Severe Storms

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1131 AM CDT Sat Aug 09 2025 Valid 091700Z - 101200Z No changes are needed to the previous D1 Fire Weather Outlook. See previous discussion below for more information. ..Thornton.. 08/09/2025 .PREV DISCUSSION... /ISSUED 0118 AM CDT Sat Aug 09 2025/ ...Synopsis... Elevated to locally critical fire weather conditions are expected across portions of the Four Corners and central Rockies this afternoon with isolated dry thunderstorms possible across parts of the Southwest. ...Four Corners/Southwest... A cold front is noted in early-morning surface observations pushing southward across the central Plains/High Plains. This front will continue southward over the next 24 hours, reaching portions of southeast NM/western TX by this evening. A gradual weakening of the lee trough is expected as this occurs, which will diminish regional winds across the region compared to previous days. However, a swath of 15-20 mph winds will likely persist this afternoon across northern AZ into southern WY where the local pressure gradient will remain somewhat robust due to a building surface high across the northern Great Basin. With widespread RH minimums in the single digits to low teens, elevated fire weather conditions will be likely. Deep mixing will promote frequent gusts between 25-35 mph along the AZ/UT border, which should result in transient critical conditions. Coverage and duration of such conditions should remain sufficiently limited to preclude higher risk highlights. Regional 00z soundings sampled around 100-250 J/kg MUCAPE atop a deep and very dry boundary layer (LCLs near 4 km). This air mass will largely remain in place through today and will support some potential for dry lightning strikes as thunderstorms develop via orographic ascent along the Mogollon Rim by late afternoon. ...Northern Rockies... The isolated dry thunderstorm risk area across the northern Rockies was removed for this forecast update. Cold mid-level temperatures in proximity to the center of a departing upper low will likely provide adequate (albeit weak) buoyancy for isolated thunderstorms across the northern Rockies this afternoon; however, recent guidance shows very limited overlap of lightning-supporting buoyancy profiles and dry fuels. Height rises/subsidence in the wake of the upper low will also limit overall thunderstorm coverage across northern WY and central MT. While a dry lightning strike or two is possible, the overall threat appears sufficiently limited to remove the risk highlights. ...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 1131 AM CDT Sat Aug 09 2025 Valid 091700Z - 101200Z No changes are needed to the previous D1 Fire Weather Outlook. See previous discussion below for more information. ..Thornton.. 08/09/2025 .PREV DISCUSSION... /ISSUED 0118 AM CDT Sat Aug 09 2025/ ...Synopsis... Elevated to locally critical fire weather conditions are expected across portions of the Four Corners and central Rockies this afternoon with isolated dry thunderstorms possible across parts of the Southwest. ...Four Corners/Southwest... A cold front is noted in early-morning surface observations pushing southward across the central Plains/High Plains. This front will continue southward over the next 24 hours, reaching portions of southeast NM/western TX by this evening. A gradual weakening of the lee trough is expected as this occurs, which will diminish regional winds across the region compared to previous days. However, a swath of 15-20 mph winds will likely persist this afternoon across northern AZ into southern WY where the local pressure gradient will remain somewhat robust due to a building surface high across the northern Great Basin. With widespread RH minimums in the single digits to low teens, elevated fire weather conditions will be likely. Deep mixing will promote frequent gusts between 25-35 mph along the AZ/UT border, which should result in transient critical conditions. Coverage and duration of such conditions should remain sufficiently limited to preclude higher risk highlights. Regional 00z soundings sampled around 100-250 J/kg MUCAPE atop a deep and very dry boundary layer (LCLs near 4 km). This air mass will largely remain in place through today and will support some potential for dry lightning strikes as thunderstorms develop via orographic ascent along the Mogollon Rim by late afternoon. ...Northern Rockies... The isolated dry thunderstorm risk area across the northern Rockies was removed for this forecast update. Cold mid-level temperatures in proximity to the center of a departing upper low will likely provide adequate (albeit weak) buoyancy for isolated thunderstorms across the northern Rockies this afternoon; however, recent guidance shows very limited overlap of lightning-supporting buoyancy profiles and dry fuels. Height rises/subsidence in the wake of the upper low will also limit overall thunderstorm coverage across northern WY and central MT. While a dry lightning strike or two is possible, the overall threat appears sufficiently limited to remove the risk highlights. ...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 1131 AM CDT Sat Aug 09 2025 Valid 091700Z - 101200Z No changes are needed to the previous D1 Fire Weather Outlook. See previous discussion below for more information. ..Thornton.. 