MRGL and SLGT boundaries have been adjusted westward to better align with expected storm initiation along the terrain and stalled front. See MCD#1403 for additional short-term info. To the north across eastern SD/ND and MN, the severe risk continues largely as expected. Strong heating ahead of a surface low and warm front will support scattered storm development this afternoon and evening. Deep-layer shear will support supercells and clusters capable of all severe hazards. Storms will continue eastward this evening and overnight across northern MN with damaging gusts and hail likely. ...Northeast... In the wake of an earlier MCS, strong heating remains evident along a remnant outflow boundary from eastern PA into southwestern NY state. However, mid-level height rises and subsidence are evident in visible/WV imagery and will continue to suppress convective development over much of the region. An isolated storm or two remains possible along the boundary through late this afternoon, but more widespread convective coverage is unlikely. Should storms form, a strong/severe wind gusts will be possible, in addition to sporadic hail, given seasonably large buoyancy and steep mid-level lapse rates. With decreased confidence in storm development/coverage, have opted to remove the SLGT risk and continue with 5% wind/hail probabilities. ..Lyons.. 06/22/2025 .PREV DISCUSSION... /ISSUED 1136 AM CDT Sun Jun 22 2025/ ...Northern/Central Plains into the Upper Midwest... A warm front extends northeast from a surface low over northern SD across northern MN and east across the northern Great Lakes. This warm front should lift north through the day, while a cold front extends southwest of the surface low into northeast CO. Thunderstorms over eastern ND/northwest MN have produced near severe gusts as they continue to move northeast towards the international border. Redevelopment of thunderstorms is anticipated towards late afternoon or early evening across eastern ND/western MN southward into eastern SD as a weak mid-level perturbation lifts northeast across the area, contributing large-scale ascent and weakening the capping inversion. These storms will move east/northeast within a strongly unstable air mass and include a mix of supercell and cluster modes with a risk for large to very large hail initially, and transition into an increasing wind threat with time. Tornado potential appears to be greatest over northern MN, where low-level SRH will be maximized. The potential for elevated, post-frontal thunderstorm development across the NE Panhandle will exist later this afternoon/evening, with storms moving east and posing a risk initially for severe hail. The severe wind potential will increase with eastward extent as storms congeal and tap greater surface instability farther east. ...Central/Southern High Plains... Low-level moisture advection and related airmass destabilization coupled with low-level convergence along the lee trough is expected to result in thunderstorm development from eastern CO/western KS through eastern NM and into far west TX. Vertical shear will be modest, likely resulting in predominantly outflow-dominant storm structures and the potential for damaging wind gusts. Some isolated hail is also possible with the strongest/more persistent updrafts. ...Northeast... Overall storm intensity along the western flank of outflow from the long-lived MCS remains sub severe, and have narrowed the Marginal and Slight Risk areas to along and immediately southwest of the convective line. Substantial diurnal heating of a very moist air mass, and 30-40 kts of effective shear, may support some severe potential as storms move generally southward along the eastern periphery of the mid-level ridge. Isolated to widely scattered strong/severe wind gusts will be possible, in addition to isolated hail reports given seasonably steep mid-level lapse rates. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0300 PM CDT Sun Jun 22 2025 Valid 222000Z - 231200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE MIDWEST TO PORTIONS OF THE CENTRAL AND SOUTHERN PLAINS.... ...SUMMARY... Isolated to scattered thunderstorms are expected today across the northern Plains and Upper Mississippi Valley, some of which could produce large hail, damaging wind gusts and tornadoes. Storms associated with severe gusts and hail may also develop across parts of the southern and central Plains, and Northeast. ...20z Update Central/Northern Plains... Current surface and satellite observations show strong heating occurring from far eastern WY, into the NE panhandle within a