Severe Storms

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook RESENT 1 NWS Storm Prediction Center Norman OK 1146 AM CDT Wed Aug 13 2025 Valid 131630Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTH DAKOTA AND NORTH-CENTRAL NEBRASKA... ...SUMMARY... Scattered severe wind gusts and isolated large hail may occur across parts of the northern/central Plains this evening and overnight. Thunderstorms across portions of the Northeast and Mid-Atlantic may produce occasional damaging winds this afternoon. ...Northern/Central Plains... Recent satellite imagery shows a low-amplitude shortwave trough moving through southwest MT. This shortwave is forecast to continue eastward along the MT/WY border vicinity today, before continuing through the Dakotas/NE tonight. The airmass preceding this shortwave across southeast MT/northeast WY is relatively dry, with dewpoints currently in the low to mid 50s. Greater low-level moisture is in place farther east, with dewpoints increasing into the low 60s across south-central SD and north-central NE. Southerly low-level flow is anticipated throughout the day, helping to offset some of the mixing expected amid strong diurnal heating. This should result in a modestly moist, deeply mixed airmass across the southeast MT/northeast WY/western SD vicinity by the late afternoon when the forcing for ascent attendant to the approaching shortwave reaches the region. This modest large-scale ascent show work in tandem with robust daytime heating and localized orographic effects near the Black Hills to initiate thunderstorms. High-based storms are anticipated initially, which could result in strong outflow with any more mature storms. A few instances of hail as possible as well. Greater low-level moisture and buoyancy will be in place farther east (i.e. into more of western/central SD), which will combine with persistent large-scale forcing for ascent and a strengthening low-level jet to support upscale growth into a convective line. This should foster a continued threat for damaging gusts into south-central SD and far north-central NE this evening. The threat should diminish with eastern extent given nocturnal stabilization and increasing convective inhibition. ...Northeast/Mid-Atlantic... Dewpoints currently range from the low 70s over the northern Mid-Atlantic into the low 60s across northern NH/VT. Thunderstorms are already developing within this moist and moderately buoyant airmass as large-scale ascent attendant to upper troughing advancing eastward over Ontario/Quebec glances the region. Deep-layer vertical shear is expected to remain weak throughout the day (i.e. effective bulk shear generally less than 25 kt), which should limit overall storm strength and organization. Even so, steep low-level lapse rates could aid in the development of occasionally damaging gusts with any of the deeper convective cores. Greater buoyancy could result in a relatively higher probability for damaging gusts from the NY Hudson Valley into eastern PA/NJ. Refer to recently issued MCD #1938 for additional information. ..Mosier/Squitieri.. 08/13/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook RESENT 1 NWS Storm Prediction Center Norman OK 1146 AM CDT Wed Aug 13 2025 Valid 131630Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTH DAKOTA AND NORTH-CENTRAL NEBRASKA... ...SUMMARY... Scattered severe wind gusts and isolated large hail may occur across parts of the northern/central Plains this evening and overnight. Thunderstorms across portions of the Northeast and Mid-Atlantic may produce occasional damaging winds this afternoon. ...Northern/Central Plains... Recent satellite imagery shows a low-amplitude shortwave trough moving through southwest MT. This shortwave is forecast to continue eastward along the MT/WY border vicinity today, before continuing through the Dakotas/NE tonight. The airmass preceding this shortwave across southeast MT/northeast WY is relatively dry, with dewpoints currently in the low to mid 50s. Greater low-level moisture is in place farther east, with dewpoints increasing into the low 60s across south-central SD and north-central NE. Southerly low-level flow is anticipated throughout the day, helping to offset some of the mixing expected amid strong diurnal heating. This should result in a modestly moist, deeply mixed airmass across the southeast MT/northeast WY/western SD vicinity by the late afternoon when the forcing for ascent attendant to the approaching shortwave reaches the region. This modest large-scale ascent show work in tandem with robust daytime heating and localized orographic effects near the Black Hills to initiate thunderstorms. High-based storms are anticipated initially, which could result in strong outflow with any more mature storms. A few instances of hail as possible as well. Greater low-level moisture and buoyancy will be in place farther east (i.e. into more of western/central SD), which will combine with persistent large-scale forcing for ascent and a strengthening low-level jet to support upscale growth into a convective line. This should foster a continued threat for damaging gusts into south-central SD and far north-central NE this evening. The threat should diminish with eastern extent given nocturnal stabilization and increasing convective inhibition. ...Northeast/Mid-Atlantic... Dewpoints currently range from the low 70s over the northern Mid-Atlantic into the low 60s across northern NH/VT. Thunderstorms are already developing within this moist and moderately buoyant airmass as large-scale ascent attendant to upper troughing advancing eastward over Ontario/Quebec glances the region. Deep-layer vertical shear is expected to remain weak throughout the day (i.e. effective bulk shear generally less than 25 kt), which should limit overall storm strength and organization. Even so, steep low-level lapse rates could aid in the development of occasionally damaging gusts with any of the deeper convective cores. Greater buoyancy could result in a relatively higher probability for damaging gusts from the NY Hudson Valley into eastern PA/NJ. Refer to recently issued MCD #1938 for additional information. ..Mosier/Squitieri.. 