08/09/2025 .PREV DISCUSSION... /ISSUED 0118 AM CDT Sat Aug 09 2025/ ...Synopsis... Elevated to locally critical fire weather conditions are expected across portions of the Four Corners and central Rockies this afternoon with isolated dry thunderstorms possible across parts of the Southwest. ...Four Corners/Southwest... A cold front is noted in early-morning surface observations pushing southward across the central Plains/High Plains. This front will continue southward over the next 24 hours, reaching portions of southeast NM/western TX by this evening. A gradual weakening of the lee trough is expected as this occurs, which will diminish regional winds across the region compared to previous days. However, a swath of 15-20 mph winds will likely persist this afternoon across northern AZ into southern WY where the local pressure gradient will remain somewhat robust due to a building surface high across the northern Great Basin. With widespread RH minimums in the single digits to low teens, elevated fire weather conditions will be likely. Deep mixing will promote frequent gusts between 25-35 mph along the AZ/UT border, which should result in transient critical conditions. Coverage and duration of such conditions should remain sufficiently limited to preclude higher risk highlights. Regional 00z soundings sampled around 100-250 J/kg MUCAPE atop a deep and very dry boundary layer (LCLs near 4 km). This air mass will largely remain in place through today and will support some potential for dry lightning strikes as thunderstorms develop via orographic ascent along the Mogollon Rim by late afternoon. ...Northern Rockies... The isolated dry thunderstorm risk area across the northern Rockies was removed for this forecast update. Cold mid-level temperatures in proximity to the center of a departing upper low will likely provide adequate (albeit weak) buoyancy for isolated thunderstorms across the northern Rockies this afternoon; however, recent guidance shows very limited overlap of lightning-supporting buoyancy profiles and dry fuels. Height rises/subsidence in the wake of the upper low will also limit overall thunderstorm coverage across northern WY and central MT. While a dry lightning strike or two is possible, the overall threat appears sufficiently limited to remove the risk highlights. ...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 1122 AM CDT Sat Aug 09 2025 Valid 091630Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN COLORADO ACROSS THE CENTRAL PLAINS INTO THE WESTERN GREAT LAKES REGION... ...SUMMARY... Scattered strong/severe storms are possible this afternoon and tonight from eastern Colorado eastward across the Central Plains into the western Great Lakes. Isolated damaging wind gusts are possible in southeast Arizona. ...IA/WI Vicinity... An intense small-scale MCS affected parts of eastern NE and western IA overnight and this morning. The remnants of this system are moving across eastern IA and have weakened below severe limits. This activity will likely persist eastward across WI and into parts of Upper MI through the day, but a sagging cold front ahead of the storms coupled with some cloud cover limit the confidence it can re-intensify to severe levels. Nevertheless will maintain a SLGT risk for the areas ahead of this activity. ...NE/MO/IA tonight... Substantial airmass stabilization has occurred across this area in the wake of the overnight storms. It appears likely that relatively strong heating and return of a very moist air mass will result in strong CAPE values by early evening. A strengthening low-level jet will enhance lift along the retreating outflow boundary, likely resulting in rapid thunderstorm development after 00z over northeast KS. These storms will build east-northeastward into southern IA/northern MO through the evening/night with a risk of upscale organization and damaging winds/hail. ...CO/NE/KS... Southeasterly low-level winds will help maintain a very moist/unstable air mass over eastern CO this afternoon, with dewpoints in the 60s and MLCAPE values of 2500+ J/kg. Present indications are that thunderstorms will form off the Palmer Ridge by mid-afternoon and spread eastward toward western KS this evening. Forecast soundings show an environment favorable for supercell structures. Very large hail, damaging winds, and a tornado or two are possible. This activity may persist into the night, spreading eastward across central KS. After dark, persistent southeasterly low-level winds into the foothills of central/southern CO will interact with an approaching shortwave trough to pose the risk of continued re-development of strong/severe storms, with very large hail possible. ...Southeast AZ... Considerable low/mid level moisture are present today over parts of southeast AZ and southwest NM, with dewpoints in the low 60s. Full sunshine will result in scattered afternoon thunderstorms over the higher terrain that will propagate westward during the evening. Locally damaging wind gusts are possible. ..Hart/Marsh.. 08/09/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CDT Sat Aug 09 2025 Valid 091630Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN COLORADO ACROSS THE CENTRAL PLAINS INTO THE WESTERN GREAT LAKES REGION... ...SUMMARY... Scattered strong/severe storms are possible this afternoon and tonight from eastern Colorado eastward across the Central Plains into the western Great Lakes. Isolated damaging wind gusts are possible in southeast Arizona. ...IA/WI Vicinity... An intense small-scale MCS affected parts of eastern NE and western IA overnight and this morning. The remnants of this system are moving across eastern IA and have weakened below severe limits. This activity will likely persist eastward across WI and into parts of Upper MI through the day, but a sagging cold front ahead of the storms coupled with some cloud cover limit the confidence it can re-intensify to severe levels. Nevertheless will maintain a SLGT risk for the areas ahead of this activity. ...NE/MO/IA tonight... Substantial airmass stabilization has occurred across this area in the wake of the overnight storms. It appears likely that relatively strong heating and return of a very moist air mass will result in strong CAPE values by early evening. A strengthening low-level jet will enhance lift along the retreating outflow boundary, likely resulting in rapid thunderstorm development after 00z over northeast KS. These storms will build east-northeastward into southern IA/northern MO through the evening/night with a risk of