Severe Storms

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Tue Apr 15 2025 Valid 152000Z - 161200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHEAST AND NEW ENGLAND... ...SUMMARY... Isolated wind damage will remain possible into the early evening across parts of the Northeast. ...20Z Northeast... The prior outlooks remains largely unchanged with only minor modifications. Broad-scale ascent beneath the upper low over the Eastern US is supporting scattered, but shallow convection across the Northeast and New England. Low-topped thunderstorms will likely continue to pose a risk for occasional damaging gusts this afternoon. Limited moisture, and resulting buoyancy will continue to be the limiting factor for more sustained/stronger storms. Have trimmed the western extent of the Thunder area over parts of PA/OH. Scattered non-severe storms are also possible over the Four Corners and western US, see the previous discussion for more info. ..Lyons.. 04/15/2025 .PREV DISCUSSION... /ISSUED 1114 AM CDT Tue Apr 15 2025/ ...Northeast... Within the base of an eastward-moving large-scale trough over the eastern CONUS, a related 100+ kt midlevel jet streak will pivot eastward across the Mid-Atlantic and Northeast today. Ascent in the left-exit region of the jet will promote widely scattered, low-topped convection across the Northeast through the afternoon. Despite limited post-frontal boundary-layer moisture, diurnal heating beneath very cold midlevel temperatures will continue to steepen low-level lapse rates amid strengthening low/mid-level winds. This environment will support locally damaging convective wind gusts (45-60 mph) through the afternoon -- especially with any small clusters/lines that can evolve. ...Four Corners into southern Colorado... Isolated high-based thunderstorms are expected across parts of the Four Corners and southern CO this afternoon, where midlevel moisture atop a diurnally deepening boundary layer will yield inverted-V profiles. As a result, a couple locally strong downbursts cannot be entirely ruled out. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0218 PM CDT Tue Apr 15 2025 Valid 161200Z - 171200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF EASTERN ARIZONA AND MUCH OF NEW MEXICO... ...Southwest... An approaching upper-level trough will provide increasing southwest flow aloft atop a very dry boundary layer over the Desert Southwest region. Relative humidity should drop below 10 percent across much of the lowland areas of southeastern Arizona/Southwestern New Mexico during peak heating along with widespread 10-15 percent RH spread across the area by tomorrow afternoon. Expanded Critical and Elevated highlights due to higher confidence indicated from latest model guidance consensus. ...Central High Plains... Elevated mid-level westerly flow will promote downslope drying and surface wind speeds of 15-20 mph across portions of southeastern Wyoming and western Nebraska. Minimal precipitation in the area over the last few days has allowed finer dormant/dead fuels to remain receptive. Added area of Elevated fire weather conditions to reflect overall fire weather threat. ..Williams/Moore.. 04/15/2025 .PREV DISCUSSION... /ISSUED 0130 AM CDT Tue Apr 15 2025/ ...Synopsis... An upper low off the southern California coast will begin to phase with a trough within the Northwest. Strong mid-level winds will develop over the Southwest by late afternoon. A surface low will deepen near the Colorado/Kansas border. ...Southwest... A broad area of elevated to critical fire weather is expected from southern/eastern Arizona into much of New Mexico and parts of southeast Colorado. Strong mid-level winds and the deepening surface low will combine to promote 15-25 mph surface winds (highest in terrain-favored areas). Critical fire weather is most likely to occur from southeast Arizona into southwest/west-central New Mexico. Here, strong winds will combine with areas of 5-15% RH. Elsewhere within the region, combinations of weaker winds and slightly higher RH (10-20%) will preclude critical highlights. ...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 0218 PM CDT Tue Apr 15 2025 Valid 161200Z - 171200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF EASTERN ARIZONA AND MUCH OF NEW MEXICO... ...Southwest... An approaching upper-level trough will provide increasing southwest flow aloft atop a very dry boundary layer over the Desert Southwest region. Relative humidity should drop below 10 percent across much of the lowland areas of southeastern Arizona/Southwestern New Mexico during peak heating along with widespread 10-15 percent RH spread across the area by tomorrow afternoon. Expanded Critical and Elevated highlights due to higher confidence indicated from latest model guidance consensus. ...Central High Plains... Elevated mid-level westerly flow will promote downslope drying and surface wind speeds of 15-20 mph across portions of southeastern Wyoming and western Nebraska. Minimal precipitation in the area over the last few days has allowed finer dormant/dead fuels to remain receptive. Added area of Elevated fire weather conditions to reflect overall fire weather threat. ..Williams/Moore.. 