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SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0229 AM CDT Tue Jun 11 2024 Valid 131200Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS AND MID MISSISSIPPI VALLEY... ...SUMMARY... Thunderstorms associated with large hail and severe gusts will be possible on Thursday in parts of the central Plains and mid Mississippi Valley. Marginally severe storms will also be possible in parts of the Great Lakes and central High Plains. ...Central Plains/Mid Mississippi Valley/Great Lakes... An upper-level trough will move eastward into the Great Lakes region on Thursday, as a cold front advances southward into the central Plains, mid Mississippi Valley and southern Great Lakes. Along and to the south of the front, surface dewpoints in the upper 60s and lower 70s F, will likely contribute to the development of moderate instability by afternoon. As surface temperatures warm during the day, thunderstorms are expected to form along the front, with several clusters of strong to potentially severe storms moving southeastward across the central Plains, mid Mississippi Valley and southern Great Lakes region. The greatest potential for severe storms appears to be from northeast Kansas east-northeastward into north-central Illinois where the models suggest that the strongest instability will develop. Along the front, the NAM has the strongest instability in northeast Kansas, where MLCAPE is forecast to peak in the 4000 to 5000 J/kg range in the late afternoon. At that time, the NAM forecast sounding at Kansas City has gradually veering winds with height, 0-6 km shear near 30 knots, and 700-500 mb lapse rates around 7.5 C/km. This environment would support a potential for supercells with large hail. However, with northwest mid-level flow aloft, persistent convective clusters may tend to organize into line segments with wind-damage potential. The chance for severe wind gusts could extend east-northeastward along a narrow corridor of instability into north-central Illinois, northern Indiana and Lower Michigan. Due to more widely-spaced storms in the Great Lakes region, the threat may be more isolated with northeastward extent. ...Central High Plains... An upper-level ridge is forecast to move eastward through the Rockies on Thursday. A narrow axis of maximized instability and moisture is forecast by afternoon to the east of the ridge from northern Kansas into northeast Colorado and far southwest Wyoming. As surface temperatures warm during the day, isolated to scattered thunderstorms may develop near the instability axis. Although flow is forecast to be relatively weak in the low-levels, speed shear in the mid-levels could be enough for an isolated severe threat. Hail and/or marginally severe wind gusts would be the primary threats. ..Broyles.. 06/11/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0229 AM CDT Tue Jun 11 2024 Valid 131200Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS AND MID MISSISSIPPI VALLEY... ...SUMMARY... Thunderstorms associated with large hail and severe gusts will be possible on Thursday in parts of the central Plains and mid Mississippi Valley. Marginally severe storms will also be possible in parts of the Great Lakes and central High Plains. ...Central Plains/Mid Mississippi Valley/Great Lakes... An upper-level trough will move eastward into the Great Lakes region on Thursday, as a cold front advances southward into the central Plains, mid Mississippi Valley and southern Great Lakes. Along and to the south of the front, surface dewpoints in the upper 60s and lower 70s F, will likely contribute to the development of moderate instability by afternoon. As surface temperatures warm during the day, thunderstorms are expected to form along the front, with several clusters of strong to potentially severe storms moving southeastward across the central Plains, mid Mississippi Valley and southern Great Lakes region. The greatest potential for severe storms appears to be from northeast Kansas east-northeastward into north-central Illinois where the models suggest that the strongest instability will develop. Along the front, the NAM has the strongest instability in northeast Kansas, where MLCAPE is forecast to peak in the 4000 to 5000 J/kg range in the late afternoon. At that time, the NAM forecast sounding at Kansas City has gradually veering winds with height, 0-6 km shear near 30 knots, and 700-500 mb lapse rates around 7.5 C/km. This environment would support a potential for supercells with large hail. However, with northwest mid-level flow aloft, persistent convective clusters may tend to organize into line segments with wind-damage potential. The chance for severe wind gusts could extend east-northeastward along a narrow corridor of instability into north-central Illinois, northern Indiana and Lower Michigan. Due to more widely-spaced storms in the Great Lakes region, the threat may be more isolated with northeastward extent. ...Central High Plains... An upper-level ridge is forecast to move eastward through the Rockies on Thursday. A narrow axis of maximized instability and moisture is forecast by afternoon to the east of the ridge from northern Kansas into northeast Colorado and far southwest Wyoming. As surface temperatures warm during the day, isolated to scattered thunderstorms may develop near the instability axis. Although flow is forecast to be relatively weak in the low-levels, speed shear in the mid-levels could be enough for an isolated severe threat. Hail and/or marginally severe wind gusts would be the primary threats. ..Broyles.. 