Severe Storms

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0222 AM CDT Sun Aug 17 2025 Valid 191200Z - 201200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A severe threat is not expected to develop across the continental U.S. on Tuesday or Tuesday night. ...DISCUSSION... A mid-level ridge is forecast to build over the central Rockies and northern High Plains on Tuesday. At the surface, a post-frontal airmass will likely be located across the upper Mississippi Valley. Along the southern and western periphery of the post-frontal airmass, moderate instability is expected to develop by afternoon from parts of the central Plains eastward into the lower Ohio Valley. Near the instability axis, a convective cluster appears likely over part of Kansas Tuesday afternoon. The storms are not expected to be severe due to weak deep-layer shear and limited large-scale ascent. Isolated thunderstorms may also develop over parts of the mid Mississippi and lower Ohio Valleys in the afternoon. These storms are also not expected to be severe for similar reasons. ...Synopsis... ..Broyles.. 08/17/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0222 AM CDT Sun Aug 17 2025 Valid 191200Z - 201200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A severe threat is not expected to develop across the continental U.S. on Tuesday or Tuesday night. ...DISCUSSION... A mid-level ridge is forecast to build over the central Rockies and northern High Plains on Tuesday. At the surface, a post-frontal airmass will likely be located across the upper Mississippi Valley. Along the southern and western periphery of the post-frontal airmass, moderate instability is expected to develop by afternoon from parts of the central Plains eastward into the lower Ohio Valley. Near the instability axis, a convective cluster appears likely over part of Kansas Tuesday afternoon. The storms are not expected to be severe due to weak deep-layer shear and limited large-scale ascent. Isolated thunderstorms may also develop over parts of the mid Mississippi and lower Ohio Valleys in the afternoon. These storms are also not expected to be severe for similar reasons. ...Synopsis... ..Broyles.. 08/17/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0222 AM CDT Sun Aug 17 2025 Valid 191200Z - 201200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A severe threat is not expected to develop across the continental U.S. on Tuesday or Tuesday night. ...DISCUSSION... A mid-level ridge is forecast to build over the central Rockies and northern High Plains on Tuesday. At the surface, a post-frontal airmass will likely be located across the upper Mississippi Valley. Along the southern and western periphery of the post-frontal airmass, moderate instability is expected to develop by afternoon from parts of the central Plains eastward into the lower Ohio Valley. Near the instability axis, a convective cluster appears likely over part of Kansas Tuesday afternoon. The storms are not expected to be severe due to weak deep-layer shear and limited large-scale ascent. Isolated thunderstorms may also develop over parts of the mid Mississippi and lower Ohio Valleys in the afternoon. These storms are also not expected to be severe for similar reasons. ...Synopsis... ..Broyles.. 08/17/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0222 AM CDT Sun Aug 17 2025 Valid 191200Z - 201200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A severe threat is not expected to develop across the continental U.S. on Tuesday or Tuesday night. ...DISCUSSION... A mid-level ridge is forecast to build over the central Rockies and northern High Plains on Tuesday. At the surface, a post-frontal airmass will likely be located across the upper Mississippi Valley. Along the southern and western periphery of the post-frontal airmass, moderate instability is expected to develop by afternoon from parts of the central Plains eastward into the lower Ohio Valley. Near the instability axis, a convective cluster appears likely over part of Kansas Tuesday afternoon. The storms are not expected to be severe due to weak deep-layer shear and limited large-scale ascent. Isolated thunderstorms may also develop over parts of the mid Mississippi and lower Ohio Valleys in the afternoon. These storms are also not expected to be severe for similar reasons. ...Synopsis... ..Broyles.. 08/17/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0222 AM CDT Sun Aug 17 2025 Valid 191200Z - 201200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A severe threat is not expected to develop across the continental U.S. on Tuesday or Tuesday night. ...DISCUSSION... A mid-level ridge is forecast to build over the central Rockies and northern High Plains on Tuesday. At the surface, a post-frontal airmass will likely be located across the upper Mississippi Valley. Along the southern and western periphery of the post-frontal airmass, moderate instability is expected to develop by afternoon from parts of the central Plains eastward into the lower Ohio Valley. Near the instability axis, a convective cluster appears likely over part of Kansas Tuesday afternoon. The storms are not expected to be severe due to weak deep-layer shear and limited large-scale ascent. Isolated thunderstorms may also develop over parts of the mid Mississippi and lower Ohio Valleys in the afternoon. These storms are also not expected to be severe for similar reasons. ...Synopsis... ..Broyles.. 