post-frontal upslope flow regime. As ascent from the primary trough across the northern Rockies moves overhead, storm initiation appears likely this afternoon. Weak destabilization, with moderate deep-layer shear suggests a few supercells are likely with hail and damaging winds the primary risk. A brief tornado is also possible with the stronger surface-based supercells given strong low-level veering. The MRGL and SLGT boundaries have been adjusted westward to better align with expected storm initiation along the terrain and stalled front. See MCD#1403 for additional short-term info. To the north across eastern SD/ND and MN, the severe risk continues largely as expected. Strong heating ahead of a surface low and warm front will support scattered storm development this afternoon and evening. Deep-layer shear will support supercells and clusters capable of all severe hazards. Storms will continue eastward this evening and overnight across northern MN with damaging gusts and hail likely. ...Northeast... In the wake of an earlier MCS, strong heating remains evident along a remnant outflow boundary from eastern PA into southwestern NY state. However, mid-level height rises and subsidence are evident in visible/WV imagery and will continue to suppress convective development over much of the region. An isolated storm or two remains possible along the boundary through late this afternoon, but more widespread convective coverage is unlikely. Should storms form, a strong/severe wind gusts will be possible, in addition to sporadic hail, given seasonably large buoyancy and steep mid-level lapse rates. With decreased confidence in storm development/coverage, have opted to remove the SLGT risk and continue with 5% wind/hail probabilities. ..Lyons.. 06/22/2025 .PREV DISCUSSION... /ISSUED 1136 AM CDT Sun Jun 22 2025/ ...Northern/Central Plains into the Upper Midwest... A warm front extends northeast from a surface low over northern SD across northern MN and east across the northern Great Lakes. This warm front should lift north through the day, while a cold front extends southwest of the surface low into northeast CO. Thunderstorms over eastern ND/northwest MN have produced near severe gusts as they continue to move northeast towards the international border. Redevelopment of thunderstorms is anticipated towards late afternoon or early evening across eastern ND/western MN southward into eastern SD as a weak mid-level perturbation lifts northeast across the area, contributing large-scale ascent and weakening the capping inversion. These storms will move east/northeast within a strongly unstable air mass and include a mix of supercell and cluster modes with a risk for large to very large hail initially, and transition into an increasing wind threat with time. Tornado potential appears to be greatest over northern MN, where low-level SRH will be maximized. The potential for elevated, post-frontal thunderstorm development across the NE Panhandle will exist later this afternoon/evening, with storms moving east and posing a risk initially for severe hail. The severe wind potential will increase with eastward extent as storms congeal and tap greater surface instability farther east. ...Central/Southern High Plains... Low-level moisture advection and related airmass destabilization coupled with low-level convergence along the lee trough is expected to result in thunderstorm development from eastern CO/western KS through eastern NM and into far west TX. Vertical shear will be modest, likely resulting in predominantly outflow-dominant storm structures and the potential for damaging wind gusts. Some isolated hail is also possible with the strongest/more persistent updrafts. ...Northeast... Overall storm intensity along the western flank of outflow from the long-lived MCS remains sub severe, and have narrowed the Marginal and Slight Risk areas to along and immediately southwest of the convective line. Substantial diurnal heating of a very moist air mass, and 30-40 kts of effective shear, may support some severe potential as storms move generally southward along the eastern periphery of the mid-level ridge. Isolated to widely scattered strong/severe wind gusts will be possible, in addition to isolated hail reports given seasonably steep mid-level lapse rates. Read more

WW 0451 Status Updates
STATUS FOR WATCH 0451 HAS NOT BEEN ISSUED YET Read more

WW 0451 Status Updates
STATUS FOR WATCH 0451 HAS NOT BEEN ISSUED YET Read more

WW 0451 Status Updates
STATUS FOR WATCH 0451 HAS NOT BEEN ISSUED YET Read more

No watches are valid as of Sun Jun 22 19:36:02 UTC 2025.