06/11/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0229 AM CDT Tue Jun 11 2024 Valid 131200Z - 141200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS AND MID MISSISSIPPI VALLEY... ...SUMMARY... Thunderstorms associated with large hail and severe gusts will be possible on Thursday in parts of the central Plains and mid Mississippi Valley. Marginally severe storms will also be possible in parts of the Great Lakes and central High Plains. ...Central Plains/Mid Mississippi Valley/Great Lakes... An upper-level trough will move eastward into the Great Lakes region on Thursday, as a cold front advances southward into the central Plains, mid Mississippi Valley and southern Great Lakes. Along and to the south of the front, surface dewpoints in the upper 60s and lower 70s F, will likely contribute to the development of moderate instability by afternoon. As surface temperatures warm during the day, thunderstorms are expected to form along the front, with several clusters of strong to potentially severe storms moving southeastward across the central Plains, mid Mississippi Valley and southern Great Lakes region. The greatest potential for severe storms appears to be from northeast Kansas east-northeastward into north-central Illinois where the models suggest that the strongest instability will develop. Along the front, the NAM has the strongest instability in northeast Kansas, where MLCAPE is forecast to peak in the 4000 to 5000 J/kg range in the late afternoon. At that time, the NAM forecast sounding at Kansas City has gradually veering winds with height, 0-6 km shear near 30 knots, and 700-500 mb lapse rates around 7.5 C/km. This environment would support a potential for supercells with large hail. However, with northwest mid-level flow aloft, persistent convective clusters may tend to organize into line segments with wind-damage potential. The chance for severe wind gusts could extend east-northeastward along a narrow corridor of instability into north-central Illinois, northern Indiana and Lower Michigan. Due to more widely-spaced storms in the Great Lakes region, the threat may be more isolated with northeastward extent. ...Central High Plains... An upper-level ridge is forecast to move eastward through the Rockies on Thursday. A narrow axis of maximized instability and moisture is forecast by afternoon to the east of the ridge from northern Kansas into northeast Colorado and far southwest Wyoming. As surface temperatures warm during the day, isolated to scattered thunderstorms may develop near the instability axis. Although flow is forecast to be relatively weak in the low-levels, speed shear in the mid-levels could be enough for an isolated severe threat. Hail and/or marginally severe wind gusts would be the primary threats. ..Broyles.. 06/11/2024 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0156 AM CDT Tue Jun 11 2024 Valid 121200Z - 131200Z ...NO CRITICAL AREAS... ...Synopsis... Ahead of a slow-moving midlevel low off the southern CA coast, a belt of moderate southerly flow aloft will overspread the Desert Southwest and southern Great Basin. This will promote modestly breezy southerly surface winds across portions of northern AZ, southern NV, and southern UT -- where a deep/dry boundary layer will be in place. While locally elevated fire-weather conditions are possible here, sustained surface winds appear too marginal for fire-weather highlights, given near-normal fuels across much of the area. ..Weinman.. 06/11/2024 ...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 0156 AM CDT Tue Jun 11 2024 Valid 121200Z - 131200Z ...NO CRITICAL AREAS... ...Synopsis... Ahead of a slow-moving midlevel low off the southern CA coast, a belt of moderate southerly flow aloft will overspread the Desert Southwest and southern Great Basin. This will promote modestly breezy southerly surface winds across portions of northern AZ, southern NV, and southern UT -- where a deep/dry boundary layer will be in place. While locally elevated fire-weather conditions are possible here, sustained surface winds appear too marginal for fire-weather highlights, given near-normal fuels across much of the area. ..Weinman.. 06/11/2024 ...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 0156 AM CDT Tue Jun 11 2024 Valid 121200Z - 131200Z ...NO CRITICAL AREAS... ...Synopsis... Ahead of a slow-moving midlevel low off the southern CA coast, a belt of moderate southerly flow aloft will overspread the Desert Southwest and southern Great Basin. This will promote modestly breezy southerly surface winds across portions of northern AZ, southern NV, and southern UT -- where a deep/dry boundary layer will be in place. While locally elevated fire-weather conditions are possible here, sustained surface winds appear too marginal for fire-weather highlights, given near-normal fuels across much of the area. ..Weinman.. 06/11/2024 ...