08/13/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook RESENT 1 NWS Storm Prediction Center Norman OK 1146 AM CDT Wed Aug 13 2025 Valid 131630Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTH DAKOTA AND NORTH-CENTRAL NEBRASKA... ...SUMMARY... Scattered severe wind gusts and isolated large hail may occur across parts of the northern/central Plains this evening and overnight. Thunderstorms across portions of the Northeast and Mid-Atlantic may produce occasional damaging winds this afternoon. ...Northern/Central Plains... Recent satellite imagery shows a low-amplitude shortwave trough moving through southwest MT. This shortwave is forecast to continue eastward along the MT/WY border vicinity today, before continuing through the Dakotas/NE tonight. The airmass preceding this shortwave across southeast MT/northeast WY is relatively dry, with dewpoints currently in the low to mid 50s. Greater low-level moisture is in place farther east, with dewpoints increasing into the low 60s across south-central SD and north-central NE. Southerly low-level flow is anticipated throughout the day, helping to offset some of the mixing expected amid strong diurnal heating. This should result in a modestly moist, deeply mixed airmass across the southeast MT/northeast WY/western SD vicinity by the late afternoon when the forcing for ascent attendant to the approaching shortwave reaches the region. This modest large-scale ascent show work in tandem with robust daytime heating and localized orographic effects near the Black Hills to initiate thunderstorms. High-based storms are anticipated initially, which could result in strong outflow with any more mature storms. A few instances of hail as possible as well. Greater low-level moisture and buoyancy will be in place farther east (i.e. into more of western/central SD), which will combine with persistent large-scale forcing for ascent and a strengthening low-level jet to support upscale growth into a convective line. This should foster a continued threat for damaging gusts into south-central SD and far north-central NE this evening. The threat should diminish with eastern extent given nocturnal stabilization and increasing convective inhibition. ...Northeast/Mid-Atlantic... Dewpoints currently range from the low 70s over the northern Mid-Atlantic into the low 60s across northern NH/VT. Thunderstorms are already developing within this moist and moderately buoyant airmass as large-scale ascent attendant to upper troughing advancing eastward over Ontario/Quebec glances the region. Deep-layer vertical shear is expected to remain weak throughout the day (i.e. effective bulk shear generally less than 25 kt), which should limit overall storm strength and organization. Even so, steep low-level lapse rates could aid in the development of occasionally damaging gusts with any of the deeper convective cores. Greater buoyancy could result in a relatively higher probability for damaging gusts from the NY Hudson Valley into eastern PA/NJ. Refer to recently issued MCD #1938 for additional information. ..Mosier/Squitieri.. 08/13/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook RESENT 1 NWS Storm Prediction Center Norman OK 1146 AM CDT Wed Aug 13 2025 Valid 131630Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTH DAKOTA AND NORTH-CENTRAL NEBRASKA... ...SUMMARY... Scattered severe wind gusts and isolated large hail may occur across parts of the northern/central Plains this evening and overnight. Thunderstorms across portions of the Northeast and Mid-Atlantic may produce occasional damaging winds this afternoon. ...Northern/Central Plains... Recent satellite imagery shows a low-amplitude shortwave trough moving through southwest MT. This shortwave is forecast to continue eastward along the MT/WY border vicinity today, before continuing through the Dakotas/NE tonight. The airmass preceding this shortwave across southeast MT/northeast WY is relatively dry, with dewpoints currently in the low to mid 50s. Greater low-level moisture is in place farther east, with dewpoints increasing into the low 60s across south-central SD and north-central NE. Southerly low-level flow is anticipated throughout the day, helping to offset some of the mixing expected amid strong diurnal heating. This should result in a modestly moist, deeply mixed airmass across the southeast MT/northeast WY/western SD vicinity by the late afternoon when the forcing for ascent attendant to the approaching shortwave reaches the region. This modest large-scale ascent show work in tandem with robust daytime heating and localized orographic effects near the Black Hills to initiate thunderstorms. High-based storms are anticipated initially, which could result in strong outflow with any more mature storms. A few instances of hail as possible as well. Greater low-level moisture and buoyancy will be in place farther east (i.e. into more of western/central SD), which will combine with persistent large-scale forcing for ascent and a strengthening low-level jet to support upscale growth into a convective line. This should foster a continued threat for damaging gusts into south-central SD and far north-central NE this evening. The threat should diminish with eastern extent given nocturnal stabilization and increasing convective inhibition. ...Northeast/Mid-Atlantic... Dewpoints currently range from the low 70s over the northern Mid-Atlantic into the low 60s across northern NH/VT. Thunderstorms are already developing within this moist and moderately buoyant airmass as large-scale ascent attendant to upper troughing advancing eastward over Ontario/Quebec glances the region. Deep-layer vertical shear is expected to remain weak throughout the day (i.e. effective bulk shear generally less than 25 kt), which should limit overall storm strength and organization. Even so, steep low-level lapse rates could aid in the development of occasionally damaging gusts with any of the deeper convective cores. Greater buoyancy could result in a relatively higher probability for damaging gusts from the NY Hudson Valley into eastern PA/NJ. Refer to recently issued MCD #1938 for additional information. ..Mosier/Squitieri.. 