Severe Storms

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Tue Mar 11 2025 Valid 111700Z - 121200Z ...CRITICAL FIRE WEATHER AREA FOR FAR SOUTHEASTERN ARIZONA INTO PORTIONS OF THE SOUTHERN HIGH PLAINS... The Elevated and Critical areas were expanded eastward over the southern Plains with this update, where the latest surface observations show an eastward extension of breezy/gusty surface winds and low RH atop increasingly receptive fuels. For additional details, see the previous discussion below. ..Weinman.. 03/11/2025 .PREV DISCUSSION... /ISSUED 0157 AM CDT Tue Mar 11 2025/ ...Synopsis... A mid-level trough will traverse the southern Rockies, encouraging surface lee troughing and associated dry downslope flow across portions of the southern High Plains today. By afternoon peak heating, sustained westerly surface winds in the 15-25 range will overlap with 5-15 percent RH and fuels receptive to wildfire spread over portions of extreme southeast Arizona into western Texas, necessitating the maintenance of Elevated and Critical highlights. Meanwhile, a surface trough and associated cold front will sweep across the Northeast today. Ahead of the cold front, southwesterly surface winds, mainly around 10 mph, will coincide with 25-40 percent RH during the afternoon. Given the marginal surface wind fields and recent rainfall, Elevated highlights have been withheld. Still, at least localized wildfire-spread potential exists where stronger wind gusts can overlap with dry fuel beds. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1129 AM CDT Tue Mar 11 2025 Valid 111700Z - 121200Z ...CRITICAL FIRE WEATHER AREA FOR FAR SOUTHEASTERN ARIZONA INTO PORTIONS OF THE SOUTHERN HIGH PLAINS... The Elevated and Critical areas were expanded eastward over the southern Plains with this update, where the latest surface observations show an eastward extension of breezy/gusty surface winds and low RH atop increasingly receptive fuels. For additional details, see the previous discussion below. ..Weinman.. 03/11/2025 .PREV DISCUSSION... /ISSUED 0157 AM CDT Tue Mar 11 2025/ ...Synopsis... A mid-level trough will traverse the southern Rockies, encouraging surface lee troughing and associated dry downslope flow across portions of the southern High Plains today. By afternoon peak heating, sustained westerly surface winds in the 15-25 range will overlap with 5-15 percent RH and fuels receptive to wildfire spread over portions of extreme southeast Arizona into western Texas, necessitating the maintenance of Elevated and Critical highlights. Meanwhile, a surface trough and associated cold front will sweep across the Northeast today. Ahead of the cold front, southwesterly surface winds, mainly around 10 mph, will coincide with 25-40 percent RH during the afternoon. Given the marginal surface wind fields and recent rainfall, Elevated highlights have been withheld. Still, at least localized wildfire-spread potential exists where stronger wind gusts can overlap with dry fuel beds. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1107 AM CDT Tue Mar 11 2025 Valid 111630Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are expected across far southern California and into Arizona today into tonight. Severe storms are not expected. ...Synopsis... Recent satellite imagery shows a well-defined upper low off the southern CA coast, with another cyclone off the Carolina coast over the western Atlantic. Modest upper ridging is in place over much of the central and eastern CONUS between these two features. The southern CA upper low is forecast to progress eastward throughout the day, devolving into an open wave as it becomes increasingly more progressive. By early Wednesday, this system is expected to be near the AZ/NM/Mexico border intersection with enhanced mid-level flow stretching through its base from the northern Baja Peninsula across northern Mexico into Far West TX. Increasing mid-level moisture will accompany this wave as it moves eastward, combining with cold temperatures aloft to support modest buoyancy from southern CA into central and southern AZ. Isolated to widely scattered thunderstorm development is possible as the large-scale forcing for ascent attendant to this wave interacts with this buoyancy. Showers and thunderstorms will likely begin across southern CA this afternoon, spreading eastward over AZ throughout the evening and overnight. Highest coverage is expected over west-central AZ. Modest buoyancy and weak vertical shear should keep the severe thunderstorm potential very low. ..Mosier/Flournoy.. 