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No Mesoscale Discussions are in effect as of Sun Aug 25 20:01:03 UTC 2024.

WW 0646 Status Updates
STATUS FOR WATCH 0646 HAS NOT BEEN ISSUED YET Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0207 PM CDT Sun Aug 25 2024 Valid 271200Z - 281200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE GREAT LAKES... ...SUMMARY... Severe-weather potential is evident across the Great Lakes region on Tuesday. ...Great Lakes Vicinity... Only modest outlook changes have been made with the Day 3 update as overall pattern remains similar to prior thinking. An upper trough over the northern Plains will migrate east across the Great Lakes and southern Ontario. This will suppress the upper ridge over the Midwest while bringing a belt of enhanced westerly flow across the region. Convection will likely be ongoing across portions of WI/MI, though exact location of morning thunderstorms is a bit uncertain and will be driven by evolution of a possible MCS in the Day 2/Mon period. Nevertheless, a very moist boundary-layer is forecast, with surface dewpoints in the upper 60s to mid 70s F ahead of southeastward-advancing cold front. Strong to extreme instability is forecast, though some midlevel inhibition may persist across portions of the region. Nevertheless, this overall pattern continues to point toward severe thunderstorm potential, mainly in the form of severe/damaging gusts and large hail across the Great Lakes vicinity Tuesday into Tuesday evening. ...NE/IA vicinity... The western extent of the surface front will sag southward across the area. Strong differential heating along the boundary is forecast. A very moist boundary-layer will support strong instability, but warm midlevels leading to capping may preclude thunderstorm development. The Marginal risk (level 1 of 2) has been extended southwest along the forecast frontal zone for a conditional risk of severe storms during the afternoon into early evening as strong gusts and hail could occur if storms develop. ..Leitman.. 08/25/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0207 PM CDT Sun Aug 25 2024 Valid 271200Z - 281200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE GREAT LAKES... ...SUMMARY... Severe-weather potential is evident across the Great Lakes region on Tuesday. ...Great Lakes Vicinity... Only modest outlook changes have been made with the Day 3 update as overall pattern remains similar to prior thinking. An upper trough over the northern Plains will migrate east across the Great Lakes and southern Ontario. This will suppress the upper ridge over the Midwest while bringing a belt of enhanced westerly flow across the region. Convection will likely be ongoing across portions of WI/MI, though exact location of morning thunderstorms is a bit uncertain and will be driven by evolution of a possible MCS in the Day 2/Mon period. Nevertheless, a very moist boundary-layer is forecast, with surface dewpoints in the upper 60s to mid 70s F ahead of southeastward-advancing cold front. Strong to extreme instability is forecast, though some midlevel inhibition may persist across portions of the region. Nevertheless, this overall pattern continues to point toward severe thunderstorm potential, mainly in the form of severe/damaging gusts and large hail across the Great Lakes vicinity Tuesday into Tuesday evening. ...NE/IA vicinity... The western extent of the surface front will sag southward across the area. Strong differential heating along the boundary is forecast. A very moist boundary-layer will support strong instability, but warm midlevels leading to capping may preclude thunderstorm development. The Marginal risk (level 1 of 2) has been extended southwest along the forecast frontal zone for a conditional risk of severe storms during the afternoon into early evening as strong gusts and hail could occur if storms develop. ..Leitman.. 08/25/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0207 PM CDT Sun Aug 25 2024 Valid 271200Z - 281200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE GREAT LAKES... ...SUMMARY... Severe-weather potential is evident across the Great Lakes region on Tuesday. ...Great Lakes Vicinity... Only modest outlook changes have been made with the Day 3 update as overall pattern remains similar to prior thinking. An upper trough over the northern Plains will migrate east across the Great Lakes and southern Ontario. This will suppress the upper ridge over the Midwest while bringing a belt of enhanced westerly flow across the region. Convection will likely be ongoing across portions of WI/MI, though exact location of morning thunderstorms is a bit uncertain and will be driven by evolution of a possible MCS in the Day 2/Mon period. Nevertheless, a very moist boundary-layer is forecast, with surface dewpoints in the upper 60s to mid 70s F ahead of southeastward-advancing cold front. Strong to extreme instability is forecast, though some midlevel inhibition may persist across portions of the region. Nevertheless, this overall pattern continues to point toward severe thunderstorm potential, mainly in the form of severe/damaging gusts and large hail across the Great Lakes vicinity Tuesday into Tuesday evening. ...NE/IA vicinity... The western extent of the surface front will sag southward across the area. Strong differential heating along the boundary is forecast. A very moist boundary-layer will support strong instability, but warm midlevels leading to capping may preclude thunderstorm development. The Marginal risk (level 1 of 2) has been extended southwest along the forecast frontal zone for a conditional risk of severe storms during the afternoon into early evening as strong gusts and hail could occur if storms develop. ..Leitman.. 