04/15/2025 .PREV DISCUSSION... /ISSUED 0130 AM CDT Tue Apr 15 2025/ ...Synopsis... An upper low off the southern California coast will begin to phase with a trough within the Northwest. Strong mid-level winds will develop over the Southwest by late afternoon. A surface low will deepen near the Colorado/Kansas border. ...Southwest... A broad area of elevated to critical fire weather is expected from southern/eastern Arizona into much of New Mexico and parts of southeast Colorado. Strong mid-level winds and the deepening surface low will combine to promote 15-25 mph surface winds (highest in terrain-favored areas). Critical fire weather is most likely to occur from southeast Arizona into southwest/west-central New Mexico. Here, strong winds will combine with areas of 5-15% RH. Elsewhere within the region, combinations of weaker winds and slightly higher RH (10-20%) will preclude critical highlights. ...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 0218 PM CDT Tue Apr 15 2025 Valid 161200Z - 171200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF EASTERN ARIZONA AND MUCH OF NEW MEXICO... ...Southwest... An approaching upper-level trough will provide increasing southwest flow aloft atop a very dry boundary layer over the Desert Southwest region. Relative humidity should drop below 10 percent across much of the lowland areas of southeastern Arizona/Southwestern New Mexico during peak heating along with widespread 10-15 percent RH spread across the area by tomorrow afternoon. Expanded Critical and Elevated highlights due to higher confidence indicated from latest model guidance consensus. ...Central High Plains... Elevated mid-level westerly flow will promote downslope drying and surface wind speeds of 15-20 mph across portions of southeastern Wyoming and western Nebraska. Minimal precipitation in the area over the last few days has allowed finer dormant/dead fuels to remain receptive. Added area of Elevated fire weather conditions to reflect overall fire weather threat. ..Williams/Moore.. 04/15/2025 .PREV DISCUSSION... /ISSUED 0130 AM CDT Tue Apr 15 2025/ ...Synopsis... An upper low off the southern California coast will begin to phase with a trough within the Northwest. Strong mid-level winds will develop over the Southwest by late afternoon. A surface low will deepen near the Colorado/Kansas border. ...Southwest... A broad area of elevated to critical fire weather is expected from southern/eastern Arizona into much of New Mexico and parts of southeast Colorado. Strong mid-level winds and the deepening surface low will combine to promote 15-25 mph surface winds (highest in terrain-favored areas). Critical fire weather is most likely to occur from southeast Arizona into southwest/west-central New Mexico. Here, strong winds will combine with areas of 5-15% RH. Elsewhere within the region, combinations of weaker winds and slightly higher RH (10-20%) will preclude critical highlights. ...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 0218 PM CDT Tue Apr 15 2025 Valid 161200Z - 171200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF EASTERN ARIZONA AND MUCH OF NEW MEXICO... ...Southwest... An approaching upper-level trough will provide increasing southwest flow aloft atop a very dry boundary layer over the Desert Southwest region. Relative humidity should drop below 10 percent across much of the lowland areas of southeastern Arizona/Southwestern New Mexico during peak heating along with widespread 10-15 percent RH spread across the area by tomorrow afternoon. Expanded Critical and Elevated highlights due to higher confidence indicated from latest model guidance consensus. ...Central High Plains... Elevated mid-level westerly flow will promote downslope drying and surface wind speeds of 15-20 mph across portions of southeastern Wyoming and western Nebraska. Minimal precipitation in the area over the last few days has allowed finer dormant/dead fuels to remain receptive. Added area of Elevated fire weather conditions to reflect overall fire weather threat. ..Williams/Moore.. 04/15/2025 .PREV DISCUSSION... /ISSUED 0130 AM CDT Tue Apr 15 2025/ ...Synopsis... An upper low off the southern California coast will begin to phase with a trough within the Northwest. Strong mid-level winds will develop over the Southwest by late afternoon. A surface low will deepen near the Colorado/Kansas border. ...Southwest... A broad area of elevated to critical fire weather is expected from southern/eastern Arizona into much of New Mexico and parts of southeast Colorado. Strong mid-level winds and the deepening surface low will combine to promote 15-25 mph surface winds (highest in terrain-favored areas). Critical fire weather is most likely to occur from southeast Arizona into southwest/west-central New Mexico. Here, strong winds will combine with areas of 5-15% RH. Elsewhere within the region, combinations of weaker winds and slightly higher RH (10-20%) will preclude critical highlights. ...