08/17/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0222 AM CDT Sun Aug 17 2025 Valid 191200Z - 201200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A severe threat is not expected to develop across the continental U.S. on Tuesday or Tuesday night. ...DISCUSSION... A mid-level ridge is forecast to build over the central Rockies and northern High Plains on Tuesday. At the surface, a post-frontal airmass will likely be located across the upper Mississippi Valley. Along the southern and western periphery of the post-frontal airmass, moderate instability is expected to develop by afternoon from parts of the central Plains eastward into the lower Ohio Valley. Near the instability axis, a convective cluster appears likely over part of Kansas Tuesday afternoon. The storms are not expected to be severe due to weak deep-layer shear and limited large-scale ascent. Isolated thunderstorms may also develop over parts of the mid Mississippi and lower Ohio Valleys in the afternoon. These storms are also not expected to be severe for similar reasons. ...Synopsis... ..Broyles.. 08/17/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0222 AM CDT Sun Aug 17 2025 Valid 191200Z - 201200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A severe threat is not expected to develop across the continental U.S. on Tuesday or Tuesday night. ...DISCUSSION... A mid-level ridge is forecast to build over the central Rockies and northern High Plains on Tuesday. At the surface, a post-frontal airmass will likely be located across the upper Mississippi Valley. Along the southern and western periphery of the post-frontal airmass, moderate instability is expected to develop by afternoon from parts of the central Plains eastward into the lower Ohio Valley. Near the instability axis, a convective cluster appears likely over part of Kansas Tuesday afternoon. The storms are not expected to be severe due to weak deep-layer shear and limited large-scale ascent. Isolated thunderstorms may also develop over parts of the mid Mississippi and lower Ohio Valleys in the afternoon. These storms are also not expected to be severe for similar reasons. ...Synopsis... ..Broyles.. 08/17/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0222 AM CDT Sun Aug 17 2025 Valid 191200Z - 201200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A severe threat is not expected to develop across the continental U.S. on Tuesday or Tuesday night. ...DISCUSSION... A mid-level ridge is forecast to build over the central Rockies and northern High Plains on Tuesday. At the surface, a post-frontal airmass will likely be located across the upper Mississippi Valley. Along the southern and western periphery of the post-frontal airmass, moderate instability is expected to develop by afternoon from parts of the central Plains eastward into the lower Ohio Valley. Near the instability axis, a convective cluster appears likely over part of Kansas Tuesday afternoon. The storms are not expected to be severe due to weak deep-layer shear and limited large-scale ascent. Isolated thunderstorms may also develop over parts of the mid Mississippi and lower Ohio Valleys in the afternoon. These storms are also not expected to be severe for similar reasons. ...Synopsis... ..Broyles.. 08/17/2025 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0201 AM CDT Sun Aug 17 2025 Valid 181200Z - 191200Z ...NO CRITICAL AREAS... ...Synopsis... Mid-level ridging will rapidly build over the central and western US Monday as Northwest troughing continues. Above normal temperatures are expected along with a temporary decrease in monsoon moisture over much of the West. While the ridge expands, the majority of the stronger westerly flow will be shunted northward, poorly overlapping with the expected dry conditions. With weaker flow aloft, surface winds are expected to be relatively benign, limiting fire-weather potential. Still, very hot and dry conditions are expected, which could exacerbate ongoing fires locally. Additionally, a few thunderstorms remain possible over parts of eastern ID and western MT near the periphery of the ridge. While some dry lightning strikes are possible in receptive fuels, wetting rainfall and the more limited storm coverage appear unlikely to warrant 10% IsoDryT coverage. ..Lyons.. 08/17/2025 ...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 0201 AM CDT Sun Aug 17 2025 Valid 181200Z - 191200Z ...NO CRITICAL AREAS... ...Synopsis... Mid-level ridging will rapidly build over the central and western US Monday as Northwest troughing continues. Above normal temperatures are expected along with a temporary decrease in monsoon moisture over much of the West. While the ridge expands, the majority of the stronger westerly flow will be shunted northward, poorly overlapping with the expected dry conditions. With weaker flow aloft, surface winds are expected to be relatively benign, limiting fire-weather potential. Still, very hot and dry conditions are expected, which could exacerbate ongoing fires locally. Additionally, a few thunderstorms remain possible over parts of eastern ID and western MT near the periphery of the ridge. While some dry lightning strikes are possible in receptive fuels, wetting rainfall and the more limited storm coverage appear unlikely to warrant 10% IsoDryT coverage. ..Lyons.. 08/17/2025 ...