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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0151 AM CDT Tue Apr 30 2024 Valid 011200Z - 021200Z ...CRITICAL FIRE WEATHER AREA FOR PARTS OF THE SOUTHERN HIGH PLAINS... ...Synopsis... Dry and breezy conditions are expected across the southern High Plains on Wednesday in response to a development of a lee cyclone, as increasing mid-level flow overspreads the Rockies. Deeply mixed profiles by the afternoon will yield single-digit relative humidity amid sustained winds 20 to 25 mph across portions of eastern New Mexico into the northern Texas Panhandle. Little recent rainfall across this area has sufficiently dried fuels, with ERCs forecast to be in the 75th percentile. This will support Critical fire weather concerns, with broader Elevated fire weather concerns extending into southeastern Colorado and the western Oklahoma Panhandle. ..Thornton.. 04/30/2024 ...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 0151 AM CDT Tue Apr 30 2024 Valid 011200Z - 021200Z ...CRITICAL FIRE WEATHER AREA FOR PARTS OF THE SOUTHERN HIGH PLAINS... ...Synopsis... Dry and breezy conditions are expected across the southern High Plains on Wednesday in response to a development of a lee cyclone, as increasing mid-level flow overspreads the Rockies. Deeply mixed profiles by the afternoon will yield single-digit relative humidity amid sustained winds 20 to 25 mph across portions of eastern New Mexico into the northern Texas Panhandle. Little recent rainfall across this area has sufficiently dried fuels, with ERCs forecast to be in the 75th percentile. This will support Critical fire weather concerns, with broader Elevated fire weather concerns extending into southeastern Colorado and the western Oklahoma Panhandle. ..Thornton.. 04/30/2024 ...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 0151 AM CDT Tue Apr 30 2024 Valid 011200Z - 021200Z ...CRITICAL FIRE WEATHER AREA FOR PARTS OF THE SOUTHERN HIGH PLAINS... ...Synopsis... Dry and breezy conditions are expected across the southern High Plains on Wednesday in response to a development of a lee cyclone, as increasing mid-level flow overspreads the Rockies. Deeply mixed profiles by the afternoon will yield single-digit relative humidity amid sustained winds 20 to 25 mph across portions of eastern New Mexico into the northern Texas Panhandle. Little recent rainfall across this area has sufficiently dried fuels, with ERCs forecast to be in the 75th percentile. This will support Critical fire weather concerns, with broader Elevated fire weather concerns extending into southeastern Colorado and the western Oklahoma Panhandle. ..Thornton.. 04/30/2024 ...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 0151 AM CDT Tue Apr 30 2024 Valid 011200Z - 021200Z ...CRITICAL FIRE WEATHER AREA FOR PARTS OF THE SOUTHERN HIGH PLAINS... ...Synopsis... Dry and breezy conditions are expected across the southern High Plains on Wednesday in response to a development of a lee cyclone, as increasing mid-level flow overspreads the Rockies. Deeply mixed profiles by the afternoon will yield single-digit relative humidity amid sustained winds 20 to 25 mph across portions of eastern New Mexico into the northern Texas Panhandle. Little recent rainfall across this area has sufficiently dried fuels, with ERCs forecast to be in the 75th percentile. This will support Critical fire weather concerns, with broader Elevated fire weather concerns extending into southeastern Colorado and the western Oklahoma Panhandle. ..Thornton.. 04/30/2024 ...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 0110 AM CDT Tue Apr 30 2024 Valid 301200Z - 011200Z ...Synopsis... A belt of enhanced mid-level flow will spread across the Northern Rockies from an upper low across the northwestern US today. A cold frontal passage will bring rainfall across much of eastern Montana and Wyoming this morning. Behind the cold front, a dry continental air mass will overspread this region into the western Dakotas, with relative humidity dropping as low as 15 percent amid sustained winds 20-25 mph. Fuels within southern Montana into the western Dakotas, where less rainfall is forecast, are sufficiently dry to carry risk of Elevated fire weather concerns. ..Thornton.. 04/30/2024 ...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 0110 AM CDT Tue Apr 30 2024 Valid 301200Z - 011200Z ...Synopsis... A belt of enhanced mid-level flow will spread across the Northern Rockies from an upper low across the northwestern US today. A cold frontal passage will bring rainfall across much of eastern Montana and Wyoming this morning. Behind the cold front, a dry continental air mass will overspread this region into the western Dakotas, with relative humidity dropping as low as 15 percent amid sustained winds 20-25 mph. Fuels within southern Montana into the western Dakotas, where less rainfall is forecast, are sufficiently dry to carry risk of Elevated fire weather concerns. ..Thornton.. 04/30/2024 ...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 0110 AM CDT Tue Apr 30 2024 Valid 301200Z - 011200Z ...Synopsis... A belt of enhanced mid-level flow will spread across the Northern Rockies from an upper low across the northwestern US today. A cold frontal passage will bring rainfall across much of eastern Montana and Wyoming this morning. Behind the cold front, a dry continental air mass will overspread this region into the western Dakotas, with relative humidity dropping as low as 15 percent amid sustained winds 20-25 mph. Fuels within southern Montana into the western Dakotas, where less rainfall is forecast, are sufficiently dry to carry risk of Elevated fire weather concerns. ..Thornton.. 