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0221 PM CDT Sun Jun 22 2025 Valid 241200Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER EASTERN WYOMING AND VICINITY... ...SUMMARY... Severe storms are possible Tuesday from eastern Wyoming into southwest South Dakota, the Nebraska Panhandle, and northeast Colorado. Isolated strong to severe storms will also be possible from parts of the central Plains and Midwest into the Northeast. ...Synopsis... The upper ridge over the East will flatten on Tuesday as a strong upper trough moves across Ontario and Quebec, with the strongest height falls occurring overnight. To the west, shortwave ridging will occur over the northern Plains during the day, as a weakening and low-amplitude wave moves from UT into WY through 00Z. This system will continue into the northern Plains overnight, providing cooling aloft. At the surface, high pressure will extend from the upper Great Lakes into the Southeast, with southerly winds persisting over the Plains. A boundary from Lower MI into NE will surge north as a warm front late in the day and overnight, with backed/easterly winds along this front allowing for near 60 F dewpoints as far west as eastern WY. Late in the day, a cold front associated with the Quebec upper trough will push south across NY, PA, and New England, providing a focus for storms as the antecedent air mass will be unstable. ...Northern to central High Plains... Morning thunderstorms may be ongoing from parts of NE and KS northeastward into Lower MI, but probably not severe at that time. As heating occurs, re-development is possible, both along the developing warm front or with any MCVs or residual outflow boundaries. The weak shear environment coupled with moderate instability will primarily yield sporadic clusters of strong to locally damaging wind gusts. Farther west into eastern WY and northeast CO, supercell potential will exist late in the day and during the evening, as moist easterly flow eventually becomes uncapped generally east of a Casper to Cheyenne to Denver line. Aided by steep lapse rates/heating over the higher terrain, and the approaching upper trough, widely scattered cells are anticipated, with large hail the most likely threat. A brief tornado cannot be ruled out. While capping will be an issue after dark, the lifting warm front may support additional storms into western SD/NE. ...Northeast Late Afternoon/Evening... Forecast soundings across the area depict relatively warm profiles aloft, though still unstable with 1500-2000 J/kg MUCAPE. Given this, widely scattered thunderstorms are expected from Lake Huron eastward into parts of New England late in the day. As these storms should be timed near peak heating, localized strong downbursts will be possible. ..Jewell.. 06/22/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0221 PM CDT Sun Jun 22 2025 Valid 241200Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER EASTERN WYOMING AND VICINITY... ...SUMMARY... Severe storms are possible Tuesday from eastern Wyoming into southwest South Dakota, the Nebraska Panhandle, and northeast Colorado. Isolated strong to severe storms will also be possible from parts of the central Plains and Midwest into the Northeast. ...Synopsis... The upper ridge over the East will flatten on Tuesday as a strong upper trough moves across Ontario and Quebec, with the strongest height falls occurring overnight. To the west, shortwave ridging will occur over the northern Plains during the day, as a weakening and low-amplitude wave moves from UT into WY through 00Z. This system will continue into the northern Plains overnight, providing cooling aloft. At the surface, high pressure will extend from the upper Great Lakes into the Southeast, with southerly winds persisting over the Plains. A boundary from Lower MI into NE will surge north as a warm front late in the day and overnight, with backed/easterly winds along this front allowing for near 60 F dewpoints as far west as eastern WY. Late in the day, a cold front associated with the Quebec upper trough will push south across NY, PA, and New England, providing a focus for storms as the antecedent air mass will be unstable. ...Northern to central High Plains... Morning thunderstorms may be ongoing from parts of NE and KS northeastward into Lower MI, but probably not severe at that time. As heating occurs, re-development is possible, both along the developing warm front or with any MCVs or residual outflow boundaries. The weak shear environment coupled with moderate instability will primarily yield sporadic clusters of strong to locally damaging wind gusts. Farther west into eastern WY and northeast CO, supercell potential will exist late in the day and during the evening, as moist easterly flow eventually becomes uncapped generally east of a Casper to Cheyenne to Denver line. Aided by steep lapse rates/heating over the higher terrain, and the approaching upper trough, widely scattered cells are anticipated, with large hail the most likely threat. A brief tornado cannot be ruled out. While capping will be an issue after dark, the lifting warm front may support additional storms into western SD/NE. ...Northeast Late Afternoon/Evening... Forecast soundings across the area depict relatively warm profiles aloft, though still unstable with 1500-2000 J/kg MUCAPE. Given this, widely scattered thunderstorms are expected from Lake Huron eastward into parts of New England late in the day. As these storms should be timed near peak heating, localized strong downbursts will be possible. ..Jewell.. 