Aggregator

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0321 PM CDT Sun Apr 14 2024 Valid 161200Z - 221200Z A potent shortwave trough in the central Plains will be in the process of lifting northeastward and weakening on Tuesday/Wednesday. Another broad trough will move through the northern Plains into the Great Lakes and Northeast through the remainder of the week. Flow aloft within the southern half of the CONUS will generally become more zonal with time. Models suggest a more amplified pattern may develop by next weekend. At the surface, the initial trough/surface cyclone will push a relatively weak cold front through parts of the southern Plains late Tuesday into Wednesday. A secondary push of cooler air is possible late next week with some suggestion that the front will reach the Gulf during the weekend. ...Southern High Plains... Fire weather concerns will continue into Tuesday on the back side of the initial trough/surface cyclone. Winds will tend to weaken during the day as the cyclone moves farther north and east. A few hours of elevated to locally critical fire weather is possible. Some fire weather concerns are also possible on Wednesday as a weak lee cyclone develops within the zonal flow regime across the Divide. The most likely area for low-end concerns would be northeastern New Mexico. Given the weaker synoptic features, potential for critical fire weather is too low for highlights. ..Wendt.. 04/14/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0321 PM CDT Sun Apr 14 2024 Valid 161200Z - 221200Z A potent shortwave trough in the central Plains will be in the process of lifting northeastward and weakening on Tuesday/Wednesday. Another broad trough will move through the northern Plains into the Great Lakes and Northeast through the remainder of the week. Flow aloft within the southern half of the CONUS will generally become more zonal with time. Models suggest a more amplified pattern may develop by next weekend. At the surface, the initial trough/surface cyclone will push a relatively weak cold front through parts of the southern Plains late Tuesday into Wednesday. A secondary push of cooler air is possible late next week with some suggestion that the front will reach the Gulf during the weekend. ...Southern High Plains... Fire weather concerns will continue into Tuesday on the back side of the initial trough/surface cyclone. Winds will tend to weaken during the day as the cyclone moves farther north and east. A few hours of elevated to locally critical fire weather is possible. Some fire weather concerns are also possible on Wednesday as a weak lee cyclone develops within the zonal flow regime across the Divide. The most likely area for low-end concerns would be northeastern New Mexico. Given the weaker synoptic features, potential for critical fire weather is too low for highlights. ..Wendt.. 04/14/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0321 PM CDT Sun Apr 14 2024 Valid 161200Z - 221200Z A potent shortwave trough in the central Plains will be in the process of lifting northeastward and weakening on Tuesday/Wednesday. Another broad trough will move through the northern Plains into the Great Lakes and Northeast through the remainder of the week. Flow aloft within the southern half of the CONUS will generally become more zonal with time. Models suggest a more amplified pattern may develop by next weekend. At the surface, the initial trough/surface cyclone will push a relatively weak cold front through parts of the southern Plains late Tuesday into Wednesday. A secondary push of cooler air is possible late next week with some suggestion that the front will reach the Gulf during the weekend. ...Southern High Plains... Fire weather concerns will continue into Tuesday on the back side of the initial trough/surface cyclone. Winds will tend to weaken during the day as the cyclone moves farther north and east. A few hours of elevated to locally critical fire weather is possible. Some fire weather concerns are also possible on Wednesday as a weak lee cyclone develops within the zonal flow regime across the Divide. The most likely area for low-end concerns would be northeastern New Mexico. Given the weaker synoptic features, potential for critical fire weather is too low for highlights. ..Wendt.. 04/14/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0321 PM CDT Sun Apr 14 2024 Valid 161200Z - 221200Z A potent shortwave trough in the central Plains will be in the process of lifting northeastward and weakening on Tuesday/Wednesday. Another broad trough will move through the northern Plains into the Great Lakes and Northeast through the remainder of the week. Flow aloft within the southern half of the CONUS will generally become more zonal with time. Models suggest a more amplified pattern may develop by next weekend. At the surface, the initial trough/surface cyclone will push a relatively weak cold front through parts of the southern Plains late Tuesday into Wednesday. A secondary push of cooler air is possible late next week with some suggestion that the front will reach the Gulf during the weekend. ...Southern High Plains... Fire weather concerns will continue into Tuesday on the back side of the initial trough/surface cyclone. Winds will tend to weaken during the day as the cyclone moves farther north and east. A few hours of elevated to locally critical fire weather is possible. Some fire weather concerns are also possible on Wednesday as a weak lee cyclone develops within the zonal flow regime across the Divide. The most likely area for low-end concerns would be northeastern New Mexico. Given the weaker synoptic features, potential for critical fire weather is too low for highlights. ..Wendt.. 