Severe Storms

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

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

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

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

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

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1232 AM CDT Fri Aug 15 2025 Valid 151200Z - 161200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Scattered severe storms are likely over parts of the northern Plains and Upper Mississippi Valley. ...Northern Plains/Upper MS Valley... Broad anticyclonic flow is forecast to continue across the central/southern Plains during the day1 period. Stronger 500mb flow will extend around the periphery of this feature, extending from the northern Rockies-northern Plains-upper Great Lakes. While a few disturbances will eject across the northern Rockies toward the upper MS Valley, latest model guidance suggests heights will actually rise much of the period. One such feature currently extends from eastern WY into northeast CO. Scattered thunderstorms are noted immediately downstream from the Black Hills into western NE. This disturbance should advance into central SD by the start of the period, then into MN by early afternoon. While a few strong storms may be ongoing at the start of the period, renewed development is expected during the afternoon across the upper MS Valley. LLJ is forecast to increase a bit into southwest MN ahead of the short wave, and this should encourage robust convection along a front that will be draped from southwest MN-northern WI. Strong buoyancy will be noted south of the front across much of this region and MLCAPE could exceed 3000 J/kg from MN/IA into SD/NE. While the short wave should encourage organized convection, boundary-layer heating will prove instrumental in thunderstorm development. Forecast soundings suggest CINH weakens considerably by 19-21z and convection should expand in areal coverage as convective temperatures are breached. Wind/hail are the primary risks, though a brief tornado can not be ruled out with any supercell structures. Farther west, convective temperatures will be breached across eastern WY by 22z. Scattered storms will once again develop over the higher terrain/Plains then spread downstream into western SD/northwestern NE during the evening. Some consideration was given to a SLGT risk for this activity but the short-wave trough that should affect this region will eject across northern AZ into southwest WY around 16/00z. Timing of this feature suggests stronger support will not affect this region until well after sunset. ..Darrow/Lyons.. 08/15/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1232 AM CDT Fri Aug 15 2025 Valid 151200Z - 161200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Scattered severe storms are likely over parts of the northern Plains and Upper Mississippi Valley. ...Northern Plains/Upper MS Valley... Broad anticyclonic flow is forecast to continue across the central/southern Plains during the day1 period. Stronger 500mb flow will extend around the periphery of this feature, extending from the northern Rockies-northern Plains-upper Great Lakes. While a few disturbances will eject across the northern Rockies toward the upper MS Valley, latest model guidance suggests heights will actually rise much of the period. One such feature currently extends from eastern WY into northeast CO. Scattered thunderstorms are noted immediately downstream from the Black Hills into western NE. This disturbance should advance into central SD by the start of the period, then into MN by early afternoon. While a few strong storms may be ongoing at the start of the period, renewed development is expected during the afternoon across the upper MS Valley. LLJ is forecast to increase a bit into southwest MN ahead of the short wave, and this should encourage robust convection along a front that will be draped from southwest MN-northern WI. Strong buoyancy will be noted south of the front across much of this region and MLCAPE could exceed 3000 J/kg from MN/IA into SD/NE. While the short wave should encourage organized convection, boundary-layer heating will prove instrumental in thunderstorm development. Forecast soundings suggest CINH weakens considerably by 19-21z and convection should expand in areal coverage as convective temperatures are breached. Wind/hail are the primary risks, though a brief tornado can not be ruled out with any supercell structures. Farther west, convective temperatures will be breached across eastern WY by 22z. Scattered storms will once again develop over the higher terrain/Plains then spread downstream into western SD/northwestern NE during the evening. Some consideration was given to a SLGT risk for this activity but the short-wave trough that should affect this region will eject across northern AZ into southwest WY around 16/00z. Timing of this feature suggests stronger support will not affect this region until well after sunset. ..Darrow/Lyons.. 08/15/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1232 AM CDT Fri Aug 15 2025 Valid 151200Z - 161200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Scattered severe storms are likely over parts of the northern Plains and Upper Mississippi Valley. ...Northern Plains/Upper MS Valley... Broad anticyclonic flow is forecast to continue across the central/southern Plains during the day1 period. Stronger 500mb flow will extend around the periphery of this feature, extending from the northern Rockies-northern Plains-upper Great Lakes. While a few disturbances will eject across the northern Rockies toward the upper MS Valley, latest model guidance suggests heights will actually rise much of the period. One such feature currently extends from eastern WY into northeast CO. Scattered thunderstorms are noted immediately downstream from the Black Hills into western NE. This disturbance should advance into central SD by the start of the period, then into MN by early afternoon. While a few strong storms may be ongoing at the start of the period, renewed development is expected during the afternoon across the upper MS Valley. LLJ is forecast to increase a bit into southwest MN ahead of the short wave, and this should encourage robust convection along a front that will be draped from southwest MN-northern WI. Strong buoyancy will be noted south of the front across much of this region and MLCAPE could exceed 3000 J/kg from MN/IA into SD/NE. While the short wave should encourage organized convection, boundary-layer heating will prove instrumental in thunderstorm development. Forecast soundings suggest CINH weakens considerably by 19-21z and convection should expand in areal coverage as convective temperatures are breached. Wind/hail are the primary risks, though a brief tornado can not be ruled out with any supercell structures. Farther west, convective temperatures will be breached across eastern WY by 22z. Scattered storms will once again develop over the higher terrain/Plains then spread downstream into western SD/northwestern NE during the evening. Some consideration was given to a SLGT risk for this activity but the short-wave trough that should affect this region will eject across northern AZ into southwest WY around 16/00z. Timing of this feature suggests stronger support will not affect this region until well after sunset. ..Darrow/Lyons.. 