SPC Jul 13, 2025 2000 UTC Day 1 Convective Outlook

1 month ago
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0250 PM CDT Sun Jul 13 2025 Valid 132000Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS SOUTHEAST ARIZONA...CENTRAL PENNSYLVANIA INTO NORTHERN NEW YORK... ...SUMMARY... Isolated severe thunderstorms are possible today through early tonight in the Upper Midwest, Mid-Atlantic/Northeast, Southwest, south-central Texas to the Lower Ohio Valley, and Florida. ...20Z Update... Adjustments were made to the general thunderstorm area based on current observations. The forecast is otherwise unchanged. See the previous forecast for additional details. ..Wendt.. 07/13/2025 .PREV DISCUSSION... /ISSUED 1128 AM CDT Sun Jul 13 2025/ ...Northeast/Mid-Atlantic States... Moist low-level convergence, orographic effects, and glancing ascent from an exiting shortwave trough will combine to support widespread thunderstorm development from western/central NY southward into central VA today. Shear is weak across much of the region, with a generally disorganized multicellular mode anticipated. As such, water-loaded downbursts will be the primary risk. However, modestly stronger mid-level southwesterlies could support some sustained multicells from central/northern NY into central PA. Consequently, there is corridor of greater severe potential across this region where storm clustering and linear segments appear more likely. ...Southwest... Modest northerly flow aloft is forecast across northern NM, turning more northeasterly over southeast AZ. Widespread storms are expected to develop off the higher terrain and then progress southward/southwestward from mid-afternoon to mid-evening. Given moderate northeasterly flow, the potential for strong gusts exists, particularly across southeast AZ, where high-based storms coming off the higher terrain will move into a deeply mixed airmass. ...Upper Midwest... Satellite imagery shows some modest drying over far southern MB and western ND associated with a low-amplitude shortwave trough embedded within the northwesterly flow aloft. Modest large-scale ascent attendant to this wave will augment convergence along a surface trough progressing through the region to support thunderstorms during the late afternoon/early evening. Strengthening mid-level northwesterly flow will result in hodographs supportive of potential discrete supercells and large hail production. However, relatively warm profiles (i.e. modest mid-level lapse rates) and lingering convective inhibition should limit overall storm intensity/coverage. Isolated large hail/severe gusts from a few widely spaced supercells seem plausible from late afternoon until around sunset. ...TX Hill Country into South-Central/East Texas... Morning radar and satellite imagery show a well-defined MCV centered over the Concho/McCulloch/Menard county vicinity. This MCV is not expected to move much today as it drifts slowly south/southeastward. However, outflow associated with thunderstorms generated by this MCV is pushing eastward/southeastward into the very moist and buoyant airmass downstream. Primary threat with this system is likely flash flooding (see WPC EROs/MPDs for details), but a few water-loaded downbursts capable of wind damage are possible as the composite outflow pushes into more of south-central/east TX this afternoon and evening. ...Mid-South/Lower Ohio Valley... A pair of convectively enhanced vorticity maxima are apparent across the region on recent radar and satellite imagery. The southernmost vorticity max is currently moving eastward across the central OK/AR border, while the northernmost max is moving through central MO. Both of these features are expected to progress eastward/northeastward today, interacting with the moist and buoyant airmass downstream to promote widespread thunderstorms from the Lower OH Valley into the Mid-South vicinity. Modest but deep southwesterly flow will be in place, which could potentially support some clustering/upscale growth along a northeastward-progressing cold pool, particularly from the MO Bootheel vicinity into western KY and southern IN where the highest storm coverage is expected. Some risk for damaging gusts could accompany this cluster. ...Lower MS Valley... A few water-loaded downbursts are possible within the very moist (i.e. PWAT greater than 2") and strongly buoyant (i.e. MLCAPE over 2500 J/kg) airmass over the region this afternoon. Updraft longevity will be limited by weak shear but new development is likely on any outflow boundaries. ...Florida... A modest mid-level cyclone will drift closer to the Southeast coast today. Mid-level northerly/northwesterly flow around the western periphery of this cyclone is expected across the northern and central FL Peninsula today. Even though it will be relatively modest (i.e. 20 to 25 kt at 500 mb), it should still be enough to foster some long-lived updrafts within the very moist and unstable airmass that is in place. As a result, damaging gusts will be possible within wet microbursts from mid-afternoon to early evening. Read more

SPC Jul 13, 2025 2000 UTC Day 1 Convective Outlook

1 month ago
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0250 PM CDT Sun Jul 13 2025 Valid 132000Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS SOUTHEAST ARIZONA...CENTRAL PENNSYLVANIA INTO NORTHERN NEW YORK... ...SUMMARY... Isolated severe thunderstorms are possible today through early tonight in the Upper Midwest, Mid-Atlantic/Northeast, Southwest, south-central Texas to the Lower Ohio Valley, and Florida. ...20Z Update... Adjustments were made to the general thunderstorm area based on current observations. The forecast is otherwise unchanged. See the previous forecast for additional details. ..Wendt.. 07/13/2025 .PREV DISCUSSION... /ISSUED 1128 AM CDT Sun Jul 13 2025/ ...Northeast/Mid-Atlantic States... Moist low-level convergence, orographic effects, and glancing ascent from an exiting shortwave trough will combine to support widespread thunderstorm development from western/central NY southward into central VA today. Shear is weak across much of the region, with a generally disorganized multicellular mode anticipated. As such, water-loaded downbursts will be the primary risk. However, modestly stronger mid-level southwesterlies could support some sustained multicells from central/northern NY into central PA. Consequently, there is corridor of greater severe potential across this region where storm clustering and linear segments appear more likely. ...Southwest... Modest northerly flow aloft is forecast across northern NM, turning more northeasterly over southeast AZ. Widespread storms are expected to develop off the higher terrain and then progress southward/southwestward from mid-afternoon to mid-evening. Given moderate northeasterly flow, the potential for strong gusts exists, particularly across southeast AZ, where high-based storms coming off the higher terrain will move into a deeply mixed airmass. ...Upper Midwest... Satellite imagery shows some modest drying over far southern MB and western ND associated with a low-amplitude shortwave trough embedded within the northwesterly flow aloft. Modest large-scale ascent attendant to this wave will augment convergence along a surface trough progressing through the region to support thunderstorms during the late afternoon/early evening. Strengthening mid-level northwesterly flow will result in hodographs supportive of potential discrete supercells and large hail production. However, relatively warm profiles (i.e. modest mid-level lapse rates) and lingering convective inhibition should limit overall storm intensity/coverage. Isolated large hail/severe gusts from a few widely spaced supercells seem plausible from late afternoon until around sunset. ...TX Hill Country into South-Central/East Texas... Morning radar and satellite imagery show a well-defined MCV centered over the Concho/McCulloch/Menard county vicinity. This MCV is not expected to move much today as it drifts slowly south/southeastward. However, outflow associated with thunderstorms generated by this MCV is pushing eastward/southeastward into the very moist and buoyant airmass downstream. Primary threat with this system is likely flash flooding (see WPC EROs/MPDs for details), but a few water-loaded downbursts capable of wind damage are possible as the composite outflow pushes into more of south-central/east TX this afternoon and evening. ...Mid-South/Lower Ohio Valley... A pair of convectively enhanced vorticity maxima are apparent across the region on recent radar and satellite imagery. The southernmost vorticity max is currently moving eastward across the central OK/AR border, while the northernmost max is moving through central MO. Both of these features are expected to progress eastward/northeastward today, interacting with the moist and buoyant airmass downstream to promote widespread thunderstorms from the Lower OH Valley into the Mid-South vicinity. Modest but deep southwesterly flow will be in place, which could potentially support some clustering/upscale growth along a northeastward-progressing cold pool, particularly from the MO Bootheel vicinity into western KY and southern IN where the highest storm coverage is expected. Some risk for damaging gusts could accompany this cluster. ...Lower MS Valley... A few water-loaded downbursts are possible within the very moist (i.e. PWAT greater than 2") and strongly buoyant (i.e. MLCAPE over 2500 J/kg) airmass over the region this afternoon. Updraft longevity will be limited by weak shear but new development is likely on any outflow boundaries. ...Florida... A modest mid-level cyclone will drift closer to the Southeast coast today. Mid-level northerly/northwesterly flow around the western periphery of this cyclone is expected across the northern and central FL Peninsula today. Even though it will be relatively modest (i.e. 20 to 25 kt at 500 mb), it should still be enough to foster some long-lived updrafts within the very moist and unstable airmass that is in place. As a result, damaging gusts will be possible within wet microbursts from mid-afternoon to early evening. Read more