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 0156 AM CDT Tue Jun 11 2024 Valid 121200Z - 131200Z ...NO CRITICAL AREAS... ...Synopsis... Ahead of a slow-moving midlevel low off the southern CA coast, a belt of moderate southerly flow aloft will overspread the Desert Southwest and southern Great Basin. This will promote modestly breezy southerly surface winds across portions of northern AZ, southern NV, and southern UT -- where a deep/dry boundary layer will be in place. While locally elevated fire-weather conditions are possible here, sustained surface winds appear too marginal for fire-weather highlights, given near-normal fuels across much of the area. ..Weinman.. 06/11/2024 ...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 0156 AM CDT Tue Jun 11 2024 Valid 121200Z - 131200Z ...NO CRITICAL AREAS... ...Synopsis... Ahead of a slow-moving midlevel low off the southern CA coast, a belt of moderate southerly flow aloft will overspread the Desert Southwest and southern Great Basin. This will promote modestly breezy southerly surface winds across portions of northern AZ, southern NV, and southern UT -- where a deep/dry boundary layer will be in place. While locally elevated fire-weather conditions are possible here, sustained surface winds appear too marginal for fire-weather highlights, given near-normal fuels across much of the area. ..Weinman.. 06/11/2024 ...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 0156 AM CDT Tue Jun 11 2024 Valid 111200Z - 121200Z ...NO CRITICAL AREAS... ...Synopsis... A belt of strong westerly midlevel flow will overspread the Pacific Northwest, while a related cold front moves eastward across the region. This will favor downslope warming/drying and a tightening surface pressure gradient east of the Cascades. As a result, locally dry/breezy conditions are expected across portions of eastern WA and OR, and locally elevated fire-weather conditions are possible. However, marginal fuels limit confidence in an appreciable fire-weather threat -- precluding Elevated highlights at this time. Over the Southwest, warm/dry conditions will continue beneath a midlevel ridge. While locally elevated fire-weather conditions are possible (given dry fuels across the region), a modest surface pressure gradient and fairly weak surface winds should limit the overall fire-weather threat. ..Weinman.. 06/11/2024 ...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 0156 AM CDT Tue Jun 11 2024 Valid 111200Z - 121200Z ...NO CRITICAL AREAS... ...Synopsis... A belt of strong westerly midlevel flow will overspread the Pacific Northwest, while a related cold front moves eastward across the region. This will favor downslope warming/drying and a tightening surface pressure gradient east of the Cascades. As a result, locally dry/breezy conditions are expected across portions of eastern WA and OR, and locally elevated fire-weather conditions are possible. However, marginal fuels limit confidence in an appreciable fire-weather threat -- precluding Elevated highlights at this time. Over the Southwest, warm/dry conditions will continue beneath a midlevel ridge. While locally elevated fire-weather conditions are possible (given dry fuels across the region), a modest surface pressure gradient and fairly weak surface winds should limit the overall fire-weather threat. ..Weinman.. 06/11/2024 ...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 0156 AM CDT Tue Jun 11 2024 Valid 111200Z - 121200Z ...NO CRITICAL AREAS... ...Synopsis... A belt of strong westerly midlevel flow will overspread the Pacific Northwest, while a related cold front moves eastward across the region. This will favor downslope warming/drying and a tightening surface pressure gradient east of the Cascades. As a result, locally dry/breezy conditions are expected across portions of eastern WA and OR, and locally elevated fire-weather conditions are possible. However, marginal fuels limit confidence in an appreciable fire-weather threat -- precluding Elevated highlights at this time. Over the Southwest, warm/dry conditions will continue beneath a midlevel ridge. While locally elevated fire-weather conditions are possible (given dry fuels across the region), a modest surface pressure gradient and fairly weak surface winds should limit the overall fire-weather threat. ..Weinman.. 06/11/2024 ...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 0156 AM CDT Tue Jun 11 2024 Valid 111200Z - 121200Z ...NO CRITICAL AREAS... ...Synopsis... A belt of strong westerly midlevel flow will overspread the Pacific Northwest, while a related cold front moves eastward across the region. This will favor downslope warming/drying and a tightening surface pressure gradient east of the Cascades. As a result, locally dry/breezy conditions are expected across portions of eastern WA and OR, and locally elevated fire-weather conditions are possible. However, marginal fuels limit confidence in an appreciable fire-weather threat -- precluding Elevated highlights at this time. Over the Southwest, warm/dry conditions will continue beneath a midlevel ridge. While locally elevated fire-weather conditions are possible (given dry fuels across the region), a modest surface pressure gradient and fairly weak surface winds should limit the overall fire-weather threat. ..Weinman.. 06/11/2024 ...