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Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0342 AM CDT Mon Jul 07 2025 Valid 101200Z - 151200Z ...DISCUSSION... The Southwest upper ridge will gradually flatten as a more progressive mid-level flow regime becomes established over the northern CONUS later this week into early next week. Multiple pronounced mid-level troughs, with cooler temperatures aloft, will traverse the north-central U.S. and overspread rich low-level moisture. Strong buoyancy will precede these troughs, and upon lifting of this unstable airmass, at least scattered organized thunderstorm development should ensue, with multiple rounds of strong to severe storms possible. ...Day 4 (Thursday) - Northern Plains... The first in a series of mid-level troughs will eject into the northern Plains on Day 4/Thursday, encouraging surface lee troughing across the central and northern Plains. Dewpoints into the 70s F, beneath 8+ C/km mid-level lapse rates, will support strong to locally extreme instability by afternoon peak heating. The ejection of the upper trough will provide enough upper support for scattered thunderstorm development. Increasing westerly flow with height will result in straight, elongated hodographs. Supercells should be the main mode of convection, at least initially, with severe wind and hail the primary threats. ...Days 5-6 (Friday-Saturday) - Midwest toward the Great Lakes... The main mid-level trough will continue to slowly approach the Upper MS Valley as a preceding mid-level impulse continues to advance eastward. Potential exists for renewed thunderstorm development for portions of the Upper MS Valley and Midwest on Friday, spreading east with upper trough advancement toward the Great Lakes on Saturday. Rich low-level moisture beneath steep mid-level lapse rates will promote strong instability in the warm sector, amid modest vertical wind shear. Somewhere in this region, strong to severe storms are likely, with severe wind/hail the main concerns on both Friday and Saturday. The timing and location of thunderstorm initiation will be highly dependent on the position of remnant outflow boundaries from storms during previous days. Such details are quite challenging to point out this far in advance, precluding severe probabilities at this time, though probabilities will likely be needed in future outlooks. ...Days 7-8 (Sunday-Monday) - Upper Mississippi Valley... The next in a series of mid-level troughs will traverse the north-central CONUS toward the end of the period. Medium-range guidance consensus depicts extreme instability (i.e. well over 4000 J/kg MLCAPE) preceding this trough, along with strong enough westerly mid-level flow and accompanying vertical wind shear. As such, another episode of organized severe storms is possible in the Sunday/Monday time-frame. However, given the seasonal weak forcing associated with this second low-amplitude trough, run-to-run guidance consistency is desired before severe probabilities are delineated. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0342 AM CDT Mon Jul 07 2025 Valid 101200Z - 151200Z ...DISCUSSION... The Southwest upper ridge will gradually flatten as a more progressive mid-level flow regime becomes established over the northern CONUS later this week into early next week. Multiple pronounced mid-level troughs, with cooler temperatures aloft, will traverse the north-central U.S. and overspread rich low-level moisture. Strong buoyancy will precede these troughs, and upon lifting of this unstable airmass, at least scattered organized thunderstorm development should ensue, with multiple rounds of strong to severe storms possible. ...Day 4 (Thursday) - Northern Plains... The first in a series of mid-level troughs will eject into the northern Plains on Day 4/Thursday, encouraging surface lee troughing across the central and northern Plains. Dewpoints into the 70s F, beneath 8+ C/km mid-level lapse rates, will support strong to locally extreme instability by afternoon peak heating. The ejection of the upper trough will provide enough upper support for scattered thunderstorm development. Increasing westerly flow with height will result in straight, elongated hodographs. Supercells should be the main mode of convection, at least initially, with severe wind and hail the primary threats. ...Days 5-6 (Friday-Saturday) - Midwest toward the Great Lakes... The main mid-level trough will continue to slowly approach the Upper MS Valley as a preceding mid-level impulse continues to advance eastward. Potential exists for renewed thunderstorm development for portions of the Upper MS Valley and Midwest on Friday, spreading east with upper trough advancement toward the Great Lakes on Saturday. Rich low-level moisture beneath steep mid-level lapse rates will promote strong instability in the warm sector, amid modest vertical wind shear. Somewhere in this region, strong to severe storms are likely, with severe wind/hail the main concerns on both Friday and Saturday. The timing and location of thunderstorm initiation will be highly dependent on the position of remnant outflow boundaries from storms during previous days. Such details are quite challenging to point out this far in advance, precluding severe probabilities at this time, though probabilities will likely be needed in future outlooks. ...Days 7-8 (Sunday-Monday) - Upper Mississippi Valley... The next in a series of mid-level troughs will traverse the north-central CONUS toward the end of the period. Medium-range guidance consensus depicts extreme instability (i.e. well over 4000 J/kg MLCAPE) preceding this trough, along with strong enough westerly mid-level flow and accompanying vertical wind shear. As such, another episode of organized severe storms is possible in the Sunday/Monday time-frame. However, given the seasonal weak forcing associated with this second low-amplitude trough, run-to-run guidance consistency is desired before severe probabilities are delineated. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0342 AM CDT Mon Jul 07 2025 Valid 101200Z - 151200Z ...DISCUSSION... The Southwest upper ridge will gradually flatten as a more progressive mid-level flow regime becomes established over the northern CONUS later this week into early next week. Multiple pronounced mid-level troughs, with cooler temperatures aloft, will traverse the north-central U.S. and overspread rich low-level moisture. Strong buoyancy will precede these troughs, and upon lifting of this unstable airmass, at least scattered organized thunderstorm development should ensue, with multiple rounds of strong to severe storms possible. ...Day 4 (Thursday) - Northern Plains... The first in a series of mid-level troughs will eject into the northern Plains on Day 4/Thursday, encouraging surface lee troughing across the central and northern Plains. Dewpoints into the 70s F, beneath 8+ C/km mid-level lapse rates, will support strong to locally extreme instability by afternoon peak heating. The ejection of the upper trough will provide enough upper support for scattered thunderstorm development. Increasing westerly flow with height will result in straight, elongated hodographs. Supercells should be the main mode of convection, at least initially, with severe wind and hail the primary threats. ...Days 5-6 (Friday-Saturday) - Midwest toward the Great Lakes... The main mid-level trough will continue to slowly approach the Upper MS Valley as a preceding mid-level impulse continues to advance eastward. Potential exists for renewed thunderstorm development for portions of the Upper MS Valley and Midwest on Friday, spreading east with upper trough advancement toward the Great Lakes on Saturday. Rich low-level moisture beneath steep mid-level lapse rates will promote strong instability in the warm sector, amid modest vertical wind shear. Somewhere in this region, strong to severe storms are likely, with severe wind/hail the main concerns on both Friday and Saturday. The timing and location of thunderstorm initiation will be highly dependent on the position of remnant outflow boundaries from storms during previous days. Such details are quite challenging to point out this far in advance, precluding severe probabilities at this time, though probabilities will likely be needed in future outlooks. ...Days 7-8 (Sunday-Monday) - Upper Mississippi Valley... The next in a series of mid-level troughs will traverse the north-central CONUS toward the end of the period. Medium-range guidance consensus depicts extreme instability (i.e. well over 4000 J/kg MLCAPE) preceding this trough, along with strong enough westerly mid-level flow and accompanying vertical wind shear. As such, another episode of organized severe storms is possible in the Sunday/Monday time-frame. However, given the seasonal weak forcing associated with this second low-amplitude trough, run-to-run guidance consistency is desired before severe probabilities are delineated. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0342 AM CDT Mon Jul 07 2025 Valid 101200Z - 151200Z ...DISCUSSION... The Southwest upper ridge will gradually flatten as a more progressive mid-level flow regime becomes established over the northern CONUS later this week into early next week. Multiple pronounced mid-level troughs, with cooler temperatures aloft, will traverse the north-central U.S. and overspread rich low-level moisture. Strong buoyancy will precede these troughs, and upon lifting of this unstable airmass, at least scattered organized thunderstorm development should ensue, with multiple rounds of strong to severe storms possible. ...Day 4 (Thursday) - Northern Plains... The first in a series of mid-level troughs will eject into the northern Plains on Day 4/Thursday, encouraging surface lee troughing across the central and northern Plains. Dewpoints into the 70s F, beneath 8+ C/km mid-level lapse rates, will support strong to locally extreme instability by afternoon peak heating. The ejection of the upper trough will provide enough upper support for scattered thunderstorm development. Increasing westerly flow with height will result in straight, elongated hodographs. Supercells should be the main mode of convection, at least initially, with severe wind and hail the primary threats. ...Days 5-6 (Friday-Saturday) - Midwest toward the Great Lakes... The main mid-level trough will continue to slowly approach the Upper MS Valley as a preceding mid-level impulse continues to advance eastward. Potential exists for renewed thunderstorm development for portions of the Upper MS Valley and Midwest on Friday, spreading east with upper trough advancement toward the Great Lakes on Saturday. Rich low-level moisture beneath steep mid-level lapse rates will promote strong instability in the warm sector, amid modest vertical wind shear. Somewhere in this region, strong to severe storms are likely, with severe wind/hail the main concerns on both Friday and Saturday. The timing and location of thunderstorm initiation will be highly dependent on the position of remnant outflow boundaries from storms