SPC Jul 13, 2025 2000 UTC Day 1 Convective Outlook

1 month ago
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0250 PM CDT Sun Jul 13 2025 Valid 132000Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS SOUTHEAST ARIZONA...CENTRAL PENNSYLVANIA INTO NORTHERN NEW YORK... ...SUMMARY... Isolated severe thunderstorms are possible today through early tonight in the Upper Midwest, Mid-Atlantic/Northeast, Southwest, south-central Texas to the Lower Ohio Valley, and Florida. ...20Z Update... Adjustments were made to the general thunderstorm area based on current observations. The forecast is otherwise unchanged. See the previous forecast for additional details. ..Wendt.. 07/13/2025 .PREV DISCUSSION... /ISSUED 1128 AM CDT Sun Jul 13 2025/ ...Northeast/Mid-Atlantic States... Moist low-level convergence, orographic effects, and glancing ascent from an exiting shortwave trough will combine to support widespread thunderstorm development from western/central NY southward into central VA today. Shear is weak across much of the region, with a generally disorganized multicellular mode anticipated. As such, water-loaded downbursts will be the primary risk. However, modestly stronger mid-level southwesterlies could support some sustained multicells from central/northern NY into central PA. Consequently, there is corridor of greater severe potential across this region where storm clustering and linear segments appear more likely. ...Southwest... Modest northerly flow aloft is forecast across northern NM, turning more northeasterly over southeast AZ. Widespread storms are expected to develop off the higher terrain and then progress southward/southwestward from mid-afternoon to mid-evening. Given moderate northeasterly flow, the potential for strong gusts exists, particularly across southeast AZ, where high-based storms coming off the higher terrain will move into a deeply mixed airmass. ...Upper Midwest... Satellite imagery shows some modest drying over far southern MB and western ND associated with a low-amplitude shortwave trough embedded within the northwesterly flow aloft. Modest large-scale ascent attendant to this wave will augment convergence along a surface trough progressing through the region to support thunderstorms during the late afternoon/early evening. Strengthening mid-level northwesterly flow will result in hodographs supportive of potential discrete supercells and large hail production. However, relatively warm profiles (i.e. modest mid-level lapse rates) and lingering convective inhibition should limit overall storm intensity/coverage. Isolated large hail/severe gusts from a few widely spaced supercells seem plausible from late afternoon until around sunset. ...TX Hill Country into South-Central/East Texas... Morning radar and satellite imagery show a well-defined MCV centered over the Concho/McCulloch/Menard county vicinity. This MCV is not expected to move much today as it drifts slowly south/southeastward. However, outflow associated with thunderstorms generated by this MCV is pushing eastward/southeastward into the very moist and buoyant airmass downstream. Primary threat with this system is likely flash flooding (see WPC EROs/MPDs for details), but a few water-loaded downbursts capable of wind damage are possible as the composite outflow pushes into more of south-central/east TX this afternoon and evening. ...Mid-South/Lower Ohio Valley... A pair of convectively enhanced vorticity maxima are apparent across the region on recent radar and satellite imagery. The southernmost vorticity max is currently moving eastward across the central OK/AR border, while the northernmost max is moving through central MO. Both of these features are expected to progress eastward/northeastward today, interacting with the moist and buoyant airmass downstream to promote widespread thunderstorms from the Lower OH Valley into the Mid-South vicinity. Modest but deep southwesterly flow will be in place, which could potentially support some clustering/upscale growth along a northeastward-progressing cold pool, particularly from the MO Bootheel vicinity into western KY and southern IN where the highest storm coverage is expected. Some risk for damaging gusts could accompany this cluster. ...Lower MS Valley... A few water-loaded downbursts are possible within the very moist (i.e. PWAT greater than 2") and strongly buoyant (i.e. MLCAPE over 2500 J/kg) airmass over the region this afternoon. Updraft longevity will be limited by weak shear but new development is likely on any outflow boundaries. ...Florida... A modest mid-level cyclone will drift closer to the Southeast coast today. Mid-level northerly/northwesterly flow around the western periphery of this cyclone is expected across the northern and central FL Peninsula today. Even though it will be relatively modest (i.e. 20 to 25 kt at 500 mb), it should still be enough to foster some long-lived updrafts within the very moist and unstable airmass that is in place. As a result, damaging gusts will be possible within wet microbursts from mid-afternoon to early evening. Read more

