SPC Jul 11, 2025 1730 UTC Day 2 Convective Outlook

1 month ago
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Fri Jul 11 2025 Valid 121200Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS CENTERED OVER EASTERN LOWER MICHIGAN AND OVER SOUTHWEST TEXAS... ...SUMMARY... Scattered damaging winds are possible across northeast Indiana, northwest Ohio, and eastern Michigan on Saturday. Large hail and damaging gusts are possible over much of southwest Texas into southeast New Mexico during the afternoon and evening. ...Synopsis... A shortwave trough will eject northeastward out of the upper MS Valley, while a separate weaker system drifts east across the central to southern Plains. Meanwhile, weak ridging will remain over the Southeast, with a stronger upper high over southern CA. At the surface, low pressure will move across Lower MI, with drying across the upper MS Valley as winds veer. A diffuse boundary will extend southwestward into parts of MO, KS, and OK, providing a focus for storms. ...Great Lakes Region... Strong heating will occur ahead of a cold front, with upper 60s F dewpoints over IN, OH, and much of Lower MI. Little cooling aloft is forecast with the glancing upper wave, but MLCAPE will likely exceed 2000 J/kg. Convergence within the surface trough will lead to scattered storms along the wind shift, with a few severe gusts and marginal hail possible. Low-level shear will be strongest over northern Lower MI, and an isolated supercell cannot be ruled out. Some uncertainty exist regarding overall storm coverage, as midlevel subsidence moves in late in the day. ...OH/Mid MS Valleys to the southern Plains... Ongoing storms with outflow may exist from parts of the South Plains into OK Saturday morning. Any associated boundaries may provide a focus for redevelopment during the afternoon, as 2000-3000 J/kg MUCAPE develops. Aside from that, moist easterly low-level flow through a deep layer will be favorable for thunderstorms across almost all of Southwest TX, including the Big Bend area. While shear will be weak, lightly veering winds with height along with steep lapse rates and strong instability should lead to a few robust, slow-moving storms with localized damaging hail and downburst potential. ..Jewell.. 07/11/2025 Read more

SPC Jul 11, 2025 1730 UTC Day 2 Convective Outlook

1 month ago
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Fri Jul 11 2025 Valid 121200Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS CENTERED OVER EASTERN LOWER MICHIGAN AND OVER SOUTHWEST TEXAS... ...SUMMARY... Scattered damaging winds are possible across northeast Indiana, northwest Ohio, and eastern Michigan on Saturday. Large hail and damaging gusts are possible over much of southwest Texas into southeast New Mexico during the afternoon and evening. ...Synopsis... A shortwave trough will eject northeastward out of the upper MS Valley, while a separate weaker system drifts east across the central to southern Plains. Meanwhile, weak ridging will remain over the Southeast, with a stronger upper high over southern CA. At the surface, low pressure will move across Lower MI, with drying across the upper MS Valley as winds veer. A diffuse boundary will extend southwestward into parts of MO, KS, and OK, providing a focus for storms. ...Great Lakes Region... Strong heating will occur ahead of a cold front, with upper 60s F dewpoints over IN, OH, and much of Lower MI. Little cooling aloft is forecast with the glancing upper wave, but MLCAPE will likely exceed 2000 J/kg. Convergence within the surface trough will lead to scattered storms along the wind shift, with a few severe gusts and marginal hail possible. Low-level shear will be strongest over northern Lower MI, and an isolated supercell cannot be ruled out. Some uncertainty exist regarding overall storm coverage, as midlevel subsidence moves in late in the day. ...OH/Mid MS Valleys to the southern Plains... Ongoing storms with outflow may exist from parts of the South Plains into OK Saturday morning. Any associated boundaries may provide a focus for redevelopment during the afternoon, as 2000-3000 J/kg MUCAPE develops. Aside from that, moist easterly low-level flow through a deep layer will be favorable for thunderstorms across almost all of Southwest TX, including the Big Bend area. While shear will be weak, lightly veering winds with height along with steep lapse rates and strong instability should lead to a few robust, slow-moving storms with localized damaging hail and downburst potential. ..Jewell.. 07/11/2025 Read more

SPC Jul 11, 2025 1630 UTC Day 1 Convective Outlook

1 month ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1131 AM CDT Fri Jul 11 2025 Valid 111630Z - 121200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM FAR NORTHEAST MO AND SOUTHEAST IA INTO NORTHWEST IL... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL AND SOUTHERN HIGH PLAINS... ...SUMMARY... Severe thunderstorms are expected this afternoon and evening across the Midwest to southern portions of the Great Lakes region, accompanied by a risk for damaging wind gusts, hail, as well as some tornado potential. Severe thunderstorms are also expected across the central/southern High Plains and Upper Midwest. ...Lower MO and Mid MS Valleys into Great Lakes... Recent surface analysis places a low over far southeast NE. Residual cloudiness and showers northeast of this low are helping to reinforce a warm-front-like baroclinic zone that extends from low eastward along the IA/MO border through central IL and IN. This boundary will likely sharpen throughout the day as the cloudiness and showers persist to its north and temperatures warm into 90s to its south. As a result, a reservoir of strong buoyancy is anticipated south of this boundary from southern IA into northern/central MO and western IL. Lift associated with the surface low, as well as its parent convectively augmented shortwave trough, will interact with this destabilized and buoyant airmass to support thunderstorm development by the early afternoon. Moderate vertical shear will be in place throughout the base of the shortwave, helping to organize some of these storms. However, the corridor of strongest shear is relatively narrow, with the broader environment characterized by weak mid-level flow and limited vertical shear. As such, a somewhat messy convection evolution appears probable. Initial development is expected over southern IA during the early afternoon. This activity will likely be elevated just north of the warm front. Additional warm sector development is also possible farther east across west-central/northwest IL. This initial development could be more cellular, with both hail and damaging gusts as primary risks. However, given the presence of a surface low as well as the warm front, some tornado risk is possible with these initially more cellular storms as well. Convective coverage is expected to increase with overall evolution towards a more linear mode anticipated with time. Damaging wind gusts should become the more predominant potential hazard as this occurs with the line moving east/southeastward this evening. Threat for brief embedded tornadoes exists within this evolving convective line as well. ...Central High Plains... The immediate post-frontal regime should be favorable for severe storm development this afternoon into evening across southeast WY and northeast CO into adjacent southwest NE/northwest KS. Some initial supercells capable of large hail can be expected, and one or more eastward-moving clusters may evolve by evening with severe-caliber winds also a possibility. ...Southern High Plains... Moderate low-level moisture (i.e. dewpoints in the upper 50 to low 60s) is currently in place across eastern NM, which will help offset some of the mixing anticipated as the airmass heats into the 90s this afternoon. Thunderstorm development is anticipated across the higher terrain of central/northern NM and the Raton Mesa, with these storms then progressing eastward/southeastward into the moderately moist, deeply mixed, and unstable airmass downstream across the southern High Plains. Numerous thunderstorms are expected, with the higher storm coverage likely facilitating cold pool amalgamation and the development of one or more forward-propagating convective clusters. Strong wind gusts would be possible within these clusters, with severe coverage expected to be high enough to merit introducing 15% wind probabilities. ...Upper Midwest... At least isolated strong to severe thunderstorms can be expected within a narrow corridor near the east/southeastward-moving front this afternoon from north-central MN southwestward into eastern SD, This will be influenced by the amplifying upper-level trough approaching the Dakotas/northern MN. The strongest winds aloft/vertical shear will tend to lag the front, but ample near/pre-frontal buoyancy will support storms capable of hail/wind. ..Mosier/Lyons.. 07/11/2025 Read more