03/11/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1107 AM CDT Tue Mar 11 2025 Valid 111630Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are expected across far southern California and into Arizona today into tonight. Severe storms are not expected. ...Synopsis... Recent satellite imagery shows a well-defined upper low off the southern CA coast, with another cyclone off the Carolina coast over the western Atlantic. Modest upper ridging is in place over much of the central and eastern CONUS between these two features. The southern CA upper low is forecast to progress eastward throughout the day, devolving into an open wave as it becomes increasingly more progressive. By early Wednesday, this system is expected to be near the AZ/NM/Mexico border intersection with enhanced mid-level flow stretching through its base from the northern Baja Peninsula across northern Mexico into Far West TX. Increasing mid-level moisture will accompany this wave as it moves eastward, combining with cold temperatures aloft to support modest buoyancy from southern CA into central and southern AZ. Isolated to widely scattered thunderstorm development is possible as the large-scale forcing for ascent attendant to this wave interacts with this buoyancy. Showers and thunderstorms will likely begin across southern CA this afternoon, spreading eastward over AZ throughout the evening and overnight. Highest coverage is expected over west-central AZ. Modest buoyancy and weak vertical shear should keep the severe thunderstorm potential very low. ..Mosier/Flournoy.. 03/11/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1107 AM CDT Tue Mar 11 2025 Valid 111630Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are expected across far southern California and into Arizona today into tonight. Severe storms are not expected. ...Synopsis... Recent satellite imagery shows a well-defined upper low off the southern CA coast, with another cyclone off the Carolina coast over the western Atlantic. Modest upper ridging is in place over much of the central and eastern CONUS between these two features. The southern CA upper low is forecast to progress eastward throughout the day, devolving into an open wave as it becomes increasingly more progressive. By early Wednesday, this system is expected to be near the AZ/NM/Mexico border intersection with enhanced mid-level flow stretching through its base from the northern Baja Peninsula across northern Mexico into Far West TX. Increasing mid-level moisture will accompany this wave as it moves eastward, combining with cold temperatures aloft to support modest buoyancy from southern CA into central and southern AZ. Isolated to widely scattered thunderstorm development is possible as the large-scale forcing for ascent attendant to this wave interacts with this buoyancy. Showers and thunderstorms will likely begin across southern CA this afternoon, spreading eastward over AZ throughout the evening and overnight. Highest coverage is expected over west-central AZ. Modest buoyancy and weak vertical shear should keep the severe thunderstorm potential very low. ..Mosier/Flournoy.. 03/11/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1107 AM CDT Tue Mar 11 2025 Valid 111630Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are expected across far southern California and into Arizona today into tonight. Severe storms are not expected. ...Synopsis... Recent satellite imagery shows a well-defined upper low off the southern CA coast, with another cyclone off the Carolina coast over the western Atlantic. Modest upper ridging is in place over much of the central and eastern CONUS between these two features. The southern CA upper low is forecast to progress eastward throughout the day, devolving into an open wave as it becomes increasingly more progressive. By early Wednesday, this system is expected to be near the AZ/NM/Mexico border intersection with enhanced mid-level flow stretching through its base from the northern Baja Peninsula across northern Mexico into Far West TX. Increasing mid-level moisture will accompany this wave as it moves eastward, combining with cold temperatures aloft to support modest buoyancy from southern CA into central and southern AZ. Isolated to widely scattered thunderstorm development is possible as the large-scale forcing for ascent attendant to this wave interacts with this buoyancy. Showers and thunderstorms will likely begin across southern CA this afternoon, spreading eastward over AZ throughout the evening and overnight. Highest coverage is expected over west-central AZ. Modest buoyancy and weak vertical shear should keep the severe thunderstorm potential very low. ..Mosier/Flournoy.. 