SPC Jul 13, 2025 2000 UTC Day 1 Convective Outlook

1 month ago
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0250 PM CDT Sun Jul 13 2025 Valid 132000Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS SOUTHEAST ARIZONA...CENTRAL PENNSYLVANIA INTO NORTHERN NEW YORK... ...SUMMARY... Isolated severe thunderstorms are possible today through early tonight in the Upper Midwest, Mid-Atlantic/Northeast, Southwest, south-central Texas to the Lower Ohio Valley, and Florida. ...20Z Update... Adjustments were made to the general thunderstorm area based on current observations. The forecast is otherwise unchanged. See the previous forecast for additional details. ..Wendt.. 07/13/2025 .PREV DISCUSSION... /ISSUED 1128 AM CDT Sun Jul 13 2025/ ...Northeast/Mid-Atlantic States... Moist low-level convergence, orographic effects, and glancing ascent from an exiting shortwave trough will combine to support widespread thunderstorm development from western/central NY southward into central VA today. Shear is weak across much of the region, with a generally disorganized multicellular mode anticipated. As such, water-loaded downbursts will be the primary risk. However, modestly stronger mid-level southwesterlies could support some sustained multicells from central/northern NY into central PA. Consequently, there is corridor of greater severe potential across this region where storm clustering and linear segments appear more likely. ...Southwest... Modest northerly flow aloft is forecast across northern NM, turning more northeasterly over southeast AZ. Widespread storms are expected to develop off the higher terrain and then progress southward/southwestward from mid-afternoon to mid-evening. Given moderate northeasterly flow, the potential for strong gusts exists, particularly across southeast AZ, where high-based storms coming off the higher terrain will move into a deeply mixed airmass. ...Upper Midwest... Satellite imagery shows some modest drying over far southern MB and western ND associated with a low-amplitude shortwave trough embedded within the northwesterly flow aloft. Modest large-scale ascent attendant to this wave will augment convergence along a surface trough progressing through the region to support thunderstorms during the late afternoon/early evening. Strengthening mid-level northwesterly flow will result in hodographs supportive of potential discrete supercells and large hail production. However, relatively warm profiles (i.e. modest mid-level lapse rates) and lingering convective inhibition should limit overall storm intensity/coverage. Isolated large hail/severe gusts from a few widely spaced supercells seem plausible from late afternoon until around sunset. ...TX Hill Country into South-Central/East Texas... Morning radar and satellite imagery show a well-defined MCV centered over the Concho/McCulloch/Menard county vicinity. This MCV is not expected to move much today as it drifts slowly south/southeastward. However, outflow associated with thunderstorms generated by this MCV is pushing eastward/southeastward into the very moist and buoyant airmass downstream. Primary threat with this system is likely flash flooding (see WPC EROs/MPDs for details), but a few water-loaded downbursts capable of wind damage are possible as the composite outflow pushes into more of south-central/east TX this afternoon and evening. ...Mid-South/Lower Ohio Valley... A pair of convectively enhanced vorticity maxima are apparent across the region on recent radar and satellite imagery. The southernmost vorticity max is currently moving eastward across the central OK/AR border, while the northernmost max is moving through central MO. Both of these features are expected to progress eastward/northeastward today, interacting with the moist and buoyant airmass downstream to promote widespread thunderstorms from the Lower OH Valley into the Mid-South vicinity. Modest but deep southwesterly flow will be in place, which could potentially support some clustering/upscale growth along a northeastward-progressing cold pool, particularly from the MO Bootheel vicinity into western KY and southern IN where the highest storm coverage is expected. Some risk for damaging gusts could accompany this cluster. ...Lower MS Valley... A few water-loaded downbursts are possible within the very moist (i.e. PWAT greater than 2") and strongly buoyant (i.e. MLCAPE over 2500 J/kg) airmass over the region this afternoon. Updraft longevity will be limited by weak shear but new development is likely on any outflow boundaries. ...Florida... A modest mid-level cyclone will drift closer to the Southeast coast today. Mid-level northerly/northwesterly flow around the western periphery of this cyclone is expected across the northern and central FL Peninsula today. Even though it will be relatively modest (i.e. 20 to 25 kt at 500 mb), it should still be enough to foster some long-lived updrafts within the very moist and unstable airmass that is in place. As a result, damaging gusts will be possible within wet microbursts from mid-afternoon to early evening. Read more

SPC Jul 13, 2025 1930 UTC Day 3 Severe Thunderstorm Outlook

1 month ago
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 0239 PM CDT Sun Jul 13 2025 Valid 151200Z - 161200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE UPPER MIDWEST TO THE CENTRAL HIGH PLAINS AND ACROSS THE MID MISSISSIPPI VALLEY... CORRECTED FOR NDFD FILL ERROR ...SUMMARY... Isolated strong to severe thunderstorms are possible Tuesday afternoon and evening across portions of the central Plains to Upper Midwest and Mid Mississippi Valley. ...Northern/Central Plains to the Upper Midwest... A broad upper trough and multiple convectively enhanced shortwave perturbations moving out of southern Canada should move east/southeastward over the Northern Rockies Tuesday. A belt of enhanced mid-level flow (30-40 kt) will also spread eastward, overlapping with a sagging cold front from the western Great Lakes, across the northern Plains and into the Rockies. Along and south of the front, rich low-level moisture is expected with dewpoints in the upper 60s to low 70s F contributing to 2500-3000 J/kg of MLCAPE. Ascent from the approach trough and flow aloft will aid in deepening a lee low across the central High Plains at the junction of the front and a prominent lee trough. Convergence along these features, should support scattered thunderstorms Tuesday afternoon and evening. With deep-layer shear increasing to 30-35 kt, scattered thunderstorms organized into multicell clusters or supercell structures is possible along the cold front from the eastern Dakotas to the western Great Lakes and within the broader warm sector across southern SD to central NE. More isolated storms will also be possible along and east of the lee trough trailing the surface low to the south. Steep low mid-level lapse rates of 8+ C/km will be more than sufficient for isolated severe storms capable of damaging gusts and some hail. Consideration was given to higher severe probabilities given large forecast buoyancy and more focused forcing along the front/triple point. However, variability in the timing of the front and overnight convective influences at this range lend low confidence to any one solution. At least an isolated severe risk should also extend westward within the post-front upslope regime across far southern MT and into eastern WY and western SD. While buoyancy will be reduced, low-level moist advection and upslope flow behind the front will support isolated to widely scattered storms within enhanced mid-level flow. Hail and isolated damaging gusts are possible. ...Mid MS Valley... Multiple model solutions show a rather well-defined MCV moving out of the southern Plains and Ozarks into the mid MS Valley by Tuesday morning. A very warm and humid air mass will remain in place ahead of this feature supporting sufficient buoyancy for scattered thunderstorms. The exact placement and intensity of this feature remains very uncertain owing to different mesoscale solutions/convective influence in the coming days. Still, some enhancement of the low/mid-level flow field could support some organized clusters capable of damaging gusts. ..Lyons.. 07/13/2025 Read more

SPC Jul 13, 2025 1930 UTC Day 3 Severe Thunderstorm Outlook

1 month ago
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 0239 PM CDT Sun Jul 13 2025 Valid 151200Z - 161200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE UPPER MIDWEST TO THE CENTRAL HIGH PLAINS AND ACROSS THE MID MISSISSIPPI VALLEY... CORRECTED FOR NDFD FILL ERROR ...SUMMARY... Isolated strong to severe thunderstorms are possible Tuesday afternoon and evening across portions of the central Plains to Upper Midwest and Mid Mississippi Valley. ...Northern/Central Plains to the Upper Midwest... A broad upper trough and multiple convectively enhanced shortwave perturbations moving out of southern Canada should move east/southeastward over the Northern Rockies Tuesday. A belt of enhanced mid-level flow (30-40 kt) will also spread eastward, overlapping with a sagging cold front from the western Great Lakes, across the northern Plains and into the Rockies. Along and south of the front, rich low-level moisture is expected with dewpoints in the upper 60s to low 70s F contributing to 2500-3000 J/kg of MLCAPE. Ascent from the approach trough and flow aloft will aid in deepening a lee low across the central High Plains at the junction of the front and a prominent lee trough. Convergence along these features, should support scattered thunderstorms Tuesday afternoon and evening. With deep-layer shear increasing to 30-35 kt, scattered thunderstorms organized into multicell clusters or supercell structures is possible along the cold front from the eastern Dakotas to the western Great Lakes and within the broader warm sector across southern SD to central NE. More isolated storms will also be possible along and east of the lee trough trailing the surface low to the south. Steep low mid-level lapse rates of 8+ C/km will be more than sufficient for isolated severe storms capable of damaging gusts and some hail. Consideration was given to higher severe probabilities given large forecast buoyancy and more focused forcing along the front/triple point. However, variability in the timing of the front and overnight convective influences at this range lend low confidence to any one solution. At least an isolated severe risk should also extend westward within the post-front upslope regime across far southern MT and into eastern WY and western SD. While buoyancy will be reduced, low-level moist advection and upslope flow behind the front will support isolated to widely scattered storms within enhanced mid-level flow. Hail and isolated damaging gusts are possible. ...Mid MS Valley... Multiple model solutions show a rather well-defined MCV moving out of the southern Plains and Ozarks into the mid MS Valley by Tuesday morning. A very warm and humid air mass will remain in place ahead of this feature supporting sufficient buoyancy for scattered thunderstorms. The exact placement and intensity of this feature remains very uncertain owing to different mesoscale solutions/convective influence in the coming days. Still, some enhancement of the low/mid-level flow field could support some organized clusters capable of damaging gusts. ..Lyons.. 07/13/2025 Read more