08/15/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1232 AM CDT Fri Aug 15 2025 Valid 151200Z - 161200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Scattered severe storms are likely over parts of the northern Plains and Upper Mississippi Valley. ...Northern Plains/Upper MS Valley... Broad anticyclonic flow is forecast to continue across the central/southern Plains during the day1 period. Stronger 500mb flow will extend around the periphery of this feature, extending from the northern Rockies-northern Plains-upper Great Lakes. While a few disturbances will eject across the northern Rockies toward the upper MS Valley, latest model guidance suggests heights will actually rise much of the period. One such feature currently extends from eastern WY into northeast CO. Scattered thunderstorms are noted immediately downstream from the Black Hills into western NE. This disturbance should advance into central SD by the start of the period, then into MN by early afternoon. While a few strong storms may be ongoing at the start of the period, renewed development is expected during the afternoon across the upper MS Valley. LLJ is forecast to increase a bit into southwest MN ahead of the short wave, and this should encourage robust convection along a front that will be draped from southwest MN-northern WI. Strong buoyancy will be noted south of the front across much of this region and MLCAPE could exceed 3000 J/kg from MN/IA into SD/NE. While the short wave should encourage organized convection, boundary-layer heating will prove instrumental in thunderstorm development. Forecast soundings suggest CINH weakens considerably by 19-21z and convection should expand in areal coverage as convective temperatures are breached. Wind/hail are the primary risks, though a brief tornado can not be ruled out with any supercell structures. Farther west, convective temperatures will be breached across eastern WY by 22z. Scattered storms will once again develop over the higher terrain/Plains then spread downstream into western SD/northwestern NE during the evening. Some consideration was given to a SLGT risk for this activity but the short-wave trough that should affect this region will eject across northern AZ into southwest WY around 16/00z. Timing of this feature suggests stronger support will not affect this region until well after sunset. ..Darrow/Lyons.. 08/15/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1232 AM CDT Fri Aug 15 2025 Valid 151200Z - 161200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Scattered severe storms are likely over parts of the northern Plains and Upper Mississippi Valley. ...Northern Plains/Upper MS Valley... Broad anticyclonic flow is forecast to continue across the central/southern Plains during the day1 period. Stronger 500mb flow will extend around the periphery of this feature, extending from the northern Rockies-northern Plains-upper Great Lakes. While a few disturbances will eject across the northern Rockies toward the upper MS Valley, latest model guidance suggests heights will actually rise much of the period. One such feature currently extends from eastern WY into northeast CO. Scattered thunderstorms are noted immediately downstream from the Black Hills into western NE. This disturbance should advance into central SD by the start of the period, then into MN by early afternoon. While a few strong storms may be ongoing at the start of the period, renewed development is expected during the afternoon across the upper MS Valley. LLJ is forecast to increase a bit into southwest MN ahead of the short wave, and this should encourage robust convection along a front that will be draped from southwest MN-northern WI. Strong buoyancy will be noted south of the front across much of this region and MLCAPE could exceed 3000 J/kg from MN/IA into SD/NE. While the short wave should encourage organized convection, boundary-layer heating will prove instrumental in thunderstorm development. Forecast soundings suggest CINH weakens considerably by 19-21z and convection should expand in areal coverage as convective temperatures are breached. Wind/hail are the primary risks, though a brief tornado can not be ruled out with any supercell structures. Farther west, convective temperatures will be breached across eastern WY by 22z. Scattered storms will once again develop over the higher terrain/Plains then spread downstream into western SD/northwestern NE during the evening. Some consideration was given to a SLGT risk for this activity but the short-wave trough that should affect this region will eject across northern AZ into southwest WY around 16/00z. Timing of this feature suggests stronger support will not affect this region until well after sunset. ..Darrow/Lyons.. 08/15/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1232 AM CDT Fri Aug 15 2025 Valid 151200Z - 161200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Scattered severe storms are likely over parts of the northern Plains and Upper Mississippi Valley. ...Northern Plains/Upper MS Valley... Broad anticyclonic flow is forecast to continue across the central/southern Plains during the day1 period. Stronger 500mb flow will extend around the periphery of this feature, extending from the northern Rockies-northern Plains-upper Great Lakes. While a few disturbances will eject across the northern Rockies toward the upper MS Valley, latest model guidance suggests heights will actually rise much of the period. One such feature currently extends from eastern WY into northeast CO. Scattered thunderstorms are noted immediately downstream from the Black Hills into western NE. This disturbance should advance into central SD by the start of the period, then into MN by early afternoon. While a few strong storms may be ongoing at the start of the period, renewed development is expected during the afternoon across the upper MS Valley. LLJ is forecast to increase a bit into southwest MN ahead of the short wave, and this should encourage robust convection along a front that will be draped from southwest MN-northern WI. Strong buoyancy will be noted south of the front across much of this region and MLCAPE could exceed 3000 J/kg from MN/IA into SD/NE. While the short wave should encourage organized convection, boundary-layer heating will prove instrumental in thunderstorm development. Forecast soundings suggest CINH weakens considerably by 19-21z and convection should expand in areal coverage as convective temperatures are breached. Wind/hail are the primary risks, though a brief tornado can not be ruled out with any supercell structures. Farther west, convective temperatures will be breached across eastern WY by 22z. Scattered storms will once again develop over the higher terrain/Plains then spread downstream into western SD/northwestern NE during the evening. Some consideration was given to a SLGT risk for this activity but the short-wave trough that should affect this region will eject across northern AZ into southwest WY around 16/00z. Timing of this feature suggests stronger support will not affect this region until well after sunset. ..Darrow/Lyons.. 08/15/2025 Read more