SPC Jul 11, 2025 1630 UTC Day 1 Convective Outlook

1 month ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1131 AM CDT Fri Jul 11 2025 Valid 111630Z - 121200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM FAR NORTHEAST MO AND SOUTHEAST IA INTO NORTHWEST IL... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL AND SOUTHERN HIGH PLAINS... ...SUMMARY... Severe thunderstorms are expected this afternoon and evening across the Midwest to southern portions of the Great Lakes region, accompanied by a risk for damaging wind gusts, hail, as well as some tornado potential. Severe thunderstorms are also expected across the central/southern High Plains and Upper Midwest. ...Lower MO and Mid MS Valleys into Great Lakes... Recent surface analysis places a low over far southeast NE. Residual cloudiness and showers northeast of this low are helping to reinforce a warm-front-like baroclinic zone that extends from low eastward along the IA/MO border through central IL and IN. This boundary will likely sharpen throughout the day as the cloudiness and showers persist to its north and temperatures warm into 90s to its south. As a result, a reservoir of strong buoyancy is anticipated south of this boundary from southern IA into northern/central MO and western IL. Lift associated with the surface low, as well as its parent convectively augmented shortwave trough, will interact with this destabilized and buoyant airmass to support thunderstorm development by the early afternoon. Moderate vertical shear will be in place throughout the base of the shortwave, helping to organize some of these storms. However, the corridor of strongest shear is relatively narrow, with the broader environment characterized by weak mid-level flow and limited vertical shear. As such, a somewhat messy convection evolution appears probable. Initial development is expected over southern IA during the early afternoon. This activity will likely be elevated just north of the warm front. Additional warm sector development is also possible farther east across west-central/northwest IL. This initial development could be more cellular, with both hail and damaging gusts as primary risks. However, given the presence of a surface low as well as the warm front, some tornado risk is possible with these initially more cellular storms as well. Convective coverage is expected to increase with overall evolution towards a more linear mode anticipated with time. Damaging wind gusts should become the more predominant potential hazard as this occurs with the line moving east/southeastward this evening. Threat for brief embedded tornadoes exists within this evolving convective line as well. ...Central High Plains... The immediate post-frontal regime should be favorable for severe storm development this afternoon into evening across southeast WY and northeast CO into adjacent southwest NE/northwest KS. Some initial supercells capable of large hail can be expected, and one or more eastward-moving clusters may evolve by evening with severe-caliber winds also a possibility. ...Southern High Plains... Moderate low-level moisture (i.e. dewpoints in the upper 50 to low 60s) is currently in place across eastern NM, which will help offset some of the mixing anticipated as the airmass heats into the 90s this afternoon. Thunderstorm development is anticipated across the higher terrain of central/northern NM and the Raton Mesa, with these storms then progressing eastward/southeastward into the moderately moist, deeply mixed, and unstable airmass downstream across the southern High Plains. Numerous thunderstorms are expected, with the higher storm coverage likely facilitating cold pool amalgamation and the development of one or more forward-propagating convective clusters. Strong wind gusts would be possible within these clusters, with severe coverage expected to be high enough to merit introducing 15% wind probabilities. ...Upper Midwest... At least isolated strong to severe thunderstorms can be expected within a narrow corridor near the east/southeastward-moving front this afternoon from north-central MN southwestward into eastern SD, This will be influenced by the amplifying upper-level trough approaching the Dakotas/northern MN. The strongest winds aloft/vertical shear will tend to lag the front, but ample near/pre-frontal buoyancy will support storms capable of hail/wind. ..Mosier/Lyons.. 07/11/2025 Read more

SPC Jul 11, 2025 1630 UTC Day 1 Convective Outlook

1 month ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1131 AM CDT Fri Jul 11 2025 Valid 111630Z - 121200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM FAR NORTHEAST MO AND SOUTHEAST IA INTO NORTHWEST IL... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL AND SOUTHERN HIGH PLAINS... ...SUMMARY... Severe thunderstorms are expected this afternoon and evening across the Midwest to southern portions of the Great Lakes region, accompanied by a risk for damaging wind gusts, hail, as well as some tornado potential. Severe thunderstorms are also expected across the central/southern High Plains and Upper Midwest. ...Lower MO and Mid MS Valleys into Great Lakes... Recent surface analysis places a low over far southeast NE. Residual cloudiness and showers northeast of this low are helping to reinforce a warm-front-like baroclinic zone that extends from low eastward along the IA/MO border through central IL and IN. This boundary will likely sharpen throughout the day as the cloudiness and showers persist to its north and temperatures warm into 90s to its south. As a result, a reservoir of strong buoyancy is anticipated south of this boundary from southern IA into northern/central MO and western IL. Lift associated with the surface low, as well as its parent convectively augmented shortwave trough, will interact with this destabilized and buoyant airmass to support thunderstorm development by the early afternoon. Moderate vertical shear will be in place throughout the base of the shortwave, helping to organize some of these storms. However, the corridor of strongest shear is relatively narrow, with the broader environment characterized by weak mid-level flow and limited vertical shear. As such, a somewhat messy convection evolution appears probable. Initial development is expected over southern IA during the early afternoon. This activity will likely be elevated just north of the warm front. Additional warm sector development is also possible farther east across west-central/northwest IL. This initial development could be more cellular, with both hail and damaging gusts as primary risks. However, given the presence of a surface low as well as the warm front, some tornado risk is possible with these initially more cellular storms as well. Convective coverage is expected to increase with overall evolution towards a more linear mode anticipated with time. Damaging wind gusts should become the more predominant potential hazard as this occurs with the line moving east/southeastward this evening. Threat for brief embedded tornadoes exists within this evolving convective line as well. ...Central High Plains... The immediate post-frontal regime should be favorable for severe storm development this afternoon into evening across southeast WY and northeast CO into adjacent southwest NE/northwest KS. Some initial supercells capable of large hail can be expected, and one or more eastward-moving clusters may evolve by evening with severe-caliber winds also a possibility. ...Southern High Plains... Moderate low-level moisture (i.e. dewpoints in the upper 50 to low 60s) is currently in place across eastern NM, which will help offset some of the mixing anticipated as the airmass heats into the 90s this afternoon. Thunderstorm development is anticipated across the higher terrain of central/northern NM and the Raton Mesa, with these storms then progressing eastward/southeastward into the moderately moist, deeply mixed, and unstable airmass downstream across the southern High Plains. Numerous thunderstorms are expected, with the higher storm coverage likely facilitating cold pool amalgamation and the development of one or more forward-propagating convective clusters. Strong wind gusts would be possible within these clusters, with severe coverage expected to be high enough to merit introducing 15% wind probabilities. ...Upper Midwest... At least isolated strong to severe thunderstorms can be expected within a narrow corridor near the east/southeastward-moving front this afternoon from north-central MN southwestward into eastern SD, This will be influenced by the amplifying upper-level trough approaching the Dakotas/northern MN. The strongest winds aloft/vertical shear will tend to lag the front, but ample near/pre-frontal buoyancy will support storms capable of hail/wind. ..Mosier/Lyons.. 07/11/2025 Read more