06/22/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0221 PM CDT Sun Jun 22 2025 Valid 241200Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER EASTERN WYOMING AND VICINITY... ...SUMMARY... Severe storms are possible Tuesday from eastern Wyoming into southwest South Dakota, the Nebraska Panhandle, and northeast Colorado. Isolated strong to severe storms will also be possible from parts of the central Plains and Midwest into the Northeast. ...Synopsis... The upper ridge over the East will flatten on Tuesday as a strong upper trough moves across Ontario and Quebec, with the strongest height falls occurring overnight. To the west, shortwave ridging will occur over the northern Plains during the day, as a weakening and low-amplitude wave moves from UT into WY through 00Z. This system will continue into the northern Plains overnight, providing cooling aloft. At the surface, high pressure will extend from the upper Great Lakes into the Southeast, with southerly winds persisting over the Plains. A boundary from Lower MI into NE will surge north as a warm front late in the day and overnight, with backed/easterly winds along this front allowing for near 60 F dewpoints as far west as eastern WY. Late in the day, a cold front associated with the Quebec upper trough will push south across NY, PA, and New England, providing a focus for storms as the antecedent air mass will be unstable. ...Northern to central High Plains... Morning thunderstorms may be ongoing from parts of NE and KS northeastward into Lower MI, but probably not severe at that time. As heating occurs, re-development is possible, both along the developing warm front or with any MCVs or residual outflow boundaries. The weak shear environment coupled with moderate instability will primarily yield sporadic clusters of strong to locally damaging wind gusts. Farther west into eastern WY and northeast CO, supercell potential will exist late in the day and during the evening, as moist easterly flow eventually becomes uncapped generally east of a Casper to Cheyenne to Denver line. Aided by steep lapse rates/heating over the higher terrain, and the approaching upper trough, widely scattered cells are anticipated, with large hail the most likely threat. A brief tornado cannot be ruled out. While capping will be an issue after dark, the lifting warm front may support additional storms into western SD/NE. ...Northeast Late Afternoon/Evening... Forecast soundings across the area depict relatively warm profiles aloft, though still unstable with 1500-2000 J/kg MUCAPE. Given this, widely scattered thunderstorms are expected from Lake Huron eastward into parts of New England late in the day. As these storms should be timed near peak heating, localized strong downbursts will be possible. ..Jewell.. 06/22/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0221 PM CDT Sun Jun 22 2025 Valid 241200Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER EASTERN WYOMING AND VICINITY... ...SUMMARY... Severe storms are possible Tuesday from eastern Wyoming into southwest South Dakota, the Nebraska Panhandle, and northeast Colorado. Isolated strong to severe storms will also be possible from parts of the central Plains and Midwest into the Northeast. ...Synopsis... The upper ridge over the East will flatten on Tuesday as a strong upper trough moves across Ontario and Quebec, with the strongest height falls occurring overnight. To the west, shortwave ridging will occur over the northern Plains during the day, as a weakening and low-amplitude wave moves from UT into WY through 00Z. This system will continue into the northern Plains overnight, providing cooling aloft. At the surface, high pressure will extend from the upper Great Lakes into the Southeast, with southerly winds persisting over the Plains. A boundary from Lower MI into NE will surge north as a warm front late in the day and overnight, with backed/easterly winds along this front allowing for near 60 F dewpoints as far west as eastern WY. Late in the day, a cold front associated with the Quebec upper trough will push south across NY, PA, and New England, providing a focus for storms as the antecedent air mass will be unstable. ...Northern to central High Plains... Morning thunderstorms may be ongoing from parts of NE and KS northeastward into Lower MI, but probably not severe at that time. As heating occurs, re-development is possible, both along the developing warm front or with any MCVs or residual