Severe Storms

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

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

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

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

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

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0159 AM CDT Fri Aug 15 2025 Valid 151200Z - 161200Z ...Synopsis... Broad mid-level ridging over the Central US is forecast to build today, as weak westerly flow passes over it. Weak troughing over the Great Basin will gradually shift eastward bolstering mid-level flow over the region. A weak lee low over the High Plains will support west/southwesterly winds over much of the Great Basin and Intermountain West through this afternoon. 15-20 mph gusts will overlap with very warm and dry conditions (RH below 15) from eastern NV into portions of UT, WY and ID. Several hours of elevated fire weather conditions are probable given very dry and receptive fuels. ...Dry Thunder... Weak height falls from the upper trough over the West will continue to overspread robust monsoon moisture supporting isolated thunderstorms this afternoon. Similar to previous days, a combination of steep mid-level lapse rates and modest mid-level moisture will overlap with dry boundary layer conditions and high cloud bases. This will favor dry storms with limited potential for wetting rainfall. The favorable thermodynamic conditions, coupled with 15-25 knot storm motions over top receptive fuels will continue to support dry lightning potential with these storms over the eastern Great Basin and central Rockies. ..Lyons.. 08/15/2025 ...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 0159 AM CDT Fri Aug 15 2025 Valid 151200Z - 161200Z ...Synopsis... Broad mid-level ridging over the Central US is forecast to build today, as weak westerly flow passes over it. Weak troughing over the Great Basin will gradually shift eastward bolstering mid-level flow over the region. A weak lee low over the High Plains will support west/southwesterly winds over much of the Great Basin and Intermountain West through this afternoon. 15-20 mph gusts will overlap with very warm and dry conditions (RH below 15) from eastern NV into portions of UT, WY and ID. Several hours of elevated fire weather conditions are probable given very dry and receptive fuels. ...Dry Thunder... Weak height falls from the upper trough over the West will continue to overspread robust monsoon moisture supporting isolated thunderstorms this afternoon. Similar to previous days, a combination of steep mid-level lapse rates and modest mid-level moisture will overlap with dry boundary layer conditions and high cloud bases. This will favor dry storms with limited potential for wetting rainfall. The favorable thermodynamic conditions, coupled with 15-25 knot storm motions over top receptive fuels will continue to support dry lightning potential with these storms over the eastern Great Basin and central Rockies. ..Lyons.. 08/15/2025 ...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 0159 AM CDT Fri Aug 15 2025 Valid 151200Z - 161200Z ...Synopsis... Broad mid-level ridging over the Central US is forecast to build today, as weak westerly flow passes over it. Weak troughing over the Great Basin will gradually shift eastward bolstering mid-level flow over the region. A weak lee low over the High Plains will support west/southwesterly winds over much of the Great Basin and Intermountain West through this afternoon. 15-20 mph gusts will overlap with very warm and dry conditions (RH below 15) from eastern NV into portions of UT, WY and ID. Several hours of elevated fire weather conditions are probable given very dry and receptive fuels. ...Dry Thunder... Weak height falls from the upper trough over the West will continue to overspread robust monsoon moisture supporting isolated thunderstorms this afternoon. Similar to previous days, a combination of steep mid-level lapse rates and modest mid-level moisture will overlap with dry boundary layer conditions and high cloud bases. This will favor dry storms with limited potential for wetting rainfall. The favorable thermodynamic conditions, coupled with 15-25 knot storm motions over top receptive fuels will continue to support dry lightning potential with these storms over the eastern Great Basin and central Rockies. ..Lyons.. 08/15/2025 ...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 0159 AM CDT Fri Aug 15 2025 Valid 151200Z - 161200Z ...Synopsis... Broad mid-level ridging over the Central US is forecast to build today, as weak westerly flow passes over it. Weak troughing over the Great Basin will gradually shift eastward bolstering mid-level flow over the region. A weak lee low over the High Plains will support west/southwesterly winds over much of the Great Basin and Intermountain West through this afternoon. 15-20 mph gusts will overlap with very warm and dry conditions (RH below 15) from eastern NV into portions of UT, WY and ID. Several hours of elevated fire weather conditions are probable given very dry and receptive fuels. ...Dry Thunder... Weak height falls from the upper trough over the West will continue to overspread robust monsoon moisture supporting isolated thunderstorms this afternoon. Similar to previous days, a combination of steep mid-level lapse rates and modest mid-level moisture will overlap with dry boundary layer conditions and high cloud bases. This will favor dry storms with limited potential for wetting rainfall. The favorable thermodynamic conditions, coupled with 15-25 knot storm motions over top receptive fuels will continue to support dry lightning potential with these storms over the eastern Great Basin and central Rockies. ..Lyons.. 