SPC Jul 11, 2025 1630 UTC Day 1 Convective Outlook

1 month ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1131 AM CDT Fri Jul 11 2025 Valid 111630Z - 121200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM FAR NORTHEAST MO AND SOUTHEAST IA INTO NORTHWEST IL... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL AND SOUTHERN HIGH PLAINS... ...SUMMARY... Severe thunderstorms are expected this afternoon and evening across the Midwest to southern portions of the Great Lakes region, accompanied by a risk for damaging wind gusts, hail, as well as some tornado potential. Severe thunderstorms are also expected across the central/southern High Plains and Upper Midwest. ...Lower MO and Mid MS Valleys into Great Lakes... Recent surface analysis places a low over far southeast NE. Residual cloudiness and showers northeast of this low are helping to reinforce a warm-front-like baroclinic zone that extends from low eastward along the IA/MO border through central IL and IN. This boundary will likely sharpen throughout the day as the cloudiness and showers persist to its north and temperatures warm into 90s to its south. As a result, a reservoir of strong buoyancy is anticipated south of this boundary from southern IA into northern/central MO and western IL. Lift associated with the surface low, as well as its parent convectively augmented shortwave trough, will interact with this destabilized and buoyant airmass to support thunderstorm development by the early afternoon. Moderate vertical shear will be in place throughout the base of the shortwave, helping to organize some of these storms. However, the corridor of strongest shear is relatively narrow, with the broader environment characterized by weak mid-level flow and limited vertical shear. As such, a somewhat messy convection evolution appears probable. Initial development is expected over southern IA during the early afternoon. This activity will likely be elevated just north of the warm front. Additional warm sector development is also possible farther east across west-central/northwest IL. This initial development could be more cellular, with both hail and damaging gusts as primary risks. However, given the presence of a surface low as well as the warm front, some tornado risk is possible with these initially more cellular storms as well. Convective coverage is expected to increase with overall evolution towards a more linear mode anticipated with time. Damaging wind gusts should become the more predominant potential hazard as this occurs with the line moving east/southeastward this evening. Threat for brief embedded tornadoes exists within this evolving convective line as well. ...Central High Plains... The immediate post-frontal regime should be favorable for severe storm development this afternoon into evening across southeast WY and northeast CO into adjacent southwest NE/northwest KS. Some initial supercells capable of large hail can be expected, and one or more eastward-moving clusters may evolve by evening with severe-caliber winds also a possibility. ...Southern High Plains... Moderate low-level moisture (i.e. dewpoints in the upper 50 to low 60s) is currently in place across eastern NM, which will help offset some of the mixing anticipated as the airmass heats into the 90s this afternoon. Thunderstorm development is anticipated across the higher terrain of central/northern NM and the Raton Mesa, with these storms then progressing eastward/southeastward into the moderately moist, deeply mixed, and unstable airmass downstream across the southern High Plains. Numerous thunderstorms are expected, with the higher storm coverage likely facilitating cold pool amalgamation and the development of one or more forward-propagating convective clusters. Strong wind gusts would be possible within these clusters, with severe coverage expected to be high enough to merit introducing 15% wind probabilities. ...Upper Midwest... At least isolated strong to severe thunderstorms can be expected within a narrow corridor near the east/southeastward-moving front this afternoon from north-central MN southwestward into eastern SD, This will be influenced by the amplifying upper-level trough approaching the Dakotas/northern MN. The strongest winds aloft/vertical shear will tend to lag the front, but ample near/pre-frontal buoyancy will support storms capable of hail/wind. ..Mosier/Lyons.. 07/11/2025 Read more

SPC Jul 11, 2025 1630 UTC Day 1 Convective Outlook

1 month ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1131 AM CDT Fri Jul 11 2025 Valid 111630Z - 121200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM FAR NORTHEAST MO AND SOUTHEAST IA INTO NORTHWEST IL... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL AND SOUTHERN HIGH PLAINS... ...SUMMARY... Severe thunderstorms are expected this afternoon and evening across the Midwest to southern portions of the Great Lakes region, accompanied by a risk for damaging wind gusts, hail, as well as some tornado potential. Severe thunderstorms are also expected across the central/southern High Plains and Upper Midwest. ...Lower MO and Mid MS Valleys into Great Lakes... Recent surface analysis places a low over far southeast NE. Residual cloudiness and showers northeast of this low are helping to reinforce a warm-front-like baroclinic zone that extends from low eastward along the IA/MO border through central IL and IN. This boundary will likely sharpen throughout the day as the cloudiness and showers persist to its north and temperatures warm into 90s to its south. As a result, a reservoir of strong buoyancy is anticipated south of this boundary from southern IA into northern/central MO and western IL. Lift associated with the surface low, as well as its parent convectively augmented shortwave trough, will interact with this destabilized and buoyant airmass to support thunderstorm development by the early afternoon. Moderate vertical shear will be in place throughout the base of the shortwave, helping to organize some of these storms. However, the corridor of strongest shear is relatively narrow, with the broader environment characterized by weak mid-level flow and limited vertical shear. As such, a somewhat messy convection evolution appears probable. Initial development is expected over southern IA during the early afternoon. This activity will likely be elevated just north of the warm front. Additional warm sector development is also possible farther east across west-central/northwest IL. This initial development could be more cellular, with both hail and damaging gusts as primary risks. However, given the presence of a surface low as well as the warm front, some tornado risk is possible with these initially more cellular storms as well. Convective coverage is expected to increase with overall evolution towards a more linear mode anticipated with time. Damaging wind gusts should become the more predominant potential hazard as this occurs with the line moving east/southeastward this evening. Threat for brief embedded tornadoes exists within this evolving convective line as well. ...Central High Plains... The immediate post-frontal regime should be favorable for severe storm development this afternoon into evening across southeast WY and northeast CO into adjacent southwest NE/northwest KS. Some initial supercells capable of large hail can be expected, and one or more eastward-moving clusters may evolve by evening with severe-caliber winds also a possibility. ...Southern High Plains... Moderate low-level moisture (i.e. dewpoints in the upper 50 to low 60s) is currently in place across eastern NM, which will help offset some of the mixing anticipated as the airmass heats into the 90s this afternoon. Thunderstorm development is anticipated across the higher terrain of central/northern NM and the Raton Mesa, with these storms then progressing eastward/southeastward into the moderately moist, deeply mixed, and unstable airmass downstream across the southern High Plains. Numerous thunderstorms are expected, with the higher storm coverage likely facilitating cold pool amalgamation and the development of one or more forward-propagating convective clusters. Strong wind gusts would be possible within these clusters, with severe coverage expected to be high enough to merit introducing 15% wind probabilities. ...Upper Midwest... At least isolated strong to severe thunderstorms can be expected within a narrow corridor near the east/southeastward-moving front this afternoon from north-central MN southwestward into eastern SD, This will be influenced by the amplifying upper-level trough approaching the Dakotas/northern MN. The strongest winds aloft/vertical shear will tend to lag the front, but ample near/pre-frontal buoyancy will support storms capable of hail/wind. ..Mosier/Lyons.. 07/11/2025 Read more