04/30/2024 ...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 0110 AM CDT Tue Apr 30 2024 Valid 301200Z - 011200Z ...Synopsis... A belt of enhanced mid-level flow will spread across the Northern Rockies from an upper low across the northwestern US today. A cold frontal passage will bring rainfall across much of eastern Montana and Wyoming this morning. Behind the cold front, a dry continental air mass will overspread this region into the western Dakotas, with relative humidity dropping as low as 15 percent amid sustained winds 20-25 mph. Fuels within southern Montana into the western Dakotas, where less rainfall is forecast, are sufficiently dry to carry risk of Elevated fire weather concerns. ..Thornton.. 04/30/2024 ...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 1249 AM CDT Tue Apr 30 2024 Valid 011200Z - 021200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER THE CENTRAL PLAINS...WITH SCATTERED SEVERE STORMS FROM WESTERN TEXAS INTO SOUTHERN NEBRASKA... ...SUMMARY... Scattered severe thunderstorms will be possible across parts of the central and southern Plains on Wednesday. A few tornadoes (including potential for a strong tornado), very large hail and damaging winds are expected. ...Synopsis... On Wednesday, an upper trough will extend from MT into the Great Basin by late afternoon, with increasing west/southwest flow aloft spreading into the central and northern Plains. Height falls with this trough will occur mainly overnight and into Thursday morning over the Plains, with 500 mb southwesterlies increasing all the while. Farther south, modest midlevel westerlies will exist from western TX into northern Mexico, the upper-level winds more prominent at over 60 kt at 300 mb. At the surface, low pressure will deepen over the central High Plains in advance of the upper trough, with a warm front lifting north across KS during the day. This front will reach into far southern NE during the late evening and overnight, with 60s F dewpoints possibly reaching I-80 into eastern NE by 12Z Thursday. Backed surface winds north of the warm front will also lead to rising dewpoints into western KS and far eastern CO toward the low, while robust moisture builds east of the dryline from southwest KS into western TX. Aiding both moisture advection and shear will be an increasing low-level jet which will exceed 50 kt Wednesday evening, affecting the majority of the central and southern Plains. Finally, a cold front will move into western NE and KS by around 06Z, and surge east toward the MO Valley into Thursday morning, augmented with thunderstorm outflow. ...Central Plains... Several possible severe-weather regimes may occur Wednesday into Wednesday night, with initial activity expected along the warm front during the day from south-central into eastern KS. This early activity will begin elevated, but instability may be strong and support occasional hail. With time, additional activity could develop along any outflow boundaries as theta-e advection persists, and a few surface-based cells may result by afternoon with hail or tornado risk. Later in the day and coincident with peak heating, widely spaced supercells are anticipated along the dryline from western KS into northwest TX. Given that this area will be well ahead of the upper trough, large-scale support will be minimal. However, strong heating and mid to upper 60s F dewpoints will still lead to at least isolated supercells capable of very large hail, and tornado risk within a relatively narrow zone. Farther north, the plume of backed moisture may lead to storms developing over eastern CO into western KS. This convection will eventually interact with the cold front by late evening. Depending on how uncapped the air mass is at that time, cells may congeal into a line of storms, which will be limited on the northern end by cooler air into NE, and on the southern end by possible capping. However, with very steep lapse rates aloft, a strong low-level jet and the frontal forcing, a few significant wind gusts cannot be ruled out along the NE/KS border overnight. ...Western TX... Strong heating will occur near the dryline, where an uncapped and very unstable air mass will develop. As dewpoints rise well into the 60s F, MLCAPE may exceed 4000 J/kg. Ample low-level convergence along the boundary will lead to scattered afternoon storms, some of which will be slow-moving supercells. Increasing and backing 850 mb winds with time may support a few east/southeast cell motions, with localized very large hail. In addition, hail-laden outflows may lead to wind damage. ..Jewell.. 04/30/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1249 AM CDT Tue Apr 30 2024 Valid 011200Z - 021200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER THE CENTRAL PLAINS...WITH SCATTERED SEVERE STORMS FROM WESTERN TEXAS INTO SOUTHERN NEBRASKA... ...SUMMARY... Scattered severe thunderstorms will be possible across parts of the central and southern Plains on Wednesday. A few tornadoes (including potential for a strong tornado), very large hail and damaging winds are expected. ...Synopsis... On Wednesday, an upper trough will extend from MT into the Great Basin by late afternoon, with increasing west/southwest flow aloft spreading into the central and northern Plains. Height falls with this trough will occur mainly overnight and into Thursday morning over the Plains, with 500 mb southwesterlies increasing all the while. Farther south, modest midlevel westerlies will exist from western TX into northern Mexico, the upper-level