Severe Storms

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0733 AM CDT Fri Aug 15 2025 Valid 151300Z - 161200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND TONIGHT FROM PARTS OF SOUTH DAKOTA INTO THE UPPER MIDWEST... ...SUMMARY... Scattered strong to severe storms are likely today and tonight over parts of the northern Plains and Upper Mississippi Valley. ...MN/IA/WI... Latest water vapor loop shows a convectively-aided shortwave trough moving across SD/NE. A cluster of intense thunderstorms has tracked across central/eastern SD overnight producing occasional wind damage (reference MCD #1949). Another small cluster of storms is over northeast NE. Both of these areas of convection are moving into a moist and potentially moderately unstable air mass, although they may take a few hours of heating to intensify further. Despite short-term uncertainty, a consensus of overnight CAM guidance depicts storms intensifying by early afternoon and tracking eastward across parts of MN, northeast IA, and western WI. Locally damaging wind gusts and hail will be possible. Have expanded the SLGT risk area slightly farther south in line with recent model solutions. ...SD/NE this afternoon/tonight... Strong heating and ample mid-level moisture will result in scattered high-based thunderstorm development across eastern WY and western NE/SD by late afternoon. This activity will track east-northeastward through the early evening into a progressively more moist and unstable air mass. The combination of improving thermodynamic environment and an intensifying nocturnal low-level jet will likely aid in thunderstorm intensification through the evening across northern NE and central SD. Damaging winds and hail will be possible. Recent HRRR/RRFS runs suggest an upscale-organizing MCS could occur after midnight, tracking into western MN. Have extended the SLGT westward to account for this scenario. ..Hart/Dean.. 08/15/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0733 AM CDT Fri Aug 15 2025 Valid 151300Z - 161200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND TONIGHT FROM PARTS OF SOUTH DAKOTA INTO THE UPPER MIDWEST... ...SUMMARY... Scattered strong to severe storms are likely today and tonight over parts of the northern Plains and Upper Mississippi Valley. ...MN/IA/WI... Latest water vapor loop shows a convectively-aided shortwave trough moving across SD/NE. A cluster of intense thunderstorms has tracked across central/eastern SD overnight producing occasional wind damage (reference MCD #1949). Another small cluster of storms is over northeast NE. Both of these areas of convection are moving into a moist and potentially moderately unstable air mass, although they may take a few hours of heating to intensify further. Despite short-term uncertainty, a consensus of overnight CAM guidance depicts storms intensifying by early afternoon and tracking eastward across parts of MN, northeast IA, and western WI. Locally damaging wind gusts and hail will be possible. Have expanded the SLGT risk area slightly farther south in line with recent model solutions. ...SD/NE this afternoon/tonight... Strong heating and ample mid-level moisture will result in scattered high-based thunderstorm development across eastern WY and western NE/SD by late afternoon. This activity will track east-northeastward through the early evening into a progressively more moist and unstable air mass. The combination of improving thermodynamic environment and an intensifying nocturnal low-level jet will likely aid in thunderstorm intensification through the evening across northern NE and central SD. Damaging winds and hail will be possible. Recent HRRR/RRFS runs suggest an upscale-organizing MCS could occur after midnight, tracking into western MN. Have extended the SLGT westward to account for this scenario. ..Hart/Dean.. 08/15/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0733 AM CDT Fri Aug 15 2025 Valid 151300Z - 161200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND TONIGHT FROM PARTS OF SOUTH DAKOTA INTO THE UPPER MIDWEST... ...SUMMARY... Scattered strong to severe storms are likely today and tonight over parts of the northern Plains and Upper Mississippi Valley. ...MN/IA/WI... Latest water vapor loop shows a convectively-aided shortwave trough moving across SD/NE. A cluster of intense thunderstorms has tracked across central/eastern SD overnight producing occasional wind damage (reference MCD #1949). Another small cluster of storms is over northeast NE. Both of these areas of convection are moving into a moist and potentially moderately unstable air mass, although they may take a few hours of heating to intensify further. Despite short-term uncertainty, a consensus of overnight CAM guidance depicts