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 0218 PM CDT Tue Apr 15 2025 Valid 161200Z - 171200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF EASTERN ARIZONA AND MUCH OF NEW MEXICO... ...Southwest... An approaching upper-level trough will provide increasing southwest flow aloft atop a very dry boundary layer over the Desert Southwest region. Relative humidity should drop below 10 percent across much of the lowland areas of southeastern Arizona/Southwestern New Mexico during peak heating along with widespread 10-15 percent RH spread across the area by tomorrow afternoon. Expanded Critical and Elevated highlights due to higher confidence indicated from latest model guidance consensus. ...Central High Plains... Elevated mid-level westerly flow will promote downslope drying and surface wind speeds of 15-20 mph across portions of southeastern Wyoming and western Nebraska. Minimal precipitation in the area over the last few days has allowed finer dormant/dead fuels to remain receptive. Added area of Elevated fire weather conditions to reflect overall fire weather threat. ..Williams/Moore.. 04/15/2025 .PREV DISCUSSION... /ISSUED 0130 AM CDT Tue Apr 15 2025/ ...Synopsis... An upper low off the southern California coast will begin to phase with a trough within the Northwest. Strong mid-level winds will develop over the Southwest by late afternoon. A surface low will deepen near the Colorado/Kansas border. ...Southwest... A broad area of elevated to critical fire weather is expected from southern/eastern Arizona into much of New Mexico and parts of southeast Colorado. Strong mid-level winds and the deepening surface low will combine to promote 15-25 mph surface winds (highest in terrain-favored areas). Critical fire weather is most likely to occur from southeast Arizona into southwest/west-central New Mexico. Here, strong winds will combine with areas of 5-15% RH. Elsewhere within the region, combinations of weaker winds and slightly higher RH (10-20%) will preclude critical highlights. ...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 0218 PM CDT Tue Apr 15 2025 Valid 161200Z - 171200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF EASTERN ARIZONA AND MUCH OF NEW MEXICO... ...Southwest... An approaching upper-level trough will provide increasing southwest flow aloft atop a very dry boundary layer over the Desert Southwest region. Relative humidity should drop below 10 percent across much of the lowland areas of southeastern Arizona/Southwestern New Mexico during peak heating along with widespread 10-15 percent RH spread across the area by tomorrow afternoon. Expanded Critical and Elevated highlights due to higher confidence indicated from latest model guidance consensus. ...Central High Plains... Elevated mid-level westerly flow will promote downslope drying and surface wind speeds of 15-20 mph across portions of southeastern Wyoming and western Nebraska. Minimal precipitation in the area over the last few days has allowed finer dormant/dead fuels to remain receptive. Added area of Elevated fire weather conditions to reflect overall fire weather threat. ..Williams/Moore.. 04/15/2025 .PREV DISCUSSION... /ISSUED 0130 AM CDT Tue Apr 15 2025/ ...Synopsis... An upper low off the southern California coast will begin to phase with a trough within the Northwest. Strong mid-level winds will develop over the Southwest by late afternoon. A surface low will deepen near the Colorado/Kansas border. ...Southwest... A broad area of elevated to critical fire weather is expected from southern/eastern Arizona into much of New Mexico and parts of southeast Colorado. Strong mid-level winds and the deepening surface low will combine to promote 15-25 mph surface winds (highest in terrain-favored areas). Critical fire weather is most likely to occur from southeast Arizona into southwest/west-central New Mexico. Here, strong winds will combine with areas of 5-15% RH. Elsewhere within the region, combinations of weaker winds and slightly higher RH (10-20%) will preclude critical highlights. ...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 0218 PM CDT Tue Apr 15 2025 Valid 161200Z - 171200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF EASTERN ARIZONA AND MUCH OF NEW MEXICO... ...Southwest... An approaching upper-level trough will provide increasing southwest flow aloft atop a very dry boundary layer over the Desert Southwest region. Relative humidity should drop below 10 percent across much of the lowland areas of southeastern Arizona/Southwestern New Mexico during peak heating along with widespread 10-15 percent RH spread across the area by tomorrow afternoon. Expanded Critical and Elevated highlights due to higher confidence indicated from latest model guidance consensus. ...Central High Plains... Elevated mid-level westerly flow will promote downslope drying and surface wind speeds of 15-20 mph across portions of southeastern Wyoming and western Nebraska. Minimal precipitation in the area over the last few days has allowed finer dormant/dead fuels to remain receptive. Added area of Elevated fire weather conditions to reflect overall fire weather threat. ..Williams/Moore.. 