08/13/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook RESENT 1 NWS Storm Prediction Center Norman OK 1146 AM CDT Wed Aug 13 2025 Valid 131630Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTH DAKOTA AND NORTH-CENTRAL NEBRASKA... ...SUMMARY... Scattered severe wind gusts and isolated large hail may occur across parts of the northern/central Plains this evening and overnight. Thunderstorms across portions of the Northeast and Mid-Atlantic may produce occasional damaging winds this afternoon. ...Northern/Central Plains... Recent satellite imagery shows a low-amplitude shortwave trough moving through southwest MT. This shortwave is forecast to continue eastward along the MT/WY border vicinity today, before continuing through the Dakotas/NE tonight. The airmass preceding this shortwave across southeast MT/northeast WY is relatively dry, with dewpoints currently in the low to mid 50s. Greater low-level moisture is in place farther east, with dewpoints increasing into the low 60s across south-central SD and north-central NE. Southerly low-level flow is anticipated throughout the day, helping to offset some of the mixing expected amid strong diurnal heating. This should result in a modestly moist, deeply mixed airmass across the southeast MT/northeast WY/western SD vicinity by the late afternoon when the forcing for ascent attendant to the approaching shortwave reaches the region. This modest large-scale ascent show work in tandem with robust daytime heating and localized orographic effects near the Black Hills to initiate thunderstorms. High-based storms are anticipated initially, which could result in strong outflow with any more mature storms. A few instances of hail as possible as well. Greater low-level moisture and buoyancy will be in place farther east (i.e. into more of western/central SD), which will combine with persistent large-scale forcing for ascent and a strengthening low-level jet to support upscale growth into a convective line. This should foster a continued threat for damaging gusts into south-central SD and far north-central NE this evening. The threat should diminish with eastern extent given nocturnal stabilization and increasing convective inhibition. ...Northeast/Mid-Atlantic... Dewpoints currently range from the low 70s over the northern Mid-Atlantic into the low 60s across northern NH/VT. Thunderstorms are already developing within this moist and moderately buoyant airmass as large-scale ascent attendant to upper troughing advancing eastward over Ontario/Quebec glances the region. Deep-layer vertical shear is expected to remain weak throughout the day (i.e. effective bulk shear generally less than 25 kt), which should limit overall storm strength and organization. Even so, steep low-level lapse rates could aid in the development of occasionally damaging gusts with any of the deeper convective cores. Greater buoyancy could result in a relatively higher probability for damaging gusts from the NY Hudson Valley into eastern PA/NJ. Refer to recently issued MCD #1938 for additional information. ..Mosier/Squitieri.. 08/13/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook RESENT 1 NWS Storm Prediction Center Norman OK 1146 AM CDT Wed Aug 13 2025 Valid 131630Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTH DAKOTA AND NORTH-CENTRAL NEBRASKA... ...SUMMARY... Scattered severe wind gusts and isolated large hail may occur across parts of the northern/central Plains this evening and overnight. Thunderstorms across portions of the Northeast and Mid-Atlantic may produce occasional damaging winds this afternoon. ...Northern/Central Plains... Recent satellite imagery shows a low-amplitude shortwave trough moving through southwest MT. This shortwave is forecast to continue eastward along the MT/WY border vicinity today, before continuing through the Dakotas/NE tonight. The airmass preceding this shortwave across southeast MT/northeast WY is relatively dry, with dewpoints currently in the low to mid 50s. Greater low-level moisture is in place farther east, with dewpoints increasing into the low 60s across south-central SD and north-central NE. Southerly low-level flow is anticipated throughout the day, helping to offset some of the mixing expected amid strong diurnal heating. This should result in a modestly moist, deeply mixed airmass across the southeast MT/northeast WY/western SD vicinity by the late afternoon when the forcing for ascent attendant to the approaching shortwave reaches the region. This modest large-scale ascent show work in tandem with robust daytime heating and localized orographic effects near the Black Hills to initiate thunderstorms. High-based storms are anticipated initially, which could result in strong outflow with any more mature storms. A few instances of hail as possible as well. Greater low-level moisture and buoyancy will be in place farther east (i.e. into more of western/central SD), which will combine with persistent large-scale forcing for ascent and a strengthening low-level jet to support upscale growth into a convective line. This should foster a continued threat for damaging gusts into south-central SD and far north-central NE this evening. The threat should diminish with eastern extent given nocturnal stabilization and increasing convective inhibition. ...Northeast/Mid-Atlantic... Dewpoints currently range from the low 70s over the northern Mid-Atlantic into the low 60s across northern NH/VT. Thunderstorms are already developing within this moist and moderately buoyant airmass as large-scale ascent attendant to upper troughing advancing eastward over Ontario/Quebec glances the region. Deep-layer vertical shear is expected to remain weak throughout the day (i.e. effective bulk shear generally less than 25 kt), which should limit overall storm strength and organization. Even so, steep low-level lapse rates could aid in the development of occasionally damaging gusts with any of the deeper convective cores. Greater buoyancy could result in a relatively higher probability for damaging gusts from the NY Hudson Valley into eastern PA/NJ. Refer to recently issued MCD #1938 for additional information. ..Mosier/Squitieri.. 