04/14/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0321 PM CDT Sun Apr 14 2024 Valid 161200Z - 221200Z A potent shortwave trough in the central Plains will be in the process of lifting northeastward and weakening on Tuesday/Wednesday. Another broad trough will move through the northern Plains into the Great Lakes and Northeast through the remainder of the week. Flow aloft within the southern half of the CONUS will generally become more zonal with time. Models suggest a more amplified pattern may develop by next weekend. At the surface, the initial trough/surface cyclone will push a relatively weak cold front through parts of the southern Plains late Tuesday into Wednesday. A secondary push of cooler air is possible late next week with some suggestion that the front will reach the Gulf during the weekend. ...Southern High Plains... Fire weather concerns will continue into Tuesday on the back side of the initial trough/surface cyclone. Winds will tend to weaken during the day as the cyclone moves farther north and east. A few hours of elevated to locally critical fire weather is possible. Some fire weather concerns are also possible on Wednesday as a weak lee cyclone develops within the zonal flow regime across the Divide. The most likely area for low-end concerns would be northeastern New Mexico. Given the weaker synoptic features, potential for critical fire weather is too low for highlights. ..Wendt.. 04/14/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0321 PM CDT Sun Apr 14 2024 Valid 161200Z - 221200Z A potent shortwave trough in the central Plains will be in the process of lifting northeastward and weakening on Tuesday/Wednesday. Another broad trough will move through the northern Plains into the Great Lakes and Northeast through the remainder of the week. Flow aloft within the southern half of the CONUS will generally become more zonal with time. Models suggest a more amplified pattern may develop by next weekend. At the surface, the initial trough/surface cyclone will push a relatively weak cold front through parts of the southern Plains late Tuesday into Wednesday. A secondary push of cooler air is possible late next week with some suggestion that the front will reach the Gulf during the weekend. ...Southern High Plains... Fire weather concerns will continue into Tuesday on the back side of the initial trough/surface cyclone. Winds will tend to weaken during the day as the cyclone moves farther north and east. A few hours of elevated to locally critical fire weather is possible. Some fire weather concerns are also possible on Wednesday as a weak lee cyclone develops within the zonal flow regime across the Divide. The most likely area for low-end concerns would be northeastern New Mexico. Given the weaker synoptic features, potential for critical fire weather is too low for highlights. ..Wendt.. 04/14/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0321 PM CDT Sun Apr 14 2024 Valid 161200Z - 221200Z A potent shortwave trough in the central Plains will be in the process of lifting northeastward and weakening on Tuesday/Wednesday. Another broad trough will move through the northern Plains into the Great Lakes and Northeast through the remainder of the week. Flow aloft within the southern half of the CONUS will generally become more zonal with time. Models suggest a more amplified pattern may develop by next weekend. At the surface, the initial trough/surface cyclone will push a relatively weak cold front through parts of the southern Plains late Tuesday into Wednesday. A secondary push of cooler air is possible late next week with some suggestion that the front will reach the Gulf during the weekend. ...Southern High Plains... Fire weather concerns will continue into Tuesday on the back side of the initial trough/surface cyclone. Winds will tend to weaken during the day as the cyclone moves farther north and east. A few hours of elevated to locally critical fire weather is possible. Some fire weather concerns are also possible on Wednesday as a weak lee cyclone develops within the zonal flow regime across the Divide. The most likely area for low-end concerns would be northeastern New Mexico. Given the weaker synoptic features, potential for critical fire weather is too low for highlights. ..Wendt.. 04/14/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No watches are valid as of Sun Apr 14 20:27:02 UTC 2024.

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Sun Apr 14 2024 Valid 142000Z - 151200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM EASTERN OHIO EAST-NORTHEASTWARD ACROSS PENNSYLVANIA... ...SUMMARY... Severe thunderstorms are expected to develop late this afternoon in a narrow corridor across the upper Ohio Valley into Pennsylvania and vicinity. Damaging winds should be the main threat. Severe hail and perhaps a couple of tornadoes also appear possible as this activity spreads southeastward into this evening. ...Discussion... Aside from minor line tweaks in the northern Ohio area, the severe-weather risk areas remain unchanged, with prior forecast reasoning -- highlighting development of strong to severe storms this afternoon -- still valid. For additional short-term forecast information in this region, please refer to SWOMCD #435. Elsewhere, the portion of the thunder area across Nevada is being removed in this update. ..Goss.. 04/14/2024 .PREV DISCUSSION... /ISSUED 1129 AM CDT Sun Apr 14 2024/ ...Ohio Valley into the Mid-Atlantic and Northeast... Surface analysis late this morning shows the northeastern rim of 50s dewpoints over northern KY/southwest OH being quickly advected east-northeastward on a 40-kt west-southwesterly LLJ. The Upper OH Valley is located immediately downstream of a mid-level vorticity maximum over Lake Michigan. This disturbance will continue to move into the base of the larger-scale eastern Canada/Northeast U.S. mid-level trough. An accompanying weak low will migrate eastward from the Great Lakes across NY, while a weak cold front extends to the west-southwest and is forecast to push east-southeast across the Lower Great Lakes before weakening and becoming draped across the Upper OH Valley late. Continued low-level moist advection will likely result in upper 40s to low 50s surface dewpoints within a narrow corridor along and south of a cold front from OH into PA and southern NY. Steep 700-500 mb lapse rates due in part to cool mid levels (i.e., -18 deg C at 500 mb) and heating will yield 500-1250 J/kg MLCAPE by mid-late afternoon. Surface-based thunderstorm initiation across this