04/15/2025 .PREV DISCUSSION... /ISSUED 0130 AM CDT Tue Apr 15 2025/ ...Synopsis... An upper low off the southern California coast will begin to phase with a trough within the Northwest. Strong mid-level winds will develop over the Southwest by late afternoon. A surface low will deepen near the Colorado/Kansas border. ...Southwest... A broad area of elevated to critical fire weather is expected from southern/eastern Arizona into much of New Mexico and parts of southeast Colorado. Strong mid-level winds and the deepening surface low will combine to promote 15-25 mph surface winds (highest in terrain-favored areas). Critical fire weather is most likely to occur from southeast Arizona into southwest/west-central New Mexico. Here, strong winds will combine with areas of 5-15% RH. Elsewhere within the region, combinations of weaker winds and slightly higher RH (10-20%) will preclude critical highlights. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0204 PM CDT Tue Apr 15 2025 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IOWA...NORTHERN MISSOURI...EASTERN/CENTRAL NEBRASKA... ...SUMMARY... Scattered severe thunderstorms, with a primary threat of large hail, are possible on Thursday evening/night, centered on eastern/central Nebraska, northern Missouri, and Iowa. ...Synopsis... Large scale troughing is progged from portions of the Canadian Prairies into the Intermountain West and Great Basin on Thursday. A deepening surface low will shift eastward across the northern central/high Plains, with a dryline extending from southern Nebraska into central Kansas and Oklahoma. A triple point formed by a secondary surface low circulation, dryline, and a frontal boundary/modified outflow in central Nebraska will be the focus of additional development by the late afternoon/evening across central/eastern Nebraska. ...Iowa, Nebraska, Missouri... Elevated thunderstorm activity is expected to be ongoing at the beginning of the D3 period across portions of eastern Nebraska into western Iowa and Missouri. Some instances of severe hail will be possible with this activity. Moisture return will be ongoing through much of the day, with upper 50s to 60s dew points from central Nebraska into Iowa, eastern Kansas, and western Missouri. Additional development is expected late afternoon into the early evening across the aforementioned triple point in central Nebraska. Daytime heating and moisture return will yield MLCAPE around 1500-2000 J/kg amid steep low to mid-level lapse rates and ample deep layer shear. This environment will support supercells, some of which may be initially surface based and capable of very large hail and damaging wind. Further east across Iowa and northern Missouri, MLCIN will be in place behind morning convection. Cells may become elevated with eastward movement, but will still pose potential for large hail and damaging wind. The Slight was expanded westward into Nebraska to support this potential. Storms will continue into portions of western Illinois through the end of the period. ..Thornton/Leitman.. 04/15/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0204 PM CDT Tue Apr 15 2025 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IOWA...NORTHERN MISSOURI...EASTERN/CENTRAL NEBRASKA... ...SUMMARY... Scattered severe thunderstorms, with a primary threat of large hail, are possible on Thursday evening/night, centered on eastern/central Nebraska, northern Missouri, and Iowa. ...Synopsis... Large scale troughing is progged from portions of the Canadian Prairies into the Intermountain West and Great Basin on Thursday. A deepening surface low will shift eastward across the northern central/high Plains, with a dryline extending from southern Nebraska into central Kansas and Oklahoma. A triple point formed by a secondary surface low circulation, dryline, and a frontal boundary/modified outflow in central Nebraska will be the focus of additional development by the late afternoon/evening across central/eastern Nebraska. ...Iowa, Nebraska, Missouri... Elevated thunderstorm activity is expected to be ongoing at the beginning of the D3 period across portions of eastern Nebraska into western Iowa and Missouri. Some instances of severe hail will be possible with this activity. Moisture return will be ongoing through much of the day, with upper 50s to 60s dew points from central Nebraska into Iowa, eastern Kansas, and western Missouri. Additional development is expected late afternoon into the early evening across the aforementioned triple point in central Nebraska. Daytime heating and moisture return will yield MLCAPE around 1500-2000 J/kg amid steep low to mid-level lapse rates and ample deep layer shear. This environment will support supercells, some of which may be initially surface based and capable of very large hail and damaging wind. Further east across Iowa and northern Missouri, MLCIN will be in place behind morning convection. Cells may become elevated with eastward movement, but will still pose potential for large hail and damaging wind. The Slight was expanded westward into Nebraska to support this potential. Storms will continue into portions of western Illinois through the end of the period. ..Thornton/Leitman.. 