storms intensifying by early afternoon and tracking eastward across parts of MN, northeast IA, and western WI. Locally damaging wind gusts and hail will be possible. Have expanded the SLGT risk area slightly farther south in line with recent model solutions. ...SD/NE this afternoon/tonight... Strong heating and ample mid-level moisture will result in scattered high-based thunderstorm development across eastern WY and western NE/SD by late afternoon. This activity will track east-northeastward through the early evening into a progressively more moist and unstable air mass. The combination of improving thermodynamic environment and an intensifying nocturnal low-level jet will likely aid in thunderstorm intensification through the evening across northern NE and central SD. Damaging winds and hail will be possible. Recent HRRR/RRFS runs suggest an upscale-organizing MCS could occur after midnight, tracking into western MN. Have extended the SLGT westward to account for this scenario. ..Hart/Dean.. 08/15/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0733 AM CDT Fri Aug 15 2025 Valid 151300Z - 161200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND TONIGHT FROM PARTS OF SOUTH DAKOTA INTO THE UPPER MIDWEST... ...SUMMARY... Scattered strong to severe storms are likely today and tonight over parts of the northern Plains and Upper Mississippi Valley. ...MN/IA/WI... Latest water vapor loop shows a convectively-aided shortwave trough moving across SD/NE. A cluster of intense thunderstorms has tracked across central/eastern SD overnight producing occasional wind damage (reference MCD #1949). Another small cluster of storms is over northeast NE. Both of these areas of convection are moving into a moist and potentially moderately unstable air mass, although they may take a few hours of heating to intensify further. Despite short-term uncertainty, a consensus of overnight CAM guidance depicts storms intensifying by early afternoon and tracking eastward across parts of MN, northeast IA, and western WI. Locally damaging wind gusts and hail will be possible. Have expanded the SLGT risk area slightly farther south in line with recent model solutions. ...SD/NE this afternoon/tonight... Strong heating and ample mid-level moisture will result in scattered high-based thunderstorm development across eastern WY and western NE/SD by late afternoon. This activity will track east-northeastward through the early evening into a progressively more moist and unstable air mass. The combination of improving thermodynamic environment and an intensifying nocturnal low-level jet will likely aid in thunderstorm intensification through the evening across northern NE and central SD. Damaging winds and hail will be possible. Recent HRRR/RRFS runs suggest an upscale-organizing MCS could occur after midnight, tracking into western MN. Have extended the SLGT westward to account for this scenario. ..Hart/Dean.. 08/15/2025 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0344 AM CDT Fri Aug 15 2025 Valid 181200Z - 231200Z ...DISCUSSION... ...Monday/Day 4 to Wednesday/Day 6... At mid-levels, heights are forecast to rise across the north-central states on Monday and Tuesday, as west-northwesterly flow remains from parts of the northern Plains to the Eastern Seaboard. Thunderstorm development will be possible each day along parts of a front, which is forecast to be slow-moving and situated from the northern Plains east-southeastward into the southern Great Lakes. An isolated severe threat will be possible in the vicinity of the front within a moderately unstable airmass on Monday from parts of South Dakota eastward into the western Great Lakes. Storms with an isolated severe threat will again be possible on Tuesday. The greatest convective coverage is forecast to be further to the east from the southern Great Lakes into the central Appalachians. On Wednesday, isolated to scattered thunderstorms are expected over parts of the mid Mississippi and lower Ohio Valleys. In this area, large-scale ascent and deep-layer shear are forecast to be weak suggesting the potential for severe storms will remain low. ...Thursday/Day 7 and Friday/Day 8... On Thursday, a cold front is forecast to move into the northern Plains. Thunderstorm development will be possible ahead of the front along an axis of instability from parts of South Dakota into northwestern Minnesota. An isolated severe threat may develop with this activity during the afternoon and evening. The potential for isolated severe is forecast to shift southeastward into the mid Missouri upper Mississippi Valleys on Friday. However, uncertainty is low at this range in the forecast period. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0344 AM CDT Fri Aug 15 2025 Valid 181200Z - 231200Z ...DISCUSSION... ...Monday/Day 4 to Wednesday/Day 6... At mid-levels, heights are forecast to rise across the north-central states on Monday and Tuesday, as west-northwesterly flow remains from parts of the northern Plains to the Eastern Seaboard. Thunderstorm development will be possible each day along parts of a front, which is forecast to be slow-moving and situated from the northern Plains east-southeastward into the southern Great Lakes. An isolated severe threat will be possible in the vicinity of the front within a moderately unstable airmass on Monday from parts of South Dakota eastward into the western Great Lakes. Storms with an isolated severe threat will again be possible on Tuesday. The greatest convective coverage is forecast to be further to the east from the southern Great Lakes into the central Appalachians. On Wednesday, isolated to scattered thunderstorms are expected over parts of the mid Mississippi and lower Ohio Valleys. In this area, large-scale ascent and deep-layer shear are forecast to be weak suggesting the potential for severe storms will remain low. ...Thursday/Day 7 and Friday/Day 8... On Thursday, a cold front is forecast to move into the northern Plains. Thunderstorm development will be possible ahead of the front along an axis of instability from parts of South Dakota into northwestern Minnesota. An isolated severe threat may develop with this activity during the afternoon and evening. The potential for isolated severe is forecast to shift southeastward into the mid Missouri upper Mississippi Valleys on Friday. However, uncertainty is low at this range in the forecast period. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0344 AM CDT Fri Aug 15 2025 Valid 181200Z - 231200Z ...DISCUSSION... ...Monday/Day 4 to Wednesday/Day 6... At mid-levels, heights are forecast to rise across the north-central states on Monday and Tuesday, as west-northwesterly flow remains from parts of the northern Plains to the Eastern Seaboard. Thunderstorm development will be possible each day along parts of a front, which is forecast to be slow-moving and situated from the northern Plains east-southeastward into the southern Great Lakes. An isolated severe threat will be possible in the vicinity of the front within a moderately unstable airmass on Monday from parts of South Dakota eastward into the western Great Lakes. Storms with an isolated severe threat will again be possible on Tuesday. The greatest convective coverage is forecast to be further to the east from the southern Great Lakes into the central Appalachians. On Wednesday, isolated to scattered thunderstorms are expected over parts of the mid Mississippi and lower Ohio Valleys. In this area, large-scale ascent and deep-layer shear are forecast to be weak suggesting the potential for severe storms will remain low. ...Thursday/Day 7 and Friday/Day 8... On Thursday, a cold front is forecast to move into the northern Plains. Thunderstorm development will be possible ahead of the front along an axis of instability from parts of South Dakota into northwestern Minnesota. An isolated severe threat may develop with this activity during the afternoon and evening. The potential for isolated severe is forecast to shift southeastward into the mid Missouri upper Mississippi Valleys on Friday. However, uncertainty is low at this range in the forecast period. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0344 AM CDT Fri Aug 15 2025 Valid 181200Z - 231200Z ...DISCUSSION... ...Monday/Day 4 to Wednesday/Day 6... At mid-levels, heights are forecast to rise across the north-central states on Monday and Tuesday, as west-northwesterly flow remains from parts of the northern Plains to the Eastern Seaboard. Thunderstorm development will be possible each day along parts of a front, which is forecast to be slow-moving and situated from the northern Plains east-southeastward into the southern Great Lakes. An isolated severe threat will be possible in the vicinity of the front within a moderately unstable airmass on Monday from parts of South Dakota eastward into the western Great Lakes. Storms with an isolated severe threat will again be possible on Tuesday. The greatest convective coverage is forecast to be further to the east from the southern Great Lakes into the central Appalachians. On Wednesday, isolated to scattered thunderstorms are expected over parts of the mid Mississippi and lower Ohio Valleys. In this area, large-scale ascent and deep-layer shear are forecast to be weak suggesting the potential for severe storms will remain low. ...Thursday/Day 7 and Friday/Day 8... On Thursday, a cold front is forecast to move into the northern Plains. Thunderstorm development will be possible ahead of the front along an axis of instability from parts of South Dakota into northwestern Minnesota. An isolated severe threat may develop with this activity during the afternoon and evening. The potential for isolated severe is forecast to shift southeastward into the mid Missouri upper Mississippi Valleys on Friday. However, uncertainty is low at this range in the forecast period. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0344 AM CDT Fri Aug 15 2025 Valid 181200Z - 231200Z ...DISCUSSION... ...Monday/Day 4 to Wednesday/Day 6... At mid-levels, heights are forecast to rise across the north-central states on Monday and Tuesday, as west-northwesterly flow remains from parts of the northern Plains to the Eastern Seaboard. Thunderstorm development will be possible each day along parts of a front, which is forecast to be slow-moving and situated from the northern Plains east-southeastward into the southern Great Lakes. An isolated severe threat will be possible in the vicinity of the front within a moderately unstable airmass on Monday from parts of South Dakota eastward into the western Great Lakes. Storms with an isolated severe threat will again be possible on Tuesday. The greatest convective coverage is forecast to be further to the east from the southern Great Lakes into the central Appalachians. On Wednesday, isolated to scattered thunderstorms are expected over parts of the mid Mississippi and lower Ohio Valleys. In this area, large-scale ascent and deep-layer shear are forecast to be weak suggesting the potential for severe storms will remain low. ...Thursday/Day 7 and Friday/Day 8... On Thursday, a cold front is forecast to move into the northern Plains. Thunderstorm development will be possible ahead of the front along an axis of instability from parts of South Dakota into northwestern Minnesota. An isolated severe threat may develop with this activity during the afternoon and evening. The potential for isolated severe is forecast to shift southeastward into the mid Missouri upper Mississippi Valleys on Friday. However, uncertainty is low at this range in the forecast period. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0344 AM CDT Fri Aug 15 2025 Valid 181200Z - 231200Z ...DISCUSSION... ...Monday/Day 4 to Wednesday/Day 6... At mid-levels, heights are forecast to rise across the north-central states on Monday and Tuesday, as west-northwesterly flow remains from parts of the northern Plains to the Eastern Seaboard. Thunderstorm development will be possible each day along parts of a front, which is forecast to be slow-moving and situated from the northern Plains east-southeastward into the southern Great Lakes. An isolated severe threat will be possible in the vicinity of the front within a moderately unstable airmass on Monday from parts of South Dakota eastward into the western Great Lakes. Storms with an isolated severe threat will again be possible on Tuesday. The greatest convective coverage is forecast to be further to the east from the southern Great Lakes into the central Appalachians. On Wednesday, isolated to scattered thunderstorms are expected over parts of the mid Mississippi and lower Ohio Valleys. In this area, large-scale ascent and deep-layer shear are forecast to be weak suggesting the potential for severe storms will remain low. ...Thursday/Day 7 and Friday/Day 8... On Thursday, a cold front is forecast to move into the northern Plains. Thunderstorm development will be possible ahead of the front along an axis of instability from parts of South Dakota into northwestern Minnesota. An isolated severe threat may develop with this activity during the afternoon and evening. The potential for isolated severe is forecast to shift southeastward into the mid Missouri upper Mississippi Valleys on Friday. However, uncertainty is low at this range in the forecast period. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0344 AM CDT Fri Aug 15 2025 Valid 181200Z - 231200Z ...DISCUSSION... ...Monday/Day 4 to Wednesday/Day 6... At mid-levels, heights are forecast to rise across the north-central states on Monday and Tuesday, as west-northwesterly flow remains from parts of the northern Plains to the Eastern Seaboard. Thunderstorm development will be possible each day along parts of a front, which is forecast to be slow-moving and situated from the northern Plains east-southeastward into the southern Great Lakes. An isolated severe threat will be possible in the vicinity of the front within a moderately unstable airmass on Monday from parts of South Dakota eastward into the western Great Lakes. Storms with an isolated severe threat will again be possible on Tuesday. The greatest convective coverage is forecast to be further to the east from the southern Great Lakes into the