08/13/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook RESENT 1 NWS Storm Prediction Center Norman OK 1146 AM CDT Wed Aug 13 2025 Valid 131630Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTH DAKOTA AND NORTH-CENTRAL NEBRASKA... ...SUMMARY... Scattered severe wind gusts and isolated large hail may occur across parts of the northern/central Plains this evening and overnight. Thunderstorms across portions of the Northeast and Mid-Atlantic may produce occasional damaging winds this afternoon. ...Northern/Central Plains... Recent satellite imagery shows a low-amplitude shortwave trough moving through southwest MT. This shortwave is forecast to continue eastward along the MT/WY border vicinity today, before continuing through the Dakotas/NE tonight. The airmass preceding this shortwave across southeast MT/northeast WY is relatively dry, with dewpoints currently in the low to mid 50s. Greater low-level moisture is in place farther east, with dewpoints increasing into the low 60s across south-central SD and north-central NE. Southerly low-level flow is anticipated throughout the day, helping to offset some of the mixing expected amid strong diurnal heating. This should result in a modestly moist, deeply mixed airmass across the southeast MT/northeast WY/western SD vicinity by the late afternoon when the forcing for ascent attendant to the approaching shortwave reaches the region. This modest large-scale ascent show work in tandem with robust daytime heating and localized orographic effects near the Black Hills to initiate thunderstorms. High-based storms are anticipated initially, which could result in strong outflow with any more mature storms. A few instances of hail as possible as well. Greater low-level moisture and buoyancy will be in place farther east (i.e. into more of western/central SD), which will combine with persistent large-scale forcing for ascent and a strengthening low-level jet to support upscale growth into a convective line. This should foster a continued threat for damaging gusts into south-central SD and far north-central NE this evening. The threat should diminish with eastern extent given nocturnal stabilization and increasing convective inhibition. ...Northeast/Mid-Atlantic... Dewpoints currently range from the low 70s over the northern Mid-Atlantic into the low 60s across northern NH/VT. Thunderstorms are already developing within this moist and moderately buoyant airmass as large-scale ascent attendant to upper troughing advancing eastward over Ontario/Quebec glances the region. Deep-layer vertical shear is expected to remain weak throughout the day (i.e. effective bulk shear generally less than 25 kt), which should limit overall storm strength and organization. Even so, steep low-level lapse rates could aid in the development of occasionally damaging gusts with any of the deeper convective cores. Greater buoyancy could result in a relatively higher probability for damaging gusts from the NY Hudson Valley into eastern PA/NJ. Refer to recently issued MCD #1938 for additional information. ..Mosier/Squitieri.. 08/13/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook RESENT 1 NWS Storm Prediction Center Norman OK 1146 AM CDT Wed Aug 13 2025 Valid 131630Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTH DAKOTA AND NORTH-CENTRAL NEBRASKA... ...SUMMARY... Scattered severe wind gusts and isolated large hail may occur across parts of the northern/central Plains this evening and overnight. Thunderstorms across portions of the Northeast and Mid-Atlantic may produce occasional damaging winds this afternoon. ...Northern/Central Plains... Recent satellite imagery shows a low-amplitude shortwave trough moving through southwest MT. This shortwave is forecast to continue eastward along the MT/WY border vicinity today, before continuing through the Dakotas/NE tonight. The airmass preceding this shortwave across southeast MT/northeast WY is relatively dry, with dewpoints currently in the low to mid 50s. Greater low-level moisture is in place farther east, with dewpoints increasing into the low 60s across south-central SD and north-central NE. Southerly low-level flow is anticipated throughout the day, helping to offset some of the mixing expected amid strong diurnal heating. This should result in a modestly moist, deeply mixed airmass across the southeast MT/northeast WY/western SD vicinity by the late afternoon when the forcing for ascent attendant to the approaching shortwave reaches the region. This modest large-scale ascent show work in tandem with robust daytime heating and localized orographic effects near the Black Hills to initiate thunderstorms. High-based storms are anticipated initially, which could result in strong outflow with any more mature storms. A few instances of hail as possible as well. Greater low-level moisture and buoyancy will be in place farther east (i.e. into more of western/central SD), which will combine with persistent large-scale forcing for ascent and a strengthening low-level jet to support upscale growth into a convective line. This should foster a continued threat for damaging gusts into south-central SD and far north-central NE this evening. The threat should diminish with eastern extent given nocturnal stabilization and increasing convective inhibition. ...Northeast/Mid-Atlantic... Dewpoints currently range from the low 70s over the northern Mid-Atlantic into the low 60s across northern NH/VT. Thunderstorms are already developing within this moist and moderately buoyant airmass as large-scale ascent attendant to upper troughing advancing eastward over Ontario/Quebec glances the region. Deep-layer vertical shear is expected to remain weak throughout the day (i.e. effective bulk shear generally less than 25 kt), which should limit overall storm strength and organization. Even so, steep low-level lapse rates could aid in the development of occasionally damaging gusts with any of the deeper convective cores. Greater buoyancy could result in a relatively higher probability for damaging gusts from the NY Hudson Valley into eastern PA/NJ. Refer to recently issued MCD #1938 for additional information. ..Mosier/Squitieri.. 