04/15/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0204 PM CDT Tue Apr 15 2025 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IOWA...NORTHERN MISSOURI...EASTERN/CENTRAL NEBRASKA... ...SUMMARY... Scattered severe thunderstorms, with a primary threat of large hail, are possible on Thursday evening/night, centered on eastern/central Nebraska, northern Missouri, and Iowa. ...Synopsis... Large scale troughing is progged from portions of the Canadian Prairies into the Intermountain West and Great Basin on Thursday. A deepening surface low will shift eastward across the northern central/high Plains, with a dryline extending from southern Nebraska into central Kansas and Oklahoma. A triple point formed by a secondary surface low circulation, dryline, and a frontal boundary/modified outflow in central Nebraska will be the focus of additional development by the late afternoon/evening across central/eastern Nebraska. ...Iowa, Nebraska, Missouri... Elevated thunderstorm activity is expected to be ongoing at the beginning of the D3 period across portions of eastern Nebraska into western Iowa and Missouri. Some instances of severe hail will be possible with this activity. Moisture return will be ongoing through much of the day, with upper 50s to 60s dew points from central Nebraska into Iowa, eastern Kansas, and western Missouri. Additional development is expected late afternoon into the early evening across the aforementioned triple point in central Nebraska. Daytime heating and moisture return will yield MLCAPE around 1500-2000 J/kg amid steep low to mid-level lapse rates and ample deep layer shear. This environment will support supercells, some of which may be initially surface based and capable of very large hail and damaging wind. Further east across Iowa and northern Missouri, MLCIN will be in place behind morning convection. Cells may become elevated with eastward movement, but will still pose potential for large hail and damaging wind. The Slight was expanded westward into Nebraska to support this potential. Storms will continue into portions of western Illinois through the end of the period. ..Thornton/Leitman.. 04/15/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0204 PM CDT Tue Apr 15 2025 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IOWA...NORTHERN MISSOURI...EASTERN/CENTRAL NEBRASKA... ...SUMMARY... Scattered severe thunderstorms, with a primary threat of large hail, are possible on Thursday evening/night, centered on eastern/central Nebraska, northern Missouri, and Iowa. ...Synopsis... Large scale troughing is progged from portions of the Canadian Prairies into the Intermountain West and Great Basin on Thursday. A deepening surface low will shift eastward across the northern central/high Plains, with a dryline extending from southern Nebraska into central Kansas and Oklahoma. A triple point formed by a secondary surface low circulation, dryline, and a frontal boundary/modified outflow in central Nebraska will be the focus of additional development by the late afternoon/evening across central/eastern Nebraska. ...Iowa, Nebraska, Missouri... Elevated thunderstorm activity is expected to be ongoing at the beginning of the D3 period across portions of eastern Nebraska into western Iowa and Missouri. Some instances of severe hail will be possible with this activity. Moisture return will be ongoing through much of the day, with upper 50s to 60s dew points from central Nebraska into Iowa, eastern Kansas, and western Missouri. Additional development is expected late afternoon into the early evening across the aforementioned triple point in central Nebraska. Daytime heating and moisture return will yield MLCAPE around 1500-2000 J/kg amid steep low to mid-level lapse rates and ample deep layer shear. This environment will support supercells, some of which may be initially surface based and capable of very large hail and damaging wind. Further east across Iowa and northern Missouri, MLCIN will be in place behind morning convection. Cells may become elevated with eastward movement, but will still pose potential for large hail and damaging wind. The Slight was expanded westward into Nebraska to support this potential. Storms will continue into portions of western Illinois through the end of the period. ..Thornton/Leitman.. 04/15/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0204 PM CDT Tue Apr 15 2025 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IOWA...NORTHERN MISSOURI...EASTERN/CENTRAL NEBRASKA... ...SUMMARY... Scattered severe thunderstorms, with a primary threat of large hail, are possible on Thursday evening/night, centered on eastern/central Nebraska, northern Missouri, and Iowa. ...Synopsis... Large scale troughing is progged from portions of the Canadian Prairies into the Intermountain West and Great Basin on Thursday. A deepening surface low will shift eastward across the northern central/high Plains, with a dryline extending from southern Nebraska into central Kansas and Oklahoma. A triple point formed by a secondary surface low circulation, dryline, and a frontal boundary/modified outflow in central Nebraska will be the focus of additional development by the late afternoon/evening across central/eastern Nebraska. ...Iowa, Nebraska, Missouri... Elevated thunderstorm activity is expected to be ongoing at the beginning of the D3 period across portions of eastern Nebraska into western Iowa and Missouri. Some instances of severe hail will be possible with this activity. Moisture return will be ongoing through much of the day, with upper 50s to 60s dew points