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 0156 AM CDT Tue Jun 11 2024 Valid 111200Z - 121200Z ...NO CRITICAL AREAS... ...Synopsis... A belt of strong westerly midlevel flow will overspread the Pacific Northwest, while a related cold front moves eastward across the region. This will favor downslope warming/drying and a tightening surface pressure gradient east of the Cascades. As a result, locally dry/breezy conditions are expected across portions of eastern WA and OR, and locally elevated fire-weather conditions are possible. However, marginal fuels limit confidence in an appreciable fire-weather threat -- precluding Elevated highlights at this time. Over the Southwest, warm/dry conditions will continue beneath a midlevel ridge. While locally elevated fire-weather conditions are possible (given dry fuels across the region), a modest surface pressure gradient and fairly weak surface winds should limit the overall fire-weather threat. ..Weinman.. 06/11/2024 ...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 1258 AM CDT Tue Jun 11 2024 Valid 121200Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE UPPER MIDWEST... ...SUMMARY... Thunderstorms associated with large hail and severe wind gusts, and perhaps a tornado or two are expected on Wednesday in parts of the Upper Midwest. ...Upper Midwest... A belt of strong mid-level flow will be in place on Wednesday across the far northern U.S. Within the flow, a 60 to 80 knot mid-level jet is forecast to move eastward across far southern Saskatchewan. The exit region of this feature will overspread the upper Mississippi Valley during the day, strengthening large-scale ascent and deep-layer shear. At the surface, a cold front will advance eastward through the eastern Dakotas. Ahead of the front, surface dewpoints will likely reach the lower to mid 60s F from the mid Missouri Valley northeastward into the upper Mississippi Valley. During the afternoon, surface-based thunderstorms are expected to form along the western edge of the moist airmass, from eastern South Dakota into western Minnesota. These storms are expected to gradually increase in coverage, moving eastward into the upper Mississippi Valley during the late afternoon and early evening. NAM forecast soundings near the instability axis at 00Z/Thursday from central Minnesota into far northwest Iowa have MLCAPE in the 1500 to 2500 J/kg range, 0-6 km shear around 45 knots, and 700-500 mb lapse rates near 7.5 C/km. This environment will favorable for severe storms. The stronger cells could become supercellular and have a large hail threat. Hailstones greater than 2 inches in diameter will be possible with supercells that form in areas that destabilize the most. Some model solutions suggest that cells could be separated enough to favor discrete modes. By early evening, forecast soundings increase 0-3 km storm-relative into the 200 to 250 m2/s2 range. These factors would support an isolated tornado threat with the more intense supercells. A wind-damage threat will also be possible with supercells, and with organized short line segments. The severe threat should continue into the mid to late evening as storms move eastward into the far western Great Lakes region. ..Broyles.. 06/11/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Tue Jun 11 2024 Valid 121200Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE UPPER MIDWEST... ...SUMMARY... Thunderstorms associated with large hail and severe wind gusts, and perhaps a tornado or two are expected on Wednesday in parts of the Upper Midwest. ...Upper Midwest... A belt of strong mid-level flow will be in place on Wednesday across the far northern U.S. Within the flow, a 60 to 80 knot mid-level jet is forecast to move eastward across far southern Saskatchewan. The exit region of this feature will overspread the upper Mississippi Valley during the day, strengthening large-scale ascent and deep-layer shear. At the surface, a cold front will advance eastward through the eastern Dakotas. Ahead of the front, surface dewpoints will likely reach the lower to mid 60s F from the mid Missouri Valley northeastward into the upper Mississippi Valley. During the afternoon, surface-based thunderstorms are expected to form along the western edge of the moist airmass, from eastern South Dakota into western Minnesota. These storms are expected to gradually increase in coverage, moving eastward into the upper Mississippi Valley during the late afternoon and early evening. NAM forecast soundings near the instability axis at 00Z/Thursday from central Minnesota into far northwest Iowa have MLCAPE in the 1500 to 2500 J/kg range, 0-6 km shear around 45 knots, and 700-500 mb lapse rates near 7.5 C/km. This environment will favorable for severe storms. The stronger cells could become supercellular and have a large hail threat. Hailstones greater than 2 inches in diameter will be possible with supercells that form in areas that destabilize the most. Some model solutions suggest that cells could be separated enough to favor discrete modes. By early evening, forecast soundings increase 0-3 km storm-relative into the 200 to 250 m2/s2 range. These factors would support an isolated tornado threat with the more intense supercells. A wind-damage threat will also be possible with supercells, and with organized short line segments. The severe threat should continue into the mid to late evening as storms move eastward into the far western Great Lakes region. ..Broyles.. 