region will likely be delayed until 20-21Z or later, as lingering MLCIN and a cap gradually erodes. Initial development should be focused along the front across parts of eastern OH into western/central PA, with additional development eventually occurring into eastern PA and parts of southern NY. Given strong deep-layer shear and favorable lapse rates, large hail may occur with the more robust cores initially. Some threat for a couple of tornadoes may also exist with quasi-discrete supercells early in the thunderstorm life cycle, as sufficient low-level shear will be present for updraft rotation. But, with the surface front aligned mostly parallel to the enhanced westerly low/mid-level flow, upscale growth into small bowing clusters will likely occur as additional storms develop and cold pools merge as the band of storms moves southeastward. Scattered damaging winds will then likely become the main threat with these clusters through the early evening. As instability wanes after sunset, the wind threat will gradually decrease with southward/eastward extent. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Sun Apr 14 2024 Valid 142000Z - 151200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM EASTERN OHIO EAST-NORTHEASTWARD ACROSS PENNSYLVANIA... ...SUMMARY... Severe thunderstorms are expected to develop late this afternoon in a narrow corridor across the upper Ohio Valley into Pennsylvania and vicinity. Damaging winds should be the main threat. Severe hail and perhaps a couple of tornadoes also appear possible as this activity spreads southeastward into this evening. ...Discussion... Aside from minor line tweaks in the northern Ohio area, the severe-weather risk areas remain unchanged, with prior forecast reasoning -- highlighting development of strong to severe storms this afternoon -- still valid. For additional short-term forecast information in this region, please refer to SWOMCD #435. Elsewhere, the portion of the thunder area across Nevada is being removed in this update. ..Goss.. 04/14/2024 .PREV DISCUSSION... /ISSUED 1129 AM CDT Sun Apr 14 2024/ ...Ohio Valley into the Mid-Atlantic and Northeast... Surface analysis late this morning shows the northeastern rim of 50s dewpoints over northern KY/southwest OH being quickly advected east-northeastward on a 40-kt west-southwesterly LLJ. The Upper OH Valley is located immediately downstream of a mid-level vorticity maximum over Lake Michigan. This disturbance will continue to move into the base of the larger-scale eastern Canada/Northeast U.S. mid-level trough. An accompanying weak low will migrate eastward from the Great Lakes across NY, while a weak cold front extends to the west-southwest and is forecast to push east-southeast across the Lower Great Lakes before weakening and becoming draped across the Upper OH Valley late. Continued low-level moist advection will likely result in upper 40s to low 50s surface dewpoints within a narrow corridor along and south of a cold front from OH into PA and southern NY. Steep 700-500 mb lapse rates due in part to cool mid levels (i.e., -18 deg C at 500 mb) and heating will yield 500-1250 J/kg MLCAPE by mid-late afternoon. Surface-based thunderstorm initiation across this region will likely be delayed until 20-21Z or later, as lingering MLCIN and a cap gradually erodes. Initial development should be focused along the front across parts of eastern OH into western/central PA, with additional development eventually occurring into eastern PA and parts of southern NY. Given strong deep-layer shear and favorable lapse rates, large hail may occur with the more robust cores initially. Some threat for a couple of tornadoes may also exist with quasi-discrete supercells early in the thunderstorm life cycle, as sufficient low-level shear will be present for updraft rotation. But, with the surface front aligned mostly parallel to the enhanced westerly low/mid-level flow, upscale growth into small bowing clusters will likely occur as additional storms develop and cold pools merge as the band of storms moves southeastward. Scattered damaging winds will then likely become the main threat with these clusters through the early evening. As instability wanes after sunset, the wind threat will gradually decrease with southward/eastward extent. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Sun Apr 14 2024 Valid 142000Z - 151200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM EASTERN OHIO EAST-NORTHEASTWARD ACROSS PENNSYLVANIA... ...SUMMARY... Severe thunderstorms are expected to develop late this afternoon in a narrow corridor across the upper Ohio Valley into Pennsylvania and vicinity. Damaging winds should be the main threat. Severe hail and perhaps a couple of tornadoes also appear possible as this activity spreads southeastward into this evening. ...Discussion... Aside from minor line tweaks in the northern Ohio area, the severe-weather risk areas remain unchanged, with prior forecast reasoning -- highlighting development of strong to severe storms this afternoon -- still valid. For additional short-term forecast information in this region, please refer to SWOMCD #435. Elsewhere, the portion of the thunder area across Nevada is being removed in this update. ..Goss.. 04/14/2024 .PREV DISCUSSION... /ISSUED 1129 AM CDT Sun Apr 14 2024/ ...Ohio Valley into the Mid-Atlantic and Northeast... Surface analysis late this morning shows the northeastern rim of 50s dewpoints over northern KY/southwest OH being quickly advected east-northeastward on a 40-kt west-southwesterly LLJ. The Upper OH Valley is located immediately downstream of a mid-level vorticity maximum over Lake Michigan. This disturbance will continue to move into the base of the larger-scale eastern Canada/Northeast U.S. mid-level trough. An accompanying weak low will migrate eastward from the Great Lakes across NY, while a weak cold front extends to the west-southwest and is forecast to push east-southeast across the Lower Great Lakes before weakening and becoming draped across the Upper OH Valley late. Continued low-level moist advection will likely result in upper 40s to low 50s surface dewpoints