upscale organization and damaging winds/hail. ...CO/NE/KS... Southeasterly low-level winds will help maintain a very moist/unstable air mass over eastern CO this afternoon, with dewpoints in the 60s and MLCAPE values of 2500+ J/kg. Present indications are that thunderstorms will form off the Palmer Ridge by mid-afternoon and spread eastward toward western KS this evening. Forecast soundings show an environment favorable for supercell structures. Very large hail, damaging winds, and a tornado or two are possible. This activity may persist into the night, spreading eastward across central KS. After dark, persistent southeasterly low-level winds into the foothills of central/southern CO will interact with an approaching shortwave trough to pose the risk of continued re-development of strong/severe storms, with very large hail possible. ...Southeast AZ... Considerable low/mid level moisture are present today over parts of southeast AZ and southwest NM, with dewpoints in the low 60s. Full sunshine will result in scattered afternoon thunderstorms over the higher terrain that will propagate westward during the evening. Locally damaging wind gusts are possible. ..Hart/Marsh.. 08/09/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CDT Sat Aug 09 2025 Valid 091630Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN COLORADO ACROSS THE CENTRAL PLAINS INTO THE WESTERN GREAT LAKES REGION... ...SUMMARY... Scattered strong/severe storms are possible this afternoon and tonight from eastern Colorado eastward across the Central Plains into the western Great Lakes. Isolated damaging wind gusts are possible in southeast Arizona. ...IA/WI Vicinity... An intense small-scale MCS affected parts of eastern NE and western IA overnight and this morning. The remnants of this system are moving across eastern IA and have weakened below severe limits. This activity will likely persist eastward across WI and into parts of Upper MI through the day, but a sagging cold front ahead of the storms coupled with some cloud cover limit the confidence it can re-intensify to severe levels. Nevertheless will maintain a SLGT risk for the areas ahead of this activity. ...NE/MO/IA tonight... Substantial airmass stabilization has occurred across this area in the wake of the overnight storms. It appears likely that relatively strong heating and return of a very moist air mass will result in strong CAPE values by early evening. A strengthening low-level jet will enhance lift along the retreating outflow boundary, likely resulting in rapid thunderstorm development after 00z over northeast KS. These storms will build east-northeastward into southern IA/northern MO through the evening/night with a risk of upscale organization and damaging winds/hail. ...CO/NE/KS... Southeasterly low-level winds will help maintain a very moist/unstable air mass over eastern CO this afternoon, with dewpoints in the 60s and MLCAPE values of 2500+ J/kg. Present indications are that thunderstorms will form off the Palmer Ridge by mid-afternoon and spread eastward toward western KS this evening. Forecast soundings show an environment favorable for supercell structures. Very large hail, damaging winds, and a tornado or two are possible. This activity may persist into the night, spreading eastward across central KS. After dark, persistent southeasterly low-level winds into the foothills of central/southern CO will interact with an approaching shortwave trough to pose the risk of continued re-development of strong/severe storms, with very large hail possible. ...Southeast AZ... Considerable low/mid level moisture are present today over parts of southeast AZ and southwest NM, with dewpoints in the low 60s. Full sunshine will result in scattered afternoon thunderstorms over the higher terrain that will propagate westward during the evening. Locally damaging wind gusts are possible. ..Hart/Marsh.. 08/09/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CDT Sat Aug 09 2025 Valid 091630Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN COLORADO ACROSS THE CENTRAL PLAINS INTO THE WESTERN GREAT LAKES REGION... ...SUMMARY... Scattered strong/severe storms are possible this afternoon and tonight from eastern Colorado eastward across the Central Plains into the western Great Lakes. Isolated damaging wind gusts are possible in southeast Arizona. ...IA/WI Vicinity... An intense small-scale MCS affected parts of eastern NE and western IA overnight and this morning. The remnants of this system are moving across eastern IA and have weakened below severe limits. This activity will likely persist eastward across WI and into parts of Upper MI through the day, but a sagging cold front ahead of the storms coupled with some cloud cover limit the confidence it can re-intensify to severe levels. Nevertheless will maintain a SLGT risk for the areas ahead of this activity. ...NE/MO/IA tonight... Substantial airmass stabilization has occurred across this area in the wake of the overnight storms. It appears likely that relatively strong heating and return of a very moist air mass will result in strong CAPE values by early evening. A strengthening low-level jet will enhance lift along the retreating outflow boundary, likely resulting in rapid thunderstorm development after 00z over northeast KS. These storms will build east-northeastward into southern IA/northern MO through the evening/night with a risk of upscale organization and damaging winds/hail. ...CO/NE/KS... Southeasterly low-level winds will help maintain a very moist/unstable air mass over eastern CO this afternoon, with dewpoints in the 60s and MLCAPE values of 2500+ J/kg. Present indications are that thunderstorms will form off the Palmer Ridge by mid-afternoon and spread eastward toward western KS this evening. Forecast soundings show an environment favorable for supercell structures. Very large hail, damaging winds, and a tornado or two are possible. This activity may persist into the night, spreading eastward across central KS. After dark, persistent southeasterly low-level winds into the foothills of central/southern CO will interact with an approaching shortwave trough to pose the risk of continued re-development of strong/severe storms, with very large hail possible. ...Southeast AZ... Considerable low/mid level moisture are present today over parts of southeast AZ and southwest NM, with dewpoints in the low 60s. Full sunshine will result in scattered afternoon thunderstorms over the higher terrain that will propagate westward during the evening. Locally damaging wind gusts are possible. ..Hart/Marsh.. 