08/25/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0207 PM CDT Sun Aug 25 2024 Valid 271200Z - 281200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE GREAT LAKES... ...SUMMARY... Severe-weather potential is evident across the Great Lakes region on Tuesday. ...Great Lakes Vicinity... Only modest outlook changes have been made with the Day 3 update as overall pattern remains similar to prior thinking. An upper trough over the northern Plains will migrate east across the Great Lakes and southern Ontario. This will suppress the upper ridge over the Midwest while bringing a belt of enhanced westerly flow across the region. Convection will likely be ongoing across portions of WI/MI, though exact location of morning thunderstorms is a bit uncertain and will be driven by evolution of a possible MCS in the Day 2/Mon period. Nevertheless, a very moist boundary-layer is forecast, with surface dewpoints in the upper 60s to mid 70s F ahead of southeastward-advancing cold front. Strong to extreme instability is forecast, though some midlevel inhibition may persist across portions of the region. Nevertheless, this overall pattern continues to point toward severe thunderstorm potential, mainly in the form of severe/damaging gusts and large hail across the Great Lakes vicinity Tuesday into Tuesday evening. ...NE/IA vicinity... The western extent of the surface front will sag southward across the area. Strong differential heating along the boundary is forecast. A very moist boundary-layer will support strong instability, but warm midlevels leading to capping may preclude thunderstorm development. The Marginal risk (level 1 of 2) has been extended southwest along the forecast frontal zone for a conditional risk of severe storms during the afternoon into early evening as strong gusts and hail could occur if storms develop. ..Leitman.. 08/25/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0207 PM CDT Sun Aug 25 2024 Valid 271200Z - 281200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE GREAT LAKES... ...SUMMARY... Severe-weather potential is evident across the Great Lakes region on Tuesday. ...Great Lakes Vicinity... Only modest outlook changes have been made with the Day 3 update as overall pattern remains similar to prior thinking. An upper trough over the northern Plains will migrate east across the Great Lakes and southern Ontario. This will suppress the upper ridge over the Midwest while bringing a belt of enhanced westerly flow across the region. Convection will likely be ongoing across portions of WI/MI, though exact location of morning thunderstorms is a bit uncertain and will be driven by evolution of a possible MCS in the Day 2/Mon period. Nevertheless, a very moist boundary-layer is forecast, with surface dewpoints in the upper 60s to mid 70s F ahead of southeastward-advancing cold front. Strong to extreme instability is forecast, though some midlevel inhibition may persist across portions of the region. Nevertheless, this overall pattern continues to point toward severe thunderstorm potential, mainly in the form of severe/damaging gusts and large hail across the Great Lakes vicinity Tuesday into Tuesday evening. ...NE/IA vicinity... The western extent of the surface front will sag southward across the area. Strong differential heating along the boundary is forecast. A very moist boundary-layer will support strong instability, but warm midlevels leading to capping may preclude thunderstorm development. The Marginal risk (level 1 of 2) has been extended southwest along the forecast frontal zone for a conditional risk of severe storms during the afternoon into early evening as strong gusts and hail could occur if storms develop. ..Leitman.. 