winds more prominent at over 60 kt at 300 mb. At the surface, low pressure will deepen over the central High Plains in advance of the upper trough, with a warm front lifting north across KS during the day. This front will reach into far southern NE during the late evening and overnight, with 60s F dewpoints possibly reaching I-80 into eastern NE by 12Z Thursday. Backed surface winds north of the warm front will also lead to rising dewpoints into western KS and far eastern CO toward the low, while robust moisture builds east of the dryline from southwest KS into western TX. Aiding both moisture advection and shear will be an increasing low-level jet which will exceed 50 kt Wednesday evening, affecting the majority of the central and southern Plains. Finally, a cold front will move into western NE and KS by around 06Z, and surge east toward the MO Valley into Thursday morning, augmented with thunderstorm outflow. ...Central Plains... Several possible severe-weather regimes may occur Wednesday into Wednesday night, with initial activity expected along the warm front during the day from south-central into eastern KS. This early activity will begin elevated, but instability may be strong and support occasional hail. With time, additional activity could develop along any outflow boundaries as theta-e advection persists, and a few surface-based cells may result by afternoon with hail or tornado risk. Later in the day and coincident with peak heating, widely spaced supercells are anticipated along the dryline from western KS into northwest TX. Given that this area will be well ahead of the upper trough, large-scale support will be minimal. However, strong heating and mid to upper 60s F dewpoints will still lead to at least isolated supercells capable of very large hail, and tornado risk within a relatively narrow zone. Farther north, the plume of backed moisture may lead to storms developing over eastern CO into western KS. This convection will eventually interact with the cold front by late evening. Depending on how uncapped the air mass is at that time, cells may congeal into a line of storms, which will be limited on the northern end by cooler air into NE, and on the southern end by possible capping. However, with very steep lapse rates aloft, a strong low-level jet and the frontal forcing, a few significant wind gusts cannot be ruled out along the NE/KS border overnight. ...Western TX... Strong heating will occur near the dryline, where an uncapped and very unstable air mass will develop. As dewpoints rise well into the 60s F, MLCAPE may exceed 4000 J/kg. Ample low-level convergence along the boundary will lead to scattered afternoon storms, some of which will be slow-moving supercells. Increasing and backing 850 mb winds with time may support a few east/southeast cell motions, with localized very large hail. In addition, hail-laden outflows may lead to wind damage. ..Jewell.. 04/30/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1249 AM CDT Tue Apr 30 2024 Valid 011200Z - 021200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER THE CENTRAL PLAINS...WITH SCATTERED SEVERE STORMS FROM WESTERN TEXAS INTO SOUTHERN NEBRASKA... ...SUMMARY... Scattered severe thunderstorms will be possible across parts of the central and southern Plains on Wednesday. A few tornadoes (including potential for a strong tornado), very large hail and damaging winds are expected. ...Synopsis... On Wednesday, an upper trough will extend from MT into the Great Basin by late afternoon, with increasing west/southwest flow aloft spreading into the central and northern Plains. Height falls with this trough will occur mainly overnight and into Thursday morning over the Plains, with 500 mb southwesterlies increasing all the while. Farther south, modest midlevel westerlies will exist from western TX into northern Mexico, the upper-level winds more prominent at over 60 kt at 300 mb. At the surface, low pressure will deepen over the central High Plains in advance of the upper trough, with a warm front lifting north across KS during the day. This front will reach into far southern NE during the late evening and overnight, with 60s F dewpoints possibly reaching I-80 into eastern NE by 12Z Thursday. Backed surface winds north of the warm front will also lead to rising dewpoints into western KS and far eastern CO toward the low, while robust moisture builds east of the dryline from southwest KS into western TX. Aiding both moisture advection and shear will be an increasing low-level jet which will exceed 50 kt Wednesday evening, affecting the majority of the central and southern Plains. Finally, a cold front will move into western NE and KS by around 06Z, and surge east toward the MO Valley into Thursday morning, augmented with thunderstorm outflow. ...Central Plains... Several possible severe-weather regimes may occur Wednesday into Wednesday night, with initial activity expected along the warm front during the day from south-central into eastern KS. This early activity will begin elevated, but instability may be strong and support occasional hail. With time, additional activity could develop along any outflow boundaries as theta-e advection persists, and a few surface-based cells may result by afternoon with hail or tornado risk. Later in the day and coincident with peak heating, widely spaced supercells are anticipated along the dryline from western KS into northwest TX. Given that this area will be well ahead of the upper trough, large-scale support will be minimal. However, strong heating and mid to upper 60s F dewpoints will still lead to at least isolated