from central Nebraska into Iowa, eastern Kansas, and western Missouri. Additional development is expected late afternoon into the early evening across the aforementioned triple point in central Nebraska. Daytime heating and moisture return will yield MLCAPE around 1500-2000 J/kg amid steep low to mid-level lapse rates and ample deep layer shear. This environment will support supercells, some of which may be initially surface based and capable of very large hail and damaging wind. Further east across Iowa and northern Missouri, MLCIN will be in place behind morning convection. Cells may become elevated with eastward movement, but will still pose potential for large hail and damaging wind. The Slight was expanded westward into Nebraska to support this potential. Storms will continue into portions of western Illinois through the end of the period. ..Thornton/Leitman.. 04/15/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0204 PM CDT Tue Apr 15 2025 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IOWA...NORTHERN MISSOURI...EASTERN/CENTRAL NEBRASKA... ...SUMMARY... Scattered severe thunderstorms, with a primary threat of large hail, are possible on Thursday evening/night, centered on eastern/central Nebraska, northern Missouri, and Iowa. ...Synopsis... Large scale troughing is progged from portions of the Canadian Prairies into the Intermountain West and Great Basin on Thursday. A deepening surface low will shift eastward across the northern central/high Plains, with a dryline extending from southern Nebraska into central Kansas and Oklahoma. A triple point formed by a secondary surface low circulation, dryline, and a frontal boundary/modified outflow in central Nebraska will be the focus of additional development by the late afternoon/evening across central/eastern Nebraska. ...Iowa, Nebraska, Missouri... Elevated thunderstorm activity is expected to be ongoing at the beginning of the D3 period across portions of eastern Nebraska into western Iowa and Missouri. Some instances of severe hail will be possible with this activity. Moisture return will be ongoing through much of the day, with upper 50s to 60s dew points from central Nebraska into Iowa, eastern Kansas, and western Missouri. Additional development is expected late afternoon into the early evening across the aforementioned triple point in central Nebraska. Daytime heating and moisture return will yield MLCAPE around 1500-2000 J/kg amid steep low to mid-level lapse rates and ample deep layer shear. This environment will support supercells, some of which may be initially surface based and capable of very large hail and damaging wind. Further east across Iowa and northern Missouri, MLCIN will be in place behind morning convection. Cells may become elevated with eastward movement, but will still pose potential for large hail and damaging wind. The Slight was expanded westward into Nebraska to support this potential. Storms will continue into portions of western Illinois through the end of the period. ..Thornton/Leitman.. 04/15/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0204 PM CDT Tue Apr 15 2025 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IOWA...NORTHERN MISSOURI...EASTERN/CENTRAL NEBRASKA... ...SUMMARY... Scattered severe thunderstorms, with a primary threat of large hail, are possible on Thursday evening/night, centered on eastern/central Nebraska, northern Missouri, and Iowa. ...Synopsis... Large scale troughing is progged from portions of the Canadian Prairies into the Intermountain West and Great Basin on Thursday. A deepening surface low will shift eastward across the northern central/high Plains, with a dryline extending from southern Nebraska into central Kansas and Oklahoma. A triple point formed by a secondary surface low circulation, dryline, and a frontal boundary/modified outflow in central Nebraska will be the focus of additional development by the late afternoon/evening across central/eastern Nebraska. ...Iowa, Nebraska, Missouri... Elevated thunderstorm activity is expected to be ongoing at the beginning of the D3 period across portions of eastern Nebraska into western Iowa and Missouri. Some instances of severe hail will be possible with this activity. Moisture return will be ongoing through much of the day, with upper 50s to 60s dew points from central Nebraska into Iowa, eastern Kansas, and western Missouri. Additional development is expected late afternoon into the early evening across the aforementioned triple point in central Nebraska. Daytime heating and moisture return will yield MLCAPE around 1500-2000 J/kg amid steep low to mid-level lapse rates and ample deep layer shear. This environment will support supercells, some of which may be initially surface based and capable of very large hail and damaging wind. Further east across Iowa and northern Missouri, MLCIN will be in place behind morning convection. Cells may become elevated with eastward movement, but will still pose potential for large hail and damaging wind. The Slight was expanded westward into Nebraska to support this potential. Storms will continue into portions of western Illinois through the end of the period. ..Thornton/Leitman.. 