08/25/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0207 PM CDT Sun Aug 25 2024 Valid 271200Z - 281200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE GREAT LAKES... ...SUMMARY... Severe-weather potential is evident across the Great Lakes region on Tuesday. ...Great Lakes Vicinity... Only modest outlook changes have been made with the Day 3 update as overall pattern remains similar to prior thinking. An upper trough over the northern Plains will migrate east across the Great Lakes and southern Ontario. This will suppress the upper ridge over the Midwest while bringing a belt of enhanced westerly flow across the region. Convection will likely be ongoing across portions of WI/MI, though exact location of morning thunderstorms is a bit uncertain and will be driven by evolution of a possible MCS in the Day 2/Mon period. Nevertheless, a very moist boundary-layer is forecast, with surface dewpoints in the upper 60s to mid 70s F ahead of southeastward-advancing cold front. Strong to extreme instability is forecast, though some midlevel inhibition may persist across portions of the region. Nevertheless, this overall pattern continues to point toward severe thunderstorm potential, mainly in the form of severe/damaging gusts and large hail across the Great Lakes vicinity Tuesday into Tuesday evening. ...NE/IA vicinity... The western extent of the surface front will sag southward across the area. Strong differential heating along the boundary is forecast. A very moist boundary-layer will support strong instability, but warm midlevels leading to capping may preclude thunderstorm development. The Marginal risk (level 1 of 2) has been extended southwest along the forecast frontal zone for a conditional risk of severe storms during the afternoon into early evening as strong gusts and hail could occur if storms develop. ..Leitman.. 08/25/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0207 PM CDT Sun Aug 25 2024 Valid 271200Z - 281200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE GREAT LAKES... ...SUMMARY... Severe-weather potential is evident across the Great Lakes region on Tuesday. ...Great Lakes Vicinity... Only modest outlook changes have been made with the Day 3 update as overall pattern remains similar to prior thinking. An upper trough over the northern Plains will migrate east across the Great Lakes and southern Ontario. This will suppress the upper ridge over the Midwest while bringing a belt of enhanced westerly flow across the region. Convection will likely be ongoing across portions of WI/MI, though exact location of morning thunderstorms is a bit uncertain and will be driven by evolution of a possible MCS in the Day 2/Mon period. Nevertheless, a very moist boundary-layer is forecast, with surface dewpoints in the upper 60s to mid 70s F ahead of southeastward-advancing cold front. Strong to extreme instability is forecast, though some midlevel inhibition may persist across portions of the region. Nevertheless, this overall pattern continues to point toward severe thunderstorm potential, mainly in the form of severe/damaging gusts and large hail across the Great Lakes vicinity Tuesday into Tuesday evening. ...NE/IA vicinity... The western extent of the surface front will sag southward across the area. Strong differential heating along the boundary is forecast. A very moist boundary-layer will support strong instability, but warm midlevels leading to capping may preclude thunderstorm development. The Marginal risk (level 1 of 2) has been extended southwest along the forecast frontal zone for a conditional risk of severe storms during the afternoon into early evening as strong gusts and hail could occur if storms develop. ..Leitman.. 08/25/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0207 PM CDT Sun Aug 25 2024 Valid 271200Z - 281200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE GREAT LAKES... ...SUMMARY... Severe-weather potential is evident across the Great Lakes region on Tuesday. ...Great Lakes Vicinity... Only modest outlook changes have been made with the Day 3 update as overall pattern remains similar to prior thinking. An upper trough over the northern Plains will migrate east across the Great Lakes and southern Ontario. This will suppress the upper ridge over the Midwest while bringing a belt of enhanced westerly flow across the region. Convection will likely be ongoing across portions of WI/MI, though exact location of morning thunderstorms is a bit uncertain and will be driven by evolution of a possible MCS in the Day 2/Mon period. Nevertheless, a very moist boundary-layer is forecast, with surface dewpoints in the upper 60s to mid 70s F ahead of southeastward-advancing cold front. Strong to extreme instability is forecast, though some midlevel inhibition may persist across portions of the region. Nevertheless, this overall pattern continues to point toward severe thunderstorm potential, mainly in the form of severe/damaging gusts and large hail across the Great Lakes vicinity Tuesday into Tuesday evening. ...NE/IA vicinity... The western extent of the surface front will sag southward across the area. Strong differential heating along the boundary is forecast. A very moist boundary-layer will support strong instability, but warm midlevels leading to capping may preclude thunderstorm development. The Marginal risk (level 1 of 2) has been extended southwest along the forecast frontal zone for a conditional risk of severe storms during the afternoon into early evening as strong gusts and hail could occur if storms develop. ..Leitman.. 