within a narrow corridor along and south of a cold front from OH into PA and southern NY. Steep 700-500 mb lapse rates due in part to cool mid levels (i.e., -18 deg C at 500 mb) and heating will yield 500-1250 J/kg MLCAPE by mid-late afternoon. Surface-based thunderstorm initiation across this region will likely be delayed until 20-21Z or later, as lingering MLCIN and a cap gradually erodes. Initial development should be focused along the front across parts of eastern OH into western/central PA, with additional development eventually occurring into eastern PA and parts of southern NY. Given strong deep-layer shear and favorable lapse rates, large hail may occur with the more robust cores initially. Some threat for a couple of tornadoes may also exist with quasi-discrete supercells early in the thunderstorm life cycle, as sufficient low-level shear will be present for updraft rotation. But, with the surface front aligned mostly parallel to the enhanced westerly low/mid-level flow, upscale growth into small bowing clusters will likely occur as additional storms develop and cold pools merge as the band of storms moves southeastward. Scattered damaging winds will then likely become the main threat with these clusters through the early evening. As instability wanes after sunset, the wind threat will gradually decrease with southward/eastward extent. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Sun Apr 14 2024 Valid 142000Z - 151200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM EASTERN OHIO EAST-NORTHEASTWARD ACROSS PENNSYLVANIA... ...SUMMARY... Severe thunderstorms are expected to develop late this afternoon in a narrow corridor across the upper Ohio Valley into Pennsylvania and vicinity. Damaging winds should be the main threat. Severe hail and perhaps a couple of tornadoes also appear possible as this activity spreads southeastward into this evening. ...Discussion... Aside from minor line tweaks in the northern Ohio area, the severe-weather risk areas remain unchanged, with prior forecast reasoning -- highlighting development of strong to severe storms this afternoon -- still valid. For additional short-term forecast information in this region, please refer to SWOMCD #435. Elsewhere, the portion of the thunder area across Nevada is being removed in this update. ..Goss.. 04/14/2024 .PREV DISCUSSION... /ISSUED 1129 AM CDT Sun Apr 14 2024/ ...Ohio Valley into the Mid-Atlantic and Northeast... Surface analysis late this morning shows the northeastern rim of 50s dewpoints over northern KY/southwest OH being quickly advected east-northeastward on a 40-kt west-southwesterly LLJ. The Upper OH Valley is located immediately downstream of a mid-level vorticity maximum over Lake Michigan. This disturbance will continue to move into the base of the larger-scale eastern Canada/Northeast U.S. mid-level trough. An accompanying weak low will migrate eastward from the Great Lakes across NY, while a weak cold front extends to the west-southwest and is forecast to push east-southeast across the Lower Great Lakes before weakening and becoming draped across the Upper OH Valley late. Continued low-level moist advection will likely result in upper 40s to low 50s surface dewpoints within a narrow corridor along and south of a cold front from OH into PA and southern NY. Steep 700-500 mb lapse rates due in part to cool mid levels (i.e., -18 deg C at 500 mb) and heating will yield 500-1250 J/kg MLCAPE by mid-late afternoon. Surface-based thunderstorm initiation across this region will likely be delayed until 20-21Z or later, as lingering MLCIN and a cap gradually erodes. Initial development should be focused along the front across parts of eastern OH into western/central PA, with additional development eventually occurring into eastern PA and parts of southern NY. Given strong deep-layer shear and favorable lapse rates, large hail may occur with the more robust cores initially. Some threat for a couple of tornadoes may also exist with quasi-discrete supercells early in the thunderstorm life cycle, as sufficient low-level shear will be present for updraft rotation. But, with the surface front aligned mostly parallel to the enhanced westerly low/mid-level flow, upscale growth into small bowing clusters will likely occur as additional storms develop and cold pools merge as the band of storms moves southeastward. Scattered damaging winds will then likely become the main threat with these clusters through the early evening. As instability wanes after sunset, the wind threat will gradually decrease with southward/eastward extent. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Sun Apr 14 2024 Valid 142000Z - 151200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM EASTERN OHIO EAST-NORTHEASTWARD ACROSS PENNSYLVANIA... ...SUMMARY... Severe thunderstorms are expected to develop late this afternoon in a narrow corridor across the upper Ohio Valley into Pennsylvania and vicinity. Damaging winds should be the main threat. Severe hail and perhaps a couple of tornadoes also appear possible as this activity spreads southeastward into this evening. ...Discussion... Aside from minor line tweaks in the northern Ohio area, the severe-weather risk areas remain unchanged, with prior forecast reasoning -- highlighting development of strong to severe storms this afternoon -- still valid. For additional short-term forecast information in this region, please refer to SWOMCD #435. Elsewhere, the portion of the thunder area across Nevada is being removed in this update. ..Goss.. 04/14/2024 .PREV DISCUSSION... /ISSUED 1129 AM CDT Sun Apr 14 2024/ ...Ohio Valley into the Mid-Atlantic and Northeast... Surface analysis late this morning shows the northeastern rim of 50s dewpoints over northern KY/southwest OH being quickly advected east-northeastward on a 40-kt west-southwesterly LLJ. The Upper OH Valley is located immediately downstream of a mid-level vorticity maximum over Lake Michigan. This disturbance will continue to move into the base of the larger-scale eastern Canada/Northeast U.S. mid-level trough. An accompanying weak low will migrate eastward from the Great Lakes