08/15/2025 ...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 0159 AM CDT Fri Aug 15 2025 Valid 151200Z - 161200Z ...Synopsis... Broad mid-level ridging over the Central US is forecast to build today, as weak westerly flow passes over it. Weak troughing over the Great Basin will gradually shift eastward bolstering mid-level flow over the region. A weak lee low over the High Plains will support west/southwesterly winds over much of the Great Basin and Intermountain West through this afternoon. 15-20 mph gusts will overlap with very warm and dry conditions (RH below 15) from eastern NV into portions of UT, WY and ID. Several hours of elevated fire weather conditions are probable given very dry and receptive fuels. ...Dry Thunder... Weak height falls from the upper trough over the West will continue to overspread robust monsoon moisture supporting isolated thunderstorms this afternoon. Similar to previous days, a combination of steep mid-level lapse rates and modest mid-level moisture will overlap with dry boundary layer conditions and high cloud bases. This will favor dry storms with limited potential for wetting rainfall. The favorable thermodynamic conditions, coupled with 15-25 knot storm motions over top receptive fuels will continue to support dry lightning potential with these storms over the eastern Great Basin and central Rockies. ..Lyons.. 08/15/2025 ...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 0159 AM CDT Fri Aug 15 2025 Valid 151200Z - 161200Z ...Synopsis... Broad mid-level ridging over the Central US is forecast to build today, as weak westerly flow passes over it. Weak troughing over the Great Basin will gradually shift eastward bolstering mid-level flow over the region. A weak lee low over the High Plains will support west/southwesterly winds over much of the Great Basin and Intermountain West through this afternoon. 15-20 mph gusts will overlap with very warm and dry conditions (RH below 15) from eastern NV into portions of UT, WY and ID. Several hours of elevated fire weather conditions are probable given very dry and receptive fuels. ...Dry Thunder... Weak height falls from the upper trough over the West will continue to overspread robust monsoon moisture supporting isolated thunderstorms this afternoon. Similar to previous days, a combination of steep mid-level lapse rates and modest mid-level moisture will overlap with dry boundary layer conditions and high cloud bases. This will favor dry storms with limited potential for wetting rainfall. The favorable thermodynamic conditions, coupled with 15-25 knot storm motions over top receptive fuels will continue to support dry lightning potential with these storms over the eastern Great Basin and central Rockies. ..Lyons.. 08/15/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1256 AM CDT Fri Aug 15 2025 Valid 161200Z - 171200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PARTS OF THE NORTHERN HIGH PLAINS EASTWARD TO THE GREAT LAKES... ...SUMMARY... Thunderstorms with a potential for isolated severe gusts and hail will be possible on Saturday from parts of the central and northern Plains eastward to the Great Lakes. ...Central and Northern Plains... At mid-levels, a ridge will move across the northern Plains on Saturday, as southwesterly flow remains from the northern Rockies into the northern High Plains. At the surface, an upslope flow regime will remain in place from the Dakotas into eastern Montana. A surface trough will deepen during the day over the northern High Plains. Although large-scale ascent will remain weak across the region, isolated thunderstorms may develop in the afternoon near the surface trough. Additional isolated storms could develop near and to the north of a front located across northern Nebraska. To the north of the front, a moist and unstable airmass is forecast. Moderate instability will be in place over much of this airmass by afternoon. Although deep-layer shear will remain near or below 35 knots over most of this airmass, low to mid-level lapse rates will be steep. This could be enough for isolated severe gusts and hail with any cell that can develop and persist in the late afternoon and early evening. ...Upper Mississippi Valley/Great Lakes... West-northwesterly mid-level flow will remain in place on Saturday from the upper Mississippi Valley into the Great Lakes, as a mid-level ridge moves across the northern Plains. At the surface, a front is forecast to remain in place from far northern Iowa into southern Wisconsin. From near the boundary southward, surface dewpoints are forecast to be in the lower to mid 70s F. This will contribute to a strongly unstable airmass by afternoon. Although large-scale ascent will remain weak across the region, isolated thunderstorms may develop along pre-existing boundaries or along zones of maximized low-level convergence. NAM forecast soundings near and to the north of the front across the upper Mississippi Valley have 0-6 km shear in the 30 to 40 knot range, with 700-500 mb lapse rates of 7 to 7.5 C/km. This could be enough for isolated rotating storms with potential for hail and severe wind gusts. A potential for severe gusts could extend eastward into parts of the Great Lakes where moderate instability is forecast, but deep-layer shear will be more modest. ..Broyles.. 08/15/2025 Read more