08/25/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0207 PM CDT Sun Aug 25 2024 Valid 271200Z - 281200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE GREAT LAKES... ...SUMMARY... Severe-weather potential is evident across the Great Lakes region on Tuesday. ...Great Lakes Vicinity... Only modest outlook changes have been made with the Day 3 update as overall pattern remains similar to prior thinking. An upper trough over the northern Plains will migrate east across the Great Lakes and southern Ontario. This will suppress the upper ridge over the Midwest while bringing a belt of enhanced westerly flow across the region. Convection will likely be ongoing across portions of WI/MI, though exact location of morning thunderstorms is a bit uncertain and will be driven by evolution of a possible MCS in the Day 2/Mon period. Nevertheless, a very moist boundary-layer is forecast, with surface dewpoints in the upper 60s to mid 70s F ahead of southeastward-advancing cold front. Strong to extreme instability is forecast, though some midlevel inhibition may persist across portions of the region. Nevertheless, this overall pattern continues to point toward severe thunderstorm potential, mainly in the form of severe/damaging gusts and large hail across the Great Lakes vicinity Tuesday into Tuesday evening. ...NE/IA vicinity... The western extent of the surface front will sag southward across the area. Strong differential heating along the boundary is forecast. A very moist boundary-layer will support strong instability, but warm midlevels leading to capping may preclude thunderstorm development. The Marginal risk (level 1 of 2) has been extended southwest along the forecast frontal zone for a conditional risk of severe storms during the afternoon into early evening as strong gusts and hail could occur if storms develop. ..Leitman.. 08/25/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0207 PM CDT Sun Aug 25 2024 Valid 271200Z - 281200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE GREAT LAKES... ...SUMMARY... Severe-weather potential is evident across the Great Lakes region on Tuesday. ...Great Lakes Vicinity... Only modest outlook changes have been made with the Day 3 update as overall pattern remains similar to prior thinking. An upper trough over the northern Plains will migrate east across the Great Lakes and southern Ontario. This will suppress the upper ridge over the Midwest while bringing a belt of enhanced westerly flow across the region. Convection will likely be ongoing across portions of WI/MI, though exact location of morning thunderstorms is a bit uncertain and will be driven by evolution of a possible MCS in the Day 2/Mon period. Nevertheless, a very moist boundary-layer is forecast, with surface dewpoints in the upper 60s to mid 70s F ahead of southeastward-advancing cold front. Strong to extreme instability is forecast, though some midlevel inhibition may persist across portions of the region. Nevertheless, this overall pattern continues to point toward severe thunderstorm potential, mainly in the form of severe/damaging gusts and large hail across the Great Lakes vicinity Tuesday into Tuesday evening. ...NE/IA vicinity... The western extent of the surface front will sag southward across the area. Strong differential heating along the boundary is forecast. A very moist boundary-layer will support strong instability, but warm midlevels leading to capping may preclude thunderstorm development. The Marginal risk (level 1 of 2) has been extended southwest along the forecast frontal zone for a conditional risk of severe storms during the afternoon into early evening as strong gusts and hail could occur if storms develop. ..Leitman.. 08/25/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0207 PM CDT Sun Aug 25 2024 Valid 271200Z - 281200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE GREAT LAKES... ...SUMMARY... Severe-weather potential is evident across the Great Lakes region on Tuesday. ...Great Lakes Vicinity... Only modest outlook changes have been made with the Day 3 update as overall pattern remains similar to prior thinking. An upper trough over the northern Plains will migrate east across the Great Lakes and southern Ontario. This will suppress the upper ridge over the Midwest while bringing a belt of enhanced westerly flow across the region. Convection will likely be ongoing across portions of WI/MI, though exact location of morning thunderstorms is a bit uncertain and will be driven by evolution of a possible MCS in the Day 2/Mon period. Nevertheless, a very moist boundary-layer is forecast, with surface dewpoints in the upper 60s to mid 70s F ahead of southeastward-advancing cold front. Strong to extreme instability is forecast, though some midlevel inhibition may persist across portions of the region. Nevertheless, this overall pattern continues to point toward severe thunderstorm potential, mainly in the form of severe/damaging gusts and large hail across the Great Lakes vicinity Tuesday into Tuesday evening. ...NE/IA vicinity... The western extent of the surface front will sag southward across the area. Strong differential heating along the boundary is forecast. A very moist boundary-layer will support strong instability, but warm midlevels leading to capping may preclude thunderstorm development. The Marginal risk (level 1 of 2) has been extended southwest along the forecast frontal zone for a conditional risk of severe storms during the afternoon into early evening as strong gusts and hail could occur if storms develop. ..Leitman.. 