04/15/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0204 PM CDT Tue Apr 15 2025 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IOWA...NORTHERN MISSOURI...EASTERN/CENTRAL NEBRASKA... ...SUMMARY... Scattered severe thunderstorms, with a primary threat of large hail, are possible on Thursday evening/night, centered on eastern/central Nebraska, northern Missouri, and Iowa. ...Synopsis... Large scale troughing is progged from portions of the Canadian Prairies into the Intermountain West and Great Basin on Thursday. A deepening surface low will shift eastward across the northern central/high Plains, with a dryline extending from southern Nebraska into central Kansas and Oklahoma. A triple point formed by a secondary surface low circulation, dryline, and a frontal boundary/modified outflow in central Nebraska will be the focus of additional development by the late afternoon/evening across central/eastern Nebraska. ...Iowa, Nebraska, Missouri... Elevated thunderstorm activity is expected to be ongoing at the beginning of the D3 period across portions of eastern Nebraska into western Iowa and Missouri. Some instances of severe hail will be possible with this activity. Moisture return will be ongoing through much of the day, with upper 50s to 60s dew points from central Nebraska into Iowa, eastern Kansas, and western Missouri. Additional development is expected late afternoon into the early evening across the aforementioned triple point in central Nebraska. Daytime heating and moisture return will yield MLCAPE around 1500-2000 J/kg amid steep low to mid-level lapse rates and ample deep layer shear. This environment will support supercells, some of which may be initially surface based and capable of very large hail and damaging wind. Further east across Iowa and northern Missouri, MLCIN will be in place behind morning convection. Cells may become elevated with eastward movement, but will still pose potential for large hail and damaging wind. The Slight was expanded westward into Nebraska to support this potential. Storms will continue into portions of western Illinois through the end of the period. ..Thornton/Leitman.. 04/15/2025 Read more

MD 0453 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PARTS OF NRN PA...SRN NY
Mesoscale Discussion 0453 NWS Storm Prediction Center Norman OK 1108 AM CDT Tue Apr 15 2025 Areas affected...parts of nrn PA...srn NY Concerning...Severe potential...Watch unlikely Valid 151608Z - 151915Z Probability of Watch Issuance...5 percent SUMMARY...Showers and embedded thunderstorms accompanied by gusty winds occasionally approaching or briefly exceeding severe limits are possible into the 2-4 PM EDT time frame, particularly in a corridor across north central Pennsylvania toward the Catskills and Poconos. DISCUSSION...Boundary-layer destabilization is ongoing within a narrow corridor across the upper Ohio Valley into lower Great Lakes region. This is generally focused beneath the leading of stronger mid-level forcing for ascent and cooling associated with large-scale troughing overspreading the region. Thermodynamic profiles have become increasingly conducive to the initiation of scattered low-topped thunderstorm activity, and this probably will continue this afternoon with further boundary-layer warming and mixing with insolation. The last Rapid Refresh suggests that the corridor of stronger mid-level cooling and weak boundary-layer destabilization will gradually shift east-northeastward across northern Pennsylvania and southern New York State through 18-20Z. This may include CAPE increasing only to the order of a couple hundred J/kg for a seasonably cool boundary layer. However, steepening low-level lapse rates, with profiles characterized by modest temperature/dew point spreads, will contribute to sub-cloud evaporative cooling and melting, and aid downward transfer of momentum associated with strengthening westerly flow (on the order of 30-40 kt) in the 850-700 mb layer. ..Kerr/Guyer.. 04/15/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...ALY...BGM...BUF...CTP...PBZ... LAT...LON 42837591 43187450 42547412 42027412 40927731 41097943 42207838 42837591 MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1223 PM CDT Tue Apr 15 2025 Valid 161200Z - 171200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS PORTIONS OF THE CENTRAL GREAT PLAINS... ...SUMMARY... Isolated severe thunderstorms, with a primary threat of large hail, are possible on Wednesday evening/night across parts of the central Great Plains. ...Synopsis... A progressive open wave trough will shift southward from Canada before phasing with an upper-level low off the west coast of California on Wednesday. The subtropical jet will spread eastward across the central Plains, with several embedded shortwave disturbances rippling through the flow. Westerly flow across the central/southern Rockies will promote lee cyclogenesis late in the period, with an increase in a southerly low-level jet across the southern/central Plains. ...Central Great Plains... Southerly return flow will bring an increase of moisture into the central Plains, with potential for isolated to scattered thunderstorm development. A limiting factor remains increasing CIN and low-level stability beneath a strong