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 0201 AM CDT Sun Aug 17 2025 Valid 181200Z - 191200Z ...NO CRITICAL AREAS... ...Synopsis... Mid-level ridging will rapidly build over the central and western US Monday as Northwest troughing continues. Above normal temperatures are expected along with a temporary decrease in monsoon moisture over much of the West. While the ridge expands, the majority of the stronger westerly flow will be shunted northward, poorly overlapping with the expected dry conditions. With weaker flow aloft, surface winds are expected to be relatively benign, limiting fire-weather potential. Still, very hot and dry conditions are expected, which could exacerbate ongoing fires locally. Additionally, a few thunderstorms remain possible over parts of eastern ID and western MT near the periphery of the ridge. While some dry lightning strikes are possible in receptive fuels, wetting rainfall and the more limited storm coverage appear unlikely to warrant 10% IsoDryT coverage. ..Lyons.. 08/17/2025 ...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 0201 AM CDT Sun Aug 17 2025 Valid 181200Z - 191200Z ...NO CRITICAL AREAS... ...Synopsis... Mid-level ridging will rapidly build over the central and western US Monday as Northwest troughing continues. Above normal temperatures are expected along with a temporary decrease in monsoon moisture over much of the West. While the ridge expands, the majority of the stronger westerly flow will be shunted northward, poorly overlapping with the expected dry conditions. With weaker flow aloft, surface winds are expected to be relatively benign, limiting fire-weather potential. Still, very hot and dry conditions are expected, which could exacerbate ongoing fires locally. Additionally, a few thunderstorms remain possible over parts of eastern ID and western MT near the periphery of the ridge. While some dry lightning strikes are possible in receptive fuels, wetting rainfall and the more limited storm coverage appear unlikely to warrant 10% IsoDryT coverage. ..Lyons.. 08/17/2025 ...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 0201 AM CDT Sun Aug 17 2025 Valid 181200Z - 191200Z ...NO CRITICAL AREAS... ...Synopsis... Mid-level ridging will rapidly build over the central and western US Monday as Northwest troughing continues. Above normal temperatures are expected along with a temporary decrease in monsoon moisture over much of the West. While the ridge expands, the majority of the stronger westerly flow will be shunted northward, poorly overlapping with the expected dry conditions. With weaker flow aloft, surface winds are expected to be relatively benign, limiting fire-weather potential. Still, very hot and dry conditions are expected, which could exacerbate ongoing fires locally. Additionally, a few thunderstorms remain possible over parts of eastern ID and western MT near the periphery of the ridge. While some dry lightning strikes are possible in receptive fuels, wetting rainfall and the more limited storm coverage appear unlikely to warrant 10% IsoDryT coverage. ..Lyons.. 08/17/2025 ...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 0201 AM CDT Sun Aug 17 2025 Valid 181200Z - 191200Z ...NO CRITICAL AREAS... ...Synopsis... Mid-level ridging will rapidly build over the central and western US Monday as Northwest troughing continues. Above normal temperatures are expected along with a temporary decrease in monsoon moisture over much of the West. While the ridge expands, the majority of the stronger westerly flow will be shunted northward, poorly overlapping with the expected dry conditions. With weaker flow aloft, surface winds are expected to be relatively benign, limiting fire-weather potential. Still, very hot and dry conditions are expected, which could exacerbate ongoing fires locally. Additionally, a few thunderstorms remain possible over parts of eastern ID and western MT near the periphery of the ridge. While some dry lightning strikes are possible in receptive fuels, wetting rainfall and the more limited storm coverage appear unlikely to warrant 10% IsoDryT coverage. ..Lyons.. 08/17/2025 ...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 0201 AM CDT Sun Aug 17 2025 Valid 181200Z - 191200Z ...NO CRITICAL AREAS... ...Synopsis... Mid-level ridging will rapidly build over the central and western US Monday as Northwest troughing continues. Above normal temperatures are expected along with a temporary decrease in monsoon moisture over much of the West. While the ridge expands, the majority of the stronger westerly flow will be shunted northward, poorly overlapping with the expected dry conditions. With weaker flow aloft, surface winds are expected to be relatively benign, limiting fire-weather potential. Still, very hot and dry conditions are expected, which could exacerbate ongoing fires locally. Additionally, a few thunderstorms remain possible over parts of eastern ID and western MT near the periphery of the ridge. While some dry lightning strikes are possible in receptive fuels, wetting rainfall and the more limited storm coverage appear unlikely to warrant 10% IsoDryT coverage. ..Lyons.. 08/17/2025 ...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 0201 AM CDT Sun Aug 17 2025 Valid 181200Z - 191200Z ...NO CRITICAL AREAS... ...Synopsis... Mid-level ridging will rapidly build over the central and western US Monday as Northwest troughing continues. Above normal temperatures are expected along with a temporary decrease in monsoon moisture over much of the West. While the ridge expands, the majority of the stronger westerly flow will be shunted northward, poorly overlapping with the expected dry conditions. With weaker flow aloft, surface winds are expected to be relatively benign, limiting fire-weather potential. Still, very hot and dry conditions are expected, which could exacerbate ongoing fires locally. Additionally, a few thunderstorms remain possible over parts of eastern ID and western MT near the periphery of the ridge. While some dry lightning strikes are possible in receptive fuels, wetting rainfall and the more limited storm coverage appear unlikely to warrant 10% IsoDryT coverage. ..Lyons.. 