outflow boundaries. The weak shear environment coupled with moderate instability will primarily yield sporadic clusters of strong to locally damaging wind gusts. Farther west into eastern WY and northeast CO, supercell potential will exist late in the day and during the evening, as moist easterly flow eventually becomes uncapped generally east of a Casper to Cheyenne to Denver line. Aided by steep lapse rates/heating over the higher terrain, and the approaching upper trough, widely scattered cells are anticipated, with large hail the most likely threat. A brief tornado cannot be ruled out. While capping will be an issue after dark, the lifting warm front may support additional storms into western SD/NE. ...Northeast Late Afternoon/Evening... Forecast soundings across the area depict relatively warm profiles aloft, though still unstable with 1500-2000 J/kg MUCAPE. Given this, widely scattered thunderstorms are expected from Lake Huron eastward into parts of New England late in the day. As these storms should be timed near peak heating, localized strong downbursts will be possible. ..Jewell.. 06/22/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0221 PM CDT Sun Jun 22 2025 Valid 241200Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER EASTERN WYOMING AND VICINITY... ...SUMMARY... Severe storms are possible Tuesday from eastern Wyoming into southwest South Dakota, the Nebraska Panhandle, and northeast Colorado. Isolated strong to severe storms will also be possible from parts of the central Plains and Midwest into the Northeast. ...Synopsis... The upper ridge over the East will flatten on Tuesday as a strong upper trough moves across Ontario and Quebec, with the strongest height falls occurring overnight. To the west, shortwave ridging will occur over the northern Plains during the day, as a weakening and low-amplitude wave moves from UT into WY through 00Z. This system will continue into the northern Plains overnight, providing cooling aloft. At the surface, high pressure will extend from the upper Great Lakes into the Southeast, with southerly winds persisting over the Plains. A boundary from Lower MI into NE will surge north as a warm front late in the day and overnight, with backed/easterly winds along this front allowing for near 60 F dewpoints as far west as eastern WY. Late in the day, a cold front associated with the Quebec upper trough will push south across NY, PA, and New England, providing a focus for storms as the antecedent air mass will be unstable. ...Northern to central High Plains... Morning thunderstorms may be ongoing from parts of NE and KS northeastward into Lower MI, but probably not severe at that time. As heating occurs, re-development is possible, both along the developing warm front or with any MCVs or residual outflow boundaries. The weak shear environment coupled with moderate instability will primarily yield sporadic clusters of strong to locally damaging wind gusts. Farther west into eastern WY and northeast CO, supercell potential will exist late in the day and during the evening, as moist easterly flow eventually becomes uncapped generally east of a Casper to Cheyenne to Denver line. Aided by steep lapse rates/heating over the higher terrain, and the approaching upper trough, widely scattered cells are anticipated, with large hail the most likely threat. A brief tornado cannot be ruled out. While capping will be an issue after dark, the lifting warm front may support additional storms into western SD/NE. ...Northeast Late Afternoon/Evening... Forecast soundings across the area depict relatively warm profiles aloft, though still unstable with 1500-2000 J/kg MUCAPE. Given this, widely scattered thunderstorms are expected from Lake Huron eastward into parts of New England late in the day. As these storms should be timed near peak heating, localized strong downbursts will be possible. ..Jewell.. 06/22/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0221 PM CDT Sun Jun 22 2025 Valid 241200Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER EASTERN WYOMING AND VICINITY... ...SUMMARY... Severe storms are possible Tuesday from eastern Wyoming into southwest South Dakota, the Nebraska Panhandle, and northeast Colorado. Isolated strong to severe storms will also be possible from parts of the central Plains and Midwest into the Northeast. ...Synopsis... The upper ridge over the East will flatten on Tuesday as a strong upper trough moves across Ontario and Quebec, with the strongest height falls occurring overnight. To the west, shortwave ridging will occur over the northern Plains during the day, as a weakening and low-amplitude wave moves from UT into WY through 00Z. This system will continue into the northern Plains overnight, providing cooling aloft. At the surface, high pressure will extend from the upper Great Lakes into the Southeast, with southerly winds persisting over the Plains. A boundary from Lower MI into NE will surge north as a warm front late in the day and overnight, with backed/easterly