08/13/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Wed Aug 13 2025 Valid 131630Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTH DAKOTA AND NORTH-CENTRAL NEBRASKA... ...SUMMARY... Scattered severe wind gusts and isolated large hail may occur across parts of the northern/central Plains this evening and overnight. Thunderstorms across portions of the Northeast and Mid-Atlantic may produce occasional damaging winds this afternoon. ...Northern/Central Plains... Recent satellite imagery shows a low-amplitude shortwave trough moving through southwest MT. This shortwave is forecast to continue eastward along the MT/WY border vicinity today, before continuing through the Dakotas/NE tonight. The airmass preceding this shortwave across southeast MT/northeast WY is relatively dry, with dewpoints currently in the low to mid 50s. Greater low-level moisture is in place farther east, with dewpoints increasing into the low 60s across south-central SD and north-central NE. Southerly low-level flow is anticipated throughout the day, helping to offset some of the mixing expected amid strong diurnal heating. This should result in a modestly moist, deeply mixed airmass across the southeast MT/northeast WY/western SD vicinity by the late afternoon when the forcing for ascent attendant to the approaching shortwave reaches the region. This modest large-scale ascent show work in tandem with robust daytime heating and localized orographic effects near the Black Hills to initiate thunderstorms. High-based storms are anticipated initially, which could result in strong outflow with any more mature storms. A few instances of hail as possible as well. Greater low-level moisture and buoyancy will be in place farther east (i.e. into more of western/central SD), which will combine with persistent large-scale forcing for ascent and a strengthening low-level jet to support upscale growth into a convective line. This should foster a continued threat for damaging gusts into south-central SD and far north-central NE this evening. The threat should diminish with eastern extent given nocturnal stabilization and increasing convective inhibition. ...Northeast/Mid-Atlantic... Dewpoints currently range from the low 70s over the northern Mid-Atlantic into the low 60s across northern NH/VT. Thunderstorms are already developing within this moist and moderately buoyant airmass as large-scale ascent attendant to upper troughing advancing eastward over Ontario/Quebec glances the region. Deep-layer vertical shear is expected to remain weak throughout the day (i.e. effective bulk shear generally less than 25 kt), which should limit overall storm strength and organization. Even so, steep low-level lapse rates could aid in the development of occasionally damaging gusts with any of the deeper convective cores. Greater buoyancy could result in a relatively higher probability for damaging gusts from the NY Hudson Valley into eastern PA/NJ. Refer to recently issued MCD #1938 for additional information. ..Mosier/Squitieri.. 08/13/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0738 AM CDT Wed Aug 13 2025 Valid 131300Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTH DAKOTA AND NORTH-CENTRAL NEBRASKA... ...SUMMARY... Scattered severe wind gusts and isolated large hail may occur across parts of the northern/central Plains this evening and overnight. Thunderstorms across portions of the Northeast and Mid-Atlantic may produce occasional damaging winds this afternoon. ...Northern/Central Plains... The primary upper trough will remain over western/central Canada today, with quasi-zonal westerly mid-level flow continuing over much of the northern Rockies/Plains through the period. A subtle/low-amplitude shortwave trough over parts of ID/western MT this morning associated with ongoing weak convection is forecast to advance eastward towards eastern MT/WY and the western Dakotas by early this evening. Gradually warming low/mid-level temperatures and a stout cap will likely hinder surface-based convective development across much of the northern/central Plains until mid to late afternoon at the earliest. Still, the modest large-scale ascent associated with the approaching shortwave trough may be sufficient in tandem with robust daytime heating and localized orographic effects near the Black Hills to initiate thunderstorms. Modest low-level moisture will continue to stream northward today along/east of a surface lee trough. Initially high-based convection across the northern/central High Plains could pose an isolated threat for mainly severe gusts as it continues eastwards towards greater low-level moisture and MLCAPE. The best potential for a more focused corridor of severe winds and isolated large hail still appears generally along/east-southeast of the Black Hills towards central SD and perhaps north-central NE this evening into the early overnight hours. Here, moderate instability and deep-layer shear should overlap with a very well-mixed boundary layer, supporting a severe wind threat with any cluster that can become established amid a gradually strengthening low-level jet. Some uncertainty still remains regarding this potential, however, as