supercells capable of very large hail, and tornado risk within a relatively narrow zone. Farther north, the plume of backed moisture may lead to storms developing over eastern CO into western KS. This convection will eventually interact with the cold front by late evening. Depending on how uncapped the air mass is at that time, cells may congeal into a line of storms, which will be limited on the northern end by cooler air into NE, and on the southern end by possible capping. However, with very steep lapse rates aloft, a strong low-level jet and the frontal forcing, a few significant wind gusts cannot be ruled out along the NE/KS border overnight. ...Western TX... Strong heating will occur near the dryline, where an uncapped and very unstable air mass will develop. As dewpoints rise well into the 60s F, MLCAPE may exceed 4000 J/kg. Ample low-level convergence along the boundary will lead to scattered afternoon storms, some of which will be slow-moving supercells. Increasing and backing 850 mb winds with time may support a few east/southeast cell motions, with localized very large hail. In addition, hail-laden outflows may lead to wind damage. ..Jewell.. 04/30/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1249 AM CDT Tue Apr 30 2024 Valid 011200Z - 021200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER THE CENTRAL PLAINS...WITH SCATTERED SEVERE STORMS FROM WESTERN TEXAS INTO SOUTHERN NEBRASKA... ...SUMMARY... Scattered severe thunderstorms will be possible across parts of the central and southern Plains on Wednesday. A few tornadoes (including potential for a strong tornado), very large hail and damaging winds are expected. ...Synopsis... On Wednesday, an upper trough will extend from MT into the Great Basin by late afternoon, with increasing west/southwest flow aloft spreading into the central and northern Plains. Height falls with this trough will occur mainly overnight and into Thursday morning over the Plains, with 500 mb southwesterlies increasing all the while. Farther south, modest midlevel westerlies will exist from western TX into northern Mexico, the upper-level winds more prominent at over 60 kt at 300 mb. At the surface, low pressure will deepen over the central High Plains in advance of the upper trough, with a warm front lifting north across KS during the day. This front will reach into far southern NE during the late evening and overnight, with 60s F dewpoints possibly reaching I-80 into eastern NE by 12Z Thursday. Backed surface winds north of the warm front will also lead to rising dewpoints into western KS and far eastern CO toward the low, while robust moisture builds east of the dryline from southwest KS into western TX. Aiding both moisture advection and shear will be an increasing low-level jet which will exceed 50 kt Wednesday evening, affecting the majority of the central and southern Plains. Finally, a cold front will move into western NE and KS by around 06Z, and surge east toward the MO Valley into Thursday morning, augmented with thunderstorm outflow. ...Central Plains... Several possible severe-weather regimes may occur Wednesday into Wednesday night, with initial activity expected along the warm front during the day from south-central into eastern KS. This early activity will begin elevated, but instability may be strong and support occasional hail. With time, additional activity could develop along any outflow boundaries as theta-e advection persists, and a few surface-based cells may result by afternoon with hail or tornado risk. Later in the day and coincident with peak heating, widely spaced supercells are anticipated along the dryline from western KS into northwest TX. Given that this area will be well ahead of the upper trough, large-scale support will be minimal. However, strong heating and mid to upper 60s F dewpoints will still lead to at least isolated supercells capable of very large hail, and tornado risk within a relatively narrow zone. Farther north, the plume of backed moisture may lead to storms developing over eastern CO into western KS. This convection will eventually interact with the cold front by late evening. Depending on how uncapped the air mass is at that time, cells may congeal into a line of storms, which will be limited on the northern end by cooler air into NE, and on the southern end by possible capping. However, with very steep lapse rates aloft, a strong low-level jet and the frontal forcing, a few significant wind gusts cannot be ruled out along the NE/KS border overnight. ...Western TX... Strong heating will occur near the dryline, where an uncapped and very unstable air mass will develop. As dewpoints rise well into the 60s F, MLCAPE may exceed 4000 J/kg. Ample low-level convergence along the boundary will lead to scattered afternoon storms, some of which will be slow-moving supercells. Increasing and backing 850 mb winds with time may support a few east/southeast cell motions, with localized very large hail. In addition, hail-laden outflows may lead to wind damage. ..Jewell.. 