during previous days. Such details are quite challenging to point out this far in advance, precluding severe probabilities at this time, though probabilities will likely be needed in future outlooks. ...Days 7-8 (Sunday-Monday) - Upper Mississippi Valley... The next in a series of mid-level troughs will traverse the north-central CONUS toward the end of the period. Medium-range guidance consensus depicts extreme instability (i.e. well over 4000 J/kg MLCAPE) preceding this trough, along with strong enough westerly mid-level flow and accompanying vertical wind shear. As such, another episode of organized severe storms is possible in the Sunday/Monday time-frame. However, given the seasonal weak forcing associated with this second low-amplitude trough, run-to-run guidance consistency is desired before severe probabilities are delineated. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0342 AM CDT Mon Jul 07 2025 Valid 101200Z - 151200Z ...DISCUSSION... The Southwest upper ridge will gradually flatten as a more progressive mid-level flow regime becomes established over the northern CONUS later this week into early next week. Multiple pronounced mid-level troughs, with cooler temperatures aloft, will traverse the north-central U.S. and overspread rich low-level moisture. Strong buoyancy will precede these troughs, and upon lifting of this unstable airmass, at least scattered organized thunderstorm development should ensue, with multiple rounds of strong to severe storms possible. ...Day 4 (Thursday) - Northern Plains... The first in a series of mid-level troughs will eject into the northern Plains on Day 4/Thursday, encouraging surface lee troughing across the central and northern Plains. Dewpoints into the 70s F, beneath 8+ C/km mid-level lapse rates, will support strong to locally extreme instability by afternoon peak heating. The ejection of the upper trough will provide enough upper support for scattered thunderstorm development. Increasing westerly flow with height will result in straight, elongated hodographs. Supercells should be the main mode of convection, at least initially, with severe wind and hail the primary threats. ...Days 5-6 (Friday-Saturday) - Midwest toward the Great Lakes... The main mid-level trough will continue to slowly approach the Upper MS Valley as a preceding mid-level impulse continues to advance eastward. Potential exists for renewed thunderstorm development for portions of the Upper MS Valley and Midwest on Friday, spreading east with upper trough advancement toward the Great Lakes on Saturday. Rich low-level moisture beneath steep mid-level lapse rates will promote strong instability in the warm sector, amid modest vertical wind shear. Somewhere in this region, strong to severe storms are likely, with severe wind/hail the main concerns on both Friday and Saturday. The timing and location of thunderstorm initiation will be highly dependent on the position of remnant outflow boundaries from storms during previous days. Such details are quite challenging to point out this far in advance, precluding severe probabilities at this time, though probabilities will likely be needed in future outlooks. ...Days 7-8 (Sunday-Monday) - Upper Mississippi Valley... The next in a series of mid-level troughs will traverse the north-central CONUS toward the end of the period. Medium-range guidance consensus depicts extreme instability (i.e. well over 4000 J/kg MLCAPE) preceding this trough, along with strong enough westerly mid-level flow and accompanying vertical wind shear. As such, another episode of organized severe storms is possible in the Sunday/Monday time-frame. However, given the seasonal weak forcing associated with this second low-amplitude trough, run-to-run guidance consistency is desired before severe probabilities are delineated. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0342 AM CDT Mon Jul 07 2025 Valid 101200Z - 151200Z ...DISCUSSION... The Southwest upper ridge will gradually flatten as a more progressive mid-level flow regime becomes established over the northern CONUS later this week into early next week. Multiple pronounced mid-level troughs, with cooler temperatures aloft, will traverse the north-central U.S. and overspread rich low-level moisture. Strong buoyancy will precede these troughs, and upon lifting of this unstable airmass, at least scattered organized thunderstorm development should ensue, with multiple rounds of strong to severe storms possible. ...Day 4 (Thursday) - Northern Plains... The first in a series of mid-level troughs will eject into the northern Plains on Day 4/Thursday, encouraging surface lee troughing across the central and northern Plains. Dewpoints into the 70s F, beneath 8+ C/km mid-level lapse rates, will support strong to locally extreme instability by afternoon peak heating. The ejection of the upper trough will provide enough upper support for scattered thunderstorm development. Increasing westerly flow with height will result in straight, elongated hodographs. Supercells should be the main mode of convection, at least initially, with severe wind and hail the primary threats. ...Days 5-6 (Friday-Saturday) - Midwest toward the Great Lakes... The main mid-level trough will continue to slowly approach the Upper MS Valley as a preceding mid-level impulse continues to advance eastward. Potential exists for renewed thunderstorm development for portions of the Upper MS Valley and Midwest on Friday, spreading east with upper trough advancement toward the Great Lakes on Saturday. Rich low-level