across NY, while a weak cold front extends to the west-southwest and is forecast to push east-southeast across the Lower Great Lakes before weakening and becoming draped across the Upper OH Valley late. Continued low-level moist advection will likely result in upper 40s to low 50s surface dewpoints within a narrow corridor along and south of a cold front from OH into PA and southern NY. Steep 700-500 mb lapse rates due in part to cool mid levels (i.e., -18 deg C at 500 mb) and heating will yield 500-1250 J/kg MLCAPE by mid-late afternoon. Surface-based thunderstorm initiation across this region will likely be delayed until 20-21Z or later, as lingering MLCIN and a cap gradually erodes. Initial development should be focused along the front across parts of eastern OH into western/central PA, with additional development eventually occurring into eastern PA and parts of southern NY. Given strong deep-layer shear and favorable lapse rates, large hail may occur with the more robust cores initially. Some threat for a couple of tornadoes may also exist with quasi-discrete supercells early in the thunderstorm life cycle, as sufficient low-level shear will be present for updraft rotation. But, with the surface front aligned mostly parallel to the enhanced westerly low/mid-level flow, upscale growth into small bowing clusters will likely occur as additional storms develop and cold pools merge as the band of storms moves southeastward. Scattered damaging winds will then likely become the main threat with these clusters through the early evening. As instability wanes after sunset, the wind threat will gradually decrease with southward/eastward extent. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Sun Apr 14 2024 Valid 142000Z - 151200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM EASTERN OHIO EAST-NORTHEASTWARD ACROSS PENNSYLVANIA... ...SUMMARY... Severe thunderstorms are expected to develop late this afternoon in a narrow corridor across the upper Ohio Valley into Pennsylvania and vicinity. Damaging winds should be the main threat. Severe hail and perhaps a couple of tornadoes also appear possible as this activity spreads southeastward into this evening. ...Discussion... Aside from minor line tweaks in the northern Ohio area, the severe-weather risk areas remain unchanged, with prior forecast reasoning -- highlighting development of strong to severe storms this afternoon -- still valid. For additional short-term forecast information in this region, please refer to SWOMCD #435. Elsewhere, the portion of the thunder area across Nevada is being removed in this update. ..Goss.. 04/14/2024 .PREV DISCUSSION... /ISSUED 1129 AM CDT Sun Apr 14 2024/ ...Ohio Valley into the Mid-Atlantic and Northeast... Surface analysis late this morning shows the northeastern rim of 50s dewpoints over northern KY/southwest OH being quickly advected east-northeastward on a 40-kt west-southwesterly LLJ. The Upper OH Valley is located immediately downstream of a mid-level vorticity maximum over Lake Michigan. This disturbance will continue to move into the base of the larger-scale eastern Canada/Northeast U.S. mid-level trough. An accompanying weak low will migrate eastward from the Great Lakes across NY, while a weak cold front extends to the west-southwest and is forecast to push east-southeast across the Lower Great Lakes before weakening and becoming draped across the Upper OH Valley late. Continued low-level moist advection will likely result in upper 40s to low 50s surface dewpoints within a narrow corridor along and south of a cold front from OH into PA and southern NY. Steep 700-500 mb lapse rates due in part to cool mid levels (i.e., -18 deg C at 500 mb) and heating will yield 500-1250 J/kg MLCAPE by mid-late afternoon. Surface-based thunderstorm initiation across this region will likely be delayed until 20-21Z or later, as lingering MLCIN and a cap gradually erodes. Initial development should be focused along the front across parts of eastern OH into western/central PA, with additional development eventually occurring into eastern PA and parts of southern NY. Given strong deep-layer shear and favorable lapse rates, large hail may occur with the more robust cores initially. Some threat for a couple of tornadoes may also exist with quasi-discrete supercells early in the thunderstorm life cycle, as sufficient low-level shear will be present for updraft rotation. But, with the surface front aligned mostly parallel to the enhanced westerly low/mid-level flow, upscale growth into small bowing clusters will likely occur as additional storms develop and cold pools merge as the band of storms moves southeastward. Scattered damaging winds will then likely become the main threat with these clusters through the early evening. As instability wanes after sunset, the wind threat will gradually decrease with southward/eastward extent. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Sun Apr 14 2024 Valid 142000Z - 151200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM EASTERN OHIO EAST-NORTHEASTWARD ACROSS PENNSYLVANIA... ...SUMMARY... Severe thunderstorms are expected to develop late this afternoon in a narrow corridor across the upper Ohio Valley into Pennsylvania and vicinity. Damaging winds should be the main threat. Severe hail and perhaps a couple of tornadoes also appear possible as this activity spreads southeastward into this evening. ...Discussion... Aside from minor line tweaks in the northern Ohio area, the severe-weather risk areas remain unchanged, with prior forecast reasoning -- highlighting development of strong to severe storms this afternoon -- still valid. For additional short-term forecast information in this region, please refer to SWOMCD #435. Elsewhere, the portion of the thunder area across Nevada is being removed in this update. ..Goss.. 04/14/2024 .PREV DISCUSSION... /ISSUED 1129 AM CDT Sun Apr 14 2024/ ...Ohio Valley into the Mid-Atlantic and Northeast... Surface analysis late this morning shows the northeastern rim of 50s dewpoints over northern KY/southwest OH being quickly advected east-northeastward on a 40-kt west-southwesterly LLJ. The