SPC Jul 11, 2025 1630 UTC Day 1 Convective Outlook

1 month ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1131 AM CDT Fri Jul 11 2025 Valid 111630Z - 121200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM FAR NORTHEAST MO AND SOUTHEAST IA INTO NORTHWEST IL... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL AND SOUTHERN HIGH PLAINS... ...SUMMARY... Severe thunderstorms are expected this afternoon and evening across the Midwest to southern portions of the Great Lakes region, accompanied by a risk for damaging wind gusts, hail, as well as some tornado potential. Severe thunderstorms are also expected across the central/southern High Plains and Upper Midwest. ...Lower MO and Mid MS Valleys into Great Lakes... Recent surface analysis places a low over far southeast NE. Residual cloudiness and showers northeast of this low are helping to reinforce a warm-front-like baroclinic zone that extends from low eastward along the IA/MO border through central IL and IN. This boundary will likely sharpen throughout the day as the cloudiness and showers persist to its north and temperatures warm into 90s to its south. As a result, a reservoir of strong buoyancy is anticipated south of this boundary from southern IA into northern/central MO and western IL. Lift associated with the surface low, as well as its parent convectively augmented shortwave trough, will interact with this destabilized and buoyant airmass to support thunderstorm development by the early afternoon. Moderate vertical shear will be in place throughout the base of the shortwave, helping to organize some of these storms. However, the corridor of strongest shear is relatively narrow, with the broader environment characterized by weak mid-level flow and limited vertical shear. As such, a somewhat messy convection evolution appears probable. Initial development is expected over southern IA during the early afternoon. This activity will likely be elevated just north of the warm front. Additional warm sector development is also possible farther east across west-central/northwest IL. This initial development could be more cellular, with both hail and damaging gusts as primary risks. However, given the presence of a surface low as well as the warm front, some tornado risk is possible with these initially more cellular storms as well. Convective coverage is expected to increase with overall evolution towards a more linear mode anticipated with time. Damaging wind gusts should become the more predominant potential hazard as this occurs with the line moving east/southeastward this evening. Threat for brief embedded tornadoes exists within this evolving convective line as well. ...Central High Plains... The immediate post-frontal regime should be favorable for severe storm development this afternoon into evening across southeast WY and northeast CO into adjacent southwest NE/northwest KS. Some initial supercells capable of large hail can be expected, and one or more eastward-moving clusters may evolve by evening with severe-caliber winds also a possibility. ...Southern High Plains... Moderate low-level moisture (i.e. dewpoints in the upper 50 to low 60s) is currently in place across eastern NM, which will help offset some of the mixing anticipated as the airmass heats into the 90s this afternoon. Thunderstorm development is anticipated across the higher terrain of central/northern NM and the Raton Mesa, with these storms then progressing eastward/southeastward into the moderately moist, deeply mixed, and unstable airmass downstream across the southern High Plains. Numerous thunderstorms are expected, with the higher storm coverage likely facilitating cold pool amalgamation and the development of one or more forward-propagating convective clusters. Strong wind gusts would be possible within these clusters, with severe coverage expected to be high enough to merit introducing 15% wind probabilities. ...Upper Midwest... At least isolated strong to severe thunderstorms can be expected within a narrow corridor near the east/southeastward-moving front this afternoon from north-central MN southwestward into eastern SD, This will be influenced by the amplifying upper-level trough approaching the Dakotas/northern MN. The strongest winds aloft/vertical shear will tend to lag the front, but ample near/pre-frontal buoyancy will support storms capable of hail/wind. ..Mosier/Lyons.. 07/11/2025 Read more

SPC Jul 11, 2025 1630 UTC Day 1 Convective Outlook

1 month ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1131 AM CDT Fri Jul 11 2025 Valid 111630Z - 121200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM FAR NORTHEAST MO AND SOUTHEAST IA INTO NORTHWEST IL... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL AND SOUTHERN HIGH PLAINS... ...SUMMARY... Severe thunderstorms are expected this afternoon and evening across the Midwest to southern portions of the Great Lakes region, accompanied by a risk for damaging wind gusts, hail, as well as some tornado potential. Severe thunderstorms are also expected across the central/southern High Plains and Upper Midwest. ...Lower MO and Mid MS Valleys into Great Lakes... Recent surface analysis places a low over far southeast NE. Residual cloudiness and showers northeast of this low are helping to reinforce a warm-front-like baroclinic zone that extends from low eastward along the IA/MO border through central IL and IN. This boundary will likely sharpen throughout the day as the cloudiness and showers persist to its north and temperatures warm into 90s to its south. As a result, a reservoir of strong buoyancy is anticipated south of this boundary from southern IA into northern/central MO and western IL. Lift associated with the surface low, as well as its parent convectively augmented shortwave trough, will interact with this destabilized and buoyant airmass to support thunderstorm development by the early afternoon. Moderate vertical shear will be in place throughout the base of the shortwave, helping to organize some of these storms. However, the corridor of strongest shear is relatively narrow, with the broader environment characterized by weak mid-level flow and limited vertical shear. As such, a somewhat messy convection evolution appears probable. Initial development is expected over southern IA during the early afternoon. This activity will likely be elevated just north of the warm front. Additional warm sector development is also possible farther east across west-central/northwest IL. This initial development could be more cellular, with both hail and damaging gusts as primary risks. However, given the presence of a surface low as well as the warm front, some tornado risk is possible with these initially more cellular storms as well. Convective coverage is expected to increase with overall evolution towards a more linear mode anticipated with time. Damaging wind gusts should become the more predominant potential hazard as this occurs with the line moving east/southeastward this evening. Threat for brief embedded tornadoes exists within this evolving convective line as well. ...Central High Plains... The immediate post-frontal regime should be favorable for severe storm development this afternoon into evening across southeast WY and northeast CO into adjacent southwest NE/northwest KS. Some initial supercells capable of large hail can be expected, and one or more eastward-moving clusters may evolve by evening with severe-caliber winds also a possibility. ...Southern High Plains... Moderate low-level moisture (i.e. dewpoints in the upper 50 to low 60s) is currently in place across eastern NM, which will help offset some of the mixing anticipated as the airmass heats into the 90s this afternoon. Thunderstorm development is anticipated across the higher terrain of central/northern NM and the Raton Mesa, with these storms then progressing eastward/southeastward into the moderately moist, deeply mixed, and unstable airmass downstream across the southern High Plains. Numerous thunderstorms are expected, with the higher storm coverage likely facilitating cold pool amalgamation and the development of one or more forward-propagating convective clusters. Strong wind gusts would be possible within these clusters, with severe coverage expected to be high enough to merit introducing 15% wind probabilities. ...Upper Midwest... At least isolated strong to severe thunderstorms can be expected within a narrow corridor near the east/southeastward-moving front this afternoon from north-central MN southwestward into eastern SD, This will be influenced by the amplifying upper-level trough approaching the Dakotas/northern MN. The strongest winds aloft/vertical shear will tend to lag the front, but ample near/pre-frontal buoyancy will support storms capable of hail/wind. ..Mosier/Lyons.. 07/11/2025 Read more