08/09/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CDT Sat Aug 09 2025 Valid 091630Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN COLORADO ACROSS THE CENTRAL PLAINS INTO THE WESTERN GREAT LAKES REGION... ...SUMMARY... Scattered strong/severe storms are possible this afternoon and tonight from eastern Colorado eastward across the Central Plains into the western Great Lakes. Isolated damaging wind gusts are possible in southeast Arizona. ...IA/WI Vicinity... An intense small-scale MCS affected parts of eastern NE and western IA overnight and this morning. The remnants of this system are moving across eastern IA and have weakened below severe limits. This activity will likely persist eastward across WI and into parts of Upper MI through the day, but a sagging cold front ahead of the storms coupled with some cloud cover limit the confidence it can re-intensify to severe levels. Nevertheless will maintain a SLGT risk for the areas ahead of this activity. ...NE/MO/IA tonight... Substantial airmass stabilization has occurred across this area in the wake of the overnight storms. It appears likely that relatively strong heating and return of a very moist air mass will result in strong CAPE values by early evening. A strengthening low-level jet will enhance lift along the retreating outflow boundary, likely resulting in rapid thunderstorm development after 00z over northeast KS. These storms will build east-northeastward into southern IA/northern MO through the evening/night with a risk of upscale organization and damaging winds/hail. ...CO/NE/KS... Southeasterly low-level winds will help maintain a very moist/unstable air mass over eastern CO this afternoon, with dewpoints in the 60s and MLCAPE values of 2500+ J/kg. Present indications are that thunderstorms will form off the Palmer Ridge by mid-afternoon and spread eastward toward western KS this evening. Forecast soundings show an environment favorable for supercell structures. Very large hail, damaging winds, and a tornado or two are possible. This activity may persist into the night, spreading eastward across central KS. After dark, persistent southeasterly low-level winds into the foothills of central/southern CO will interact with an approaching shortwave trough to pose the risk of continued re-development of strong/severe storms, with very large hail possible. ...Southeast AZ... Considerable low/mid level moisture are present today over parts of southeast AZ and southwest NM, with dewpoints in the low 60s. Full sunshine will result in scattered afternoon thunderstorms over the higher terrain that will propagate westward during the evening. Locally damaging wind gusts are possible. ..Hart/Marsh.. 08/09/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CDT Sat Aug 09 2025 Valid 091630Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN COLORADO ACROSS THE CENTRAL PLAINS INTO THE WESTERN GREAT LAKES REGION... ...SUMMARY... Scattered strong/severe storms are possible this afternoon and tonight from eastern Colorado eastward across the Central Plains into the western Great Lakes. Isolated damaging wind gusts are possible in southeast Arizona. ...IA/WI Vicinity... An intense small-scale MCS affected parts of eastern NE and western IA overnight and this morning. The remnants of this system are moving across eastern IA and have weakened below severe limits. This activity will likely persist eastward across WI and into parts of Upper MI through the day, but a sagging cold front ahead of the storms coupled with some cloud cover limit the confidence it can re-intensify to severe levels. Nevertheless will maintain a SLGT risk for the areas ahead of this activity. ...NE/MO/IA tonight... Substantial airmass stabilization has occurred across this area in the wake of the overnight storms. It appears likely that relatively strong heating and return of a very moist air mass will result in strong CAPE values by early evening. A strengthening low-level jet will enhance lift along the retreating outflow boundary, likely resulting in rapid thunderstorm development after 00z over northeast KS. These storms will build east-northeastward into southern IA/northern MO through the evening/night with a risk of upscale organization and damaging winds/hail. ...CO/NE/KS... Southeasterly low-level winds will help maintain a very moist/unstable air mass over eastern CO this afternoon, with dewpoints in the 60s and MLCAPE values of 2500+ J/kg. Present indications are that thunderstorms will form off the Palmer Ridge by mid-afternoon and spread eastward toward western KS this evening. Forecast soundings show an environment favorable for supercell structures. Very large hail, damaging winds, and a tornado or two are possible. This activity may persist into the night, spreading eastward across central KS. After dark, persistent southeasterly low-level winds into the foothills of central/southern CO will interact with an approaching shortwave trough to pose the risk of continued re-development of strong/severe storms, with very large hail possible. ...Southeast AZ... Considerable low/mid level moisture are present today over parts of southeast AZ and southwest NM, with dewpoints in the low 60s. Full sunshine will result in scattered afternoon thunderstorms over the higher terrain that will propagate westward during the evening. Locally damaging wind gusts are possible. ..Hart/Marsh.. 