08/25/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0207 PM CDT Sun Aug 25 2024 Valid 271200Z - 281200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE GREAT LAKES... ...SUMMARY... Severe-weather potential is evident across the Great Lakes region on Tuesday. ...Great Lakes Vicinity... Only modest outlook changes have been made with the Day 3 update as overall pattern remains similar to prior thinking. An upper trough over the northern Plains will migrate east across the Great Lakes and southern Ontario. This will suppress the upper ridge over the Midwest while bringing a belt of enhanced westerly flow across the region. Convection will likely be ongoing across portions of WI/MI, though exact location of morning thunderstorms is a bit uncertain and will be driven by evolution of a possible MCS in the Day 2/Mon period. Nevertheless, a very moist boundary-layer is forecast, with surface dewpoints in the upper 60s to mid 70s F ahead of southeastward-advancing cold front. Strong to extreme instability is forecast, though some midlevel inhibition may persist across portions of the region. Nevertheless, this overall pattern continues to point toward severe thunderstorm potential, mainly in the form of severe/damaging gusts and large hail across the Great Lakes vicinity Tuesday into Tuesday evening. ...NE/IA vicinity... The western extent of the surface front will sag southward across the area. Strong differential heating along the boundary is forecast. A very moist boundary-layer will support strong instability, but warm midlevels leading to capping may preclude thunderstorm development. The Marginal risk (level 1 of 2) has been extended southwest along the forecast frontal zone for a conditional risk of severe storms during the afternoon into early evening as strong gusts and hail could occur if storms develop. ..Leitman.. 08/25/2024 Read more

No watches are valid as of Sun Aug 25 19:10:02 UTC 2024.

MD 1987 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR PARTS OF EASTERN UTAH...ADJACENT NORTHWESTERN COLORADO AND SOUTHWESTERN WYOMING
Mesoscale Discussion 1987 NWS Storm Prediction Center Norman OK 1127 AM CDT Sun Aug 25 2024 Areas affected...parts of eastern Utah...adjacent northwestern Colorado and southwestern Wyoming Concerning...Severe potential...Watch possible Valid 251627Z - 251830Z Probability of Watch Issuance...40 percent SUMMARY...Intensifying renewed thunderstorm development is possible across much of eastern Utah by 1-2 PM MDT. Widely scattered stronger storms may pose a risk for severe hail and wind while spreading northeastward and eastward through late afternoon. While it is still not yet certain that a severe weather watch will be needed, trends are being monitored for this possibility. DISCUSSION...Downstream of a seasonably vigorous short wave trough slowly progressing east-northeastward through the Great Basin, a narrow band of large-scale ascent continues to gradually spread east of the Wasatch. This is in the wake of initial low-level warm advection driven convection now spreading spreading northeastward through the Colorado and adjacent Wyoming Rockies, with insolation across a relatively moist boundary layer over much of eastern Utah contributing to increasing destabilization. Through 18-20Z, models suggest that mixed-layer CAPE may increase to 500-1000 J/kg, coincident with further strengthening of south to southwesterly mid/upper wind fields (including 30-70+ kt in the 700-300 mb layer). As new thunderstorm development begins to initiate, it appears that this regime will become potentially conducive to evolution of isolated supercells. In addition to posing a risk for large hail, stronger storms may become capable of producing locally severe wind gusts, particularly as they spread across the more strongly heated and deeply mixed lower elevations through late afternoon. ..Kerr/Guyer.. 08/25/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...RIW...GJT...SLC... LAT...LON 40631059 41650798 40220842 38420926 37600986 37181085 37551144 39331088 40631059 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1225 PM CDT Sun Aug 25 2024 Valid 261200Z - 271200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF FAR NORTHERN NEBRASKA...EXTREME NORTHWEST IOWA...EASTERN SOUTH DAKOTA...SOUTHERN/CENTRAL MINNESOTA...AND FAR WESTERN WISCONSIN... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF SOUTHERN NEW ENGLAND... ...SUMMARY... Severe storms are expected to evolve within a zone extending from the northern/central High Plains eastward to Wisconsin Monday afternoon into the nighttime hours. Large to very large hail, and swaths of severe, potentially damaging, gusts are expected, especially across South Dakota into Minnesota. A few severe storms producing strong gusts and hail are also expected across southern New England. ...South Dakota into MN/WI and vicinity... An upper shortwave trough will develop east/northeast from the Intermountain West to the Dakotas on Monday. This will flatten the upper ridge over the Upper Midwest and a belt of enhanced southwesterly mid/upper flow (50-60 kt at 500 mb) will overspread the region. By late afternoon, 700 mb flow is expected to increase to around 40-50 kt. Vertical wind profiles, and effective shear magnitudes increasing to greater than 40 kt, will support supercell thunderstorms. At the surface, a cold front will extend from northern MN southwestward into western SD during the morning. The front will develop southeast through the day and into the evening, becoming positioned from western WI/IA to the NE/KS border by Tuesday morning. Ahead of the front, a very moist airmass (upper 60s to mid 70s F dewpoints) will be in place across portions of MN/WI/IA and eastern SD, while a dryslot will be oriented over NE nosing into far southeast SD/western IA. With increasing ascent through the day, and persistent low-level warm advection, MLCIN should gradually erode. MLCAPE values across warm/moist sector are forecast as high as 3000-5000 J/kg, decreasing with southwest extent into the drier airmass. Steep midlevel lapse rates will within the strong to extremely unstable airmass will support robust updrafts, and initial supercell thunderstorms are expected to develop along the cold front from SD into MN. Large to very large (isolated stones greater than 2 inches diameter) will be possible. While damaging gusts will also be possible with cellular activity, one or more bowing segments/MCSs are expected to develop into the evening hours as convection shifts northeast across eastern SD/MN and eventually WI. As this occurs, potential for severe/damaging wind swaths will increase and a few gusts greater than 65 kt/75 mph are possible. Tornado potential is a bit more uncertain, but would likely be locally increased near and east of the surface low where low-level flow will remain more southeasterly. This will enhance low-level SRH and frontal convergence and a few tornadoes are possible with either supercells or within mesovortex formation along bowing segments. ...Northern/Central High Plains... Within the drier boundary-layer across southeast MT/eastern WY southward into eastern CO/western KS/western NE, scattered thunderstorms are expected to develop as the main upper trough overspreads the area during the afternoon. High-based thunderstorms amid steep low-level lapse rates will pose a risk for strong/isolated severe outflow winds. Isolated large hail also is possible, mainly from eastern WY into western SD/NE. ...New England and portions of the Upper OH Valley/Mid-Atlantic... Modestly enhanced deep-layer northwesterly flow on the back side of an upper trough will overspread the region. Pockets of 60 F dewpoints and cool temperatures aloft will support modest destabilization during the afternoon and thunderstorm bands/clusters are expected. Locally strong gusts will be possible with the activity. Isolated large hail also may be possible, especially over southern New England where forecast hodographs show more favorable vertical shear and elongated/straight hodographs. ..Leitman.. 08/25/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1225 PM CDT Sun Aug 25 2024 Valid 261200Z - 271200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF FAR NORTHERN NEBRASKA...EXTREME NORTHWEST IOWA...EASTERN SOUTH DAKOTA...SOUTHERN/CENTRAL MINNESOTA...AND FAR WESTERN WISCONSIN... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF SOUTHERN NEW ENGLAND... ...SUMMARY... Severe storms are expected to evolve within a zone extending from the northern/central High Plains eastward to Wisconsin Monday afternoon into the nighttime hours. Large to very large hail, and swaths of severe, potentially damaging, gusts are expected, especially across South Dakota into Minnesota. A few severe storms producing strong gusts and hail are also expected across southern New England. ...South Dakota into MN/WI and vicinity... An upper shortwave trough will develop east/northeast from the Intermountain West to the Dakotas on Monday. This will flatten the upper ridge over the Upper Midwest and a belt of enhanced southwesterly mid/upper flow (50-60 kt at 500 mb) will overspread the region. By late afternoon, 700 mb flow is expected to increase to around 40-50 kt. Vertical wind profiles, and effective shear magnitudes increasing to greater than 40 kt, will support supercell thunderstorms. At the surface, a cold front will extend from northern MN southwestward into western SD during the morning. The front will develop southeast through the day and into the evening, becoming positioned from western WI/IA to the NE/KS border by Tuesday morning. Ahead of the front, a very moist airmass (upper 60s to mid 70s F dewpoints) will be in place across portions of MN/WI/IA and eastern SD, while a dryslot will be oriented over NE nosing into far southeast SD/western IA. With increasing ascent through the day, and persistent low-level warm advection, MLCIN should gradually erode. MLCAPE values across