MD 1948 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR PARTS OF NORTHEASTERN NORTH DAKOA AND NORTHWESTERN MINNESOTA
Mesoscale Discussion 1948 NWS Storm Prediction Center Norman OK 0849 PM CDT Thu Aug 14 2025 Areas affected...parts of northeastern North Dakoa and northwestern Minnesota Concerning...Severe potential...Watch possible Valid 150149Z - 150345Z Probability of Watch Issuance...40 percent SUMMARY...Isolated strong thunderstorm development is underway, with additional intensification and a few additional developing cells possible through 10-11 PM CDT. Although this activity may pose a risk for severe hail and localized strong surface gusts, it is not clear that a severe weather watch is needed. However, trends are being monitored. DISCUSSION...Stronger forcing for ascent associated with a vigorous short wave trough progressing to the east the Canadian Prairies remains generally well to the north of the international border. However, the latest Rapid Refresh indicates a focused area of difluent and divergent upper flow just ahead of the southern periphery of this feature overspreading the international border vicinity. This, coupled with lift along an eastward advancing cold front, appears to have contributed to sufficient weakening of mid-level inhibition to support a recently developing storm passing to the north/northeast of the Grand Forks ND vicinity. This is occurring on the southern fringe of the stronger westerlies, where deep-layer shear for boundary-layer based thunderstorm development is conducive to supercells, and there does appear a window of opportunity for this convective to acquire inflow of seasonably moist air characterized by large CAPE. For how long remains unclear, as convection may tend to become undercut by the weak cold front and the pre-frontal boundary-layer undergoes diurnal cooling beneath relatively warm mid-levels. Still, at least some further intensification of ongoing convection, with perhaps a couple of additional intensifying cells appears possible into mid/late evening, accompanied by a risk for severe hail and locally strong surface gusts. ..Kerr/Guyer.. 08/15/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...FGF... LAT...LON 48929488 48339494 46929616 46929783 48129743 48829698 49089649 48929488 MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...1.50-2.50 IN Read more