SPC Jul 11, 2025 1630 UTC Day 1 Convective Outlook

1 month ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1131 AM CDT Fri Jul 11 2025 Valid 111630Z - 121200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM FAR NORTHEAST MO AND SOUTHEAST IA INTO NORTHWEST IL... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL AND SOUTHERN HIGH PLAINS... ...SUMMARY... Severe thunderstorms are expected this afternoon and evening across the Midwest to southern portions of the Great Lakes region, accompanied by a risk for damaging wind gusts, hail, as well as some tornado potential. Severe thunderstorms are also expected across the central/southern High Plains and Upper Midwest. ...Lower MO and Mid MS Valleys into Great Lakes... Recent surface analysis places a low over far southeast NE. Residual cloudiness and showers northeast of this low are helping to reinforce a warm-front-like baroclinic zone that extends from low eastward along the IA/MO border through central IL and IN. This boundary will likely sharpen throughout the day as the cloudiness and showers persist to its north and temperatures warm into 90s to its south. As a result, a reservoir of strong buoyancy is anticipated south of this boundary from southern IA into northern/central MO and western IL. Lift associated with the surface low, as well as its parent convectively augmented shortwave trough, will interact with this destabilized and buoyant airmass to support thunderstorm development by the early afternoon. Moderate vertical shear will be in place throughout the base of the shortwave, helping to organize some of these storms. However, the corridor of strongest shear is relatively narrow, with the broader environment characterized by weak mid-level flow and limited vertical shear. As such, a somewhat messy convection evolution appears probable. Initial development is expected over southern IA during the early afternoon. This activity will likely be elevated just north of the warm front. Additional warm sector development is also possible farther east across west-central/northwest IL. This initial development could be more cellular, with both hail and damaging gusts as primary risks. However, given the presence of a surface low as well as the warm front, some tornado risk is possible with these initially more cellular storms as well. Convective coverage is expected to increase with overall evolution towards a more linear mode anticipated with time. Damaging wind gusts should become the more predominant potential hazard as this occurs with the line moving east/southeastward this evening. Threat for brief embedded tornadoes exists within this evolving convective line as well. ...Central High Plains... The immediate post-frontal regime should be favorable for severe storm development this afternoon into evening across southeast WY and northeast CO into adjacent southwest NE/northwest KS. Some initial supercells capable of large hail can be expected, and one or more eastward-moving clusters may evolve by evening with severe-caliber winds also a possibility. ...Southern High Plains... Moderate low-level moisture (i.e. dewpoints in the upper 50 to low 60s) is currently in place across eastern NM, which will help offset some of the mixing anticipated as the airmass heats into the 90s this afternoon. Thunderstorm development is anticipated across the higher terrain of central/northern NM and the Raton Mesa, with these storms then progressing eastward/southeastward into the moderately moist, deeply mixed, and unstable airmass downstream across the southern High Plains. Numerous thunderstorms are expected, with the higher storm coverage likely facilitating cold pool amalgamation and the development of one or more forward-propagating convective clusters. Strong wind gusts would be possible within these clusters, with severe coverage expected to be high enough to merit introducing 15% wind probabilities. ...Upper Midwest... At least isolated strong to severe thunderstorms can be expected within a narrow corridor near the east/southeastward-moving front this afternoon from north-central MN southwestward into eastern SD, This will be influenced by the amplifying upper-level trough approaching the Dakotas/northern MN. The strongest winds aloft/vertical shear will tend to lag the front, but ample near/pre-frontal buoyancy will support storms capable of hail/wind. ..Mosier/Lyons.. 07/11/2025 Read more

SPC Jul 11, 2025 1630 UTC Day 1 Convective Outlook

1 month ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1131 AM CDT Fri Jul 11 2025 Valid 111630Z - 121200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM FAR NORTHEAST MO AND SOUTHEAST IA INTO NORTHWEST IL... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL AND SOUTHERN HIGH PLAINS... ...SUMMARY... Severe thunderstorms are expected this afternoon and evening across the Midwest to southern portions of the Great Lakes region, accompanied by a risk for damaging wind gusts, hail, as well as some tornado potential. Severe thunderstorms are also expected across the central/southern High Plains and Upper Midwest. ...Lower MO and Mid MS Valleys into Great Lakes... Recent surface analysis places a low over far southeast NE. Residual cloudiness and showers northeast of this low are helping to reinforce a warm-front-like baroclinic zone that extends from low eastward along the IA/MO border through central IL and IN. This boundary will likely sharpen throughout the day as the cloudiness and showers persist to its north and temperatures warm into 90s to its south. As a result, a reservoir of strong buoyancy is anticipated south of this boundary from southern IA into northern/central MO and western IL. Lift associated with the surface low, as well as its parent convectively augmented shortwave trough, will interact with this destabilized and buoyant airmass to support thunderstorm development by the early afternoon. Moderate vertical shear will be in place throughout the base of the shortwave, helping to organize some of these storms. However, the corridor of strongest shear is relatively narrow, with the broader environment characterized by weak mid-level flow and limited vertical shear. As such, a somewhat messy convection evolution appears probable. Initial development is expected over southern IA during the early afternoon. This activity will likely be elevated just north of the warm front. Additional warm sector development is also possible farther east across west-central/northwest IL. This initial development could be more cellular, with both hail and damaging gusts as primary risks. However, given the presence of a surface low as well as the warm front, some tornado risk is possible with these initially more cellular storms as well. Convective coverage is expected to increase with overall evolution towards a more linear mode anticipated with time. Damaging wind gusts should become the more predominant potential hazard as this occurs with the line moving east/southeastward this evening. Threat for brief embedded tornadoes exists within this evolving convective line as well. ...Central High Plains... The immediate post-frontal regime should be favorable for severe storm development this afternoon into evening across southeast WY and northeast CO into adjacent southwest NE/northwest KS. Some initial supercells capable of large hail can be expected, and one or more eastward-moving clusters may evolve by evening with severe-caliber winds also a possibility. ...Southern High Plains... Moderate low-level moisture (i.e. dewpoints in the upper 50 to low 60s) is currently in place across eastern NM, which will help offset some of the mixing anticipated as the airmass heats into the 90s this afternoon. Thunderstorm development is anticipated across the higher terrain of central/northern NM and the Raton Mesa, with these storms then progressing eastward/southeastward into the moderately moist, deeply mixed, and unstable airmass downstream across the southern High Plains. Numerous thunderstorms are expected, with the higher storm coverage likely facilitating cold pool amalgamation and the development of one or more forward-propagating convective clusters. Strong wind gusts would be possible within these clusters, with severe coverage expected to be high enough to merit introducing 15% wind probabilities. ...Upper Midwest... At least isolated strong to severe thunderstorms can be expected within a narrow corridor near the east/southeastward-moving front this afternoon from north-central MN southwestward into eastern SD, This will be influenced by the amplifying upper-level trough approaching the Dakotas/northern MN. The strongest winds aloft/vertical shear will tend to lag the front, but ample near/pre-frontal buoyancy will support storms capable of hail/wind. ..Mosier/Lyons.. 07/11/2025 Read more