06/11/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Tue Jun 11 2024 Valid 121200Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE UPPER MIDWEST... ...SUMMARY... Thunderstorms associated with large hail and severe wind gusts, and perhaps a tornado or two are expected on Wednesday in parts of the Upper Midwest. ...Upper Midwest... A belt of strong mid-level flow will be in place on Wednesday across the far northern U.S. Within the flow, a 60 to 80 knot mid-level jet is forecast to move eastward across far southern Saskatchewan. The exit region of this feature will overspread the upper Mississippi Valley during the day, strengthening large-scale ascent and deep-layer shear. At the surface, a cold front will advance eastward through the eastern Dakotas. Ahead of the front, surface dewpoints will likely reach the lower to mid 60s F from the mid Missouri Valley northeastward into the upper Mississippi Valley. During the afternoon, surface-based thunderstorms are expected to form along the western edge of the moist airmass, from eastern South Dakota into western Minnesota. These storms are expected to gradually increase in coverage, moving eastward into the upper Mississippi Valley during the late afternoon and early evening. NAM forecast soundings near the instability axis at 00Z/Thursday from central Minnesota into far northwest Iowa have MLCAPE in the 1500 to 2500 J/kg range, 0-6 km shear around 45 knots, and 700-500 mb lapse rates near 7.5 C/km. This environment will favorable for severe storms. The stronger cells could become supercellular and have a large hail threat. Hailstones greater than 2 inches in diameter will be possible with supercells that form in areas that destabilize the most. Some model solutions suggest that cells could be separated enough to favor discrete modes. By early evening, forecast soundings increase 0-3 km storm-relative into the 200 to 250 m2/s2 range. These factors would support an isolated tornado threat with the more intense supercells. A wind-damage threat will also be possible with supercells, and with organized short line segments. The severe threat should continue into the mid to late evening as storms move eastward into the far western Great Lakes region. ..Broyles.. 06/11/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Tue Jun 11 2024 Valid 121200Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE UPPER MIDWEST... ...SUMMARY... Thunderstorms associated with large hail and severe wind gusts, and perhaps a tornado or two are expected on Wednesday in parts of the Upper Midwest. ...Upper Midwest... A belt of strong mid-level flow will be in place on Wednesday across the far northern U.S. Within the flow, a 60 to 80 knot mid-level jet is forecast to move eastward across far southern Saskatchewan. The exit region of this feature will overspread the upper Mississippi Valley during the day, strengthening large-scale ascent and deep-layer shear. At the surface, a cold front will advance eastward through the eastern Dakotas. Ahead of the front, surface dewpoints will likely reach the lower to mid 60s F from the mid Missouri Valley northeastward into the upper Mississippi Valley. During the afternoon, surface-based thunderstorms are expected to form along the western edge of the moist airmass, from eastern South Dakota into western Minnesota. These storms are expected to gradually increase in coverage, moving eastward into the upper Mississippi Valley during the late afternoon and early evening. NAM forecast soundings near the instability axis at 00Z/Thursday from central Minnesota into far northwest Iowa have MLCAPE in the 1500 to 2500 J/kg range, 0-6 km shear around 45 knots, and 700-500 mb lapse rates near 7.5 C/km. This environment will favorable for severe storms. The stronger cells could become supercellular and have a large hail threat. Hailstones greater than 2 inches in diameter will be possible with supercells that form in areas that destabilize the most. Some model solutions suggest that cells could be separated enough to favor discrete modes. By early evening, forecast soundings increase 0-3 km storm-relative into the 200 to 250 m2/s2 range. These factors would support an isolated tornado threat with the more intense supercells. A wind-damage threat will also be possible with supercells, and with organized short line segments. The severe threat should continue into the mid to late evening as storms move eastward into the far western Great Lakes region. ..Broyles.. 