MD 1947 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PARTS OF SOUTHWESTERN MINNESOTA
Mesoscale Discussion 1947 NWS Storm Prediction Center Norman OK 0652 PM CDT Thu Aug 14 2025 Areas affected...parts of southwestern Minnesota Concerning...Severe potential...Watch unlikely Valid 142352Z - 150145Z Probability of Watch Issuance...5 percent SUMMARY...An isolated supercell may persist into the 8-9 PM CDT time frame, before dissipating. DISCUSSION...Although initially moderate south-southwesterly flow around 850 mb has weakened/shifted east during the past few hours, and temperatures further aloft (roughly centered around 700 mb) have begun to slowly warm, a focused area of low-level convergence and lower/mid-tropospheric warm advection have contributed to sufficient lift to maintain isolated supercell development to the west-northwest through west of Redwood Falls. This activity has been slowly propagating south-southeastward along a warm frontal zone, beneath moderately sheared west-northwesterly deep layer mean flow on the order of 25 kts, likely aided by updraft inflow of boundary-layer air characterized by seasonably high moisture content and sizable CAPE. While there has been some recent weakening evident, it may not be out of the question that activity could undergo re-intensification during the next hour or so. Thereafter, though, increasing inhibition due to the onset of boundary-layer cooling and a bit more substantive warming aloft are expected suppress convective development further and lead to a rapid dissipation. ..Kerr/Guyer.. 08/14/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MPX...FSD... LAT...LON 44479543 44309499 44069520 44079605 44549614 44479543 MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN Read more