moisture beneath steep mid-level lapse rates will promote strong instability in the warm sector, amid modest vertical wind shear. Somewhere in this region, strong to severe storms are likely, with severe wind/hail the main concerns on both Friday and Saturday. The timing and location of thunderstorm initiation will be highly dependent on the position of remnant outflow boundaries from storms during previous days. Such details are quite challenging to point out this far in advance, precluding severe probabilities at this time, though probabilities will likely be needed in future outlooks. ...Days 7-8 (Sunday-Monday) - Upper Mississippi Valley... The next in a series of mid-level troughs will traverse the north-central CONUS toward the end of the period. Medium-range guidance consensus depicts extreme instability (i.e. well over 4000 J/kg MLCAPE) preceding this trough, along with strong enough westerly mid-level flow and accompanying vertical wind shear. As such, another episode of organized severe storms is possible in the Sunday/Monday time-frame. However, given the seasonal weak forcing associated with this second low-amplitude trough, run-to-run guidance consistency is desired before severe probabilities are delineated. Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Mon Jul 07 2025 Valid 091200Z - 101200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS AND THE CAROLINAS INTO THE MID ATLANTIC... ...SUMMARY... At least isolated severe storms are possible in the northern Plains on Wednesday, with large hail the main threat, and an instance of very large hail cannot be ruled out. Isolated damaging gusts are also possible across parts of the eastern U.S. ...Synopsis... An upper ridge will persist over the Southwest as a low-amplitude mid-level trough approaches the Northeast on Wednesday. A pronounced mid-level impulse will crest the upper ridge and traverse the northern Rockies, supporting the rapid onset of surface lee troughing across the northern Plains. Here, rich low-level moisture will advect northward beneath colder temperatures aloft to support strong buoyancy amid modest vertical wind shear. At least isolated severe storms are likely. Isolated strong thunderstorms may also develop along portions of the East Coast. ...Northern Plains... A conditional severe threat is expected to develop ahead of the surface trough on Wednesday afternoon. Dewpoints into the 60s F will be overspread by 8+ C/km mid-level lapse rates by afternoon peak heating, yielding 3500-4500 J/kg MLCAPE. Modest northwesterly 500 mb flow rotating around the ridge will overspread the aforementioned southerly flow, resulting in modestly elongated hodographs and 30 kts of effective bulk shear. A dryline feature will advance eastward during the afternoon, serving as a primary lifting mechanism in tandem with strong surface heating given weak upper support. Isolated supercell development is possible, accompanied by a severe wind/hail risk. Given the degree of buoyancy in place, a conditional risk of 2+ inch hail exists should a supercell develop and become sustained. Weak upper support and lack of confidence for greater storm coverage is the primary limiting factor for higher severe probabilities at this time. ...Portions of the Carolinas into the Mid Atlantic... Scattered thunderstorms should develop atop a moist, weakly capped boundary layer by early afternoon. Though vertical wind shear should be weak and lapse rates will be poor, surface heating of the moist boundary layer will support 2000-3000 J/kg of tall/thin CAPE. As such, the stronger storms may produce wet downbursts and subsequent isolated damaging gusts. ..Squitieri.. 07/07/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Mon Jul 07 2025 Valid 091200Z - 101200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS AND THE CAROLINAS INTO THE MID ATLANTIC... ...SUMMARY... At least isolated severe storms are possible in the northern Plains on Wednesday, with large hail the main threat, and an instance of very large hail cannot be ruled out. Isolated damaging gusts are also possible across parts of the eastern U.S. ...Synopsis... An upper ridge will persist over the Southwest as a low-amplitude mid-level trough approaches the Northeast on Wednesday. A pronounced mid-level impulse will crest the upper ridge and traverse the northern Rockies, supporting the rapid onset of surface lee troughing across the northern Plains. Here, rich low-level moisture will advect northward beneath colder temperatures aloft to support strong buoyancy amid modest vertical wind shear. At least isolated severe storms are likely. Isolated strong thunderstorms may also develop along portions of the East Coast. ...Northern Plains... A conditional severe threat is expected to develop ahead of the surface trough on Wednesday afternoon. Dewpoints into the 60s F will be overspread by 8+ C/km mid-level lapse rates by afternoon peak heating, yielding 3500-4500 J/kg MLCAPE. Modest northwesterly 500 mb flow rotating around the ridge will overspread the aforementioned southerly flow, resulting in modestly elongated hodographs and 30 kts of effective bulk shear. A dryline feature will advance eastward during the afternoon, serving as a primary lifting mechanism in tandem with strong surface heating given weak upper support. Isolated supercell development is possible, accompanied by a severe wind/hail risk. Given the degree of buoyancy in place, a conditional risk of 2+ inch hail exists should a supercell develop and become sustained. Weak upper support and lack of confidence for greater storm coverage is the primary limiting factor for higher severe probabilities at this time. ...Portions of the Carolinas into the Mid Atlantic... Scattered thunderstorms should develop atop a moist, weakly capped boundary layer by early afternoon. Though vertical wind shear should be weak and lapse rates will be poor, surface heating of the moist boundary layer will support 2000-3000 J/kg of tall/thin CAPE. As such, the stronger storms may produce wet downbursts and subsequent isolated damaging gusts. ..Squitieri.. 