SPC Jul 13, 2025 1930 UTC Day 3 Severe Thunderstorm Outlook

1 month ago
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 0239 PM CDT Sun Jul 13 2025 Valid 151200Z - 161200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE UPPER MIDWEST TO THE CENTRAL HIGH PLAINS AND ACROSS THE MID MISSISSIPPI VALLEY... CORRECTED FOR NDFD FILL ERROR ...SUMMARY... Isolated strong to severe thunderstorms are possible Tuesday afternoon and evening across portions of the central Plains to Upper Midwest and Mid Mississippi Valley. ...Northern/Central Plains to the Upper Midwest... A broad upper trough and multiple convectively enhanced shortwave perturbations moving out of southern Canada should move east/southeastward over the Northern Rockies Tuesday. A belt of enhanced mid-level flow (30-40 kt) will also spread eastward, overlapping with a sagging cold front from the western Great Lakes, across the northern Plains and into the Rockies. Along and south of the front, rich low-level moisture is expected with dewpoints in the upper 60s to low 70s F contributing to 2500-3000 J/kg of MLCAPE. Ascent from the approach trough and flow aloft will aid in deepening a lee low across the central High Plains at the junction of the front and a prominent lee trough. Convergence along these features, should support scattered thunderstorms Tuesday afternoon and evening. With deep-layer shear increasing to 30-35 kt, scattered thunderstorms organized into multicell clusters or supercell structures is possible along the cold front from the eastern Dakotas to the western Great Lakes and within the broader warm sector across southern SD to central NE. More isolated storms will also be possible along and east of the lee trough trailing the surface low to the south. Steep low mid-level lapse rates of 8+ C/km will be more than sufficient for isolated severe storms capable of damaging gusts and some hail. Consideration was given to higher severe probabilities given large forecast buoyancy and more focused forcing along the front/triple point. However, variability in the timing of the front and overnight convective influences at this range lend low confidence to any one solution. At least an isolated severe risk should also extend westward within the post-front upslope regime across far southern MT and into eastern WY and western SD. While buoyancy will be reduced, low-level moist advection and upslope flow behind the front will support isolated to widely scattered storms within enhanced mid-level flow. Hail and isolated damaging gusts are possible. ...Mid MS Valley... Multiple model solutions show a rather well-defined MCV moving out of the southern Plains and Ozarks into the mid MS Valley by Tuesday morning. A very warm and humid air mass will remain in place ahead of this feature supporting sufficient buoyancy for scattered thunderstorms. The exact placement and intensity of this feature remains very uncertain owing to different mesoscale solutions/convective influence in the coming days. Still, some enhancement of the low/mid-level flow field could support some organized clusters capable of damaging gusts. ..Lyons.. 07/13/2025 Read more

SPC Jul 13, 2025 1930 UTC Day 3 Severe Thunderstorm Outlook

1 month ago
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 0239 PM CDT Sun Jul 13 2025 Valid 151200Z - 161200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE UPPER MIDWEST TO THE CENTRAL HIGH PLAINS AND ACROSS THE MID MISSISSIPPI VALLEY... CORRECTED FOR NDFD FILL ERROR ...SUMMARY... Isolated strong to severe thunderstorms are possible Tuesday afternoon and evening across portions of the central Plains to Upper Midwest and Mid Mississippi Valley. ...Northern/Central Plains to the Upper Midwest... A broad upper trough and multiple convectively enhanced shortwave perturbations moving out of southern Canada should move east/southeastward over the Northern Rockies Tuesday. A belt of enhanced mid-level flow (30-40 kt) will also spread eastward, overlapping with a sagging cold front from the western Great Lakes, across the northern Plains and into the Rockies. Along and south of the front, rich low-level moisture is expected with dewpoints in the upper 60s to low 70s F contributing to 2500-3000 J/kg of MLCAPE. Ascent from the approach trough and flow aloft will aid in deepening a lee low across the central High Plains at the junction of the front and a prominent lee trough. Convergence along these features, should support scattered thunderstorms Tuesday afternoon and evening. With deep-layer shear increasing to 30-35 kt, scattered thunderstorms organized into multicell clusters or supercell structures is possible along the cold front from the eastern Dakotas to the western Great Lakes and within the broader warm sector across southern SD to central NE. More isolated storms will also be possible along and east of the lee trough trailing the surface low to the south. Steep low mid-level lapse rates of 8+ C/km will be more than sufficient for isolated severe storms capable of damaging gusts and some hail. Consideration was given to higher severe probabilities given large forecast buoyancy and more focused forcing along the front/triple point. However, variability in the timing of the front and overnight convective influences at this range lend low confidence to any one solution. At least an isolated severe risk should also extend westward within the post-front upslope regime across far southern MT and into eastern WY and western SD. While buoyancy will be reduced, low-level moist advection and upslope flow behind the front will support isolated to widely scattered storms within enhanced mid-level flow. Hail and isolated damaging gusts are possible. ...Mid MS Valley... Multiple model solutions show a rather well-defined MCV moving out of the southern Plains and Ozarks into the mid MS Valley by Tuesday morning. A very warm and humid air mass will remain in place ahead of this feature supporting sufficient buoyancy for scattered thunderstorms. The exact placement and intensity of this feature remains very uncertain owing to different mesoscale solutions/convective influence in the coming days. Still, some enhancement of the low/mid-level flow field could support some organized clusters capable of damaging gusts. ..Lyons.. 07/13/2025 Read more

SPC Jul 13, 2025 1930 UTC Day 3 Severe Thunderstorm Outlook

1 month ago
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 0239 PM CDT Sun Jul 13 2025 Valid 151200Z - 161200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE UPPER MIDWEST TO THE CENTRAL HIGH PLAINS AND ACROSS THE MID MISSISSIPPI VALLEY... CORRECTED FOR NDFD FILL ERROR ...SUMMARY... Isolated strong to severe thunderstorms are possible Tuesday afternoon and evening across portions of the central Plains to Upper Midwest and Mid Mississippi Valley. ...Northern/Central Plains to the Upper Midwest... A broad upper trough and multiple convectively enhanced shortwave perturbations moving out of southern Canada should move east/southeastward over the Northern Rockies Tuesday. A belt of enhanced mid-level flow (30-40 kt) will also spread eastward, overlapping with a sagging cold front from the western Great Lakes, across the northern Plains and into the Rockies. Along and south of the front, rich low-level moisture is expected with dewpoints in the upper 60s to low 70s F contributing to 2500-3000 J/kg of MLCAPE. Ascent from the approach trough and flow aloft will aid in deepening a lee low across the central High Plains at the junction of the front and a prominent lee trough. Convergence along these features, should support scattered thunderstorms Tuesday afternoon and evening. With deep-layer shear increasing to 30-35 kt, scattered thunderstorms organized into multicell clusters or supercell structures is possible along the cold front from the eastern Dakotas to the western Great Lakes and within the broader warm sector across southern SD to central NE. More isolated storms will also be possible along and east of the lee trough trailing the surface low to the south. Steep low mid-level lapse rates of 8+ C/km will be more than sufficient for isolated severe storms capable of damaging gusts and some hail. Consideration was given to higher severe probabilities given large forecast buoyancy and more focused forcing along the front/triple point. However, variability in the timing of the front and overnight convective influences at this range lend low confidence to any one solution. At least an isolated severe risk should also extend westward within the post-front upslope regime across far southern MT and into eastern WY and western SD. While buoyancy will be reduced, low-level moist advection and upslope flow behind the front will support isolated to widely scattered storms within enhanced mid-level flow. Hail and isolated damaging gusts are possible. ...Mid MS Valley... Multiple model solutions show a rather well-defined MCV moving out of the southern Plains and Ozarks into the mid MS Valley by Tuesday morning. A very warm and humid air mass will remain in place ahead of this feature supporting sufficient buoyancy for scattered thunderstorms. The exact placement and intensity of this feature remains very uncertain owing to different mesoscale solutions/convective influence in the coming days. Still, some enhancement of the low/mid-level flow field could support some organized clusters capable of damaging gusts. ..Lyons.. 07/13/2025 Read more