MD 1946 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF EASTERN COLORADO...WYOMING INTO WESTERN NEBRASKA AND NORTHWEST KANSAS
Mesoscale Discussion 1946 NWS Storm Prediction Center Norman OK 0630 PM CDT Thu Aug 14 2025 Areas affected...portions of eastern Colorado...Wyoming into western Nebraska and northwest Kansas Concerning...Severe potential...Watch unlikely Valid 142330Z - 150130Z Probability of Watch Issuance...20 percent SUMMARY...High-based storms should continue to increase in coverage this evening. Isolated severe gusts and small hail are possible. DISCUSSION...As of 2325 UTC, regional radar and satellite imagery showed scattered, high-based thunderstorms ongoing across portions of eastern CO and southeastern WY. Storm coverage has slowly increased this evening following strong diurnal heating and weak upslope flow across portions of the central High Plains. Surface observations and regional model soundings show these storms are developing atop a deeply mixed boundary layer with T/TD spreads near 40 degrees F. A few stronger gusts have already been noted with the initial convection. While buoyancy is somewhat low (500-1000 J/kg), the dry low-levels and high cloud bases will continue to support isolated strong to severe gusts from outflow with this activity as it moves across central High Plains over the next couple of hours. With time, these storms should cluster and may gradually encounter deeper moisture and larger buoyancy farther east, which could support some risk for damaging gusts and small hail into tonight. However residual capping, the loss of diurnal heating and lack of stronger forcing for ascent casts uncertainty on the longevity of any stronger clusters that emerge. Given this, and the general lack of broader storm organization owing to modest deep-layer shear, confidence in a sustained severe risk is low. Conditions will continue to be monitored, but currently a WW is unlikely. ..Lyons/Guyer.. 08/14/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LBF...UNR...GLD...BOU...CYS... LAT...LON 40420454 41160468 42890429 43320278 42830075 41610051 40440088 39270188 38870234 38880353 40420454 MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0735 PM CDT Thu Aug 14 2025 Valid 150100Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Thunderstorms capable of producing large hail and severe wind gusts may occur tonight across parts of the northern Plains and upper Mississippi Valley. ...Northern Plains/Upper MS Valley... Low-amplitude short-wave trough is currently noted across southeast SK/northeast MT, shifting east in line with latest model guidance. This feature is forecast to shift across western MB by 15/06z, with the southern influence of weak height falls expected into the upper Red River Region later tonight. Scattered thunderstorms have developed ahead of this feature across southeast MB/northwest ON, but trailing convection along the front south of the border is weak/shallow. Even so, with time isolated-scattered thunderstorms are expected to develop. 00z sounding from ABR exhibited substantial capping near 800mb, but MLCAPE was appreciable with ~3500 J/kg. Additionally, 0-6km shear was also strong, and more than adequate for supercells. Frontal ascent will likely aid convection later this evening, and earlier thoughts regarding the evolution of severe remain. ..Darrow.. 08/15/2025 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0735 PM CDT Thu Aug 14 2025 Valid 150100Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Thunderstorms capable of producing large hail and severe wind gusts may occur tonight across parts of the northern Plains and upper Mississippi Valley. ...Northern Plains/Upper MS Valley... Low-amplitude short-wave trough is currently noted across southeast SK/northeast MT, shifting east in line with latest model guidance. This feature is forecast to shift across western MB by 15/06z, with the southern influence of weak height falls expected into the upper Red River Region later tonight. Scattered thunderstorms have developed ahead of this feature across southeast MB/northwest ON, but trailing convection along the front south of the border is weak/shallow. Even so, with time isolated-scattered thunderstorms are expected to develop. 00z sounding from ABR exhibited substantial capping near 800mb, but MLCAPE was appreciable with ~3500 J/kg. Additionally, 0-6km shear was also strong, and more than adequate for supercells. Frontal ascent will likely aid convection later this evening, and earlier thoughts regarding the evolution of severe remain. ..Darrow.. 08/15/2025 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0735 PM CDT Thu Aug 14 2025 Valid 150100Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Thunderstorms capable of producing large hail and severe wind gusts may occur tonight across parts of the northern Plains and upper Mississippi Valley. ...Northern Plains/Upper MS Valley... Low-amplitude short-wave trough is currently noted across southeast SK/northeast MT, shifting east in line with latest model guidance. This feature is forecast to shift across western MB by 15/06z, with the southern influence of weak height falls expected into the upper Red River Region later tonight. Scattered thunderstorms have developed ahead of this feature across southeast MB/northwest ON, but trailing convection along the front south of the border is weak/shallow. Even so, with time isolated-scattered thunderstorms are expected to develop. 00z sounding from ABR exhibited substantial capping near 800mb, but MLCAPE was appreciable with ~3500 J/kg. Additionally, 0-6km shear was also strong, and more than adequate for supercells. Frontal ascent will likely aid convection later this evening, and earlier thoughts regarding the evolution of severe remain. ..Darrow.. 08/15/2025 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0735 PM CDT Thu Aug 14 2025 Valid 150100Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Thunderstorms capable of producing large hail and severe wind gusts may occur tonight across parts of the northern Plains and upper Mississippi Valley. ...Northern Plains/Upper MS Valley... Low-amplitude short-wave trough is currently noted across southeast SK/northeast MT, shifting east in line with latest model guidance. This feature is forecast to shift across western MB by 15/06z, with the southern influence of weak height falls expected into the upper Red River Region later tonight. Scattered thunderstorms have developed ahead of this feature across southeast MB/northwest ON, but trailing convection along the front south of the border is weak/shallow. Even so, with time isolated-scattered thunderstorms are expected to develop. 00z sounding from ABR exhibited substantial capping near 800mb, but MLCAPE was appreciable with ~3500 J/kg. Additionally, 0-6km shear was also strong, and more than adequate for supercells. Frontal ascent will likely aid convection later this evening, and earlier thoughts regarding the evolution of severe remain. ..Darrow.. 08/15/2025 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0735 PM CDT Thu Aug 14 2025 Valid 150100Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Thunderstorms capable of producing large hail and severe wind gusts may occur tonight across parts of the northern Plains and upper Mississippi Valley. ...Northern Plains/Upper MS Valley... Low-amplitude short-wave trough is currently noted across southeast SK/northeast MT, shifting east in line with latest model guidance. This feature is forecast to shift across western MB by 15/06z, with the southern influence of weak height falls expected into the upper Red River Region later tonight. Scattered thunderstorms have developed ahead of this feature across southeast MB/northwest ON, but trailing convection along the front south of the border is weak/shallow. Even so, with time isolated-scattered thunderstorms are expected to develop. 00z sounding from ABR exhibited substantial capping near 800mb, but MLCAPE was appreciable with ~3500 J/kg. Additionally, 0-6km shear was also strong, and more than adequate for supercells. Frontal ascent will likely aid convection later this evening, and earlier thoughts regarding the evolution of severe remain. ..Darrow.. 08/15/2025 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0735 PM CDT Thu Aug 14 2025 Valid 150100Z - 151200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS AND UPPER MISSISSIPPI VALLEY... ...SUMMARY... Thunderstorms capable of producing large hail and severe wind gusts may occur tonight across parts of the northern Plains and upper Mississippi Valley. ...Northern Plains/Upper MS Valley... Low-amplitude short-wave trough is currently noted across southeast SK/northeast MT, shifting east in line with latest model guidance. This feature is forecast to shift across western MB by 15/06z, with the southern influence of weak height falls expected into the upper Red River Region later tonight. Scattered thunderstorms have developed ahead of this feature across southeast MB/northwest ON, but trailing convection along the front south of the border is weak/shallow. Even so, with time isolated-scattered thunderstorms are expected to develop. 00z sounding from ABR exhibited substantial capping near 800mb, but MLCAPE was appreciable with ~3500 J/kg. Additionally, 0-6km shear was also strong, and more than adequate for supercells. Frontal ascent will likely aid convection later this evening, and earlier thoughts regarding the evolution of severe remain. ..Darrow.. 08/15/2025 Read more