07/07/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Mon Jul 07 2025 Valid 091200Z - 101200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS AND THE CAROLINAS INTO THE MID ATLANTIC... ...SUMMARY... At least isolated severe storms are possible in the northern Plains on Wednesday, with large hail the main threat, and an instance of very large hail cannot be ruled out. Isolated damaging gusts are also possible across parts of the eastern U.S. ...Synopsis... An upper ridge will persist over the Southwest as a low-amplitude mid-level trough approaches the Northeast on Wednesday. A pronounced mid-level impulse will crest the upper ridge and traverse the northern Rockies, supporting the rapid onset of surface lee troughing across the northern Plains. Here, rich low-level moisture will advect northward beneath colder temperatures aloft to support strong buoyancy amid modest vertical wind shear. At least isolated severe storms are likely. Isolated strong thunderstorms may also develop along portions of the East Coast. ...Northern Plains... A conditional severe threat is expected to develop ahead of the surface trough on Wednesday afternoon. Dewpoints into the 60s F will be overspread by 8+ C/km mid-level lapse rates by afternoon peak heating, yielding 3500-4500 J/kg MLCAPE. Modest northwesterly 500 mb flow rotating around the ridge will overspread the aforementioned southerly flow, resulting in modestly elongated hodographs and 30 kts of effective bulk shear. A dryline feature will advance eastward during the afternoon, serving as a primary lifting mechanism in tandem with strong surface heating given weak upper support. Isolated supercell development is possible, accompanied by a severe wind/hail risk. Given the degree of buoyancy in place, a conditional risk of 2+ inch hail exists should a supercell develop and become sustained. Weak upper support and lack of confidence for greater storm coverage is the primary limiting factor for higher severe probabilities at this time. ...Portions of the Carolinas into the Mid Atlantic... Scattered thunderstorms should develop atop a moist, weakly capped boundary layer by early afternoon. Though vertical wind shear should be weak and lapse rates will be poor, surface heating of the moist boundary layer will support 2000-3000 J/kg of tall/thin CAPE. As such, the stronger storms may produce wet downbursts and subsequent isolated damaging gusts. ..Squitieri.. 07/07/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Mon Jul 07 2025 Valid 091200Z - 101200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS AND THE CAROLINAS INTO THE MID ATLANTIC... ...SUMMARY... At least isolated severe storms are possible in the northern Plains on Wednesday, with large hail the main threat, and an instance of very large hail cannot be ruled out. Isolated damaging gusts are also possible across parts of the eastern U.S. ...Synopsis... An upper ridge will persist over the Southwest as a low-amplitude mid-level trough approaches the Northeast on Wednesday. A pronounced mid-level impulse will crest the upper ridge and traverse the northern Rockies, supporting the rapid onset of surface lee troughing across the northern Plains. Here, rich low-level moisture will advect northward beneath colder temperatures aloft to support strong buoyancy amid modest vertical wind shear. At least isolated severe storms are likely. Isolated strong thunderstorms may also develop along portions of the East Coast. ...Northern Plains... A conditional severe threat is expected to develop ahead of the surface trough on Wednesday afternoon. Dewpoints into the 60s F will be overspread by 8+ C/km mid-level lapse rates by afternoon peak heating, yielding 3500-4500 J/kg MLCAPE. Modest northwesterly 500 mb flow rotating around the ridge will overspread the aforementioned southerly flow, resulting in modestly elongated hodographs and 30 kts of effective bulk shear. A dryline feature will advance eastward during the afternoon, serving as a primary lifting mechanism in tandem with strong surface heating given weak upper support. Isolated supercell development is possible, accompanied by a severe wind/hail risk. Given the degree of buoyancy in place, a conditional risk of 2+ inch hail exists should a supercell develop and become sustained. Weak upper support and lack of confidence for greater storm coverage is the primary limiting factor for higher severe probabilities at this time. ...Portions of the Carolinas into the Mid Atlantic... Scattered thunderstorms should develop atop a moist, weakly capped boundary layer by early afternoon. Though vertical wind shear should be weak and lapse rates will be poor, surface heating of the moist boundary layer will support 2000-3000 J/kg of tall/thin CAPE. As such, the stronger storms may produce wet downbursts and subsequent isolated damaging gusts. ..Squitieri.. 