SPC Jul 13, 2025 1930 UTC Day 3 Severe Thunderstorm Outlook

1 month ago
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 0239 PM CDT Sun Jul 13 2025 Valid 151200Z - 161200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE UPPER MIDWEST TO THE CENTRAL HIGH PLAINS AND ACROSS THE MID MISSISSIPPI VALLEY... CORRECTED FOR NDFD FILL ERROR ...SUMMARY... Isolated strong to severe thunderstorms are possible Tuesday afternoon and evening across portions of the central Plains to Upper Midwest and Mid Mississippi Valley. ...Northern/Central Plains to the Upper Midwest... A broad upper trough and multiple convectively enhanced shortwave perturbations moving out of southern Canada should move east/southeastward over the Northern Rockies Tuesday. A belt of enhanced mid-level flow (30-40 kt) will also spread eastward, overlapping with a sagging cold front from the western Great Lakes, across the northern Plains and into the Rockies. Along and south of the front, rich low-level moisture is expected with dewpoints in the upper 60s to low 70s F contributing to 2500-3000 J/kg of MLCAPE. Ascent from the approach trough and flow aloft will aid in deepening a lee low across the central High Plains at the junction of the front and a prominent lee trough. Convergence along these features, should support scattered thunderstorms Tuesday afternoon and evening. With deep-layer shear increasing to 30-35 kt, scattered thunderstorms organized into multicell clusters or supercell structures is possible along the cold front from the eastern Dakotas to the western Great Lakes and within the broader warm sector across southern SD to central NE. More isolated storms will also be possible along and east of the lee trough trailing the surface low to the south. Steep low mid-level lapse rates of 8+ C/km will be more than sufficient for isolated severe storms capable of damaging gusts and some hail. Consideration was given to higher severe probabilities given large forecast buoyancy and more focused forcing along the front/triple point. However, variability in the timing of the front and overnight convective influences at this range lend low confidence to any one solution. At least an isolated severe risk should also extend westward within the post-front upslope regime across far southern MT and into eastern WY and western SD. While buoyancy will be reduced, low-level moist advection and upslope flow behind the front will support isolated to widely scattered storms within enhanced mid-level flow. Hail and isolated damaging gusts are possible. ...Mid MS Valley... Multiple model solutions show a rather well-defined MCV moving out of the southern Plains and Ozarks into the mid MS Valley by Tuesday morning. A very warm and humid air mass will remain in place ahead of this feature supporting sufficient buoyancy for scattered thunderstorms. The exact placement and intensity of this feature remains very uncertain owing to different mesoscale solutions/convective influence in the coming days. Still, some enhancement of the low/mid-level flow field could support some organized clusters capable of damaging gusts. ..Lyons.. 07/13/2025 Read more

SPC Jul 13, 2025 1930 UTC Day 3 Severe Thunderstorm Outlook

1 month ago
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 0239 PM CDT Sun Jul 13 2025 Valid 151200Z - 161200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE UPPER MIDWEST TO THE CENTRAL HIGH PLAINS AND ACROSS THE MID MISSISSIPPI VALLEY... CORRECTED FOR NDFD FILL ERROR ...SUMMARY... Isolated strong to severe thunderstorms are possible Tuesday afternoon and evening across portions of the central Plains to Upper Midwest and Mid Mississippi Valley. ...Northern/Central Plains to the Upper Midwest... A broad upper trough and multiple convectively enhanced shortwave perturbations moving out of southern Canada should move east/southeastward over the Northern Rockies Tuesday. A belt of enhanced mid-level flow (30-40 kt) will also spread eastward, overlapping with a sagging cold front from the western Great Lakes, across the northern Plains and into the Rockies. Along and south of the front, rich low-level moisture is expected with dewpoints in the upper 60s to low 70s F contributing to 2500-3000 J/kg of MLCAPE. Ascent from the approach trough and flow aloft will aid in deepening a lee low across the central High Plains at the junction of the front and a prominent lee trough. Convergence along these features, should support scattered thunderstorms Tuesday afternoon and evening. With deep-layer shear increasing to 30-35 kt, scattered thunderstorms organized into multicell clusters or supercell structures is possible along the cold front from the eastern Dakotas to the western Great Lakes and within the broader warm sector across southern SD to central NE. More isolated storms will also be possible along and east of the lee trough trailing the surface low to the south. Steep low mid-level lapse rates of 8+ C/km will be more than sufficient for isolated severe storms capable of damaging gusts and some hail. Consideration was given to higher severe probabilities given large forecast buoyancy and more focused forcing along the front/triple point. However, variability in the timing of the front and overnight convective influences at this range lend low confidence to any one solution. At least an isolated severe risk should also extend westward within the post-front upslope regime across far southern MT and into eastern WY and western SD. While buoyancy will be reduced, low-level moist advection and upslope flow behind the front will support isolated to widely scattered storms within enhanced mid-level flow. Hail and isolated damaging gusts are possible. ...Mid MS Valley... Multiple model solutions show a rather well-defined MCV moving out of the southern Plains and Ozarks into the mid MS Valley by Tuesday morning. A very warm and humid air mass will remain in place ahead of this feature supporting sufficient buoyancy for scattered thunderstorms. The exact placement and intensity of this feature remains very uncertain owing to different mesoscale solutions/convective influence in the coming days. Still, some enhancement of the low/mid-level flow field could support some organized clusters capable of damaging gusts. ..Lyons.. 07/13/2025 Read more