08/09/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CDT Sat Aug 09 2025 Valid 091630Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN COLORADO ACROSS THE CENTRAL PLAINS INTO THE WESTERN GREAT LAKES REGION... ...SUMMARY... Scattered strong/severe storms are possible this afternoon and tonight from eastern Colorado eastward across the Central Plains into the western Great Lakes. Isolated damaging wind gusts are possible in southeast Arizona. ...IA/WI Vicinity... An intense small-scale MCS affected parts of eastern NE and western IA overnight and this morning. The remnants of this system are moving across eastern IA and have weakened below severe limits. This activity will likely persist eastward across WI and into parts of Upper MI through the day, but a sagging cold front ahead of the storms coupled with some cloud cover limit the confidence it can re-intensify to severe levels. Nevertheless will maintain a SLGT risk for the areas ahead of this activity. ...NE/MO/IA tonight... Substantial airmass stabilization has occurred across this area in the wake of the overnight storms. It appears likely that relatively strong heating and return of a very moist air mass will result in strong CAPE values by early evening. A strengthening low-level jet will enhance lift along the retreating outflow boundary, likely resulting in rapid thunderstorm development after 00z over northeast KS. These storms will build east-northeastward into southern IA/northern MO through the evening/night with a risk of upscale organization and damaging winds/hail. ...CO/NE/KS... Southeasterly low-level winds will help maintain a very moist/unstable air mass over eastern CO this afternoon, with dewpoints in the 60s and MLCAPE values of 2500+ J/kg. Present indications are that thunderstorms will form off the Palmer Ridge by mid-afternoon and spread eastward toward western KS this evening. Forecast soundings show an environment favorable for supercell structures. Very large hail, damaging winds, and a tornado or two are possible. This activity may persist into the night, spreading eastward across central KS. After dark, persistent southeasterly low-level winds into the foothills of central/southern CO will interact with an approaching shortwave trough to pose the risk of continued re-development of strong/severe storms, with very large hail possible. ...Southeast AZ... Considerable low/mid level moisture are present today over parts of southeast AZ and southwest NM, with dewpoints in the low 60s. Full sunshine will result in scattered afternoon thunderstorms over the higher terrain that will propagate westward during the evening. Locally damaging wind gusts are possible. ..Hart/Marsh.. 08/09/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CDT Sat Aug 09 2025 Valid 091630Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN COLORADO ACROSS THE CENTRAL PLAINS INTO THE WESTERN GREAT LAKES REGION... ...SUMMARY... Scattered strong/severe storms are possible this afternoon and tonight from eastern Colorado eastward across the Central Plains into the western Great Lakes. Isolated damaging wind gusts are possible in southeast Arizona. ...IA/WI Vicinity... An intense small-scale MCS affected parts of eastern NE and western IA overnight and this morning. The remnants of this system are moving across eastern IA and have weakened below severe limits. This activity will likely persist eastward across WI and into parts of Upper MI through the day, but a sagging cold front ahead of the storms coupled with some cloud cover limit the confidence it can re-intensify to severe levels. Nevertheless will maintain a SLGT risk for the areas ahead of this activity. ...NE/MO/IA tonight... Substantial airmass stabilization has occurred across this area in the wake of the overnight storms. It appears likely that relatively strong heating and return of a very moist air mass will result in strong CAPE values by early evening. A strengthening low-level jet will enhance lift along the retreating outflow boundary, likely resulting in rapid thunderstorm development after 00z over northeast KS. These storms will build east-northeastward into southern IA/northern MO through the evening/night with a risk of upscale organization and damaging winds/hail. ...CO/NE/KS... Southeasterly low-level winds will help maintain a very moist/unstable air mass over eastern CO this afternoon, with dewpoints in the 60s and MLCAPE values of 2500+ J/kg. Present indications are that thunderstorms will form off the Palmer Ridge by mid-afternoon and spread eastward toward western KS this evening. Forecast soundings show an environment favorable for supercell structures. Very large hail, damaging winds, and a tornado or two are possible. This activity may persist into the night, spreading eastward across central KS. After dark, persistent southeasterly low-level winds into the foothills of central/southern CO will interact with an approaching shortwave trough to pose the risk of continued re-development of strong/severe storms, with very large hail possible. ...Southeast AZ... Considerable low/mid level moisture are present today over parts of southeast AZ and southwest NM, with dewpoints in the low 60s. Full sunshine will result in scattered afternoon thunderstorms over the higher terrain that will propagate westward during the evening. Locally damaging wind gusts are possible. ..Hart/Marsh.. 