04/30/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1257 AM CDT Tue Apr 30 2024 Valid 301200Z - 011200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MID MISSOURI VALLEY INTO THE CENTRAL PLAINS... ...SUMMARY... Severe thunderstorms will be possible this afternoon and evening from parts of the upper Mississippi Valley southwestward into the mid Missouri Valley, and central to southern Plains. The greatest threat is expected from western and central Iowa southwestward across far southeast Nebraska, far northwest Missouri into northeast Kansas, where very large hail, severe wind gusts (possibly above 70 mph) and a few tornadoes are expected. ...Upper Midwest/Mid Missouri Valley/Central Plains... An upper-level trough will move into the central and northern Plains today, as an associated 60 to 70 knot mid-level jet moves through the trough. At the surface, a deepening low will move into southeastern South Dakota, resulting in strong moisture advection across the mid Missouri Valley and central Plains. A north-northeast to south-southwest corridor of maximized low-level moisture will setup from eastern Kansas into western Iowa, where surface dewpoints will be in the lower to mid 60s F. Surface heating along this corridor will result in moderate instability by afternoon, with MLCAPE peaking in the 2000 to 3000 J/kg range. Ahead of the upper trough, large-scale ascent will likely support scattered thunderstorm development during the mid afternoon from eastern South Dakota into eastern Nebraska. This convection is expected to increase in intensity and coverage, moving eastward across Iowa, and developing south-southwestward into northeast Kansas during the late afternoon. A broken line of strong to severe storms will move east-southeastward toward the Mississippi River Valley in the early to mid evening. Along and near the instability axis, RAP forecast soundings at 21Z from near Omaha to Kansas City have supercell wind profiles, with strong speed shear in the low to midlevels and 0-6 km shear generally from 40 to 55 knots. Lapse rates are forecast to be very steep in the low to midlevels. 700-500 mb lapse rates around 8 C/km will be very favorable for supercells with large hail. The more dominant supercells should be capable of hailstones greater than 2 inches in diameter. 0-3 km lapse rates are forecast to be exceptionally steep, with some forecast soundings having 0-3 km lapse rates near 9 C/km. This should support a wind damage threat with supercells and the more intense short line segments. Wind gusts above 70 mph will be possible. Low-level shear should also be strong enough to support tornado development with the more intense supercells. The severe threat is expected to continue from late afternoon into the early to mid evening. The severe threat should become marginal by late evening, as the convective system moves through the lower Missouri Valley and southern sections of the central Plains. ...Southern Plains... West-southwesterly mid-level flow will be in place across the southern Plains today. At the surface, a corridor of maximized low-level moisture will be in place to the east of a dryline from western Oklahoma into west Texas. Surface dewpoints in the 60s F will contribute to the development of moderate instability by afternoon. MLCAPE is forecast to peak in the 2500 to 3500 J/kg range. Although large-scale ascent will likely be limited, low-level convergence near the dryline should result in isolated convective initiation during the mid to late afternoon. With any cell that can initiate and move away from the dryline, an isolated severe threat will be possible. RAP forecast soundings to the east of the dryline at 00Z/Wednesday generally have 0-6 km shear in the 30 to 40 knot range, with very steep lapse rates in the low to mid-levels. Some forecast soundings in western Oklahoma and northwest Texas have 0-3 km lapse rates near 9 C/km. This environment will likely be sufficient for organized cells with isolated large hail and strong gusts. The severe threat will be marginal from southwest Oklahoma into west Texas, where convective coverage is expected to be very isolated. ..Broyles/Thornton.. 04/30/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1257 AM CDT Tue Apr 30 2024 Valid 301200Z - 011200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MID MISSOURI VALLEY INTO THE CENTRAL PLAINS... ...SUMMARY... Severe thunderstorms will be possible this afternoon and evening from parts of the upper Mississippi Valley southwestward into the mid Missouri Valley, and central to southern Plains. The greatest threat is expected from western and central Iowa southwestward across far southeast Nebraska, far northwest Missouri into northeast Kansas, where very large hail, severe wind gusts (possibly above 70 mph) and a few tornadoes are expected. ...Upper Midwest/Mid Missouri Valley/Central Plains... An upper-level trough will move into the central and northern Plains today, as an associated 60 to 70 knot mid-level jet moves through the trough. At the surface, a deepening low will move into southeastern South Dakota, resulting in strong moisture advection across the mid Missouri Valley and central Plains. A north-northeast to south-southwest corridor of maximized low-level moisture will setup from eastern Kansas into western Iowa, where surface dewpoints will be in the lower to mid 60s F. Surface heating along this corridor will result in moderate instability by afternoon, with MLCAPE peaking in the 2000 to 3000 J/kg range. Ahead of the upper trough, large-scale ascent will likely support scattered thunderstorm development during the mid afternoon from eastern South Dakota into eastern Nebraska. This convection is expected to increase in intensity and coverage, moving eastward across Iowa, and developing south-southwestward into northeast Kansas during the late afternoon. A broken line of strong to severe storms will move east-southeastward toward the Mississippi River Valley in the early to mid evening. Along and near the instability axis, RAP forecast soundings at 21Z from near Omaha to Kansas City have supercell wind profiles, with strong speed shear in the low to midlevels and 0-6 km shear generally from 40 to 55 knots. Lapse rates are forecast to be very steep in the low to midlevels. 