SPC Jul 11, 2025 1630 UTC Day 1 Convective Outlook

1 month ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1131 AM CDT Fri Jul 11 2025 Valid 111630Z - 121200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM FAR NORTHEAST MO AND SOUTHEAST IA INTO NORTHWEST IL... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL AND SOUTHERN HIGH PLAINS... ...SUMMARY... Severe thunderstorms are expected this afternoon and evening across the Midwest to southern portions of the Great Lakes region, accompanied by a risk for damaging wind gusts, hail, as well as some tornado potential. Severe thunderstorms are also expected across the central/southern High Plains and Upper Midwest. ...Lower MO and Mid MS Valleys into Great Lakes... Recent surface analysis places a low over far southeast NE. Residual cloudiness and showers northeast of this low are helping to reinforce a warm-front-like baroclinic zone that extends from low eastward along the IA/MO border through central IL and IN. This boundary will likely sharpen throughout the day as the cloudiness and showers persist to its north and temperatures warm into 90s to its south. As a result, a reservoir of strong buoyancy is anticipated south of this boundary from southern IA into northern/central MO and western IL. Lift associated with the surface low, as well as its parent convectively augmented shortwave trough, will interact with this destabilized and buoyant airmass to support thunderstorm development by the early afternoon. Moderate vertical shear will be in place throughout the base of the shortwave, helping to organize some of these storms. However, the corridor of strongest shear is relatively narrow, with the broader environment characterized by weak mid-level flow and limited vertical shear. As such, a somewhat messy convection evolution appears probable. Initial development is expected over southern IA during the early afternoon. This activity will likely be elevated just north of the warm front. Additional warm sector development is also possible farther east across west-central/northwest IL. This initial development could be more cellular, with both hail and damaging gusts as primary risks. However, given the presence of a surface low as well as the warm front, some tornado risk is possible with these initially more cellular storms as well. Convective coverage is expected to increase with overall evolution towards a more linear mode anticipated with time. Damaging wind gusts should become the more predominant potential hazard as this occurs with the line moving east/southeastward this evening. Threat for brief embedded tornadoes exists within this evolving convective line as well. ...Central High Plains... The immediate post-frontal regime should be favorable for severe storm development this afternoon into evening across southeast WY and northeast CO into adjacent southwest NE/northwest KS. Some initial supercells capable of large hail can be expected, and one or more eastward-moving clusters may evolve by evening with severe-caliber winds also a possibility. ...Southern High Plains... Moderate low-level moisture (i.e. dewpoints in the upper 50 to low 60s) is currently in place across eastern NM, which will help offset some of the mixing anticipated as the airmass heats into the 90s this afternoon. Thunderstorm development is anticipated across the higher terrain of central/northern NM and the Raton Mesa, with these storms then progressing eastward/southeastward into the moderately moist, deeply mixed, and unstable airmass downstream across the southern High Plains. Numerous thunderstorms are expected, with the higher storm coverage likely facilitating cold pool amalgamation and the development of one or more forward-propagating convective clusters. Strong wind gusts would be possible within these clusters, with severe coverage expected to be high enough to merit introducing 15% wind probabilities. ...Upper Midwest... At least isolated strong to severe thunderstorms can be expected within a narrow corridor near the east/southeastward-moving front this afternoon from north-central MN southwestward into eastern SD, This will be influenced by the amplifying upper-level trough approaching the Dakotas/northern MN. The strongest winds aloft/vertical shear will tend to lag the front, but ample near/pre-frontal buoyancy will support storms capable of hail/wind. ..Mosier/Lyons.. 07/11/2025 Read more

SPC Jul 11, 2025 1630 UTC Day 1 Convective Outlook

1 month ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1131 AM CDT Fri Jul 11 2025 Valid 111630Z - 121200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM FAR NORTHEAST MO AND SOUTHEAST IA INTO NORTHWEST IL... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL AND SOUTHERN HIGH PLAINS... ...SUMMARY... Severe thunderstorms are expected this afternoon and evening across the Midwest to southern portions of the Great Lakes region, accompanied by a risk for damaging wind gusts, hail, as well as some tornado potential. Severe thunderstorms are also expected across the central/southern High Plains and Upper Midwest. ...Lower MO and Mid MS Valleys into Great Lakes... Recent surface analysis places a low over far southeast NE. Residual cloudiness and showers northeast of this low are helping to reinforce a warm-front-like baroclinic zone that extends from low eastward along the IA/MO border through central IL and IN. This boundary will likely sharpen throughout the day as the cloudiness and showers persist to its north and temperatures warm into 90s to its south. As a result, a reservoir of strong buoyancy is anticipated south of this boundary from southern IA into northern/central MO and western IL. Lift associated with the surface low, as well as its parent convectively augmented shortwave trough, will interact with this destabilized and buoyant airmass to support thunderstorm development by the early afternoon. Moderate vertical shear will be in place throughout the base of the shortwave, helping to organize some of these storms. However, the corridor of strongest shear is relatively narrow, with the broader environment characterized by weak mid-level flow and limited vertical shear. As such, a somewhat messy convection evolution appears probable. Initial development is expected over southern IA during the early afternoon. This activity will likely be elevated just north of the warm front. Additional warm sector development is also possible farther east across west-central/northwest IL. This initial development could be more cellular, with both hail and damaging gusts as primary risks. However, given the presence of a surface low as well as the warm front, some tornado risk is possible with these initially more cellular storms as well. Convective coverage is expected to increase with overall evolution towards a more linear mode anticipated with time. Damaging wind gusts should become the more predominant potential hazard as this occurs with the line moving east/southeastward this evening. Threat for brief embedded tornadoes exists within this evolving convective line as well. ...Central High Plains... The immediate post-frontal regime should be favorable for severe storm development this afternoon into evening across southeast WY and northeast CO into adjacent southwest NE/northwest KS. Some initial supercells capable of large hail can be expected, and one or more eastward-moving clusters may evolve by evening with severe-caliber winds also a possibility. ...Southern High Plains... Moderate low-level moisture (i.e. dewpoints in the upper 50 to low 60s) is currently in place across eastern NM, which will help offset some of the mixing anticipated as the airmass heats into the 90s this afternoon. Thunderstorm development is anticipated across the higher terrain of central/northern NM and the Raton Mesa, with these storms then progressing eastward/southeastward into the moderately moist, deeply mixed, and unstable airmass downstream across the southern High Plains. Numerous thunderstorms are expected, with the higher storm coverage likely facilitating cold pool amalgamation and the development of one or more forward-propagating convective clusters. Strong wind gusts would be possible within these clusters, with severe coverage expected to be high enough to merit introducing 15% wind probabilities. ...Upper Midwest... At least isolated strong to severe thunderstorms can be expected within a narrow corridor near the east/southeastward-moving front this afternoon from north-central MN southwestward into eastern SD, This will be influenced by the amplifying upper-level trough approaching the Dakotas/northern MN. The strongest winds aloft/vertical shear will tend to lag the front, but ample near/pre-frontal buoyancy will support storms capable of hail/wind. ..Mosier/Lyons.. 07/11/2025 Read more