EML. Regardless, agreement has increased on convective initiation occurring near the dryline across portions of central/southern Kansas late in the period. Given the elevated nature of this convection, the greatest risk will be for large hail. This will continue into the lower MO Valley through the end of the period Thursday morning. Earlier in the period, some potential exists for development further south near the OK/KS border toward the end of peak heating in the early evening. A few hi-res solutions have hinted at development of a supercell or two within this region, apparent in UH tracks from the 12z HREF. Conditionally, an established supercell in this region could support very large hail, given steep lapse rates aloft and ample shear/CAPE. ...Elsewhere... Isolated to scattered thunderstorms are expected from northern/central California into the Great Basin and northern Rockies through the period. These are expected to be sub-severe given weak shear profiles. ..Thornton/Leitman.. 04/15/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1223 PM CDT Tue Apr 15 2025 Valid 161200Z - 171200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS PORTIONS OF THE CENTRAL GREAT PLAINS... ...SUMMARY... Isolated severe thunderstorms, with a primary threat of large hail, are possible on Wednesday evening/night across parts of the central Great Plains. ...Synopsis... A progressive open wave trough will shift southward from Canada before phasing with an upper-level low off the west coast of California on Wednesday. The subtropical jet will spread eastward across the central Plains, with several embedded shortwave disturbances rippling through the flow. Westerly flow across the central/southern Rockies will promote lee cyclogenesis late in the period, with an increase in a southerly low-level jet across the southern/central Plains. ...Central Great Plains... Southerly return flow will bring an increase of moisture into the central Plains, with potential for isolated to scattered thunderstorm development. A limiting factor remains increasing CIN and low-level stability beneath a strong EML. Regardless, agreement has increased on convective initiation occurring near the dryline across portions of central/southern Kansas late in the period. Given the elevated nature of this convection, the greatest risk will be for large hail. This will continue into the lower MO Valley through the end of the period Thursday morning. Earlier in the period, some potential exists for development further south near the OK/KS border toward the end of peak heating in the early evening. A few hi-res solutions have hinted at development of a supercell or two within this region, apparent in UH tracks from the 12z HREF. Conditionally, an established supercell in this region could support very large hail, given steep lapse rates aloft and ample shear/CAPE. ...Elsewhere... Isolated to scattered thunderstorms are expected from northern/central California into the Great Basin and northern Rockies through the period. These are expected to be sub-severe given weak shear profiles. ..Thornton/Leitman.. 04/15/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1223 PM CDT Tue Apr 15 2025 Valid 161200Z - 171200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS PORTIONS OF THE CENTRAL GREAT PLAINS... ...SUMMARY... Isolated severe thunderstorms, with a primary threat of large hail, are possible on Wednesday evening/night across parts of the central Great Plains. ...Synopsis... A progressive open wave trough will shift southward from Canada before phasing with an upper-level low off the west coast of California on Wednesday. The subtropical jet will spread eastward across the central Plains, with several embedded shortwave disturbances rippling through the flow. Westerly flow across the central/southern Rockies will promote lee cyclogenesis late in the period, with an increase in a southerly low-level jet across the southern/central Plains. ...Central Great Plains... Southerly return flow will bring an increase of moisture into the central Plains, with potential for isolated to scattered thunderstorm development. A limiting factor remains increasing CIN and low-level stability beneath a strong EML. Regardless, agreement has increased on convective initiation occurring near the dryline across portions of central/southern Kansas late in the period. Given the elevated nature of this convection, the greatest risk will be for large hail. This will continue into the lower MO Valley through the end of the period Thursday morning. Earlier in the period, some potential exists for development further south near the OK/KS border toward the end of peak heating in the early evening. A few hi-res solutions have hinted at development of a supercell or two within this region, apparent in UH tracks from the 12z HREF. Conditionally, an established supercell in this region could support very large hail, given steep lapse rates aloft and ample shear/CAPE. ...Elsewhere... Isolated to scattered thunderstorms are expected from northern/central California into the Great Basin and northern Rockies through the period. These are expected to be sub-severe given weak shear profiles. ..Thornton/Leitman.. 04/15/2025 Read more