700-500 mb lapse rates around 8 C/km will be very favorable for supercells with large hail. The more dominant supercells should be capable of hailstones greater than 2 inches in diameter. 0-3 km lapse rates are forecast to be exceptionally steep, with some forecast soundings having 0-3 km lapse rates near 9 C/km. This should support a wind damage threat with supercells and the more intense short line segments. Wind gusts above 70 mph will be possible. Low-level shear should also be strong enough to support tornado development with the more intense supercells. The severe threat is expected to continue from late afternoon into the early to mid evening. The severe threat should become marginal by late evening, as the convective system moves through the lower Missouri Valley and southern sections of the central Plains. ...Southern Plains... West-southwesterly mid-level flow will be in place across the southern Plains today. At the surface, a corridor of maximized low-level moisture will be in place to the east of a dryline from western Oklahoma into west Texas. Surface dewpoints in the 60s F will contribute to the development of moderate instability by afternoon. MLCAPE is forecast to peak in the 2500 to 3500 J/kg range. Although large-scale ascent will likely be limited, low-level convergence near the dryline should result in isolated convective initiation during the mid to late afternoon. With any cell that can initiate and move away from the dryline, an isolated severe threat will be possible. RAP forecast soundings to the east of the dryline at 00Z/Wednesday generally have 0-6 km shear in the 30 to 40 knot range, with very steep lapse rates in the low to mid-levels. Some forecast soundings in western Oklahoma and northwest Texas have 0-3 km lapse rates near 9 C/km. This environment will likely be sufficient for organized cells with isolated large hail and strong gusts. The severe threat will be marginal from southwest Oklahoma into west Texas, where convective coverage is expected to be very isolated. ..Broyles/Thornton.. 04/30/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1257 AM CDT Tue Apr 30 2024 Valid 301200Z - 011200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MID MISSOURI VALLEY INTO THE CENTRAL PLAINS... ...SUMMARY... Severe thunderstorms will be possible this afternoon and evening from parts of the upper Mississippi Valley southwestward into the mid Missouri Valley, and central to southern Plains. The greatest threat is expected from western and central Iowa southwestward across far southeast Nebraska, far northwest Missouri into northeast Kansas, where very large hail, severe wind gusts (possibly above 70 mph) and a few tornadoes are expected. ...Upper Midwest/Mid Missouri Valley/Central Plains... An upper-level trough will move into the central and northern Plains today, as an associated 60 to 70 knot mid-level jet moves through the trough. At the surface, a deepening low will move into southeastern South Dakota, resulting in strong moisture advection across the mid Missouri Valley and central Plains. A north-northeast to south-southwest corridor of maximized low-level moisture will setup from eastern Kansas into western Iowa, where surface dewpoints will be in the lower to mid 60s F. Surface heating along this corridor will result in moderate instability by afternoon, with MLCAPE peaking in the 2000 to 3000 J/kg range. Ahead of the upper trough, large-scale ascent will likely support scattered thunderstorm development during the mid afternoon from eastern South Dakota into eastern Nebraska. This convection is expected to increase in intensity and coverage, moving eastward across Iowa, and developing south-southwestward into northeast Kansas during the late afternoon. A broken line of strong to severe storms will move east-southeastward toward the Mississippi River Valley in the early to mid evening. Along and near the instability axis, RAP forecast soundings at 21Z from near Omaha to Kansas City have supercell wind profiles, with strong speed shear in the low to midlevels and 0-6 km shear generally from 40 to 55 knots. Lapse rates are forecast to be very steep in the low to midlevels. 700-500 mb lapse rates around 8 C/km will be very favorable for supercells with large hail. The more dominant supercells should be capable of hailstones greater than 2 inches in diameter. 0-3 km lapse rates are forecast to be exceptionally steep, with some forecast soundings having 0-3 km lapse rates near 9 C/km. This should support a wind damage threat with supercells and the more intense short line segments. Wind gusts above 70 mph will be possible. Low-level shear should also be strong enough to support tornado development with the more intense supercells. The severe threat is expected to continue from late afternoon into the early to mid evening. The severe threat should become marginal by late evening, as the convective system moves through the lower Missouri Valley and southern sections of the central Plains. ...Southern Plains... West-southwesterly mid-level flow will be in place across the southern Plains today. At the surface, a corridor of maximized low-level moisture will be in place to the east of a dryline from western Oklahoma into west Texas. Surface dewpoints in the 60s F will contribute to the development of moderate instability by afternoon. MLCAPE is forecast to peak in the 2500 to 3500 J/kg range. Although large-scale ascent will likely be limited, low-level convergence near the dryline should result in isolated convective initiation during the mid to late afternoon. With any cell that can initiate and move away from the dryline, an isolated severe threat will be possible. RAP forecast soundings to the east of the dryline at 00Z/Wednesday generally have 0-6 km shear in the 30 to 40 knot range, with very steep lapse rates in the low to mid-levels. Some forecast soundings in western Oklahoma and northwest Texas have 0-3 km lapse rates near 9 C/km. This environment will likely be sufficient for organized cells with isolated large hail and strong gusts. The severe threat will be marginal from southwest Oklahoma into west Texas, where convective coverage is expected to be very isolated. ..Broyles/Thornton.. 