central Appalachians. On Wednesday, isolated to scattered thunderstorms are expected over parts of the mid Mississippi and lower Ohio Valleys. In this area, large-scale ascent and deep-layer shear are forecast to be weak suggesting the potential for severe storms will remain low. ...Thursday/Day 7 and Friday/Day 8... On Thursday, a cold front is forecast to move into the northern Plains. Thunderstorm development will be possible ahead of the front along an axis of instability from parts of South Dakota into northwestern Minnesota. An isolated severe threat may develop with this activity during the afternoon and evening. The potential for isolated severe is forecast to shift southeastward into the mid Missouri upper Mississippi Valleys on Friday. However, uncertainty is low at this range in the forecast period. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0344 AM CDT Fri Aug 15 2025 Valid 181200Z - 231200Z ...DISCUSSION... ...Monday/Day 4 to Wednesday/Day 6... At mid-levels, heights are forecast to rise across the north-central states on Monday and Tuesday, as west-northwesterly flow remains from parts of the northern Plains to the Eastern Seaboard. Thunderstorm development will be possible each day along parts of a front, which is forecast to be slow-moving and situated from the northern Plains east-southeastward into the southern Great Lakes. An isolated severe threat will be possible in the vicinity of the front within a moderately unstable airmass on Monday from parts of South Dakota eastward into the western Great Lakes. Storms with an isolated severe threat will again be possible on Tuesday. The greatest convective coverage is forecast to be further to the east from the southern Great Lakes into the central Appalachians. On Wednesday, isolated to scattered thunderstorms are expected over parts of the mid Mississippi and lower Ohio Valleys. In this area, large-scale ascent and deep-layer shear are forecast to be weak suggesting the potential for severe storms will remain low. ...Thursday/Day 7 and Friday/Day 8... On Thursday, a cold front is forecast to move into the northern Plains. Thunderstorm development will be possible ahead of the front along an axis of instability from parts of South Dakota into northwestern Minnesota. An isolated severe threat may develop with this activity during the afternoon and evening. The potential for isolated severe is forecast to shift southeastward into the mid Missouri upper Mississippi Valleys on Friday. However, uncertainty is low at this range in the forecast period. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0344 AM CDT Fri Aug 15 2025 Valid 181200Z - 231200Z ...DISCUSSION... ...Monday/Day 4 to Wednesday/Day 6... At mid-levels, heights are forecast to rise across the north-central states on Monday and Tuesday, as west-northwesterly flow remains from parts of the northern Plains to the Eastern Seaboard. Thunderstorm development will be possible each day along parts of a front, which is forecast to be slow-moving and situated from the northern Plains east-southeastward into the southern Great Lakes. An isolated severe threat will be possible in the vicinity of the front within a moderately unstable airmass on Monday from parts of South Dakota eastward into the western Great Lakes. Storms with an isolated severe threat will again be possible on Tuesday. The greatest convective coverage is forecast to be further to the east from the southern Great Lakes into the central Appalachians. On Wednesday, isolated to scattered thunderstorms are expected over parts of the mid Mississippi and lower Ohio Valleys. In this area, large-scale ascent and deep-layer shear are forecast to be weak suggesting the potential for severe storms will remain low. ...Thursday/Day 7 and Friday/Day 8... On Thursday, a cold front is forecast to move into the northern Plains. Thunderstorm development will be possible ahead of the front along an axis of instability from parts of South Dakota into northwestern Minnesota. An isolated severe threat may develop with this activity during the afternoon and evening. The potential for isolated severe is forecast to shift southeastward into the mid Missouri upper Mississippi Valleys on Friday. However, uncertainty is low at this range in the forecast period. Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0211 AM CDT Fri Aug 15 2025 Valid 171200Z - 181200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Thunderstorms with potential for isolated severe wind gusts and hail will be possible on Sunday across parts of the northern Plains and upper Mississippi Valley. ...Northern Plains/Upper Mississippi Valley... A subtle mid-level ridge is forecast to move from the upper Mississippi Valley into the western Great Lakes region on Sunday, as mid-level flow remains west-southwesterly over the northern Plains. At the surface, a front is forecast to remain in place from Nebraska into Iowa. To the north of the boundary, easterly flow is forecast over much of the northern Plains and upper Mississippi Valley. Near the front, moderate instability is likely to develop by afternoon, and localized pockets of strong instability will be possible. As temperatures peak in the mid to late afternoon, convective initiation is expected to take place in the vicinity of the front where low-level convergence will be maximized. Although lapse rates will be steep, large-scale ascent and deep-layer shear are both forecast to be relatively weak near the front. For this reason, any severe threat that develops should remain isolated and marginal. Hail and isolated severe gusts will be the primary threats. ..Broyles.. 08/15/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0211 AM CDT Fri Aug 15 2025 Valid 171200Z - 181200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Thunderstorms with potential for isolated severe wind gusts and hail will be possible on Sunday across parts of the northern Plains and upper Mississippi Valley. ...Northern Plains/Upper Mississippi Valley... A subtle mid-level ridge is forecast to move from the upper Mississippi Valley into the western Great Lakes region on Sunday, as mid-level flow remains west-southwesterly over the northern Plains. At the surface, a front is forecast to remain in place from Nebraska into Iowa. To the north of the boundary, easterly flow is forecast over much of the northern Plains and upper Mississippi Valley. Near the front, moderate instability is likely to develop by afternoon, and localized pockets of strong instability will be possible. As temperatures peak in the mid to late afternoon, convective initiation is expected to take place in the vicinity of the front where low-level convergence will be maximized. Although lapse rates will be steep, large-scale ascent and deep-layer shear are both forecast to be relatively weak near the front. For this reason, any severe threat that develops should remain isolated and marginal. Hail and isolated severe gusts will be the primary threats. ..Broyles.. 08/15/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0211 AM CDT Fri Aug 15 2025 Valid 171200Z - 181200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Thunderstorms with potential for isolated severe wind gusts and hail will be possible on Sunday across parts of the northern Plains and upper Mississippi Valley. ...Northern Plains/Upper Mississippi Valley... A subtle mid-level ridge is forecast to move from the upper Mississippi Valley into the western Great Lakes region on Sunday, as mid-level flow remains west-southwesterly over the northern Plains. At the surface, a front is forecast to remain in place from Nebraska into Iowa. To the north of the boundary, easterly flow is forecast over much of the northern Plains and upper Mississippi Valley. Near the front, moderate instability is likely to develop by afternoon, and localized pockets of strong instability will be possible. As temperatures peak in the mid to late afternoon, convective initiation is expected to take place in the vicinity of the front where low-level convergence will be maximized. Although lapse rates will be steep, large-scale ascent and deep-layer shear are both forecast to be relatively weak near the front. For this reason, any severe threat that develops should remain isolated and marginal. Hail and isolated severe gusts will be the primary threats. ..Broyles.. 08/15/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0211 AM CDT Fri Aug 15 2025 Valid 171200Z - 181200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Thunderstorms with potential for isolated severe wind gusts and hail will be possible on Sunday across parts of the northern Plains and upper Mississippi Valley. ...Northern Plains/Upper Mississippi Valley... A subtle mid-level ridge is forecast to move from the upper Mississippi Valley into the western Great Lakes region on Sunday, as mid-level flow remains west-southwesterly over the northern Plains. At the surface, a front is forecast to remain in place from Nebraska into Iowa. To the north of the boundary, easterly flow is forecast over much of the northern Plains and upper Mississippi Valley. Near the front, moderate instability is likely to develop by afternoon, and localized pockets of strong instability will be possible. As temperatures peak in the mid to late afternoon, convective initiation is expected to take place in the vicinity of the front where low-level convergence will be maximized. Although lapse rates will be steep, large-scale ascent and deep-layer shear are both forecast to be relatively weak near the front. For this reason, any severe threat that develops should remain isolated and marginal. Hail and isolated severe gusts will be the primary threats. ..Broyles.. 