03/11/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1107 AM CDT Tue Mar 11 2025 Valid 111630Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are expected across far southern California and into Arizona today into tonight. Severe storms are not expected. ...Synopsis... Recent satellite imagery shows a well-defined upper low off the southern CA coast, with another cyclone off the Carolina coast over the western Atlantic. Modest upper ridging is in place over much of the central and eastern CONUS between these two features. The southern CA upper low is forecast to progress eastward throughout the day, devolving into an open wave as it becomes increasingly more progressive. By early Wednesday, this system is expected to be near the AZ/NM/Mexico border intersection with enhanced mid-level flow stretching through its base from the northern Baja Peninsula across northern Mexico into Far West TX. Increasing mid-level moisture will accompany this wave as it moves eastward, combining with cold temperatures aloft to support modest buoyancy from southern CA into central and southern AZ. Isolated to widely scattered thunderstorm development is possible as the large-scale forcing for ascent attendant to this wave interacts with this buoyancy. Showers and thunderstorms will likely begin across southern CA this afternoon, spreading eastward over AZ throughout the evening and overnight. Highest coverage is expected over west-central AZ. Modest buoyancy and weak vertical shear should keep the severe thunderstorm potential very low. ..Mosier/Flournoy.. 03/11/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1107 AM CDT Tue Mar 11 2025 Valid 111630Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are expected across far southern California and into Arizona today into tonight. Severe storms are not expected. ...Synopsis... Recent satellite imagery shows a well-defined upper low off the southern CA coast, with another cyclone off the Carolina coast over the western Atlantic. Modest upper ridging is in place over much of the central and eastern CONUS between these two features. The southern CA upper low is forecast to progress eastward throughout the day, devolving into an open wave as it becomes increasingly more progressive. By early Wednesday, this system is expected to be near the AZ/NM/Mexico border intersection with enhanced mid-level flow stretching through its base from the northern Baja Peninsula across northern Mexico into Far West TX. Increasing mid-level moisture will accompany this wave as it moves eastward, combining with cold temperatures aloft to support modest buoyancy from southern CA into central and southern AZ. Isolated to widely scattered thunderstorm development is possible as the large-scale forcing for ascent attendant to this wave interacts with this buoyancy. Showers and thunderstorms will likely begin across southern CA this afternoon, spreading eastward over AZ throughout the evening and overnight. Highest coverage is expected over west-central AZ. Modest buoyancy and weak vertical shear should keep the severe thunderstorm potential very low. ..Mosier/Flournoy.. 03/11/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1107 AM CDT Tue Mar 11 2025 Valid 111630Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are expected across far southern California and into Arizona today into tonight. Severe storms are not expected. ...Synopsis... Recent satellite imagery shows a well-defined upper low off the southern CA coast, with another cyclone off the Carolina coast over the western Atlantic. Modest upper ridging is in place over much of the central and eastern CONUS between these two features. The southern CA upper low is forecast to progress eastward throughout the day, devolving into an open wave as it becomes increasingly more progressive. By early Wednesday, this system is expected to be near the AZ/NM/Mexico border intersection with enhanced mid-level flow stretching through its base from the northern Baja Peninsula across northern Mexico into Far West TX. Increasing mid-level moisture will accompany this wave as it moves eastward, combining with cold temperatures aloft to support modest buoyancy from southern CA into central and southern AZ. Isolated to widely scattered thunderstorm development is possible as the large-scale forcing for ascent attendant to this wave interacts with this buoyancy. Showers and thunderstorms will likely begin across southern CA this afternoon, spreading eastward over AZ throughout the evening and overnight. Highest coverage is expected over west-central AZ. Modest buoyancy and weak vertical shear should keep the severe thunderstorm potential very low. ..Mosier/Flournoy.. 03/11/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0653 AM CDT Tue Mar 11 2025 Valid 111300Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are expected across far southern California and into Arizona today into tonight. Severe storms are not expected. ...Discussion... A potent mid to upper-level low west of southern CA will move east and evolve into an open trough and reach the AZ-NM/Sonora-Chihuahua border vicinity by early Wednesday morning. Isolated to widely scattered showers associated with the cold core will spread east during the day from southern CA into the lower CO Valley and southwest AZ, and later into the Sonoran Desert/Mogollon Rim tonight. Deeper convection near and east of the mid-level cold pocket will probably result in occasional lightning flashes. Elsewhere, quiescent conditions for thunderstorm activity will prevail. ..Smith/Dean.. 