04/30/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1257 AM CDT Tue Apr 30 2024 Valid 301200Z - 011200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MID MISSOURI VALLEY INTO THE CENTRAL PLAINS... ...SUMMARY... Severe thunderstorms will be possible this afternoon and evening from parts of the upper Mississippi Valley southwestward into the mid Missouri Valley, and central to southern Plains. The greatest threat is expected from western and central Iowa southwestward across far southeast Nebraska, far northwest Missouri into northeast Kansas, where very large hail, severe wind gusts (possibly above 70 mph) and a few tornadoes are expected. ...Upper Midwest/Mid Missouri Valley/Central Plains... An upper-level trough will move into the central and northern Plains today, as an associated 60 to 70 knot mid-level jet moves through the trough. At the surface, a deepening low will move into southeastern South Dakota, resulting in strong moisture advection across the mid Missouri Valley and central Plains. A north-northeast to south-southwest corridor of maximized low-level moisture will setup from eastern Kansas into western Iowa, where surface dewpoints will be in the lower to mid 60s F. Surface heating along this corridor will result in moderate instability by afternoon, with MLCAPE peaking in the 2000 to 3000 J/kg range. Ahead of the upper trough, large-scale ascent will likely support scattered thunderstorm development during the mid afternoon from eastern South Dakota into eastern Nebraska. This convection is expected to increase in intensity and coverage, moving eastward across Iowa, and developing south-southwestward into northeast Kansas during the late afternoon. A broken line of strong to severe storms will move east-southeastward toward the Mississippi River Valley in the early to mid evening. Along and near the instability axis, RAP forecast soundings at 21Z from near Omaha to Kansas City have supercell wind profiles, with strong speed shear in the low to midlevels and 0-6 km shear generally from 40 to 55 knots. Lapse rates are forecast to be very steep in the low to midlevels. 700-500 mb lapse rates around 8 C/km will be very favorable for supercells with large hail. The more dominant supercells should be capable of hailstones greater than 2 inches in diameter. 0-3 km lapse rates are forecast to be exceptionally steep, with some forecast soundings having 0-3 km lapse rates near 9 C/km. This should support a wind damage threat with supercells and the more intense short line segments. Wind gusts above 70 mph will be possible. Low-level shear should also be strong enough to support tornado development with the more intense supercells. The severe threat is expected to continue from late afternoon into the early to mid evening. The severe threat should become marginal by late evening, as the convective system moves through the lower Missouri Valley and southern sections of the central Plains. ...Southern Plains... West-southwesterly mid-level flow will be in place across the southern Plains today. At the surface, a corridor of maximized low-level moisture will be in place to the east of a dryline from western Oklahoma into west Texas. Surface dewpoints in the 60s F will contribute to the development of moderate instability by afternoon. MLCAPE is forecast to peak in the 2500 to 3500 J/kg range. Although large-scale ascent will likely be limited, low-level convergence near the dryline should result in isolated convective initiation during the mid to late afternoon. With any cell that can initiate and move away from the dryline, an isolated severe threat will be possible. RAP forecast soundings to the east of the dryline at 00Z/Wednesday generally have 0-6 km shear in the 30 to 40 knot range, with very steep lapse rates in the low to mid-levels. Some forecast soundings in western Oklahoma and northwest Texas have 0-3 km lapse rates near 9 C/km. This environment will likely be sufficient for organized cells with isolated large hail and strong gusts. The severe threat will be marginal from southwest Oklahoma into west Texas, where convective coverage is expected to be very isolated. ..Broyles/Thornton.. 