low/mid-level temperatures (around 850-700 mb) are forecast to remain quite warm. ...Northeast/Mid-Atlantic... The Northeast and portions of the Mid-Atlantic will experience the glancing influence of upper troughing advancing eastward over Ontario/Quebec today. A moist low-level airmass is already in place ahead of a weak surface front extending southwestward from the Great Lakes into the Midwest. Although lapse rates aloft will remain poor through the afternoon, diurnal heating ahead of ongoing showers and thunderstorms this morning should promote weak to locally moderate instability from New England to parts of the Mid-Atlantic. Generally modest mid-level flow (around 15-25 kt at 500 mb) should tend to limit deep-layer shear given weak winds at low levels. Even so, loosely organized clusters may still pose some threat for isolated damaging winds this afternoon and early evening as convection spreads eastward amid a boundary layer characterized by steepened low-level lapse rates. ..Gleason/Leitman.. 08/13/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0738 AM CDT Wed Aug 13 2025 Valid 131300Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTH DAKOTA AND NORTH-CENTRAL NEBRASKA... ...SUMMARY... Scattered severe wind gusts and isolated large hail may occur across parts of the northern/central Plains this evening and overnight. Thunderstorms across portions of the Northeast and Mid-Atlantic may produce occasional damaging winds this afternoon. ...Northern/Central Plains... The primary upper trough will remain over western/central Canada today, with quasi-zonal westerly mid-level flow continuing over much of the northern Rockies/Plains through the period. A subtle/low-amplitude shortwave trough over parts of ID/western MT this morning associated with ongoing weak convection is forecast to advance eastward towards eastern MT/WY and the western Dakotas by early this evening. Gradually warming low/mid-level temperatures and a stout cap will likely hinder surface-based convective development across much of the northern/central Plains until mid to late afternoon at the earliest. Still, the modest large-scale ascent associated with the approaching shortwave trough may be sufficient in tandem with robust daytime heating and localized orographic effects near the Black Hills to initiate thunderstorms. Modest low-level moisture will continue to stream northward today along/east of a surface lee trough. Initially high-based convection across the northern/central High Plains could pose an isolated threat for mainly severe gusts as it continues eastwards towards greater low-level moisture and MLCAPE. The best potential for a more focused corridor of severe winds and isolated large hail still appears generally along/east-southeast of the Black Hills towards central SD and perhaps north-central NE this evening into the early overnight hours. Here, moderate instability and deep-layer shear should overlap with a very well-mixed boundary layer, supporting a severe wind threat with any cluster that can become established amid a gradually strengthening low-level jet. Some uncertainty still remains regarding this potential, however, as low/mid-level temperatures (around 850-700 mb) are forecast to remain quite warm. ...Northeast/Mid-Atlantic... The Northeast and portions of the Mid-Atlantic will experience the glancing influence of upper troughing advancing eastward over Ontario/Quebec today. A moist low-level airmass is already in place ahead of a weak surface front extending southwestward from the Great Lakes into the Midwest. Although lapse rates aloft will remain poor through the afternoon, diurnal heating ahead of ongoing showers and thunderstorms this morning should promote weak to locally moderate instability from New England to parts of the Mid-Atlantic. Generally modest mid-level flow (around 15-25 kt at 500 mb) should tend to limit deep-layer shear given weak winds at low levels. Even so, loosely organized clusters may still pose some threat for isolated damaging winds this afternoon and early evening as convection spreads eastward amid a boundary layer characterized by steepened low-level lapse rates. ..Gleason/Leitman.. 08/13/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0738 AM CDT Wed Aug 13 2025 Valid 131300Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTH DAKOTA AND NORTH-CENTRAL NEBRASKA... ...SUMMARY... Scattered severe wind gusts and isolated large hail may occur across parts of the northern/central Plains this evening and overnight. Thunderstorms across portions of the Northeast and Mid-Atlantic may produce occasional damaging winds this afternoon. ...Northern/Central Plains... The primary upper trough will remain over western/central Canada today, with quasi-zonal westerly mid-level flow continuing over much of the northern Rockies/Plains through the period. A subtle/low-amplitude shortwave trough over parts of ID/western MT this morning associated with ongoing weak convection is forecast to advance eastward towards eastern MT/WY and the western Dakotas by early this evening. Gradually warming low/mid-level temperatures and a stout cap will likely hinder surface-based convective development across much of the northern/central Plains until mid to late afternoon at the earliest. Still, the modest large-scale ascent associated with the approaching shortwave trough may be sufficient in tandem with robust daytime heating and localized orographic effects near the Black Hills to initiate thunderstorms. Modest low-level moisture will continue to stream northward today along/east of a surface lee trough. Initially high-based convection across the northern/central High Plains could pose an isolated threat for mainly severe gusts as it continues eastwards towards greater low-level moisture and MLCAPE. The best potential for a more focused corridor of severe winds and isolated large hail still appears generally along/east-southeast of the Black Hills towards central SD and perhaps