SPC Jul 11, 2025 1630 UTC Day 1 Convective Outlook

1 month ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1131 AM CDT Fri Jul 11 2025 Valid 111630Z - 121200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM FAR NORTHEAST MO AND SOUTHEAST IA INTO NORTHWEST IL... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL AND SOUTHERN HIGH PLAINS... ...SUMMARY... Severe thunderstorms are expected this afternoon and evening across the Midwest to southern portions of the Great Lakes region, accompanied by a risk for damaging wind gusts, hail, as well as some tornado potential. Severe thunderstorms are also expected across the central/southern High Plains and Upper Midwest. ...Lower MO and Mid MS Valleys into Great Lakes... Recent surface analysis places a low over far southeast NE. Residual cloudiness and showers northeast of this low are helping to reinforce a warm-front-like baroclinic zone that extends from low eastward along the IA/MO border through central IL and IN. This boundary will likely sharpen throughout the day as the cloudiness and showers persist to its north and temperatures warm into 90s to its south. As a result, a reservoir of strong buoyancy is anticipated south of this boundary from southern IA into northern/central MO and western IL. Lift associated with the surface low, as well as its parent convectively augmented shortwave trough, will interact with this destabilized and buoyant airmass to support thunderstorm development by the early afternoon. Moderate vertical shear will be in place throughout the base of the shortwave, helping to organize some of these storms. However, the corridor of strongest shear is relatively narrow, with the broader environment characterized by weak mid-level flow and limited vertical shear. As such, a somewhat messy convection evolution appears probable. Initial development is expected over southern IA during the early afternoon. This activity will likely be elevated just north of the warm front. Additional warm sector development is also possible farther east across west-central/northwest IL. This initial development could be more cellular, with both hail and damaging gusts as primary risks. However, given the presence of a surface low as well as the warm front, some tornado risk is possible with these initially more cellular storms as well. Convective coverage is expected to increase with overall evolution towards a more linear mode anticipated with time. Damaging wind gusts should become the more predominant potential hazard as this occurs with the line moving east/southeastward this evening. Threat for brief embedded tornadoes exists within this evolving convective line as well. ...Central High Plains... The immediate post-frontal regime should be favorable for severe storm development this afternoon into evening across southeast WY and northeast CO into adjacent southwest NE/northwest KS. Some initial supercells capable of large hail can be expected, and one or more eastward-moving clusters may evolve by evening with severe-caliber winds also a possibility. ...Southern High Plains... Moderate low-level moisture (i.e. dewpoints in the upper 50 to low 60s) is currently in place across eastern NM, which will help offset some of the mixing anticipated as the airmass heats into the 90s this afternoon. Thunderstorm development is anticipated across the higher terrain of central/northern NM and the Raton Mesa, with these storms then progressing eastward/southeastward into the moderately moist, deeply mixed, and unstable airmass downstream across the southern High Plains. Numerous thunderstorms are expected, with the higher storm coverage likely facilitating cold pool amalgamation and the development of one or more forward-propagating convective clusters. Strong wind gusts would be possible within these clusters, with severe coverage expected to be high enough to merit introducing 15% wind probabilities. ...Upper Midwest... At least isolated strong to severe thunderstorms can be expected within a narrow corridor near the east/southeastward-moving front this afternoon from north-central MN southwestward into eastern SD, This will be influenced by the amplifying upper-level trough approaching the Dakotas/northern MN. The strongest winds aloft/vertical shear will tend to lag the front, but ample near/pre-frontal buoyancy will support storms capable of hail/wind. ..Mosier/Lyons.. 07/11/2025 Read more

SPC Jul 11, 2025 1630 UTC Day 1 Convective Outlook

1 month ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1131 AM CDT Fri Jul 11 2025 Valid 111630Z - 121200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM FAR NORTHEAST MO AND SOUTHEAST IA INTO NORTHWEST IL... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL AND SOUTHERN HIGH PLAINS... ...SUMMARY... Severe thunderstorms are expected this afternoon and evening across the Midwest to southern portions of the Great Lakes region, accompanied by a risk for damaging wind gusts, hail, as well as some tornado potential. Severe thunderstorms are also expected across the central/southern High Plains and Upper Midwest. ...Lower MO and Mid MS Valleys into Great Lakes... Recent surface analysis places a low over far southeast NE. Residual cloudiness and showers northeast of this low are helping to reinforce a warm-front-like baroclinic zone that extends from low eastward along the IA/MO border through central IL and IN. This boundary will likely sharpen throughout the day as the cloudiness and showers persist to its north and temperatures warm into 90s to its south. As a result, a reservoir of strong buoyancy is anticipated south of this boundary from southern IA into northern/central MO and western IL. Lift associated with the surface low, as well as its parent convectively augmented shortwave trough, will interact with this destabilized and buoyant airmass to support thunderstorm development by the early afternoon. Moderate vertical shear will be in place throughout the base of the shortwave, helping to organize some of these storms. However, the corridor of strongest shear is relatively narrow, with the broader environment characterized by weak mid-level flow and limited vertical shear. As such, a somewhat messy convection evolution appears probable. Initial development is expected over southern IA during the early afternoon. This activity will likely be elevated just north of the warm front. Additional warm sector development is also possible farther east across west-central/northwest IL. This initial development could be more cellular, with both hail and damaging gusts as primary risks. However, given the presence of a surface low as well as the warm front, some tornado risk is possible with these initially more cellular storms as well. Convective coverage is expected to increase with overall evolution towards a more linear mode anticipated with time. Damaging wind gusts should become the more predominant potential hazard as this occurs with the line moving east/southeastward this evening. Threat for brief embedded tornadoes exists within this evolving convective line as well. ...Central High Plains... The immediate post-frontal regime should be favorable for severe storm development this afternoon into evening across southeast WY and northeast CO into adjacent southwest NE/northwest KS. Some initial supercells capable of large hail can be expected, and one or more eastward-moving clusters may evolve by evening with severe-caliber winds also a possibility. ...Southern High Plains... Moderate low-level moisture (i.e. dewpoints in the upper 50 to low 60s) is currently in place across eastern NM, which will help offset some of the mixing anticipated as the airmass heats into the 90s this afternoon. Thunderstorm development is anticipated across the higher terrain of central/northern NM and the Raton Mesa, with these storms then progressing eastward/southeastward into the moderately moist, deeply mixed, and unstable airmass downstream across the southern High Plains. Numerous thunderstorms are expected, with the higher storm coverage likely facilitating cold pool amalgamation and the development of one or more forward-propagating convective clusters. Strong wind gusts would be possible within these clusters, with severe coverage expected to be high enough to merit introducing 15% wind probabilities. ...Upper Midwest... At least isolated strong to severe thunderstorms can be expected within a narrow corridor near the east/southeastward-moving front this afternoon from north-central MN southwestward into eastern SD, This will be influenced by the amplifying upper-level trough approaching the Dakotas/northern MN. The strongest winds aloft/vertical shear will tend to lag the front, but ample near/pre-frontal buoyancy will support storms capable of hail/wind. ..Mosier/Lyons.. 07/11/2025 Read more