07/07/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Mon Jul 07 2025 Valid 091200Z - 101200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS AND THE CAROLINAS INTO THE MID ATLANTIC... ...SUMMARY... At least isolated severe storms are possible in the northern Plains on Wednesday, with large hail the main threat, and an instance of very large hail cannot be ruled out. Isolated damaging gusts are also possible across parts of the eastern U.S. ...Synopsis... An upper ridge will persist over the Southwest as a low-amplitude mid-level trough approaches the Northeast on Wednesday. A pronounced mid-level impulse will crest the upper ridge and traverse the northern Rockies, supporting the rapid onset of surface lee troughing across the northern Plains. Here, rich low-level moisture will advect northward beneath colder temperatures aloft to support strong buoyancy amid modest vertical wind shear. At least isolated severe storms are likely. Isolated strong thunderstorms may also develop along portions of the East Coast. ...Northern Plains... A conditional severe threat is expected to develop ahead of the surface trough on Wednesday afternoon. Dewpoints into the 60s F will be overspread by 8+ C/km mid-level lapse rates by afternoon peak heating, yielding 3500-4500 J/kg MLCAPE. Modest northwesterly 500 mb flow rotating around the ridge will overspread the aforementioned southerly flow, resulting in modestly elongated hodographs and 30 kts of effective bulk shear. A dryline feature will advance eastward during the afternoon, serving as a primary lifting mechanism in tandem with strong surface heating given weak upper support. Isolated supercell development is possible, accompanied by a severe wind/hail risk. Given the degree of buoyancy in place, a conditional risk of 2+ inch hail exists should a supercell develop and become sustained. Weak upper support and lack of confidence for greater storm coverage is the primary limiting factor for higher severe probabilities at this time. ...Portions of the Carolinas into the Mid Atlantic... Scattered thunderstorms should develop atop a moist, weakly capped boundary layer by early afternoon. Though vertical wind shear should be weak and lapse rates will be poor, surface heating of the moist boundary layer will support 2000-3000 J/kg of tall/thin CAPE. As such, the stronger storms may produce wet downbursts and subsequent isolated damaging gusts. ..Squitieri.. 07/07/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Mon Jul 07 2025 Valid 091200Z - 101200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS AND THE CAROLINAS INTO THE MID ATLANTIC... ...SUMMARY... At least isolated severe storms are possible in the northern Plains on Wednesday, with large hail the main threat, and an instance of very large hail cannot be ruled out. Isolated damaging gusts are also possible across parts of the eastern U.S. ...Synopsis... An upper ridge will persist over the Southwest as a low-amplitude mid-level trough approaches the Northeast on Wednesday. A pronounced mid-level impulse will crest the upper ridge and traverse the northern Rockies, supporting the rapid onset of surface lee troughing across the northern Plains. Here, rich low-level moisture will advect northward beneath colder temperatures aloft to support strong buoyancy amid modest vertical wind shear. At least isolated severe storms are likely. Isolated strong thunderstorms may also develop along portions of the East Coast. ...Northern Plains... A conditional severe threat is expected to develop ahead of the surface trough on Wednesday afternoon. Dewpoints into the 60s F will be overspread by 8+ C/km mid-level lapse rates by afternoon peak heating, yielding 3500-4500 J/kg MLCAPE. Modest northwesterly 500 mb flow rotating around the ridge will overspread the aforementioned southerly flow, resulting in modestly elongated hodographs and 30 kts of effective bulk shear. A dryline feature will advance eastward during the afternoon, serving as a primary lifting mechanism in tandem with strong surface heating given weak upper support. Isolated supercell development is possible, accompanied by a severe wind/hail risk. Given the degree of buoyancy in place, a conditional risk of 2+ inch hail exists should a supercell develop and become sustained. Weak upper support and lack of confidence for greater storm coverage is the primary limiting factor for higher severe probabilities at this time. ...Portions of the Carolinas into the Mid Atlantic... Scattered thunderstorms should develop atop a moist, weakly capped boundary layer by early afternoon. Though vertical wind shear should be weak and lapse rates will be poor, surface heating of the moist boundary layer will support 2000-3000 J/kg of tall/thin CAPE. As such, the stronger storms may produce wet downbursts and subsequent isolated damaging gusts. ..Squitieri.. 