08/09/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CDT Sat Aug 09 2025 Valid 091630Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN COLORADO ACROSS THE CENTRAL PLAINS INTO THE WESTERN GREAT LAKES REGION... ...SUMMARY... Scattered strong/severe storms are possible this afternoon and tonight from eastern Colorado eastward across the Central Plains into the western Great Lakes. Isolated damaging wind gusts are possible in southeast Arizona. ...IA/WI Vicinity... An intense small-scale MCS affected parts of eastern NE and western IA overnight and this morning. The remnants of this system are moving across eastern IA and have weakened below severe limits. This activity will likely persist eastward across WI and into parts of Upper MI through the day, but a sagging cold front ahead of the storms coupled with some cloud cover limit the confidence it can re-intensify to severe levels. Nevertheless will maintain a SLGT risk for the areas ahead of this activity. ...NE/MO/IA tonight... Substantial airmass stabilization has occurred across this area in the wake of the overnight storms. It appears likely that relatively strong heating and return of a very moist air mass will result in strong CAPE values by early evening. A strengthening low-level jet will enhance lift along the retreating outflow boundary, likely resulting in rapid thunderstorm development after 00z over northeast KS. These storms will build east-northeastward into southern IA/northern MO through the evening/night with a risk of upscale organization and damaging winds/hail. ...CO/NE/KS... Southeasterly low-level winds will help maintain a very moist/unstable air mass over eastern CO this afternoon, with dewpoints in the 60s and MLCAPE values of 2500+ J/kg. Present indications are that thunderstorms will form off the Palmer Ridge by mid-afternoon and spread eastward toward western KS this evening. Forecast soundings show an environment favorable for supercell structures. Very large hail, damaging winds, and a tornado or two are possible. This activity may persist into the night, spreading eastward across central KS. After dark, persistent southeasterly low-level winds into the foothills of central/southern CO will interact with an approaching shortwave trough to pose the risk of continued re-development of strong/severe storms, with very large hail possible. ...Southeast AZ... Considerable low/mid level moisture are present today over parts of southeast AZ and southwest NM, with dewpoints in the low 60s. Full sunshine will result in scattered afternoon thunderstorms over the higher terrain that will propagate westward during the evening. Locally damaging wind gusts are possible. ..Hart/Marsh.. 08/09/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CDT Sat Aug 09 2025 Valid 091630Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM EASTERN COLORADO ACROSS THE CENTRAL PLAINS INTO THE WESTERN GREAT LAKES REGION... ...SUMMARY... Scattered strong/severe storms are possible this afternoon and tonight from eastern Colorado eastward across the Central Plains into the western Great Lakes. Isolated damaging wind gusts are possible in southeast Arizona. ...IA/WI Vicinity... An intense small-scale MCS affected parts of eastern NE and western IA overnight and this morning. The remnants of this system are moving across eastern IA and have weakened below severe limits. This activity will likely persist eastward across WI and into parts of Upper MI through the day, but a sagging cold front ahead of the storms coupled with some cloud cover limit the confidence it can re-intensify to severe levels. Nevertheless will maintain a SLGT risk for the areas ahead of this activity. ...NE/MO/IA tonight... Substantial airmass stabilization has occurred across this area in the wake of the overnight storms. It appears likely that relatively strong heating and return of a very moist air mass will result in strong CAPE values by early evening. A strengthening low-level jet will enhance lift along the retreating outflow boundary, likely resulting in rapid thunderstorm development after 00z over northeast KS. These storms will build east-northeastward into southern IA/northern MO through the evening/night with a risk of upscale organization and damaging winds/hail. ...CO/NE/KS... Southeasterly low-level winds will help maintain a very moist/unstable air mass over eastern CO this afternoon, with dewpoints in the 60s and MLCAPE values of 2500+ J/kg. Present indications are that thunderstorms will form off the Palmer Ridge by mid-afternoon and spread eastward toward western KS this evening. Forecast soundings show an environment favorable for supercell structures. Very large hail, damaging winds, and a tornado or two are possible. This activity may persist into the night, spreading eastward across central KS. After dark, persistent southeasterly low-level winds into the foothills of central/southern CO will interact with an approaching shortwave trough to pose the risk of continued re-development of strong/severe storms, with very large hail possible. ...Southeast AZ... Considerable low/mid level moisture are present today over parts of southeast AZ and southwest NM, with dewpoints in the low 60s. Full sunshine will result in scattered afternoon thunderstorms over the higher terrain that will propagate westward during the evening. Locally damaging wind gusts are possible. ..Hart/Marsh.. 08/09/2025 Read more

MD 1912 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR PARTS OF EXTREME NORTHEAST IOWA INTO SOUTHERN AND CENTRAL WISCONSIN