SPC Jul 11, 2025 1630 UTC Day 1 Convective Outlook

1 month ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1131 AM CDT Fri Jul 11 2025 Valid 111630Z - 121200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM FAR NORTHEAST MO AND SOUTHEAST IA INTO NORTHWEST IL... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL AND SOUTHERN HIGH PLAINS... ...SUMMARY... Severe thunderstorms are expected this afternoon and evening across the Midwest to southern portions of the Great Lakes region, accompanied by a risk for damaging wind gusts, hail, as well as some tornado potential. Severe thunderstorms are also expected across the central/southern High Plains and Upper Midwest. ...Lower MO and Mid MS Valleys into Great Lakes... Recent surface analysis places a low over far southeast NE. Residual cloudiness and showers northeast of this low are helping to reinforce a warm-front-like baroclinic zone that extends from low eastward along the IA/MO border through central IL and IN. This boundary will likely sharpen throughout the day as the cloudiness and showers persist to its north and temperatures warm into 90s to its south. As a result, a reservoir of strong buoyancy is anticipated south of this boundary from southern IA into northern/central MO and western IL. Lift associated with the surface low, as well as its parent convectively augmented shortwave trough, will interact with this destabilized and buoyant airmass to support thunderstorm development by the early afternoon. Moderate vertical shear will be in place throughout the base of the shortwave, helping to organize some of these storms. However, the corridor of strongest shear is relatively narrow, with the broader environment characterized by weak mid-level flow and limited vertical shear. As such, a somewhat messy convection evolution appears probable. Initial development is expected over southern IA during the early afternoon. This activity will likely be elevated just north of the warm front. Additional warm sector development is also possible farther east across west-central/northwest IL. This initial development could be more cellular, with both hail and damaging gusts as primary risks. However, given the presence of a surface low as well as the warm front, some tornado risk is possible with these initially more cellular storms as well. Convective coverage is expected to increase with overall evolution towards a more linear mode anticipated with time. Damaging wind gusts should become the more predominant potential hazard as this occurs with the line moving east/southeastward this evening. Threat for brief embedded tornadoes exists within this evolving convective line as well. ...Central High Plains... The immediate post-frontal regime should be favorable for severe storm development this afternoon into evening across southeast WY and northeast CO into adjacent southwest NE/northwest KS. Some initial supercells capable of large hail can be expected, and one or more eastward-moving clusters may evolve by evening with severe-caliber winds also a possibility. ...Southern High Plains... Moderate low-level moisture (i.e. dewpoints in the upper 50 to low 60s) is currently in place across eastern NM, which will help offset some of the mixing anticipated as the airmass heats into the 90s this afternoon. Thunderstorm development is anticipated across the higher terrain of central/northern NM and the Raton Mesa, with these storms then progressing eastward/southeastward into the moderately moist, deeply mixed, and unstable airmass downstream across the southern High Plains. Numerous thunderstorms are expected, with the higher storm coverage likely facilitating cold pool amalgamation and the development of one or more forward-propagating convective clusters. Strong wind gusts would be possible within these clusters, with severe coverage expected to be high enough to merit introducing 15% wind probabilities. ...Upper Midwest... At least isolated strong to severe thunderstorms can be expected within a narrow corridor near the east/southeastward-moving front this afternoon from north-central MN southwestward into eastern SD, This will be influenced by the amplifying upper-level trough approaching the Dakotas/northern MN. The strongest winds aloft/vertical shear will tend to lag the front, but ample near/pre-frontal buoyancy will support storms capable of hail/wind. ..Mosier/Lyons.. 07/11/2025 Read more

SPC Jul 11, 2025 1630 UTC Day 1 Convective Outlook

1 month ago
SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1131 AM CDT Fri Jul 11 2025 Valid 111630Z - 121200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM FAR NORTHEAST MO AND SOUTHEAST IA INTO NORTHWEST IL... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL AND SOUTHERN HIGH PLAINS... ...SUMMARY... Severe thunderstorms are expected this afternoon and evening across the Midwest to southern portions of the Great Lakes region, accompanied by a risk for damaging wind gusts, hail, as well as some tornado potential. Severe thunderstorms are also expected across the central/southern High Plains and Upper Midwest. ...Lower MO and Mid MS Valleys into Great Lakes... Recent surface analysis places a low over far southeast NE. Residual cloudiness and showers northeast of this low are helping to reinforce a warm-front-like baroclinic zone that extends from low eastward along the IA/MO border through central IL and IN. This boundary will likely sharpen throughout the day as the cloudiness and showers persist to its north and temperatures warm into 90s to its south. As a result, a reservoir of strong buoyancy is anticipated south of this boundary from southern IA into northern/central MO and western IL. Lift associated with the surface low, as well as its parent convectively augmented shortwave trough, will interact with this destabilized and buoyant airmass to support thunderstorm development by the early afternoon. Moderate vertical shear will be in place throughout the base of the shortwave, helping to organize some of these storms. However, the corridor of strongest shear is relatively narrow, with the broader environment characterized by weak mid-level flow and limited vertical shear. As such, a somewhat messy convection evolution appears probable. Initial development is expected over southern IA during the early afternoon. This activity will likely be elevated just north of the warm front. Additional warm sector development is also possible farther east across west-central/northwest IL. This initial development could be more cellular, with both hail and damaging gusts as primary risks. However, given the presence of a surface low as well as the warm front, some tornado risk is possible with these initially more cellular storms as well. Convective coverage is expected to increase with overall evolution towards a more linear mode anticipated with time. Damaging wind gusts should become the more predominant potential hazard as this occurs with the line moving east/southeastward this evening. Threat for brief embedded tornadoes exists within this evolving convective line as well. ...Central High Plains... The immediate post-frontal regime should be favorable for severe storm development this afternoon into evening across southeast WY and northeast CO into adjacent southwest NE/northwest KS. Some initial supercells capable of large hail can be expected, and one or more eastward-moving clusters may evolve by evening with severe-caliber winds also a possibility. ...Southern High Plains... Moderate low-level moisture (i.e. dewpoints in the upper 50 to low 60s) is currently in place across eastern NM, which will help offset some of the mixing anticipated as the airmass heats into the 90s this afternoon. Thunderstorm development is anticipated across the higher terrain of central/northern NM and the Raton Mesa, with these storms then progressing eastward/southeastward into the moderately moist, deeply mixed, and unstable airmass downstream across the southern High Plains. Numerous thunderstorms are expected, with the higher storm coverage likely facilitating cold pool amalgamation and the development of one or more forward-propagating convective clusters. Strong wind gusts would be possible within these clusters, with severe coverage expected to be high enough to merit introducing 15% wind probabilities. ...Upper Midwest... At least isolated strong to severe thunderstorms can be expected within a narrow corridor near the east/southeastward-moving front this afternoon from north-central MN southwestward into eastern SD, This will be influenced by the amplifying upper-level trough approaching the Dakotas/northern MN. The strongest winds aloft/vertical shear will tend to lag the front, but ample near/pre-frontal buoyancy will support storms capable of hail/wind. ..Mosier/Lyons.. 07/11/2025 Read more