warm/moist sector are forecast as high as 3000-5000 J/kg, decreasing with southwest extent into the drier airmass. Steep midlevel lapse rates will within the strong to extremely unstable airmass will support robust updrafts, and initial supercell thunderstorms are expected to develop along the cold front from SD into MN. Large to very large (isolated stones greater than 2 inches diameter) will be possible. While damaging gusts will also be possible with cellular activity, one or more bowing segments/MCSs are expected to develop into the evening hours as convection shifts northeast across eastern SD/MN and eventually WI. As this occurs, potential for severe/damaging wind swaths will increase and a few gusts greater than 65 kt/75 mph are possible. Tornado potential is a bit more uncertain, but would likely be locally increased near and east of the surface low where low-level flow will remain more southeasterly. This will enhance low-level SRH and frontal convergence and a few tornadoes are possible with either supercells or within mesovortex formation along bowing segments. ...Northern/Central High Plains... Within the drier boundary-layer across southeast MT/eastern WY southward into eastern CO/western KS/western NE, scattered thunderstorms are expected to develop as the main upper trough overspreads the area during the afternoon. High-based thunderstorms amid steep low-level lapse rates will pose a risk for strong/isolated severe outflow winds. Isolated large hail also is possible, mainly from eastern WY into western SD/NE. ...New England and portions of the Upper OH Valley/Mid-Atlantic... Modestly enhanced deep-layer northwesterly flow on the back side of an upper trough will overspread the region. Pockets of 60 F dewpoints and cool temperatures aloft will support modest destabilization during the afternoon and thunderstorm bands/clusters are expected. Locally strong gusts will be possible with the activity. Isolated large hail also may be possible, especially over southern New England where forecast hodographs show more favorable vertical shear and elongated/straight hodographs. ..Leitman.. 08/25/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1225 PM CDT Sun Aug 25 2024 Valid 261200Z - 271200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF FAR NORTHERN NEBRASKA...EXTREME NORTHWEST IOWA...EASTERN SOUTH DAKOTA...SOUTHERN/CENTRAL MINNESOTA...AND FAR WESTERN WISCONSIN... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF SOUTHERN NEW ENGLAND... ...SUMMARY... Severe storms are expected to evolve within a zone extending from the northern/central High Plains eastward to Wisconsin Monday afternoon into the nighttime hours. Large to very large hail, and swaths of severe, potentially damaging, gusts are expected, especially across South Dakota into Minnesota. A few severe storms producing strong gusts and hail are also expected across southern New England. ...South Dakota into MN/WI and vicinity... An upper shortwave trough will develop east/northeast from the Intermountain West to the Dakotas on Monday. This will flatten the upper ridge over the Upper Midwest and a belt of enhanced southwesterly mid/upper flow (50-60 kt at 500 mb) will overspread the region. By late afternoon, 700 mb flow is expected to increase to around 40-50 kt. Vertical wind profiles, and effective shear magnitudes increasing to greater than 40 kt, will support supercell thunderstorms. At the surface, a cold front will extend from northern MN southwestward into western SD during the morning. The front will develop southeast through the day and into the evening, becoming positioned from western WI/IA to the NE/KS border by Tuesday morning. Ahead of the front, a very moist airmass (upper 60s to mid 70s F dewpoints) will be in place across portions of MN/WI/IA and eastern SD, while a dryslot will be oriented over NE nosing into far southeast SD/western IA. With increasing ascent through the day, and persistent low-level warm advection, MLCIN should gradually erode. MLCAPE values across warm/moist sector are forecast as high as 3000-5000 J/kg, decreasing with southwest extent into the drier airmass. Steep midlevel lapse rates will within the strong to extremely unstable airmass will support robust updrafts, and initial supercell thunderstorms are expected to develop along the cold front from SD into MN. Large to very large (isolated stones greater than 2 inches diameter) will be possible. While damaging gusts will also be possible with cellular activity, one or more bowing segments/MCSs are expected to develop into the evening hours as convection shifts northeast across eastern SD/MN and eventually WI. As this occurs, potential for severe/damaging wind swaths will increase and a few gusts greater than 65 kt/75 mph are possible. Tornado potential is a bit more uncertain, but would likely be locally increased near and east of the surface low where low-level flow will remain more southeasterly. This will enhance low-level SRH and frontal convergence and a few tornadoes are possible with either supercells or within mesovortex formation along