08/17/2025 ...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 0201 AM CDT Sun Aug 17 2025 Valid 181200Z - 191200Z ...NO CRITICAL AREAS... ...Synopsis... Mid-level ridging will rapidly build over the central and western US Monday as Northwest troughing continues. Above normal temperatures are expected along with a temporary decrease in monsoon moisture over much of the West. While the ridge expands, the majority of the stronger westerly flow will be shunted northward, poorly overlapping with the expected dry conditions. With weaker flow aloft, surface winds are expected to be relatively benign, limiting fire-weather potential. Still, very hot and dry conditions are expected, which could exacerbate ongoing fires locally. Additionally, a few thunderstorms remain possible over parts of eastern ID and western MT near the periphery of the ridge. While some dry lightning strikes are possible in receptive fuels, wetting rainfall and the more limited storm coverage appear unlikely to warrant 10% IsoDryT coverage. ..Lyons.. 08/17/2025 ...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 0201 AM CDT Sun Aug 17 2025 Valid 181200Z - 191200Z ...NO CRITICAL AREAS... ...Synopsis... Mid-level ridging will rapidly build over the central and western US Monday as Northwest troughing continues. Above normal temperatures are expected along with a temporary decrease in monsoon moisture over much of the West. While the ridge expands, the majority of the stronger westerly flow will be shunted northward, poorly overlapping with the expected dry conditions. With weaker flow aloft, surface winds are expected to be relatively benign, limiting fire-weather potential. Still, very hot and dry conditions are expected, which could exacerbate ongoing fires locally. Additionally, a few thunderstorms remain possible over parts of eastern ID and western MT near the periphery of the ridge. While some dry lightning strikes are possible in receptive fuels, wetting rainfall and the more limited storm coverage appear unlikely to warrant 10% IsoDryT coverage. ..Lyons.. 08/17/2025 ...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 0200 AM CDT Sun Aug 17 2025 Valid 171200Z - 181200Z ...Synopsis... Broad ridging is forecast to expand over the central US today and tonight as a mid-level trough strengthens over the West. Monsoon moisture will lift north ahead of the trough and surface cold front supporting scattered showers and a few dry thunderstorms. Dry and breezy conditions are also possible over parts of the Southwest. ...Dry Thunder Northern Rockies... As western US troughing gradually consolidates, stronger mid-level flow will move eastward across the northern Great Basin and Rockies. The surface cold front will impinge on the western edge of monsoon moisture over the regions supporting another day of showers and thunderstorms. With PWATs near 1 inch, a wetter storm mode is expected, along with some wetting rainfall. Still, the increased flow aloft and faster storm speeds could support a few storms with lower precipitation efficiency. With the threat for lightning overlapping with drier fuels (especially east) isolated dry thunderstorms remain possible. ...Eastern Great Basin... South of the intensifying upper trough, enhanced southwesterly flow will overspread portions of the Great Basin beneath the western fringes of the upper ridge. Very warm temperatures are expected and fuels remain very dry/receptive to spread. A modest increase in surface winds to near 15 mph is expected through the afternoon along with RH below 15%. With some record to near record high ERC values remaining across portions of the Great Basin, a few hours of Elevated fire-weather conditions are possible. ..Lyons.. 08/17/2025 ...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 0200 AM CDT Sun Aug 17 2025 Valid 171200Z - 181200Z ...Synopsis... Broad ridging is forecast to expand over the central US today and tonight as a mid-level trough strengthens over the West. Monsoon moisture will lift north ahead of the trough and surface cold front supporting scattered showers and a few dry thunderstorms. Dry and breezy conditions are also possible over parts of the Southwest. ...Dry Thunder Northern Rockies... As western US troughing gradually consolidates, stronger mid-level flow will move eastward across the northern Great Basin and Rockies. The surface cold front will impinge on the western edge of monsoon moisture over the regions supporting another day of showers and thunderstorms. With PWATs near 1 inch, a wetter storm mode is expected, along with some wetting rainfall. Still, the increased flow aloft and faster storm speeds could support a few storms with lower precipitation efficiency. With the threat for lightning overlapping with drier fuels (especially east) isolated dry thunderstorms remain possible. ...Eastern Great Basin... South of the intensifying upper trough, enhanced southwesterly flow will overspread portions of the Great Basin beneath the western fringes of the upper ridge. Very warm temperatures are expected and fuels remain very dry/receptive to spread. A modest increase in surface winds to near 15 mph is expected through the afternoon along with RH below 15%. With some record to near record high ERC values remaining across portions of the Great Basin, a few hours of Elevated fire-weather conditions are possible. ..Lyons.. 08/17/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more