SPC Jul 13, 2025 1930 UTC Day 3 Severe Thunderstorm Outlook

1 month ago
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 0239 PM CDT Sun Jul 13 2025 Valid 151200Z - 161200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE UPPER MIDWEST TO THE CENTRAL HIGH PLAINS AND ACROSS THE MID MISSISSIPPI VALLEY... CORRECTED FOR NDFD FILL ERROR ...SUMMARY... Isolated strong to severe thunderstorms are possible Tuesday afternoon and evening across portions of the central Plains to Upper Midwest and Mid Mississippi Valley. ...Northern/Central Plains to the Upper Midwest... A broad upper trough and multiple convectively enhanced shortwave perturbations moving out of southern Canada should move east/southeastward over the Northern Rockies Tuesday. A belt of enhanced mid-level flow (30-40 kt) will also spread eastward, overlapping with a sagging cold front from the western Great Lakes, across the northern Plains and into the Rockies. Along and south of the front, rich low-level moisture is expected with dewpoints in the upper 60s to low 70s F contributing to 2500-3000 J/kg of MLCAPE. Ascent from the approach trough and flow aloft will aid in deepening a lee low across the central High Plains at the junction of the front and a prominent lee trough. Convergence along these features, should support scattered thunderstorms Tuesday afternoon and evening. With deep-layer shear increasing to 30-35 kt, scattered thunderstorms organized into multicell clusters or supercell structures is possible along the cold front from the eastern Dakotas to the western Great Lakes and within the broader warm sector across southern SD to central NE. More isolated storms will also be possible along and east of the lee trough trailing the surface low to the south. Steep low mid-level lapse rates of 8+ C/km will be more than sufficient for isolated severe storms capable of damaging gusts and some hail. Consideration was given to higher severe probabilities given large forecast buoyancy and more focused forcing along the front/triple point. However, variability in the timing of the front and overnight convective influences at this range lend low confidence to any one solution. At least an isolated severe risk should also extend westward within the post-front upslope regime across far southern MT and into eastern WY and western SD. While buoyancy will be reduced, low-level moist advection and upslope flow behind the front will support isolated to widely scattered storms within enhanced mid-level flow. Hail and isolated damaging gusts are possible. ...Mid MS Valley... Multiple model solutions show a rather well-defined MCV moving out of the southern Plains and Ozarks into the mid MS Valley by Tuesday morning. A very warm and humid air mass will remain in place ahead of this feature supporting sufficient buoyancy for scattered thunderstorms. The exact placement and intensity of this feature remains very uncertain owing to different mesoscale solutions/convective influence in the coming days. Still, some enhancement of the low/mid-level flow field could support some organized clusters capable of damaging gusts. ..Lyons.. 07/13/2025 Read more

SPC Jul 13, 2025 1930 UTC Day 3 Severe Thunderstorm Outlook

1 month ago
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 0239 PM CDT Sun Jul 13 2025 Valid 151200Z - 161200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE UPPER MIDWEST TO THE CENTRAL HIGH PLAINS AND ACROSS THE MID MISSISSIPPI VALLEY... CORRECTED FOR NDFD FILL ERROR ...SUMMARY... Isolated strong to severe thunderstorms are possible Tuesday afternoon and evening across portions of the central Plains to Upper Midwest and Mid Mississippi Valley. ...Northern/Central Plains to the Upper Midwest... A broad upper trough and multiple convectively enhanced shortwave perturbations moving out of southern Canada should move east/southeastward over the Northern Rockies Tuesday. A belt of enhanced mid-level flow (30-40 kt) will also spread eastward, overlapping with a sagging cold front from the western Great Lakes, across the northern Plains and into the Rockies. Along and south of the front, rich low-level moisture is expected with dewpoints in the upper 60s to low 70s F contributing to 2500-3000 J/kg of MLCAPE. Ascent from the approach trough and flow aloft will aid in deepening a lee low across the central High Plains at the junction of the front and a prominent lee trough. Convergence along these features, should support scattered thunderstorms Tuesday afternoon and evening. With deep-layer shear increasing to 30-35 kt, scattered thunderstorms organized into multicell clusters or supercell structures is possible along the cold front from the eastern Dakotas to the western Great Lakes and within the broader warm sector across southern SD to central NE. More isolated storms will also be possible along and east of the lee trough trailing the surface low to the south. Steep low mid-level lapse rates of 8+ C/km will be more than sufficient for isolated severe storms capable of damaging gusts and some hail. Consideration was given to higher severe probabilities given large forecast buoyancy and more focused forcing along the front/triple point. However, variability in the timing of the front and overnight convective influences at this range lend low confidence to any one solution. At least an isolated severe risk should also extend westward within the post-front upslope regime across far southern MT and into eastern WY and western SD. While buoyancy will be reduced, low-level moist advection and upslope flow behind the front will support isolated to widely scattered storms within enhanced mid-level flow. Hail and isolated damaging gusts are possible. ...Mid MS Valley... Multiple model solutions show a rather well-defined MCV moving out of the southern Plains and Ozarks into the mid MS Valley by Tuesday morning. A very warm and humid air mass will remain in place ahead of this feature supporting sufficient buoyancy for scattered thunderstorms. The exact placement and intensity of this feature remains very uncertain owing to different mesoscale solutions/convective influence in the coming days. Still, some enhancement of the low/mid-level flow field could support some organized clusters capable of damaging gusts. ..Lyons.. 07/13/2025 Read more

SPC Jul 13, 2025 1930 UTC Day 3 Severe Thunderstorm Outlook

1 month ago
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 0239 PM CDT Sun Jul 13 2025 Valid 151200Z - 161200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE UPPER MIDWEST TO THE CENTRAL HIGH PLAINS AND ACROSS THE MID MISSISSIPPI VALLEY... CORRECTED FOR NDFD FILL ERROR ...SUMMARY... Isolated strong to severe thunderstorms are possible Tuesday afternoon and evening across portions of the central Plains to Upper Midwest and Mid Mississippi Valley. ...Northern/Central Plains to the Upper Midwest... A broad upper trough and multiple convectively enhanced shortwave perturbations moving out of southern Canada should move east/southeastward over the Northern Rockies Tuesday. A belt of enhanced mid-level flow (30-40 kt) will also spread eastward, overlapping with a sagging cold front from the western Great Lakes, across the northern Plains and into the Rockies. Along and south of the front, rich low-level moisture is expected with dewpoints in the upper 60s to low 70s F contributing to 2500-3000 J/kg of MLCAPE. Ascent from the approach trough and flow aloft will aid in deepening a lee low across the central High Plains at the junction of the front and a prominent lee trough. Convergence along these features, should support scattered thunderstorms Tuesday afternoon and evening. With deep-layer shear increasing to 30-35 kt, scattered thunderstorms organized into multicell clusters or supercell structures is possible along the cold front from the eastern Dakotas to the western Great Lakes and within the broader warm sector across southern SD to central NE. More isolated storms will also be possible along and east of the lee trough trailing the surface low to the south. Steep low mid-level lapse rates of 8+ C/km will be more than sufficient for isolated severe storms capable of damaging gusts and some hail. Consideration was given to higher severe probabilities given large forecast buoyancy and more focused forcing along the front/triple point. However, variability in the timing of the front and overnight convective influences at this range lend low confidence to any one solution. At least an isolated severe risk should also extend westward within the post-front upslope regime across far southern MT and into eastern WY and western SD. While buoyancy will be reduced, low-level moist advection and upslope flow behind the front will support isolated to widely scattered storms within enhanced mid-level flow. Hail and isolated damaging gusts are possible. ...Mid MS Valley... Multiple model solutions show a rather well-defined MCV moving out of the southern Plains and Ozarks into the mid MS Valley by Tuesday morning. A very warm and humid air mass will remain in place ahead of this feature supporting sufficient buoyancy for scattered thunderstorms. The exact placement and intensity of this feature remains very uncertain owing to different mesoscale solutions/convective influence in the coming days. Still, some enhancement of the low/mid-level flow field could support some organized clusters capable of damaging gusts. ..Lyons.. 07/13/2025 Read more