Mesoscale Discussion 1912 NWS Storm Prediction Center Norman OK 1003 AM CDT Sat Aug 09 2025 Areas affected...parts of extreme northeast Iowa into southern and central Wisconsin Concerning...Severe potential...Watch possible Valid 091503Z - 091630Z Probability of Watch Issuance...40 percent SUMMARY...Scattered damaging winds gusts are possible if the ongoing storms can intensify through mid-afternoon. Convective trends are being monitored for the need of a Severe Thunderstorm Watch issuance. DISCUSSION...An elongated MCS continues to gradually progress eastward along a stationary surface frontal boundary. Small bowing segments along the IA/MN border have recently produced sub-severe winds, with the Mason City, IA ASOS recently reporting rapid surface pressure rises and a 43 kt gust. Though some anvil cirrus have overspread some of the preceding warm sector, surface temperatures are warming into the 80s F amid at least low 70s F dewpoints, yielding 1500+ J/kg MLCAPE. Despite the aforementioned buoyancy, the stronger deep-layer shear is primarily confined to the post-frontal environment, and is oriented roughly parallel to the elongated MCS leading line. As such, there are questions regarding how intense this MCS may become through mid-afternoon, with regional radar imagery showing convective outflow gradually undercutting the MCS. Nonetheless, given preceding buoyancy, it is plausible that an uptick in damaging gust potential may increase pending favorable self-organization of the MCS. Such conditions are being monitored for the subsequent need of a Severe Thunderstorm Watch issuance. ..Squitieri/Hart.. 08/09/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...GRB...MKX...DVN...ARX...DMX... LAT...LON 42579149 42649188 42769225 42919257 43009272 43139278 43259270 43529205 43849123 43819114 44698903 44738779 43958751 43058784 42778806 42578867 42508961 42579149 MOST PROBABLE PEAK WIND GUST...55-70 MPH Read more

WW 0580 Status Updates
STATUS REPORT ON WW 580 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 NW ALO TO 25 WSW MCW TO 25 E FRM. WW 580 WILL BE ALLOWED TO EXPIRE AT 091700Z. ..SQUITIERI..08/09/25 ATTN...WFO...DMX... STATUS REPORT FOR WS 580 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS IAC033-081-189-195-091700- IA . IOWA COUNTIES INCLUDED ARE CERRO GORDO HANCOCK WINNEBAGO WORTH THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 0580 Status Updates
STATUS REPORT ON WW 580 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 NW ALO TO 25 WSW MCW TO 25 E FRM. WW 580 WILL BE ALLOWED TO EXPIRE AT 091700Z. ..SQUITIERI..08/09/25 ATTN...WFO...DMX... STATUS REPORT FOR WS 580 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS IAC033-081-189-195-091700- IA . IOWA COUNTIES INCLUDED ARE CERRO GORDO HANCOCK WINNEBAGO WORTH THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 580 SEVERE TSTM IA 091105Z - 091700Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 580 NWS Storm Prediction Center Norman OK 605 AM CDT Sat Aug 9 2025 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Western and Central Iowa * Effective this Saturday morning from 605 AM until NOON CDT. * Primary threats include... Scattered damaging winds likely with isolated significant gusts to 80 mph possible Isolated large hail events to 1.5 inches in diameter possible SUMMARY...A small but intense bowing cluster should continue moving east-northeastward this morning while producing scattered to numerous severe/damaging winds. Isolated gusts up to 70-80 mph appear possible. Additional thunderstorms will also develop along a cold front across parts of western into central Iowa. This activity should also pose mainly a severe/damaging wind threat, but isolated hail may also occur. The severe thunderstorm watch area is approximately along and 50 statute miles east and west of a line from 35 miles northwest of Mason City IA to 35 miles southwest of Des Moines IA. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU0). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. Severe thunderstorms can and occasionally do produce tornadoes. && OTHER WATCH INFORMATION...CONTINUE...WW 579... AVIATION...A few severe thunderstorms with hail surface and aloft to 1.5 inches. Extreme turbulence and surface wind gusts to 70 knots. A few cumulonimbi with maximum tops to 550. Mean storm motion vector 25035. ...Gleason Read more

MD 1911 CONCERNING SEVERE THUNDERSTORM WATCH 580... FOR PORTIONS OF IA INTO SOUTHEAST MN AND FAR WEST-CENTRAL WI
Mesoscale Discussion 1911 NWS Storm Prediction Center Norman OK 0729 AM CDT Sat Aug 09 2025 Areas affected...portions of IA into southeast MN and far west-central WI Concerning...Severe Thunderstorm Watch 580... Valid 091229Z - 091430Z The severe weather threat for Severe Thunderstorm Watch 580 continues. SUMMARY...Severe thunderstorms producing damaging wind gusts will persist across portions of western into north-central Iowa this morning. DISCUSSION...Severe gusts continue with the cluster of storms ongoing across west-central IA this morning. Radar trends have shown some downward trend in velocity strength as well as a somewhat more disorganized presentation in reflectivity. Nevertheless, measured severe gusts and wind damage reports continue as convection develops northeast along/just ahead of a surface cold front. The downstream airmass remains strongly unstable, and convection will persist along the length of the surface front from west-central WI into southeast MN and northern/western IA. The core of the low-level jet remains centered just east of ongoing storms, and stronger vertical shear tends to lag behind the surface boundary. Convection along the front in MN/WI has largely been unproductive overnight. While strong to severe gusts remain possible in the short term across IA, it is unclear if severe potential and a downstream watch will be needed into MN/WI. ..Leitman.. 