03/11/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0653 AM CDT Tue Mar 11 2025 Valid 111300Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are expected across far southern California and into Arizona today into tonight. Severe storms are not expected. ...Discussion... A potent mid to upper-level low west of southern CA will move east and evolve into an open trough and reach the AZ-NM/Sonora-Chihuahua border vicinity by early Wednesday morning. Isolated to widely scattered showers associated with the cold core will spread east during the day from southern CA into the lower CO Valley and southwest AZ, and later into the Sonoran Desert/Mogollon Rim tonight. Deeper convection near and east of the mid-level cold pocket will probably result in occasional lightning flashes. Elsewhere, quiescent conditions for thunderstorm activity will prevail. ..Smith/Dean.. 03/11/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0653 AM CDT Tue Mar 11 2025 Valid 111300Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are expected across far southern California and into Arizona today into tonight. Severe storms are not expected. ...Discussion... A potent mid to upper-level low west of southern CA will move east and evolve into an open trough and reach the AZ-NM/Sonora-Chihuahua border vicinity by early Wednesday morning. Isolated to widely scattered showers associated with the cold core will spread east during the day from southern CA into the lower CO Valley and southwest AZ, and later into the Sonoran Desert/Mogollon Rim tonight. Deeper convection near and east of the mid-level cold pocket will probably result in occasional lightning flashes. Elsewhere, quiescent conditions for thunderstorm activity will prevail. ..Smith/Dean.. 03/11/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0653 AM CDT Tue Mar 11 2025 Valid 111300Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are expected across far southern California and into Arizona today into tonight. Severe storms are not expected. ...Discussion... A potent mid to upper-level low west of southern CA will move east and evolve into an open trough and reach the AZ-NM/Sonora-Chihuahua border vicinity by early Wednesday morning. Isolated to widely scattered showers associated with the cold core will spread east during the day from southern CA into the lower CO Valley and southwest AZ, and later into the Sonoran Desert/Mogollon Rim tonight. Deeper convection near and east of the mid-level cold pocket will probably result in occasional lightning flashes. Elsewhere, quiescent conditions for thunderstorm activity will prevail. ..Smith/Dean.. 03/11/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0653 AM CDT Tue Mar 11 2025 Valid 111300Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are expected across far southern California and into Arizona today into tonight. Severe storms are not expected. ...Discussion... A potent mid to upper-level low west of southern CA will move east and evolve into an open trough and reach the AZ-NM/Sonora-Chihuahua border vicinity by early Wednesday morning. Isolated to widely scattered showers associated with the cold core will spread east during the day from southern CA into the lower CO Valley and southwest AZ, and later into the Sonoran Desert/Mogollon Rim tonight. Deeper convection near and east of the mid-level cold pocket will probably result in occasional lightning flashes. Elsewhere, quiescent conditions for thunderstorm activity will prevail. ..Smith/Dean.. 03/11/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0653 AM CDT Tue Mar 11 2025 Valid 111300Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are expected across far southern California and into Arizona today into tonight. Severe storms are not expected. ...Discussion... A potent mid to upper-level low west of southern CA will move east and evolve into an open trough and reach the AZ-NM/Sonora-Chihuahua border vicinity by early Wednesday morning. Isolated to widely scattered showers associated with the cold core will spread east during the day from southern CA into the lower CO Valley and southwest AZ, and later into the Sonoran Desert/Mogollon Rim tonight. Deeper convection near and east of the mid-level cold pocket will probably result in occasional lightning flashes. Elsewhere, quiescent conditions for thunderstorm activity will prevail. ..Smith/Dean.. 03/11/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0653 AM CDT Tue Mar 11 2025 Valid 111300Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are expected across far southern California and into Arizona today into tonight. Severe storms are not expected. ...Discussion... A potent mid to upper-level low west of southern CA will move east and evolve into an open trough and reach the AZ-NM/Sonora-Chihuahua border vicinity by early Wednesday morning. Isolated to widely scattered showers associated with the cold core will spread east during the day from southern