SPC Jul 13, 2025 1930 UTC Day 3 Severe Thunderstorm Outlook

1 month ago
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 0239 PM CDT Sun Jul 13 2025 Valid 151200Z - 161200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE UPPER MIDWEST TO THE CENTRAL HIGH PLAINS AND ACROSS THE MID MISSISSIPPI VALLEY... CORRECTED FOR NDFD FILL ERROR ...SUMMARY... Isolated strong to severe thunderstorms are possible Tuesday afternoon and evening across portions of the central Plains to Upper Midwest and Mid Mississippi Valley. ...Northern/Central Plains to the Upper Midwest... A broad upper trough and multiple convectively enhanced shortwave perturbations moving out of southern Canada should move east/southeastward over the Northern Rockies Tuesday. A belt of enhanced mid-level flow (30-40 kt) will also spread eastward, overlapping with a sagging cold front from the western Great Lakes, across the northern Plains and into the Rockies. Along and south of the front, rich low-level moisture is expected with dewpoints in the upper 60s to low 70s F contributing to 2500-3000 J/kg of MLCAPE. Ascent from the approach trough and flow aloft will aid in deepening a lee low across the central High Plains at the junction of the front and a prominent lee trough. Convergence along these features, should support scattered thunderstorms Tuesday afternoon and evening. With deep-layer shear increasing to 30-35 kt, scattered thunderstorms organized into multicell clusters or supercell structures is possible along the cold front from the eastern Dakotas to the western Great Lakes and within the broader warm sector across southern SD to central NE. More isolated storms will also be possible along and east of the lee trough trailing the surface low to the south. Steep low mid-level lapse rates of 8+ C/km will be more than sufficient for isolated severe storms capable of damaging gusts and some hail. Consideration was given to higher severe probabilities given large forecast buoyancy and more focused forcing along the front/triple point. However, variability in the timing of the front and overnight convective influences at this range lend low confidence to any one solution. At least an isolated severe risk should also extend westward within the post-front upslope regime across far southern MT and into eastern WY and western SD. While buoyancy will be reduced, low-level moist advection and upslope flow behind the front will support isolated to widely scattered storms within enhanced mid-level flow. Hail and isolated damaging gusts are possible. ...Mid MS Valley... Multiple model solutions show a rather well-defined MCV moving out of the southern Plains and Ozarks into the mid MS Valley by Tuesday morning. A very warm and humid air mass will remain in place ahead of this feature supporting sufficient buoyancy for scattered thunderstorms. The exact placement and intensity of this feature remains very uncertain owing to different mesoscale solutions/convective influence in the coming days. Still, some enhancement of the low/mid-level flow field could support some organized clusters capable of damaging gusts. ..Lyons.. 07/13/2025 Read more

SPC Jul 13, 2025 1930 UTC Day 3 Severe Thunderstorm Outlook

1 month ago
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 0239 PM CDT Sun Jul 13 2025 Valid 151200Z - 161200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE UPPER MIDWEST TO THE CENTRAL HIGH PLAINS AND ACROSS THE MID MISSISSIPPI VALLEY... CORRECTED FOR NDFD FILL ERROR ...SUMMARY... Isolated strong to severe thunderstorms are possible Tuesday afternoon and evening across portions of the central Plains to Upper Midwest and Mid Mississippi Valley. ...Northern/Central Plains to the Upper Midwest... A broad upper trough and multiple convectively enhanced shortwave perturbations moving out of southern Canada should move east/southeastward over the Northern Rockies Tuesday. A belt of enhanced mid-level flow (30-40 kt) will also spread eastward, overlapping with a sagging cold front from the western Great Lakes, across the northern Plains and into the Rockies. Along and south of the front, rich low-level moisture is expected with dewpoints in the upper 60s to low 70s F contributing to 2500-3000 J/kg of MLCAPE. Ascent from the approach trough and flow aloft will aid in deepening a lee low across the central High Plains at the junction of the front and a prominent lee trough. Convergence along these features, should support scattered thunderstorms Tuesday afternoon and evening. With deep-layer shear increasing to 30-35 kt, scattered thunderstorms organized into multicell clusters or supercell structures is possible along the cold front from the eastern Dakotas to the western Great Lakes and within the broader warm sector across southern SD to central NE. More isolated storms will also be possible along and east of the lee trough trailing the surface low to the south. Steep low mid-level lapse rates of 8+ C/km will be more than sufficient for isolated severe storms capable of damaging gusts and some hail. Consideration was given to higher severe probabilities given large forecast buoyancy and more focused forcing along the front/triple point. However, variability in the timing of the front and overnight convective influences at this range lend low confidence to any one solution. At least an isolated severe risk should also extend westward within the post-front upslope regime across far southern MT and into eastern WY and western SD. While buoyancy will be reduced, low-level moist advection and upslope flow behind the front will support isolated to widely scattered storms within enhanced mid-level flow. Hail and isolated damaging gusts are possible. ...Mid MS Valley... Multiple model solutions show a rather well-defined MCV moving out of the southern Plains and Ozarks into the mid MS Valley by Tuesday morning. A very warm and humid air mass will remain in place ahead of this feature supporting sufficient buoyancy for scattered thunderstorms. The exact placement and intensity of this feature remains very uncertain owing to different mesoscale solutions/convective influence in the coming days. Still, some enhancement of the low/mid-level flow field could support some organized clusters capable of damaging gusts. ..Lyons.. 07/13/2025 Read more

SPC Jul 13, 2025 1930 UTC Day 3 Severe Thunderstorm Outlook

1 month ago
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 0239 PM CDT Sun Jul 13 2025 Valid 151200Z - 161200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE UPPER MIDWEST TO THE CENTRAL HIGH PLAINS AND ACROSS THE MID MISSISSIPPI VALLEY... CORRECTED FOR NDFD FILL ERROR ...SUMMARY... Isolated strong to severe thunderstorms are possible Tuesday afternoon and evening across portions of the central Plains to Upper Midwest and Mid Mississippi Valley. ...Northern/Central Plains to the Upper Midwest... A broad upper trough and multiple convectively enhanced shortwave perturbations moving out of southern Canada should move east/southeastward over the Northern Rockies Tuesday. A belt of enhanced mid-level flow (30-40 kt) will also spread eastward, overlapping with a sagging cold front from the western Great Lakes, across the northern Plains and into the Rockies. Along and south of the front, rich low-level moisture is expected with dewpoints in the upper 60s to low 70s F contributing to 2500-3000 J/kg of MLCAPE. Ascent from the approach trough and flow aloft will aid in deepening a lee low across the central High Plains at the junction of the front and a prominent lee trough. Convergence along these features, should support scattered thunderstorms Tuesday afternoon and evening. With deep-layer shear increasing to 30-35 kt, scattered thunderstorms organized into multicell clusters or supercell structures is possible along the cold front from the eastern Dakotas to the western Great Lakes and within the broader warm sector across southern SD to central NE. More isolated storms will also be possible along and east of the lee trough trailing the surface low to the south. Steep low mid-level lapse rates of 8+ C/km will be more than sufficient for isolated severe storms capable of damaging gusts and some hail. Consideration was given to higher severe probabilities given large forecast buoyancy and more focused forcing along the front/triple point. However, variability in the timing of the front and overnight convective influences at this range lend low confidence to any one solution. At least an isolated severe risk should also extend westward within the post-front upslope regime across far southern MT and into eastern WY and western SD. While buoyancy will be reduced, low-level moist advection and upslope flow behind the front will support isolated to widely scattered storms within enhanced mid-level flow. Hail and isolated damaging gusts are possible. ...Mid MS Valley... Multiple model solutions show a rather well-defined MCV moving out of the southern Plains and Ozarks into the mid MS Valley by Tuesday morning. A very warm and humid air mass will remain in place ahead of this feature supporting sufficient buoyancy for scattered thunderstorms. The exact placement and intensity of this feature remains very uncertain owing to different mesoscale solutions/convective influence in the coming days. Still, some enhancement of the low/mid-level flow field could support some organized clusters capable of damaging gusts. ..Lyons.. 07/13/2025 Read more