bowing segments. ...Northern/Central High Plains... Within the drier boundary-layer across southeast MT/eastern WY southward into eastern CO/western KS/western NE, scattered thunderstorms are expected to develop as the main upper trough overspreads the area during the afternoon. High-based thunderstorms amid steep low-level lapse rates will pose a risk for strong/isolated severe outflow winds. Isolated large hail also is possible, mainly from eastern WY into western SD/NE. ...New England and portions of the Upper OH Valley/Mid-Atlantic... Modestly enhanced deep-layer northwesterly flow on the back side of an upper trough will overspread the region. Pockets of 60 F dewpoints and cool temperatures aloft will support modest destabilization during the afternoon and thunderstorm bands/clusters are expected. Locally strong gusts will be possible with the activity. Isolated large hail also may be possible, especially over southern New England where forecast hodographs show more favorable vertical shear and elongated/straight hodographs. ..Leitman.. 08/25/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1225 PM CDT Sun Aug 25 2024 Valid 261200Z - 271200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF FAR NORTHERN NEBRASKA...EXTREME NORTHWEST IOWA...EASTERN SOUTH DAKOTA...SOUTHERN/CENTRAL MINNESOTA...AND FAR WESTERN WISCONSIN... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF SOUTHERN NEW ENGLAND... ...SUMMARY... Severe storms are expected to evolve within a zone extending from the northern/central High Plains eastward to Wisconsin Monday afternoon into the nighttime hours. Large to very large hail, and swaths of severe, potentially damaging, gusts are expected, especially across South Dakota into Minnesota. A few severe storms producing strong gusts and hail are also expected across southern New England. ...South Dakota into MN/WI and vicinity... An upper shortwave trough will develop east/northeast from the Intermountain West to the Dakotas on Monday. This will flatten the upper ridge over the Upper Midwest and a belt of enhanced southwesterly mid/upper flow (50-60 kt at 500 mb) will overspread the region. By late afternoon, 700 mb flow is expected to increase to around 40-50 kt. Vertical wind profiles, and effective shear magnitudes increasing to greater than 40 kt, will support supercell thunderstorms. At the surface, a cold front will extend from northern MN southwestward into western SD during the morning. The front will develop southeast through the day and into the evening, becoming positioned from western WI/IA to the NE/KS border by Tuesday morning. Ahead of the front, a very moist airmass (upper 60s to mid 70s F dewpoints) will be in place across portions of MN/WI/IA and eastern SD, while a dryslot will be oriented over NE nosing into far southeast SD/western IA. With increasing ascent through the day, and persistent low-level warm advection, MLCIN should gradually erode. MLCAPE values across warm/moist sector are forecast as high as 3000-5000 J/kg, decreasing with southwest extent into the drier airmass. Steep midlevel lapse rates will within the strong to extremely unstable airmass will support robust updrafts, and initial supercell thunderstorms are expected to develop along the cold front from SD into MN. Large to very large (isolated stones greater than 2 inches diameter) will be possible. While damaging gusts will also be possible with cellular activity, one or more bowing segments/MCSs are expected to develop into the evening hours as convection shifts northeast across eastern SD/MN and eventually WI. As this occurs, potential for severe/damaging wind swaths will increase and a few gusts greater than 65 kt/75 mph are possible. Tornado potential is a bit more uncertain, but would likely be locally increased near and east of the surface low where low-level flow will remain more southeasterly. This will enhance low-level SRH and frontal convergence and a few tornadoes are possible with either supercells or within mesovortex formation along bowing segments. ...Northern/Central High Plains... Within the drier boundary-layer across southeast MT/eastern WY southward into eastern CO/western KS/western NE, scattered thunderstorms are expected to develop as the main upper trough overspreads the area during the afternoon. High-based thunderstorms amid steep low-level lapse rates will pose a risk for strong/isolated severe outflow winds. Isolated large hail also is possible, mainly from eastern WY into western SD/NE. ...New England and portions of the Upper OH Valley/Mid-Atlantic... Modestly enhanced deep-layer northwesterly flow on the back side of an upper trough will overspread the region. Pockets of 60 F dewpoints and cool temperatures aloft will support modest destabilization during the afternoon and thunderstorm bands/clusters are expected. Locally strong gusts will be possible with the activity. Isolated large hail also may be possible, especially over southern New England where forecast hodographs show more favorable vertical shear and elongated/straight hodographs. ..Leitman.. 08/25/2024 Read more