Upper OH Valley is located immediately downstream of a mid-level vorticity maximum over Lake Michigan. This disturbance will continue to move into the base of the larger-scale eastern Canada/Northeast U.S. mid-level trough. An accompanying weak low will migrate eastward from the Great Lakes across NY, while a weak cold front extends to the west-southwest and is forecast to push east-southeast across the Lower Great Lakes before weakening and becoming draped across the Upper OH Valley late. Continued low-level moist advection will likely result in upper 40s to low 50s surface dewpoints within a narrow corridor along and south of a cold front from OH into PA and southern NY. Steep 700-500 mb lapse rates due in part to cool mid levels (i.e., -18 deg C at 500 mb) and heating will yield 500-1250 J/kg MLCAPE by mid-late afternoon. Surface-based thunderstorm initiation across this region will likely be delayed until 20-21Z or later, as lingering MLCIN and a cap gradually erodes. Initial development should be focused along the front across parts of eastern OH into western/central PA, with additional development eventually occurring into eastern PA and parts of southern NY. Given strong deep-layer shear and favorable lapse rates, large hail may occur with the more robust cores initially. Some threat for a couple of tornadoes may also exist with quasi-discrete supercells early in the thunderstorm life cycle, as sufficient low-level shear will be present for updraft rotation. But, with the surface front aligned mostly parallel to the enhanced westerly low/mid-level flow, upscale growth into small bowing clusters will likely occur as additional storms develop and cold pools merge as the band of storms moves southeastward. Scattered damaging winds will then likely become the main threat with these clusters through the early evening. As instability wanes after sunset, the wind threat will gradually decrease with southward/eastward extent. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Sun Apr 14 2024 Valid 142000Z - 151200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM EASTERN OHIO EAST-NORTHEASTWARD ACROSS PENNSYLVANIA... ...SUMMARY... Severe thunderstorms are expected to develop late this afternoon in a narrow corridor across the upper Ohio Valley into Pennsylvania and vicinity. Damaging winds should be the main threat. Severe hail and perhaps a couple of tornadoes also appear possible as this activity spreads southeastward into this evening. ...Discussion... Aside from minor line tweaks in the northern Ohio area, the severe-weather risk areas remain unchanged, with prior forecast reasoning -- highlighting development of strong to severe storms this afternoon -- still valid. For additional short-term forecast information in this region, please refer to SWOMCD #435. Elsewhere, the portion of the thunder area across Nevada is being removed in this update. ..Goss.. 04/14/2024 .PREV DISCUSSION... /ISSUED 1129 AM CDT Sun Apr 14 2024/ ...Ohio Valley into the Mid-Atlantic and Northeast... Surface analysis late this morning shows the northeastern rim of 50s dewpoints over northern KY/southwest OH being quickly advected east-northeastward on a 40-kt west-southwesterly LLJ. The Upper OH Valley is located immediately downstream of a mid-level vorticity maximum over Lake Michigan. This disturbance will continue to move into the base of the larger-scale eastern Canada/Northeast U.S. mid-level trough. An accompanying weak low will migrate eastward from the Great Lakes across NY, while a weak cold front extends to the west-southwest and is forecast to push east-southeast across the Lower Great Lakes before weakening and becoming draped across the Upper OH Valley late. Continued low-level moist advection will likely result in upper 40s to low 50s surface dewpoints within a narrow corridor along and south of a cold front from OH into PA and southern NY. Steep 700-500 mb lapse rates due in part to cool mid levels (i.e., -18 deg C at 500 mb) and heating will yield 500-1250 J/kg MLCAPE by mid-late afternoon. Surface-based thunderstorm initiation across this region will likely be delayed until 20-21Z or later, as lingering MLCIN and a cap gradually erodes. Initial development should be focused along the front across parts of eastern OH into western/central PA, with additional development eventually occurring into eastern PA and parts of southern NY. Given strong deep-layer shear and favorable lapse rates, large hail may occur with the more robust cores initially. Some threat for a couple of tornadoes may also exist with quasi-discrete supercells early in the thunderstorm life cycle, as sufficient low-level shear will be present for updraft rotation. But, with the surface front aligned mostly parallel to the enhanced westerly low/mid-level flow, upscale growth into small bowing clusters will likely occur as additional storms develop and cold pools merge as the band of storms moves southeastward. Scattered damaging winds will then likely become the main threat with these clusters through the early evening. As instability wanes after sunset, the wind threat will gradually decrease with southward/eastward extent. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Sun Apr 14 2024 Valid 142000Z - 151200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM EASTERN OHIO EAST-NORTHEASTWARD ACROSS PENNSYLVANIA... ...SUMMARY... Severe thunderstorms are expected to develop late this afternoon in a narrow corridor across the upper Ohio Valley into Pennsylvania and vicinity. Damaging winds should be the main threat. Severe hail and perhaps a couple of tornadoes also appear possible as this activity spreads southeastward into this evening. ...Discussion... Aside from minor line tweaks in the northern Ohio area, the severe-weather risk areas remain unchanged, with prior forecast reasoning -- highlighting development of strong to severe storms this afternoon -- still valid. For additional short-term forecast information in this region, please refer to SWOMCD #435. Elsewhere, the portion of the thunder area across Nevada is being removed in this update. ..Goss.. 04/14/2024 .PREV DISCUSSION... /ISSUED 1129 AM CDT Sun Apr 14 2024/ ...Ohio Valley into the Mid-Atlantic and Northeast... Surface analysis late this morning shows the northeastern rim of 50s dewpoints over northern KY/southwest OH being quickly advected east-northeastward on a 40-kt west-southwesterly LLJ. The Upper OH Valley is located immediately downstream of a mid-level vorticity maximum over Lake Michigan. This disturbance will continue to move into the base of the larger-scale eastern Canada/Northeast U.S. mid-level trough. An accompanying weak low will migrate eastward from the Great Lakes across NY, while a weak cold front extends to the west-southwest and is forecast to push east-southeast across the Lower Great Lakes before weakening and becoming draped across the Upper OH Valley late. Continued low-level moist advection will likely result in upper 40s to low 50s surface dewpoints within a narrow corridor along and south of a cold front from OH into PA and southern NY. Steep 700-500 mb lapse rates due in part to cool mid levels (i.e., -18 deg C at 500 mb) and heating will yield 500-1250 J/kg MLCAPE by mid-late afternoon. Surface-based thunderstorm initiation across this region will likely be delayed until 20-21Z or later, as lingering MLCIN and a cap gradually erodes. Initial development should be focused along the front across parts of eastern OH into western/central PA, with additional development eventually occurring into eastern PA and parts of southern NY. Given strong deep-layer shear and favorable lapse rates, large hail may occur with the more robust cores initially. Some threat for a couple of tornadoes may also exist with quasi-discrete supercells early in the thunderstorm life cycle, as sufficient low-level shear will be present for updraft rotation. But, with the surface front aligned mostly parallel to the enhanced westerly low/mid-level flow, upscale growth into small bowing clusters will likely occur as additional storms develop and cold pools merge as the band of storms moves southeastward. Scattered damaging winds will then likely become the main threat with these clusters through the early evening. As instability wanes after sunset, the wind threat will gradually decrease with southward/eastward extent. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Sun Apr 14 2024 Valid 142000Z - 151200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM EASTERN OHIO EAST-NORTHEASTWARD ACROSS PENNSYLVANIA... ...SUMMARY... Severe thunderstorms are expected to develop late this afternoon in a narrow corridor across the upper Ohio Valley into Pennsylvania and vicinity. Damaging winds should be the main threat. Severe hail and perhaps a couple of tornadoes also appear possible as this activity spreads southeastward into this evening. ...Discussion... Aside from minor line tweaks in the northern Ohio area, the severe-weather risk areas remain unchanged, with prior forecast reasoning -- highlighting development of strong to severe storms this afternoon -- still valid. For additional short-term forecast information in this region, please refer to SWOMCD #435. Elsewhere, the portion of the thunder area across Nevada is being removed in this update. ..Goss.. 04/14/2024 .PREV DISCUSSION... /ISSUED 1129 AM CDT Sun Apr 14 2024/ ...Ohio Valley into the Mid-Atlantic and Northeast... Surface analysis late this morning shows the northeastern rim of 50s dewpoints over northern KY/southwest OH being quickly advected east-northeastward on a 40-kt west-southwesterly LLJ. The Upper OH Valley is located immediately downstream of a mid-level vorticity maximum over Lake Michigan. This disturbance will continue to move into the base of the larger-scale eastern Canada/Northeast U.S. mid-level trough. An accompanying weak low will migrate eastward from the Great Lakes across NY, while a weak cold front extends to the west-southwest and is forecast to push east-southeast across the Lower Great Lakes before weakening and becoming draped across the Upper OH Valley late. Continued low-level moist advection will likely result in upper 40s to low 50s surface dewpoints within a narrow corridor along and south of a cold front from OH into PA and southern NY. Steep 700-500 mb lapse rates due in part to cool mid levels (i.e., -18 deg C at 500 mb) and heating will yield 500-1250 J/kg MLCAPE by mid-late afternoon. Surface-based thunderstorm initiation across this region will likely be delayed until 20-21Z or later, as lingering MLCIN and a cap gradually erodes. Initial development should be focused along the front across parts of eastern OH into western/central PA, with additional development eventually occurring into eastern PA and parts of southern NY. Given strong deep-layer shear and favorable lapse rates, large hail may occur with the more robust cores initially. Some threat for a couple of tornadoes may also exist with quasi-discrete supercells early in the thunderstorm life cycle, as sufficient low-level shear will be present for updraft rotation. But, with the surface front aligned mostly parallel to the enhanced westerly low/mid-level flow, upscale growth into small bowing clusters will likely occur as additional storms develop and cold pools merge as the band of storms moves southeastward. Scattered damaging winds will then likely become the main threat with these clusters through the early evening. As instability wanes after sunset, the wind threat will gradually decrease with southward/eastward extent. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0204 PM CDT Sun Apr 14 2024 Valid 151200Z - 161200Z ...CRITICAL FIRE WEATHER AREA FOR CENTRAL AND SOUTHERN HIGH PLAINS... The critical area has been expanded based on the latest guidance. RH in the single digits appears likely for a broad portion of the regions. The potential for extremely critical fire weather remains across northeast New Mexico into southeast Colorado and parts of western Kansas. Duration of these conditions will be the primary uncertainty as the most favorable overlap of synoptic features may only be brief. There is some potential for elevated fire weather in parts of northwestern Iowa into southeast South Dakota. Dry air is in place in the upper Midwest and winds will increase ahead of a lifting warm front prior to precipitation arriving during the evening/overnight. With these dry/windy conditions occurring primarily over marginally dry fuels (drier fuels exist to the southwest), the threat may remain localized. ..Wendt.. 