SPC MD 1659

1 month ago
MD 1659 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR CENTRAL PA INTO PARTS OF NY AND EXTREME NORTHWEST VT
Mesoscale Discussion 1659 NWS Storm Prediction Center Norman OK 1223 PM CDT Sun Jul 13 2025 Areas affected...Central PA into parts of NY and extreme northwest VT Concerning...Severe potential...Watch possible Valid 131723Z - 132000Z Probability of Watch Issuance...40 percent SUMMARY...Storms capable of producing localized wind damage are possible this afternoon. DISCUSSION...Morning soundings from KALB and KBUF depicted very rich moisture, with PWs in the 1.8 - 2 inch range. Midlevel lapse rates are weak, but strong heating of this very moist airmass will result in MLCAPE increasing into the 1500-2500 J/kg range this afternoon. Scattered to numerous thunderstorms are expected to develop with time within the minimally capped environment. Generally weak effective shear (15-20 kt across PA/southern NY and 20-25 kt across northern NY) will tend to limit storm organization. However, steepening low-level lapse rates and large PW will support a threat of isolated wet microbursts and small outflow-dominant clusters capable of producing localized wind damage, especially where stronger pre-convective heating occurs. The need for a watch is uncertain due to the anticipated lack of storm organization, but watch issuance will become increasingly possible if observational trends begin to support areas of more concentrated wind-damage potential. ..Dean/Mosier.. 07/13/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...BTV...ALY...BGM...BUF...CTP...PBZ... LAT...LON 43007429 40867699 39777744 39787832 39827896 40907914 41647932 42247918 42527870 42687845 43067773 43437624 44627554 44827545 45057454 44987296 44547318 43007429 MOST PROBABLE PEAK WIND GUST...55-70 MPH Read more

SPC Jul 13, 2025 1930 UTC Day 3 Severe Thunderstorm Outlook

1 month ago
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0230 PM CDT Sun Jul 13 2025 Valid 151200Z - 161200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE UPPER MIDWEST TO THE CENTRAL HIGH PLAINS AND ACROSS THE MID MISSISSIPPI VALLEY... ...SUMMARY... Isolated strong to severe thunderstorms are possible Tuesday afternoon and evening across portions of the central Plains to Upper Midwest and Mid Mississippi Valley. ...Northern/Central Plains to the Upper Midwest... A broad upper trough and multiple convectively enhanced shortwave perturbations moving out of southern Canada should move east/southeastward over the Northern Rockies Tuesday. A belt of enhanced mid-level flow (30-40 kt) will also spread eastward, overlapping with a sagging cold front from the western Great Lakes, across the northern Plains and into the Rockies. Along and south of the front, rich low-level moisture is expected with dewpoints in the upper 60s to low 70s F contributing to 2500-3000 J/kg of MLCAPE. Ascent from the approach trough and flow aloft will aid in deepening a lee low across the central High Plains at the junction of the front and a prominent lee trough. Convergence along these features, should support scattered thunderstorms Tuesday afternoon and evening. With deep-layer shear increasing to 30-35 kt, scattered thunderstorms organized into multicell clusters or supercell structures is possible along the cold front from the eastern Dakotas to the western Great Lakes and within the broader warm sector across southern SD to central NE. More isolated storms will also be possible along and east of the lee trough trailing the surface low to the south. Steep low mid-level lapse rates of 8+ C/km will be more than sufficient for isolated severe storms capable of damaging gusts and some hail. Consideration was given to higher severe probabilities given large forecast buoyancy and more focused forcing along the front/triple point. However, variability in the timing of the front and overnight convective influences at this range lend low confidence to any one solution. At least an isolated severe risk should also extend westward within the post-front upslope regime across far southern MT and into eastern WY and western SD. While buoyancy will be reduced, low-level moist advection and upslope flow behind the front will support isolated to widely scattered storms within enhanced mid-level flow. Hail and isolated damaging gusts are possible. ...Mid MS Valley... Multiple model solutions show a rather well-defined MCV moving out of the southern Plains and Ozarks into the mid MS Valley by Tuesday morning. A very warm and humid air mass will remain in place ahead of this feature supporting sufficient buoyancy for scattered thunderstorms. The exact placement and intensity of this feature remains very uncertain owing to different mesoscale solutions/convective influence in the coming days. Still, some enhancement of the low/mid-level flow field could support some organized clusters capable of damaging gusts. ..Lyons.. 07/13/2025 Read more

SPC Jul 13, 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 1231 PM CDT Sun Jul 13 2025 Valid 141200Z - 151200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM SOUTHERN NEW ENGLAND TO THE MID ATLANTIC AND THE NORTHERN ROCKIES/PLAINS... ...SUMMARY... Isolated strong to severe thunderstorms are possible across portions of the northern Plains/Rockies and across the Mid Atlantic and Southern New England Monday. ...Mid Atlantic to southern New England... Weak troughing at the northern periphery of the subtropical ridge will shift northward across parts of the Northeast Monday. At the surface, a wind shift/weak front will move from the eastern Great Lakes into the upper OH/St Lawrence Valley by early afternoon. A very warm and humid air mass is in place east of the front with dewpoints in the 70s F expected. Despite some lingering cloud cover, diurnal heating should support moderate destabilization over much of the Northeast. Widespread thunderstorm activity is expected along and ahead of the surface boundary from northern VA into southern NY. Slight enhancement of the flow aloft to near 20 kt from the approaching shortwave could be enough to foster some longer-lived clusters with damaging gust potential from northern VA into southern NY. Elsewhere across the East, confidence in storm coverage/damaging wind potential is lower, but any stronger storms will remain cable of damaging outflow gusts from heavily water-loaded downdrafts. ...Northern Rockies and Plains... An upper trough, forecast to emanate from southern Canada, will move eastward over the northern Rockies/Plains Monday and Monday night. Ascent from this feature will overspread a weak cold front and lee trough/low, that will serve as a focus for scattered thunderstorms through afternoon and evening. Along the southern fringes of enhanced westerly flow aloft, a mix of multicells and transient supercells is expected. Modest surface moisture and deep boundary-layer mixing will support moderate buoyancy atop inverted-v structures favorable for damaging gusts and some hail with storms from northern WY into the western Dakotas. Late in the evening and into the overnight hours, low-level warm advection and continued ascent from the upper trough are expected to intensify along and north of the cold front from eastern MT into ND. A belt of strong mid-level flow (35-50 kt) will overlap with elevated destabilization north of the front. While not overly robust, sufficient buoyancy (MUCAPE ~1000 J/kg) and elongated hodographs should support a few organized elevated storms (including supercell structures) capable of isolated hail. ...Southeast States... A seasonably warm and moist air mass will again reside across much of the southeastern US beneath broad subtropical ridging aloft. Scattered to numerous storms expected Monday afternoon and evening amid strong diurnal heating and weak background ascent. With PWATs near or exceeding two inches and moderate buoyancy, a few stronger thunderstorm clusters may develop. With weak vertical shear below 15 kt, organized storms on a widespread basis are not expected. Still, sporadic damaging gusts from wet microbursts are possible. ..Lyons.. 07/13/2025 Read more