winds along this front allowing for near 60 F dewpoints as far west as eastern WY. Late in the day, a cold front associated with the Quebec upper trough will push south across NY, PA, and New England, providing a focus for storms as the antecedent air mass will be unstable. ...Northern to central High Plains... Morning thunderstorms may be ongoing from parts of NE and KS northeastward into Lower MI, but probably not severe at that time. As heating occurs, re-development is possible, both along the developing warm front or with any MCVs or residual outflow boundaries. The weak shear environment coupled with moderate instability will primarily yield sporadic clusters of strong to locally damaging wind gusts. Farther west into eastern WY and northeast CO, supercell potential will exist late in the day and during the evening, as moist easterly flow eventually becomes uncapped generally east of a Casper to Cheyenne to Denver line. Aided by steep lapse rates/heating over the higher terrain, and the approaching upper trough, widely scattered cells are anticipated, with large hail the most likely threat. A brief tornado cannot be ruled out. While capping will be an issue after dark, the lifting warm front may support additional storms into western SD/NE. ...Northeast Late Afternoon/Evening... Forecast soundings across the area depict relatively warm profiles aloft, though still unstable with 1500-2000 J/kg MUCAPE. Given this, widely scattered thunderstorms are expected from Lake Huron eastward into parts of New England late in the day. As these storms should be timed near peak heating, localized strong downbursts will be possible. ..Jewell.. 06/22/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0221 PM CDT Sun Jun 22 2025 Valid 241200Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER EASTERN WYOMING AND VICINITY... ...SUMMARY... Severe storms are possible Tuesday from eastern Wyoming into southwest South Dakota, the Nebraska Panhandle, and northeast Colorado. Isolated strong to severe storms will also be possible from parts of the central Plains and Midwest into the Northeast. ...Synopsis... The upper ridge over the East will flatten on Tuesday as a strong upper trough moves across Ontario and Quebec, with the strongest height falls occurring overnight. To the west, shortwave ridging will occur over the northern Plains during the day, as a weakening and low-amplitude wave moves from UT into WY through 00Z. This system will continue into the northern Plains overnight, providing cooling aloft. At the surface, high pressure will extend from the upper Great Lakes into the Southeast, with southerly winds persisting over the Plains. A boundary from Lower MI into NE will surge north as a warm front late in the day and overnight, with backed/easterly winds along this front allowing for near 60 F dewpoints as far west as eastern WY. Late in the day, a cold front associated with the Quebec upper trough will push south across NY, PA, and New England, providing a focus for storms as the antecedent air mass will be unstable. ...Northern to central High Plains... Morning thunderstorms may be ongoing from parts of NE and KS northeastward into Lower MI, but probably not severe at that time. As heating occurs, re-development is possible, both along the developing warm front or with any MCVs or residual outflow boundaries. The weak shear environment coupled with moderate instability will primarily yield sporadic clusters of strong to locally damaging wind gusts. Farther west into eastern WY and northeast CO, supercell potential will exist late in the day and during the evening, as moist easterly flow eventually becomes uncapped generally east of a Casper to Cheyenne to Denver line. Aided by steep lapse rates/heating over the higher terrain, and the approaching upper trough, widely scattered cells are anticipated, with large hail the most likely threat. A brief tornado cannot be ruled out. While capping will be an issue after dark, the lifting warm front may support additional storms into western SD/NE. ...Northeast Late Afternoon/Evening... Forecast soundings across the area depict relatively warm profiles aloft, though still unstable with 1500-2000 J/kg MUCAPE. Given this, widely scattered thunderstorms are expected from Lake Huron eastward into parts of New England late in the day. As these storms should be timed near peak heating, localized strong downbursts will be possible. ..Jewell.. 