08/09/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...ARX...MPX...DMX...FSD...OAX... LAT...LON 42209589 43369401 44109232 44219166 44139112 43929084 43649094 42089297 41699356 41289449 41359542 41519595 41799610 42209589 MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH MOST PROBABLE PEAK WIND GUST...65-80 MPH MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0748 AM CDT Sat Aug 09 2025 Valid 091300Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE UPPER GREAT LAKES/UPPER MIDWEST...AND EASTERN COLORADO INTO FAR WESTERN KANSAS... ...SUMMARY... Multiple severe/damaging wind swaths should occur today centered on parts of Iowa, northwest Illinois, Wisconsin, and the Upper Peninsula of Michigan. Large to very large hail will be possible across parts of eastern Colorado and vicinity this afternoon and evening. ...Upper Great Lakes/Upper Midwest into the Missouri Valley... A small but intense bowing cluster has produced numerous severe gusts/damage reports (some 75+ mph) in a narrow corridor early this morning across south-central NE to western IA. This convection should continue east-northeastward across parts of central/northern IA through the rest of the morning, with an enhanced southwesterly low-level jet providing ample moist inflow. A very unstable airmass remains in place ahead of a cold front across this area, with MUCAPE around 3000-3500 J/kg. This large reservoir of buoyancy should continue to support a severe/damaging wind threat with this cluster into parts of central/northern IA for at least the next few hours. See Mesoscale Discussion 1911 for more details on the short-term severe threat associated with this bowing complex. Additional thunderstorms have developed along/near the cold front across a broader portion of the Upper Great Lakes and Upper Midwest. It still appears probable that multiple swaths of severe/damaging winds may occur through the afternoon and evening across parts of these regions as the airmass ahead of these thunderstorms gradually destabilizes. With rich low-level moisture already in place, strong to extreme instability should once again develop by this afternoon. While stronger mid-level flow and related deep-layer shear will tend to lag the cold front, they should still be sufficient to support organized convection, mainly linear clusters. Some adjustments have been made to the Slight Risk to account for the ongoing severe thunderstorms in IA, as well as additional activity forecast to occur through the afternoon and evening. The potential for additional robust convective development tonight across parts of the MO Valley remains unclear as a southerly low-level jet strengthens once again. Regardless, have maintained severe probabilities across southeast NE and vicinity for this possibility. ...Central/Southern High Plains... A cold front should become nearly stationary by this afternoon across the south-central High Plains. A favorable low-level, post-frontal regime for severe convection is expected to develop across eastern CO by late afternoon. The presence of steep mid-level lapse rates, moderate instability, and favorable deep-layer shear will likely support scattered supercells capable of large to very large hail, localized severe gusts, and possibly a tornado or two mainly this afternoon into the evening. Across the southern High Plains, high-based convection may again develop across parts of eastern NM into the OK/TX Panhandles. This activity could pose a isolated threat for severe gusts given a very well-mixed boundary layer. ..Gleason/Leitman.. 08/09/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0748 AM CDT Sat Aug 09 2025 Valid 091300Z - 101200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE UPPER GREAT LAKES/UPPER MIDWEST...AND EASTERN COLORADO INTO FAR WESTERN KANSAS... ...SUMMARY... Multiple severe/damaging wind swaths should occur today centered on parts of Iowa, northwest Illinois, Wisconsin, and the Upper Peninsula of Michigan. Large to very large hail will be possible across parts of eastern Colorado and vicinity this afternoon and evening. ...Upper Great Lakes/Upper Midwest into the Missouri Valley... A small but intense bowing cluster has produced numerous severe gusts/damage reports (some 75+ mph) in a narrow corridor early this morning across south-central NE to western IA. This convection should continue east-northeastward across parts of central/northern IA through the rest of the morning, with an enhanced southwesterly low-level jet providing ample moist inflow. A very unstable airmass remains in place ahead of a cold front across this area, with MUCAPE around 3000-3500 J/kg. This large reservoir of buoyancy should continue to support a severe/damaging wind threat with this cluster into parts of central/northern IA for at least the next few hours. See Mesoscale Discussion 1911 for more details on the short-term severe threat associated with this bowing complex. Additional thunderstorms have developed along/near the cold front across a broader portion of the Upper Great Lakes and Upper Midwest. It still appears probable that multiple swaths of severe/damaging winds may occur through the afternoon and evening across parts of these regions as the airmass ahead of these thunderstorms gradually destabilizes. With rich low-level moisture already in place, strong to extreme instability should once again develop by this afternoon. While stronger mid-level flow and related deep-layer shear will tend to lag the cold front, they should still be sufficient to support organized convection, mainly linear clusters. Some adjustments have been made to the Slight Risk to account for the ongoing severe thunderstorms in IA, as well as additional activity forecast to occur through the afternoon and evening. The potential for additional robust convective development tonight across parts of the MO Valley remains unclear as a southerly low-level jet strengthens once again. Regardless, have maintained severe probabilities across southeast NE and vicinity for this possibility. ...Central/Southern High Plains... A cold front should become nearly stationary by this afternoon across the south-central High Plains. A favorable low-level, post-frontal regime for severe convection is expected to develop across eastern CO by late afternoon. The presence of steep mid-level lapse rates, moderate instability, and favorable deep-layer shear will likely support scattered supercells capable of large to very large hail, localized severe gusts, and possibly a tornado or two mainly this afternoon into the evening. Across the southern High Plains, high-based convection may again develop across parts of eastern NM into the OK/TX Panhandles. This activity could pose a isolated threat for severe gusts given a very well-mixed boundary layer. ..Gleason/Leitman.. 08/09/2025 Read more