07/07/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Mon Jul 07 2025 Valid 091200Z - 101200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS AND THE CAROLINAS INTO THE MID ATLANTIC... ...SUMMARY... At least isolated severe storms are possible in the northern Plains on Wednesday, with large hail the main threat, and an instance of very large hail cannot be ruled out. Isolated damaging gusts are also possible across parts of the eastern U.S. ...Synopsis... An upper ridge will persist over the Southwest as a low-amplitude mid-level trough approaches the Northeast on Wednesday. A pronounced mid-level impulse will crest the upper ridge and traverse the northern Rockies, supporting the rapid onset of surface lee troughing across the northern Plains. Here, rich low-level moisture will advect northward beneath colder temperatures aloft to support strong buoyancy amid modest vertical wind shear. At least isolated severe storms are likely. Isolated strong thunderstorms may also develop along portions of the East Coast. ...Northern Plains... A conditional severe threat is expected to develop ahead of the surface trough on Wednesday afternoon. Dewpoints into the 60s F will be overspread by 8+ C/km mid-level lapse rates by afternoon peak heating, yielding 3500-4500 J/kg MLCAPE. Modest northwesterly 500 mb flow rotating around the ridge will overspread the aforementioned southerly flow, resulting in modestly elongated hodographs and 30 kts of effective bulk shear. A dryline feature will advance eastward during the afternoon, serving as a primary lifting mechanism in tandem with strong surface heating given weak upper support. Isolated supercell development is possible, accompanied by a severe wind/hail risk. Given the degree of buoyancy in place, a conditional risk of 2+ inch hail exists should a supercell develop and become sustained. Weak upper support and lack of confidence for greater storm coverage is the primary limiting factor for higher severe probabilities at this time. ...Portions of the Carolinas into the Mid Atlantic... Scattered thunderstorms should develop atop a moist, weakly capped boundary layer by early afternoon. Though vertical wind shear should be weak and lapse rates will be poor, surface heating of the moist boundary layer will support 2000-3000 J/kg of tall/thin CAPE. As such, the stronger storms may produce wet downbursts and subsequent isolated damaging gusts. ..Squitieri.. 07/07/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Mon Jul 07 2025 Valid 091200Z - 101200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS AND THE CAROLINAS INTO THE MID ATLANTIC... ...SUMMARY... At least isolated severe storms are possible in the northern Plains on Wednesday, with large hail the main threat, and an instance of very large hail cannot be ruled out. Isolated damaging gusts are also possible across parts of the eastern U.S. ...Synopsis... An upper ridge will persist over the Southwest as a low-amplitude mid-level trough approaches the Northeast on Wednesday. A pronounced mid-level impulse will crest the upper ridge and traverse the northern Rockies, supporting the rapid onset of surface lee troughing across the northern Plains. Here, rich low-level moisture will advect northward beneath colder temperatures aloft to support strong buoyancy amid modest vertical wind shear. At least isolated severe storms are likely. Isolated strong thunderstorms may also develop along portions of the East Coast. ...Northern Plains... A conditional severe threat is expected to develop ahead of the surface trough on Wednesday afternoon. Dewpoints into the 60s F will be overspread by 8+ C/km mid-level lapse rates by afternoon peak heating, yielding 3500-4500 J/kg MLCAPE. Modest northwesterly 500 mb flow rotating around the ridge will overspread the aforementioned southerly flow, resulting in modestly elongated hodographs and 30 kts of effective bulk shear. A dryline feature will advance eastward during the afternoon, serving as a primary lifting mechanism in tandem with strong surface heating given weak upper support. Isolated supercell development is possible, accompanied by a severe wind/hail risk. Given the degree of buoyancy in place, a conditional risk of 2+ inch hail exists should a supercell develop and become sustained. Weak upper support and lack of confidence for greater storm coverage is the primary limiting factor for higher severe probabilities at this time. ...Portions of the Carolinas into the Mid Atlantic... Scattered thunderstorms should develop atop a moist, weakly capped boundary layer by early afternoon. Though vertical wind shear should be weak and lapse rates will be poor, surface heating of the moist boundary layer will support 2000-3000 J/kg of tall/thin CAPE. As such, the stronger storms may produce wet downbursts and subsequent isolated damaging gusts. ..Squitieri.. 07/07/2025 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 AM CDT Mon Jul 07 2025 Valid 081200Z - 091200Z ...Synopsis... A midlevel low will gradually approach the northern CA coast as it loosely phases with a stronger midlevel trough moving eastward across British Columbia on Tuesday. Large-scale ascent preceding the midlevel low will aid in isolated thunderstorm development along the higher terrain of central OR. Around 0.7 inch PW and a deeply mixed boundary layer will favor dry thunderstorms, with an associated risk of lightning-induced ignitions and strong/erratic outflow winds. At the same time, a belt of moderate-strong midlevel winds peripheral to the trough in British Columbia will cross the Cascades. This will promote dry/breezy downslope winds in the Columbia Basin, with the strongest winds expected through the Cascade Gaps. Given dry/receptive fuels, elevated fire-weather conditions are expected. Farther south, moderate deep-layer southwesterly flow ahead of the midlevel low will overspread a well-mixed boundary layer across parts of central/southern NV, where elevated to locally critical fire-weather conditions are expected. ..Weinman.. 