06/22/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0221 PM CDT Sun Jun 22 2025 Valid 241200Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER EASTERN WYOMING AND VICINITY... ...SUMMARY... Severe storms are possible Tuesday from eastern Wyoming into southwest South Dakota, the Nebraska Panhandle, and northeast Colorado. Isolated strong to severe storms will also be possible from parts of the central Plains and Midwest into the Northeast. ...Synopsis... The upper ridge over the East will flatten on Tuesday as a strong upper trough moves across Ontario and Quebec, with the strongest height falls occurring overnight. To the west, shortwave ridging will occur over the northern Plains during the day, as a weakening and low-amplitude wave moves from UT into WY through 00Z. This system will continue into the northern Plains overnight, providing cooling aloft. At the surface, high pressure will extend from the upper Great Lakes into the Southeast, with southerly winds persisting over the Plains. A boundary from Lower MI into NE will surge north as a warm front late in the day and overnight, with backed/easterly winds along this front allowing for near 60 F dewpoints as far west as eastern WY. Late in the day, a cold front associated with the Quebec upper trough will push south across NY, PA, and New England, providing a focus for storms as the antecedent air mass will be unstable. ...Northern to central High Plains... Morning thunderstorms may be ongoing from parts of NE and KS northeastward into Lower MI, but probably not severe at that time. As heating occurs, re-development is possible, both along the developing warm front or with any MCVs or residual outflow boundaries. The weak shear environment coupled with moderate instability will primarily yield sporadic clusters of strong to locally damaging wind gusts. Farther west into eastern WY and northeast CO, supercell potential will exist late in the day and during the evening, as moist easterly flow eventually becomes uncapped generally east of a Casper to Cheyenne to Denver line. Aided by steep lapse rates/heating over the higher terrain, and the approaching upper trough, widely scattered cells are anticipated, with large hail the most likely threat. A brief tornado cannot be ruled out. While capping will be an issue after dark, the lifting warm front may support additional storms into western SD/NE. ...Northeast Late Afternoon/Evening... Forecast soundings across the area depict relatively warm profiles aloft, though still unstable with 1500-2000 J/kg MUCAPE. Given this, widely scattered thunderstorms are expected from Lake Huron eastward into parts of New England late in the day. As these storms should be timed near peak heating, localized strong downbursts will be possible. ..Jewell.. 06/22/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0221 PM CDT Sun Jun 22 2025 Valid 241200Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER EASTERN WYOMING AND VICINITY... ...SUMMARY... Severe storms are possible Tuesday from eastern Wyoming into southwest South Dakota, the Nebraska Panhandle, and northeast Colorado. Isolated strong to severe storms will also be possible from parts of the central Plains and Midwest into the Northeast. ...Synopsis... The upper ridge over the East will flatten on Tuesday as a strong upper trough moves across Ontario and Quebec, with the strongest height falls occurring overnight. To the west, shortwave ridging will occur over the northern Plains during the day, as a weakening and low-amplitude wave moves from UT into WY through 00Z. This system will continue into the northern Plains overnight, providing cooling aloft. At the surface, high pressure will extend from the upper Great Lakes into the Southeast, with southerly winds persisting over the Plains. A boundary from Lower MI into NE will surge north as a warm front late in the day and overnight, with backed/easterly winds along this front allowing for near 60 F dewpoints as far west as eastern WY. Late in the day, a cold front associated with the Quebec upper trough will push south across NY, PA, and New England, providing a focus for storms as the antecedent air mass will be unstable. ...Northern to central High Plains... Morning thunderstorms may be ongoing from parts of NE and KS northeastward into Lower MI, but probably not severe at that time. As heating occurs, re-development is possible, both along the developing warm front or with any MCVs or residual outflow boundaries. The weak shear environment coupled with moderate instability will primarily yield sporadic clusters of strong to locally damaging wind gusts. Farther west into eastern WY and northeast CO, supercell potential will exist late in the day and during the evening, as moist easterly flow eventually becomes uncapped generally east of a Casper to Cheyenne to Denver line. Aided by steep lapse rates/heating over the higher terrain, and the approaching upper trough, widely scattered cells are anticipated, with large hail the most likely threat. A brief tornado cannot be ruled out. While capping will be an issue after dark, the lifting warm front may support additional storms into western SD/NE. ...Northeast Late Afternoon/Evening... Forecast soundings across the area depict relatively warm profiles aloft, though still unstable with 1500-2000 J/kg MUCAPE. Given this, widely scattered thunderstorms are expected from Lake Huron eastward into parts of New England late in the day. As these storms should be timed near peak heating, localized strong downbursts will be possible. ..Jewell.. 06/22/2025 Read more