04/14/2024 .PREV DISCUSSION... /ISSUED 0207 AM CDT Sun Apr 14 2024/ ...Synopsis... An upper low and strong jet streak are forecast to intensify and eject eastward over the southern and central Rockies D2/Monday. As large-scale ascent from the approaching upper low and jet streak move over the Plains, a lee low should quickly emerge and begin to rapidly deepen over central High Plains. Surface pressure falls and the strong flow aloft will aid in developing strong surface winds over much of the Plains. Hot and dry surface conditions atop drying fuels will set the stage for widespread critical and localized extremely critical fire-weather conditions D2/Monday. ...High Plains... As the main upper low phases with the subtropical jet, 70+ kt mid-level flow will shift eastward and cross the Rockies. The rapidly deepening lee low will force strong west/southwest flow downslope over the High Plains behind a dryline forecast to mix near 100 degrees west. Sustained surface winds of 25-40 mph are possible behind the dryline given the strong pressure falls and enhanced momentum transfer from increasing flow aloft. Minimum RH values are also expected to be critically low, falling to near 10% over much of the High Plains. Widespread dry and receptive fuels, combined with strong wind gusts and very dry surface conditions, will support ubiquitous critical fire-weather concerns from eastern CO and western KS, into parts of the Panhandles, and eastern NM/west TX. Localized extremely critical conditions also appear possible as strong winds continue to increase into the late afternoon and evening hours. The most likely corridor for localized extreme conditions will exist from southeastern CO into parts of western KS and the northwestern Panhandles. Here, the overlap of the strongest flow aloft and the low-level thermal ridge may support occasional surface wind gusts in excess of 50 mph and single digit RH for a few hours during the afternoon. While critical fire-weather concerns are likely over a broad area, substantial uncertainty is present with the eastward extent of fire-weather concerns. NWP guidance, with relation to the position of the dryline, has shown large errors in recent weeks and spread among various solutions remains large. Further refinement of the eastern edge of the Elevated and Critical areas is likely needed in future outlooks. ...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 0204 PM CDT Sun Apr 14 2024 Valid 151200Z - 161200Z ...CRITICAL FIRE WEATHER AREA FOR CENTRAL AND SOUTHERN HIGH PLAINS... The critical area has been expanded based on the latest guidance. RH in the single digits appears likely for a broad portion of the regions. The potential for extremely critical fire weather remains across northeast New Mexico into southeast Colorado and parts of western Kansas. Duration of these conditions will be the primary uncertainty as the most favorable overlap of synoptic features may only be brief. There is some potential for elevated fire weather in parts of northwestern Iowa into southeast South Dakota. Dry air is in place in the upper Midwest and winds will increase ahead of a lifting warm front prior to precipitation arriving during the evening/overnight. With these dry/windy conditions occurring primarily over marginally dry fuels (drier fuels exist to the southwest), the threat may remain localized. ..Wendt.. 04/14/2024 .PREV DISCUSSION... /ISSUED 0207 AM CDT Sun Apr 14 2024/ ...Synopsis... An upper low and strong jet streak are forecast to intensify and eject eastward over the southern and central Rockies D2/Monday. As large-scale ascent from the approaching upper low and jet streak move over the Plains, a lee low should quickly emerge and begin to rapidly deepen over central High Plains. Surface pressure falls and the strong flow aloft will aid in developing strong surface winds over much of the Plains. Hot and dry surface conditions atop drying fuels will set the stage for widespread critical and localized extremely critical fire-weather conditions D2/Monday. ...High Plains... As the main upper low phases with the subtropical jet, 70+ kt mid-level flow will shift eastward and cross the Rockies. The rapidly deepening lee low will force strong west/southwest flow downslope over the High Plains behind a dryline forecast to mix near 100 degrees west. Sustained surface winds of 25-40 mph are possible behind the dryline given the strong pressure falls and enhanced momentum transfer from increasing flow aloft. Minimum RH values are also expected to be critically low, falling to near 10% over much of the High Plains. Widespread dry and receptive fuels, combined with strong wind gusts and very dry surface conditions, will support ubiquitous critical fire-weather concerns from eastern CO and western KS, into parts of the Panhandles, and eastern NM/west TX. Localized extremely critical conditions also appear possible as strong winds continue to increase into the late afternoon and evening hours. The most likely corridor for localized extreme conditions will exist from southeastern CO into parts of western KS and the northwestern Panhandles. Here, the overlap of the strongest flow aloft and the low-level thermal ridge may support occasional surface wind gusts in excess of 50 mph and single digit RH for a few hours during the afternoon. While critical fire-weather concerns are likely over a broad area, substantial uncertainty is present with the eastward extent of fire-weather concerns. NWP guidance, with relation to the position of the dryline, has shown large errors in recent weeks and spread among various solutions remains large. Further refinement of the eastern edge of the Elevated and Critical areas is likely needed in future outlooks. ...Please see www.spc.noaa.gov/fire for graphic product... Read more