06/11/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1258 AM CDT Tue Jun 11 2024 Valid 121200Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE UPPER MIDWEST... ...SUMMARY... Thunderstorms associated with large hail and severe wind gusts, and perhaps a tornado or two are expected on Wednesday in parts of the Upper Midwest. ...Upper Midwest... A belt of strong mid-level flow will be in place on Wednesday across the far northern U.S. Within the flow, a 60 to 80 knot mid-level jet is forecast to move eastward across far southern Saskatchewan. The exit region of this feature will overspread the upper Mississippi Valley during the day, strengthening large-scale ascent and deep-layer shear. At the surface, a cold front will advance eastward through the eastern Dakotas. Ahead of the front, surface dewpoints will likely reach the lower to mid 60s F from the mid Missouri Valley northeastward into the upper Mississippi Valley. During the afternoon, surface-based thunderstorms are expected to form along the western edge of the moist airmass, from eastern South Dakota into western Minnesota. These storms are expected to gradually increase in coverage, moving eastward into the upper Mississippi Valley during the late afternoon and early evening. NAM forecast soundings near the instability axis at 00Z/Thursday from central Minnesota into far northwest Iowa have MLCAPE in the 1500 to 2500 J/kg range, 0-6 km shear around 45 knots, and 700-500 mb lapse rates near 7.5 C/km. This environment will favorable for severe storms. The stronger cells could become supercellular and have a large hail threat. Hailstones greater than 2 inches in diameter will be possible with supercells that form in areas that destabilize the most. Some model solutions suggest that cells could be separated enough to favor discrete modes. By early evening, forecast soundings increase 0-3 km storm-relative into the 200 to 250 m2/s2 range. These factors would support an isolated tornado threat with the more intense supercells. A wind-damage threat will also be possible with supercells, and with organized short line segments. The severe threat should continue into the mid to late evening as storms move eastward into the far western Great Lakes region. ..Broyles.. 06/11/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1230 AM CDT Tue Jun 11 2024 Valid 111200Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF TEXAS CENTERED ON THE EDWARDS PLATEAU REGION... ...SUMMARY... Scattered thunderstorms are possible across portions of Texas centered on the Edwards Plateau. Hail and gusty winds are the primary threats. ...Texas... Weak upper low is currently centered near the NM/TX border northwest of LBB. This feature is forecast to drift southeast during the day1 period which will ensure a belt of modest 500mb northwesterly flow will stretch across much of west into south-central Texas. Low-level flow will remain weak ahead of this feature and any notable surface boundaries are not evident at this time for potential convective concentration. However, some boundary-layer heating is expected just downstream of the digging trough and this should contribute to destabilization such that robust convection is possible as surface temperatures warm through the 80s. While forecast instability is not expected to be particularly strong (MLCAPE around 1000 J/kg), ample surface-6km bulk shear should contribute to some multi cell storm organization and a few supercells. Gusty winds and hail are the primary risks during the afternoon/evening hours. ...Elsewhere... A few strong storms are expected along the Front Range of the Rockies from northeast NM into central CO. A few strong storms may also develop ahead of a short-wave trough over the upper MS Valley region where gusty winds and marginally severe hail could be noted. A few robust storms may also evolve along the coastal middle Atlantic from southeast VA into eastern NC. In each of these regions the severe threat appears too limited to warrant more than a MRGL risk for wind/hail. ..Darrow/Weinman.. 06/11/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1230 AM CDT Tue Jun 11 2024 Valid 111200Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF TEXAS CENTERED ON THE EDWARDS PLATEAU REGION... ...SUMMARY... Scattered thunderstorms are possible across portions of Texas centered on the Edwards Plateau. Hail and gusty winds are the primary threats. ...Texas... Weak upper low is currently centered near the NM/TX border northwest of LBB. This feature is forecast to drift southeast during the day1 period which will ensure a belt of modest 500mb northwesterly flow will stretch across much of west into south-central Texas. Low-level flow will remain weak ahead of this feature and any notable surface boundaries are not evident at this time for potential convective concentration. However, some boundary-layer heating is expected just downstream of the digging trough and this should contribute to destabilization such that robust convection is possible as surface temperatures warm through the 80s. While forecast instability is not expected to be particularly strong (MLCAPE around 1000 J/kg), ample surface-6km bulk shear should contribute to some multi cell storm organization and a few supercells. Gusty winds and hail are the primary risks during the afternoon/evening hours. ...Elsewhere... A few strong storms are expected along the Front Range of the Rockies from northeast NM into central CO. A few strong storms may also develop ahead of a short-wave trough over the upper MS Valley region where gusty winds and marginally severe hail could be noted. A few robust storms may also evolve along the coastal middle Atlantic from southeast VA into eastern NC. In each of these regions the severe threat appears too limited to warrant more than a MRGL risk for wind/hail. ..Darrow/Weinman.. 06/11/2024 Read more