north-central NE this evening into the early overnight hours. Here, moderate instability and deep-layer shear should overlap with a very well-mixed boundary layer, supporting a severe wind threat with any cluster that can become established amid a gradually strengthening low-level jet. Some uncertainty still remains regarding this potential, however, as low/mid-level temperatures (around 850-700 mb) are forecast to remain quite warm. ...Northeast/Mid-Atlantic... The Northeast and portions of the Mid-Atlantic will experience the glancing influence of upper troughing advancing eastward over Ontario/Quebec today. A moist low-level airmass is already in place ahead of a weak surface front extending southwestward from the Great Lakes into the Midwest. Although lapse rates aloft will remain poor through the afternoon, diurnal heating ahead of ongoing showers and thunderstorms this morning should promote weak to locally moderate instability from New England to parts of the Mid-Atlantic. Generally modest mid-level flow (around 15-25 kt at 500 mb) should tend to limit deep-layer shear given weak winds at low levels. Even so, loosely organized clusters may still pose some threat for isolated damaging winds this afternoon and early evening as convection spreads eastward amid a boundary layer characterized by steepened low-level lapse rates. ..Gleason/Leitman.. 08/13/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0738 AM CDT Wed Aug 13 2025 Valid 131300Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTH DAKOTA AND NORTH-CENTRAL NEBRASKA... ...SUMMARY... Scattered severe wind gusts and isolated large hail may occur across parts of the northern/central Plains this evening and overnight. Thunderstorms across portions of the Northeast and Mid-Atlantic may produce occasional damaging winds this afternoon. ...Northern/Central Plains... The primary upper trough will remain over western/central Canada today, with quasi-zonal westerly mid-level flow continuing over much of the northern Rockies/Plains through the period. A subtle/low-amplitude shortwave trough over parts of ID/western MT this morning associated with ongoing weak convection is forecast to advance eastward towards eastern MT/WY and the western Dakotas by early this evening. Gradually warming low/mid-level temperatures and a stout cap will likely hinder surface-based convective development across much of the northern/central Plains until mid to late afternoon at the earliest. Still, the modest large-scale ascent associated with the approaching shortwave trough may be sufficient in tandem with robust daytime heating and localized orographic effects near the Black Hills to initiate thunderstorms. Modest low-level moisture will continue to stream northward today along/east of a surface lee trough. Initially high-based convection across the northern/central High Plains could pose an isolated threat for mainly severe gusts as it continues eastwards towards greater low-level moisture and MLCAPE. The best potential for a more focused corridor of severe winds and isolated large hail still appears generally along/east-southeast of the Black Hills towards central SD and perhaps north-central NE this evening into the early overnight hours. Here, moderate instability and deep-layer shear should overlap with a very well-mixed boundary layer, supporting a severe wind threat with any cluster that can become established amid a gradually strengthening low-level jet. Some uncertainty still remains regarding this potential, however, as low/mid-level temperatures (around 850-700 mb) are forecast to remain quite warm. ...Northeast/Mid-Atlantic... The Northeast and portions of the Mid-Atlantic will experience the glancing influence of upper troughing advancing eastward over Ontario/Quebec today. A moist low-level airmass is already in place ahead of a weak surface front extending southwestward from the Great Lakes into the Midwest. Although lapse rates aloft will remain poor through the afternoon, diurnal heating ahead of ongoing showers and thunderstorms this morning should promote weak to locally moderate instability from New England to parts of the Mid-Atlantic. Generally modest mid-level flow (around 15-25 kt at 500 mb) should tend to limit deep-layer shear given weak winds at low levels. Even so, loosely organized clusters may still pose some threat for isolated damaging winds this afternoon and early evening as convection spreads eastward amid a boundary layer characterized by steepened low-level lapse rates. ..Gleason/Leitman.. 08/13/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0738 AM CDT Wed Aug 13 2025 Valid 131300Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTH DAKOTA AND NORTH-CENTRAL NEBRASKA... ...SUMMARY... Scattered severe wind gusts and isolated large hail may occur across parts of the northern/central Plains this evening and overnight. Thunderstorms across portions of the Northeast and Mid-Atlantic may produce occasional damaging winds this afternoon. ...Northern/Central Plains... The primary upper trough will remain over western/central Canada today, with quasi-zonal westerly mid-level flow continuing over much of the northern Rockies/Plains through the period. A subtle/low-amplitude shortwave trough over parts of ID/western MT this morning associated with ongoing weak convection is forecast to advance eastward towards eastern MT/WY and the western Dakotas by early this evening. Gradually warming low/mid-level temperatures and a stout cap will likely hinder surface-based convective development across much of the northern/central Plains until mid to late afternoon at the earliest. Still, the modest large-scale ascent associated with the approaching shortwave trough may be sufficient in tandem with robust daytime heating and localized orographic effects near the Black Hills to initiate thunderstorms. Modest low-level moisture will continue to stream northward today along/east of a surface lee trough. Initially high-based