08/15/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0211 AM CDT Fri Aug 15 2025 Valid 171200Z - 181200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Thunderstorms with potential for isolated severe wind gusts and hail will be possible on Sunday across parts of the northern Plains and upper Mississippi Valley. ...Northern Plains/Upper Mississippi Valley... A subtle mid-level ridge is forecast to move from the upper Mississippi Valley into the western Great Lakes region on Sunday, as mid-level flow remains west-southwesterly over the northern Plains. At the surface, a front is forecast to remain in place from Nebraska into Iowa. To the north of the boundary, easterly flow is forecast over much of the northern Plains and upper Mississippi Valley. Near the front, moderate instability is likely to develop by afternoon, and localized pockets of strong instability will be possible. As temperatures peak in the mid to late afternoon, convective initiation is expected to take place in the vicinity of the front where low-level convergence will be maximized. Although lapse rates will be steep, large-scale ascent and deep-layer shear are both forecast to be relatively weak near the front. For this reason, any severe threat that develops should remain isolated and marginal. Hail and isolated severe gusts will be the primary threats. ..Broyles.. 08/15/2025 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0211 AM CDT Fri Aug 15 2025 Valid 171200Z - 181200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Thunderstorms with potential for isolated severe wind gusts and hail will be possible on Sunday across parts of the northern Plains and upper Mississippi Valley. ...Northern Plains/Upper Mississippi Valley... A subtle mid-level ridge is forecast to move from the upper Mississippi Valley into the western Great Lakes region on Sunday, as mid-level flow remains west-southwesterly over the northern Plains. At the surface, a front is forecast to remain in place from Nebraska into Iowa. To the north of the boundary, easterly flow is forecast over much of the northern Plains and upper Mississippi Valley. Near the front, moderate instability is likely to develop by afternoon, and localized pockets of strong instability will be possible. As temperatures peak in the mid to late afternoon, convective initiation is expected to take place in the vicinity of the front where low-level convergence will be maximized. Although lapse rates will be steep, large-scale ascent and deep-layer shear are both forecast to be relatively weak near the front. For this reason, any severe threat that develops should remain isolated and marginal. Hail and isolated severe gusts will be the primary threats. ..Broyles.. 08/15/2025 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 AM CDT Fri Aug 15 2025 Valid 161200Z - 171200Z ...Synopsis... Troughing over the West will gradually intensify Friday as central US ridging also builds and gradually shifts eastward. As western US troughing deepens, southwesterly flow aloft will continue over the Great Basin and Intermountain West. A cold front will move through the Northwest, bringing showers and thunderstorms to parts of OR, WA and northern CA, while dry and breezy conditions will persist over the southern Great Basin. ...Dry Thunderstorms... Across the Northwest and central Rockies, persistent monsoon moisture will be in palace ahead of the upper trough and advancing cold front. Widespread wetting rainfall is expected across much of the Pacific Northwest west of the Cascades. To the east, diurnal heating and more modest moisture should support a relatively dry boundary layer with drier storms. isolated to scattered storms are expected along the cold front from eastern OR into western ID. While some wetting rainfall is possible, the modest moisture and faster storm speed should still support isolated dry thunder potential over the Northeast and central Rockies Friday afternoon into the early evening. ...Southern Great Basin... As the western US trough slowly deepens, southwesterly flow aloft will remain fairly modest over the West. Still, some increase is expected over portions of southern NV and western UT. While not overly strong, afternoon westerly winds near 15 mph appear possible Friday afternoon. With low RH (below 15) locally elevated fire-weather conditions will be possible for a few hours amidst dry fuels. The lack of stronger winds for now precludes elevated Highlights. ..Lyons.. 08/15/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more