CA into the lower CO Valley and southwest AZ, and later into the Sonoran Desert/Mogollon Rim tonight. Deeper convection near and east of the mid-level cold pocket will probably result in occasional lightning flashes. Elsewhere, quiescent conditions for thunderstorm activity will prevail. ..Smith/Dean.. 03/11/2025 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0349 AM CDT Tue Mar 11 2025 Valid 141200Z - 191200Z ...DISCUSSION... ...Days 4-6/Fri-Sun - Mid/Lower MS Valley to the Southeast and Mid-Atlantic... An intense spring storm system will deliver a multi-day severe weather episode to portions of the central and eastern U.S. beginning Friday and continuing through the weekend. All severe thunderstorm hazards are expected, including widespread damaging winds, tornadoes (some strong), and large hail. On Friday, an anomalously intense upper cyclone is forecast to deepen as it tracks northeast across the southern/central Plains to the Upper Midwest. An intense jet streak (greater than 100 kt at 500 mb) will overspread the Ozarks and Mid-MS Valley during the afternoon into the overnight hours. Likewise, a low-level jet will intensify Friday night to 65+ kt. As intense surface cyclogenesis occurs, southerly low-level flow will transport modest moisture as far north as eastern IA, southeast MN and southern WI. Deeper boundary-layer moisture will remain focused southward from the Mid-South toward the Lower MS Valley/central Gulf coast. Nevertheless, strongly forced convection within intense deep-layer flow will pose a widespread risk for severe (potentially significant severe) thunderstorm winds and tornadoes from late afternoon into the overnight hours across a large area centered on the Mid/Lower MS Valley vicinity. On Saturday, the upper cyclone over the Upper Midwest will lift northeast into Ontario, but a larger-scale upper trough will remain over the Plains. The Plains trough will intensify and spread east toward the MS/OH Valleys. This will maintain the eastward progression of a strongly forced line of convection from the Ohio Valley south/southwest into the Deep South/central Gulf coast vicinity through Saturday night. Portions of the Deep South into GA may see multiple rounds of severe convection with a mix of both supercell and QLCS storm modes potentially moving across the region, posing a concern for damaging tornadoes and swaths of severe winds. On Sunday, the system will continue to shift east, with a moist airmass and strong deep-layer flow continuing to support a line of convection producing damaging winds into the Carolinas and Mid-Atlantic vicinity. Outlook areas will continue to be refined over the coming days as key features become better resolved. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0349 AM CDT Tue Mar 11 2025 Valid 141200Z - 191200Z ...DISCUSSION... ...Days 4-6/Fri-Sun - Mid/Lower MS Valley to the Southeast and Mid-Atlantic... An intense spring storm system will deliver a multi-day severe weather episode to portions of the central and eastern U.S. beginning Friday and continuing through the weekend. All severe thunderstorm hazards are expected, including widespread damaging winds, tornadoes (some strong), and large hail. On Friday, an anomalously intense upper cyclone is forecast to deepen as it tracks northeast across the southern/central Plains to the Upper Midwest. An intense jet streak (greater than 100 kt at 500 mb) will overspread the Ozarks and Mid-MS Valley during the afternoon into the overnight hours. Likewise, a low-level jet will intensify Friday night to 65+ kt. As intense surface cyclogenesis occurs, southerly low-level flow will transport modest moisture as far north as eastern IA, southeast MN and southern WI. Deeper boundary-layer moisture will remain focused southward from the Mid-South toward the Lower MS Valley/central Gulf coast. Nevertheless, strongly forced convection within intense deep-layer flow will pose a widespread risk for severe (potentially significant severe) thunderstorm winds and tornadoes from late afternoon into the overnight hours across a large area centered on the Mid/Lower MS Valley vicinity. On Saturday, the upper cyclone over the Upper Midwest will lift northeast into Ontario, but a larger-scale upper trough will remain over the Plains. The Plains trough will intensify and spread east toward the MS/OH Valleys. This will maintain the eastward progression of a strongly forced line of convection from the Ohio Valley south/southwest into the Deep South/central Gulf coast vicinity through Saturday night. Portions of the Deep South into GA may see multiple rounds of severe convection with a mix of both supercell and QLCS storm modes potentially moving across the region, posing a concern for damaging tornadoes and swaths of severe winds. On Sunday, the system will continue to shift east, with a moist airmass and strong deep-layer flow continuing to support a line of convection producing damaging winds into the Carolinas and Mid-Atlantic vicinity. Outlook areas will continue to be refined over the coming days as key features become better resolved. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0349 AM CDT Tue Mar 11 2025 Valid 141200Z - 191200Z ...DISCUSSION... ...Days 4-6/Fri-Sun - Mid/Lower MS Valley to the Southeast and Mid-Atlantic... An intense spring storm system will deliver a multi-day severe weather episode to portions of the central and eastern U.S. beginning Friday and continuing through the weekend. All severe thunderstorm hazards are expected, including widespread damaging winds, tornadoes (some strong), and large hail. On Friday, an anomalously intense upper cyclone is forecast to deepen as it tracks northeast across the southern/central Plains to the Upper Midwest. An intense jet streak (greater than 100 kt at 500 mb) will overspread the Ozarks and Mid-MS Valley during the afternoon into the overnight hours. Likewise, a low-level jet will intensify Friday night to 65+ kt. As intense surface cyclogenesis occurs, southerly low-level flow will transport modest moisture as far north as eastern IA, southeast MN and southern WI. Deeper boundary-layer moisture will remain focused southward from the Mid-South toward the Lower MS Valley/central Gulf coast. Nevertheless, strongly forced convection within intense deep-layer flow will pose a widespread risk for severe (potentially significant severe) thunderstorm winds and tornadoes from late afternoon into the overnight hours across a large area centered on the Mid/Lower MS Valley vicinity. On Saturday, the upper cyclone over the Upper Midwest will lift northeast into Ontario, but a larger-scale upper trough will remain over the Plains. The Plains trough will intensify and spread east toward the MS/OH Valleys. This will maintain the eastward progression of a strongly forced line of convection from the Ohio Valley south/southwest into the Deep South/central Gulf coast vicinity through Saturday night. Portions of the Deep South into GA may see multiple rounds of severe convection with a mix of both supercell and QLCS storm modes potentially moving across the region, posing a concern for damaging tornadoes and swaths of severe winds. On Sunday, the system will continue to shift east, with a moist airmass and strong deep-layer flow continuing to support a line of convection producing damaging winds into the Carolinas and Mid-Atlantic vicinity. Outlook areas will continue to be refined over the coming days as key features become better resolved. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0349 AM CDT Tue Mar 11 2025 Valid 141200Z - 191200Z ...DISCUSSION... ...Days 4-6/Fri-Sun - Mid/Lower MS Valley to the Southeast and Mid-Atlantic... An intense spring storm system will deliver a multi-day severe weather episode to portions of the central and eastern U.S. beginning Friday and continuing through the weekend. All severe thunderstorm hazards are expected, including widespread damaging winds, tornadoes (some strong), and large hail. On Friday, an anomalously intense upper cyclone is forecast to deepen as it tracks northeast across the southern/central Plains to the Upper Midwest. An intense jet streak (greater than 100 kt at 500 mb) will overspread the Ozarks and Mid-MS Valley during the afternoon into the overnight hours. Likewise, a low-level jet will intensify Friday night to 65+ kt. As intense surface cyclogenesis occurs, southerly low-level flow will transport modest moisture as far north as eastern IA, southeast MN and southern WI. Deeper boundary-layer moisture will remain focused southward from the Mid-South toward the Lower MS Valley/central Gulf coast. Nevertheless, strongly forced convection within intense deep-layer flow will pose a widespread risk for severe (potentially significant severe) thunderstorm winds and tornadoes from late afternoon into the overnight hours across a large area centered on the Mid/Lower MS Valley vicinity. On Saturday, the upper cyclone over the Upper Midwest will lift northeast into Ontario, but a larger-scale upper trough will remain over the Plains. The Plains trough will intensify and spread east toward the MS/OH Valleys. This will maintain the eastward progression of a strongly forced line of convection from the Ohio Valley south/southwest into the Deep South/central Gulf coast vicinity through Saturday night. Portions of the Deep South into GA may see multiple rounds of severe convection with a mix of both supercell and QLCS storm modes potentially moving across the region, posing a concern for damaging tornadoes and swaths of severe winds. On Sunday, the system will continue to shift east, with a moist airmass and strong deep-layer flow continuing to support a line of convection producing damaging winds into the Carolinas and Mid-Atlantic vicinity. Outlook areas will continue to be refined over the coming days as key features become better resolved. Read more