convection across the northern/central High Plains could pose an isolated threat for mainly severe gusts as it continues eastwards towards greater low-level moisture and MLCAPE. The best potential for a more focused corridor of severe winds and isolated large hail still appears generally along/east-southeast of the Black Hills towards central SD and perhaps north-central NE this evening into the early overnight hours. Here, moderate instability and deep-layer shear should overlap with a very well-mixed boundary layer, supporting a severe wind threat with any cluster that can become established amid a gradually strengthening low-level jet. Some uncertainty still remains regarding this potential, however, as low/mid-level temperatures (around 850-700 mb) are forecast to remain quite warm. ...Northeast/Mid-Atlantic... The Northeast and portions of the Mid-Atlantic will experience the glancing influence of upper troughing advancing eastward over Ontario/Quebec today. A moist low-level airmass is already in place ahead of a weak surface front extending southwestward from the Great Lakes into the Midwest. Although lapse rates aloft will remain poor through the afternoon, diurnal heating ahead of ongoing showers and thunderstorms this morning should promote weak to locally moderate instability from New England to parts of the Mid-Atlantic. Generally modest mid-level flow (around 15-25 kt at 500 mb) should tend to limit deep-layer shear given weak winds at low levels. Even so, loosely organized clusters may still pose some threat for isolated damaging winds this afternoon and early evening as convection spreads eastward amid a boundary layer characterized by steepened low-level lapse rates. ..Gleason/Leitman.. 08/13/2025 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0344 AM CDT Wed Aug 13 2025 Valid 161200Z - 211200Z ...DISCUSSION... During the Saturday/D4 to Sunday/D5 time frame, a weak midlevel wave may affect the far northern Plains to upper Great Lakes, rounding the building upper ridge. Meanwhile, a boundary will exist roughly from ND/MN into MI, with latitudinal uncertainty. A moist air mass will remain across this zone, with periodic storm complexes possible. Predictability is low but at least some wind risk may develop across portions of this zone. For the rest of the period through at least Wednesday/D8, a large upper ridge is forecast to build over much of the West/Rockies, with minimal severe risk. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0344 AM CDT Wed Aug 13 2025 Valid 161200Z - 211200Z ...DISCUSSION... During the Saturday/D4 to Sunday/D5 time frame, a weak midlevel wave may affect the far northern Plains to upper Great Lakes, rounding the building upper ridge. Meanwhile, a boundary will exist roughly from ND/MN into MI, with latitudinal uncertainty. A moist air mass will remain across this zone, with periodic storm complexes possible. Predictability is low but at least some wind risk may develop across portions of this zone. For the rest of the period through at least Wednesday/D8, a large upper ridge is forecast to build over much of the West/Rockies, with minimal severe risk. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0344 AM CDT Wed Aug 13 2025 Valid 161200Z - 211200Z ...DISCUSSION... During the Saturday/D4 to Sunday/D5 time frame, a weak midlevel wave may affect the far northern Plains to upper Great Lakes, rounding the building upper ridge. Meanwhile, a boundary will exist roughly from ND/MN into MI, with latitudinal uncertainty. A moist air mass will remain across this zone, with periodic storm complexes possible. Predictability is low but at least some wind risk may develop across portions of this zone. For the rest of the period through at least Wednesday/D8, a large upper ridge is forecast to build over much of the West/Rockies, with minimal severe risk. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0344 AM CDT Wed Aug 13 2025 Valid 161200Z - 211200Z ...DISCUSSION... During the Saturday/D4 to Sunday/D5 time frame, a weak midlevel wave may affect the far northern Plains to upper Great Lakes, rounding the building upper ridge. Meanwhile, a boundary will exist roughly from ND/MN into MI, with latitudinal uncertainty. A moist air mass will remain across this zone, with periodic storm complexes possible. Predictability is low but at least some wind risk may develop across portions of this zone. For the rest of the period through at least Wednesday/D8, a large upper ridge is forecast to build over much of the West/Rockies, with minimal severe risk. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0344 AM CDT Wed Aug 13 2025 Valid 161200Z - 211200Z ...DISCUSSION... During the Saturday/D4 to Sunday/D5 time frame, a weak midlevel wave may affect the far northern Plains to upper Great Lakes, rounding the building upper ridge. Meanwhile, a boundary will exist roughly from ND/MN into MI, with latitudinal uncertainty. A moist air mass will remain across this zone, with periodic storm complexes possible. Predictability is low but at least some wind risk may develop across portions of this zone. For the rest of the period through at least Wednesday/D8, a large upper ridge is forecast to build over much of the West/Rockies, with minimal severe risk. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0344 AM CDT Wed Aug 13 2025 Valid 161200Z - 211200Z ...DISCUSSION... During the Saturday/D4 to Sunday/D5 time frame, a weak midlevel wave may affect the far northern Plains to upper Great Lakes, rounding the building upper ridge. Meanwhile, a boundary will exist roughly from ND/MN into MI, with latitudinal uncertainty. A moist air mass will remain across this zone, with periodic storm complexes possible. Predictability is low but at least some wind risk may develop across portions of this zone. For the rest of the period through at least Wednesday/D8, a large upper ridge is forecast to build over much of the West/Rockies, with minimal severe risk. Read more