04/30/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1257 AM CDT Tue Apr 30 2024 Valid 301200Z - 011200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE MID MISSOURI VALLEY INTO THE CENTRAL PLAINS... ...SUMMARY... Severe thunderstorms will be possible this afternoon and evening from parts of the upper Mississippi Valley southwestward into the mid Missouri Valley, and central to southern Plains. The greatest threat is expected from western and central Iowa southwestward across far southeast Nebraska, far northwest Missouri into northeast Kansas, where very large hail, severe wind gusts (possibly above 70 mph) and a few tornadoes are expected. ...Upper Midwest/Mid Missouri Valley/Central Plains... An upper-level trough will move into the central and northern Plains today, as an associated 60 to 70 knot mid-level jet moves through the trough. At the surface, a deepening low will move into southeastern South Dakota, resulting in strong moisture advection across the mid Missouri Valley and central Plains. A north-northeast to south-southwest corridor of maximized low-level moisture will setup from eastern Kansas into western Iowa, where surface dewpoints will be in the lower to mid 60s F. Surface heating along this corridor will result in moderate instability by afternoon, with MLCAPE peaking in the 2000 to 3000 J/kg range. Ahead of the upper trough, large-scale ascent will likely support scattered thunderstorm development during the mid afternoon from eastern South Dakota into eastern Nebraska. This convection is expected to increase in intensity and coverage, moving eastward across Iowa, and developing south-southwestward into northeast Kansas during the late afternoon. A broken line of strong to severe storms will move east-southeastward toward the Mississippi River Valley in the early to mid evening. Along and near the instability axis, RAP forecast soundings at 21Z from near Omaha to Kansas City have supercell wind profiles, with strong speed shear in the low to midlevels and 0-6 km shear generally from 40 to 55 knots. Lapse rates are forecast to be very steep in the low to midlevels. 700-500 mb lapse rates around 8 C/km will be very favorable for supercells with large hail. The more dominant supercells should be capable of hailstones greater than 2 inches in diameter. 0-3 km lapse rates are forecast to be exceptionally steep, with some forecast soundings having 0-3 km lapse rates near 9 C/km. This should support a wind damage threat with supercells and the more intense short line segments. Wind gusts above 70 mph will be possible. Low-level shear should also be strong enough to support tornado development with the more intense supercells. The severe threat is expected to continue from late afternoon into the early to mid evening. The severe threat should become marginal by late evening, as the convective system moves through the lower Missouri Valley and southern sections of the central Plains. ...Southern Plains... West-southwesterly mid-level flow will be in place across the southern Plains today. At the surface, a corridor of maximized low-level moisture will be in place to the east of a dryline from western Oklahoma into west Texas. Surface dewpoints in the 60s F will contribute to the development of moderate instability by afternoon. MLCAPE is forecast to peak in the 2500 to 3500 J/kg range. Although large-scale ascent will likely be limited, low-level convergence near the dryline should result in isolated convective initiation during the mid to late afternoon. With any cell that can initiate and move away from the dryline, an isolated severe threat will be possible. RAP forecast soundings to the east of the dryline at 00Z/Wednesday generally have 0-6 km shear in the 30 to 40 knot range, with very steep lapse rates in the low to mid-levels. Some forecast soundings in western Oklahoma and northwest Texas have 0-3 km lapse rates near 9 C/km. This environment will likely be sufficient for organized cells with isolated large hail and strong gusts. The severe threat will be marginal from southwest Oklahoma into west Texas, where convective coverage is expected to be very isolated. ..Broyles/Thornton.. 04/30/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0751 PM CDT Mon Apr 29 2024 Valid 300100Z - 301200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... No severe threat is expected this evening into tonight across the continental U.S. ...DISCUSSION... An upper-level trough will move across the Mississippi Valley this evening. At the surface, a moist airmass will be in place from the southern Plains and Southeast northward into the lower Great Lakes. Isolated to scattered thunderstorm development will be possible this evening into tonight across this moist airmass from the central Gulf Coast northward into the Ohio Valley and central Appalachians. Further west, isolated strong thunderstorms, associated with gusty winds and small hail, will be possible for another hour or so across south-central Texas. Thunderstorms may also develop across parts of the central and northern Rockies eastward into the northern High Plains. No appreciable severe threat is expected across the continental U.S. this evening and tonight. ..Broyles.. 04/30/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0751 PM CDT Mon Apr 29 2024 Valid 300100Z - 301200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... No severe threat is expected this evening into tonight across the continental U.S. ...DISCUSSION... An upper-level trough will move across the Mississippi Valley this evening. At the surface, a moist airmass will be in place from the southern Plains and Southeast northward into the lower Great Lakes. Isolated to scattered thunderstorm development will be possible this evening into tonight across this moist airmass from the central Gulf Coast northward into the Ohio Valley and central Appalachians. Further west, isolated strong thunderstorms, associated with gusty winds and small hail, will be possible for another hour or so across south-central Texas. Thunderstorms may also develop across parts of the central and northern Rockies eastward into the northern High Plains. No appreciable severe threat is expected across the continental U.S. this evening and tonight. ..Broyles.. 04/30/2024 Read more

No watches are valid as of Mon Apr 29 22:35:01 UTC 2024.