07/07/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 AM CDT Mon Jul 07 2025 Valid 081200Z - 091200Z ...Synopsis... A midlevel low will gradually approach the northern CA coast as it loosely phases with a stronger midlevel trough moving eastward across British Columbia on Tuesday. Large-scale ascent preceding the midlevel low will aid in isolated thunderstorm development along the higher terrain of central OR. Around 0.7 inch PW and a deeply mixed boundary layer will favor dry thunderstorms, with an associated risk of lightning-induced ignitions and strong/erratic outflow winds. At the same time, a belt of moderate-strong midlevel winds peripheral to the trough in British Columbia will cross the Cascades. This will promote dry/breezy downslope winds in the Columbia Basin, with the strongest winds expected through the Cascade Gaps. Given dry/receptive fuels, elevated fire-weather conditions are expected. Farther south, moderate deep-layer southwesterly flow ahead of the midlevel low will overspread a well-mixed boundary layer across parts of central/southern NV, where elevated to locally critical fire-weather conditions are expected. ..Weinman.. 07/07/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 AM CDT Mon Jul 07 2025 Valid 081200Z - 091200Z ...Synopsis... A midlevel low will gradually approach the northern CA coast as it loosely phases with a stronger midlevel trough moving eastward across British Columbia on Tuesday. Large-scale ascent preceding the midlevel low will aid in isolated thunderstorm development along the higher terrain of central OR. Around 0.7 inch PW and a deeply mixed boundary layer will favor dry thunderstorms, with an associated risk of lightning-induced ignitions and strong/erratic outflow winds. At the same time, a belt of moderate-strong midlevel winds peripheral to the trough in British Columbia will cross the Cascades. This will promote dry/breezy downslope winds in the Columbia Basin, with the strongest winds expected through the Cascade Gaps. Given dry/receptive fuels, elevated fire-weather conditions are expected. Farther south, moderate deep-layer southwesterly flow ahead of the midlevel low will overspread a well-mixed boundary layer across parts of central/southern NV, where elevated to locally critical fire-weather conditions are expected. ..Weinman.. 07/07/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 AM CDT Mon Jul 07 2025 Valid 081200Z - 091200Z ...Synopsis... A midlevel low will gradually approach the northern CA coast as it loosely phases with a stronger midlevel trough moving eastward across British Columbia on Tuesday. Large-scale ascent preceding the midlevel low will aid in isolated thunderstorm development along the higher terrain of central OR. Around 0.7 inch PW and a deeply mixed boundary layer will favor dry thunderstorms, with an associated risk of lightning-induced ignitions and strong/erratic outflow winds. At the same time, a belt of moderate-strong midlevel winds peripheral to the trough in British Columbia will cross the Cascades. This will promote dry/breezy downslope winds in the Columbia Basin, with the strongest winds expected through the Cascade Gaps. Given dry/receptive fuels, elevated fire-weather conditions are expected. Farther south, moderate deep-layer southwesterly flow ahead of the midlevel low will overspread a well-mixed boundary layer across parts of central/southern NV, where elevated to locally critical fire-weather conditions are expected. ..Weinman.. 07/07/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 AM CDT Mon Jul 07 2025 Valid 081200Z - 091200Z ...Synopsis... A midlevel low will gradually approach the northern CA coast as it loosely phases with a stronger midlevel trough moving eastward across British Columbia on Tuesday. Large-scale ascent preceding the midlevel low will aid in isolated thunderstorm development along the higher terrain of central OR. Around 0.7 inch PW and a deeply mixed boundary layer will favor dry thunderstorms, with an associated risk of lightning-induced ignitions and strong/erratic outflow winds. At the same time, a belt of moderate-strong midlevel winds peripheral to the trough in British Columbia will cross the Cascades. This will promote dry/breezy downslope winds in the Columbia Basin, with the strongest winds expected through the Cascade Gaps. Given dry/receptive fuels, elevated fire-weather conditions are expected. Farther south, moderate deep-layer southwesterly flow ahead of the midlevel low will overspread a well-mixed boundary layer across parts of central/southern NV, where elevated to locally critical fire-weather conditions are expected. ..Weinman.. 07/07/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 AM CDT Mon Jul 07 2025 Valid 081200Z - 091200Z ...Synopsis... A midlevel low will gradually approach the northern CA coast as it loosely phases with a stronger midlevel trough moving eastward across British Columbia on Tuesday. Large-scale ascent preceding the midlevel low will aid in isolated thunderstorm development along the higher terrain of central OR. Around 0.7 inch PW and a deeply mixed boundary layer will favor dry thunderstorms, with an associated risk of lightning-induced ignitions and strong/erratic outflow winds. At the same time, a belt of moderate-strong midlevel winds peripheral to the trough in British Columbia will cross the Cascades. This will promote dry/breezy downslope winds in the Columbia Basin, with the strongest winds expected through the Cascade Gaps. Given dry/receptive fuels, elevated fire-weather conditions are expected. Farther south, moderate deep-layer southwesterly flow ahead of the midlevel low will overspread a well-mixed boundary layer across parts of central/southern NV, where elevated to locally critical fire-weather conditions are expected. ..Weinman.. 07/07/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more