SPC Oct 28, 2024 1730 UTC Day 2 Convective Outlook

10 months 3 weeks ago
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 0326 PM CDT Mon Oct 28 2024 Valid 291200Z - 301200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE UPPER MISSISSIPPI AND MIDDLE MISSOURI VALLEYS TO KANSAS/NORTHWESTERN OKLAHOMA... CORRECTED FOR THUNDER AREA REMOVAL IN THE NORTHEAST ...SUMMARY... Thunderstorm development may begin late in the period from the Upper Mississippi Valley area south-southwestward across the Plains. Local/limited risk for hail/wind warrants continuation of Level 1/MRGL risk for Tuesday night. ...Synopsis... A highly amplified flow field aloft will reside across the U.S. Tuesday, as a deep trough slowly crosses the Intermountain West through the period. By Wednesday morning, the trough should extend from the northern High Plains to the Four Corners area. Meanwhile, ridging will amplify in the eastern U.S., in response to the advance of the western trough. At the surface, a cold front will sweep across the Four Corners states through the first half of the period, ahead of the progressing upper system. A frontal wave should evolve over the central High Plains, and is expected to then shift north-northeastward across Nebraska, reaching the southern Minnesota vicinity by 12Z Tuesday morning. This will allow continued eastward advance of the trailing front, which should extend from the Mid Missouri Valley (western Iowa) vicinity south-southwestward to southern New Mexico/far West Texas by the end of the period. ...Upper Mississippi Valley south-southwestward to the northwestern Oklahoma vicinity... Ahead of the sharpening cold front becoming established across the Plains Tuesday/Tuesday night, a warm/modestly moist pre-frontal boundary layer is expected to evolve, beneath a fairly pronounced warm/capping layer aloft. Much of the large-scale ascent associated with the advancing upper system should remain to the cool side of the front, and thus expect the capping layer to be very slow to weaken/erode. Low-level warm advection ahead of the track of the surface low may support some primarily elevated convective development overnight, where modest elevated CAPE may be sufficient to permit a few stronger updrafts. Limited potential for hail nearing severe levels could accompany one or two of the strongest storms. A strong gust cannot be ruled out, should a less-elevated storm nearer the surface boundary evolve. Farther southwestward into the Plains, any potential storm development should be limited to the last 3 or 4 hours of the period, at the earliest -- due to the persistent capping. With that said, given gradually steepening lapse rates/increasing CAPE, and the presence of strong southwesterly flow aloft atop the frontal zone, low/conditional risk for a couple of storms capable of producing marginal hail/wind cannot be ruled out. A such, will retain an elongated Level 1/MRGL risk area across central portions of the country to reflect these potential convective scenarios that may evolve prior to the end of the period. ..Goss.. 10/28/2024 Read more

SPC Oct 28, 2024 1730 UTC Day 2 Convective Outlook

10 months 3 weeks ago
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 0326 PM CDT Mon Oct 28 2024 Valid 291200Z - 301200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE UPPER MISSISSIPPI AND MIDDLE MISSOURI VALLEYS TO KANSAS/NORTHWESTERN OKLAHOMA... CORRECTED FOR THUNDER AREA REMOVAL IN THE NORTHEAST ...SUMMARY... Thunderstorm development may begin late in the period from the Upper Mississippi Valley area south-southwestward across the Plains. Local/limited risk for hail/wind warrants continuation of Level 1/MRGL risk for Tuesday night. ...Synopsis... A highly amplified flow field aloft will reside across the U.S. Tuesday, as a deep trough slowly crosses the Intermountain West through the period. By Wednesday morning, the trough should extend from the northern High Plains to the Four Corners area. Meanwhile, ridging will amplify in the eastern U.S., in response to the advance of the western trough. At the surface, a cold front will sweep across the Four Corners states through the first half of the period, ahead of the progressing upper system. A frontal wave should evolve over the central High Plains, and is expected to then shift north-northeastward across Nebraska, reaching the southern Minnesota vicinity by 12Z Tuesday morning. This will allow continued eastward advance of the trailing front, which should extend from the Mid Missouri Valley (western Iowa) vicinity south-southwestward to southern New Mexico/far West Texas by the end of the period. ...Upper Mississippi Valley south-southwestward to the northwestern Oklahoma vicinity... Ahead of the sharpening cold front becoming established across the Plains Tuesday/Tuesday night, a warm/modestly moist pre-frontal boundary layer is expected to evolve, beneath a fairly pronounced warm/capping layer aloft. Much of the large-scale ascent associated with the advancing upper system should remain to the cool side of the front, and thus expect the capping layer to be very slow to weaken/erode. Low-level warm advection ahead of the track of the surface low may support some primarily elevated convective development overnight, where modest elevated CAPE may be sufficient to permit a few stronger updrafts. Limited potential for hail nearing severe levels could accompany one or two of the strongest storms. A strong gust cannot be ruled out, should a less-elevated storm nearer the surface boundary evolve. Farther southwestward into the Plains, any potential storm development should be limited to the last 3 or 4 hours of the period, at the earliest -- due to the persistent capping. With that said, given gradually steepening lapse rates/increasing CAPE, and the presence of strong southwesterly flow aloft atop the frontal zone, low/conditional risk for a couple of storms capable of producing marginal hail/wind cannot be ruled out. A such, will retain an elongated Level 1/MRGL risk area across central portions of the country to reflect these potential convective scenarios that may evolve prior to the end of the period. ..Goss.. 10/28/2024 Read more

SPC Oct 28, 2024 1730 UTC Day 2 Convective Outlook

10 months 3 weeks ago
SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook CORR 1 NWS Storm Prediction Center Norman OK 0326 PM CDT Mon Oct 28 2024 Valid 291200Z - 301200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM THE UPPER MISSISSIPPI AND MIDDLE MISSOURI VALLEYS TO KANSAS/NORTHWESTERN OKLAHOMA... CORRECTED FOR THUNDER AREA REMOVAL IN THE NORTHEAST ...SUMMARY... Thunderstorm development may begin late in the period from the Upper Mississippi Valley area south-southwestward across the Plains. Local/limited risk for hail/wind warrants continuation of Level 1/MRGL risk for Tuesday night. ...Synopsis... A highly amplified flow field aloft will reside across the U.S. Tuesday, as a deep trough slowly crosses the Intermountain West through the period. By Wednesday morning, the trough should extend from the northern High Plains to the Four Corners area. Meanwhile, ridging will amplify in the eastern U.S., in response to the advance of the western trough. At the surface, a cold front will sweep across the Four Corners states through the first half of the period, ahead of the progressing upper system. A frontal wave should evolve over the central High Plains, and is expected to then shift north-northeastward across Nebraska, reaching the southern Minnesota vicinity by 12Z Tuesday morning. This will allow continued eastward advance of the trailing front, which should extend from the Mid Missouri Valley (western Iowa) vicinity south-southwestward to southern New Mexico/far West Texas by the end of the period. ...Upper Mississippi Valley south-southwestward to the northwestern Oklahoma vicinity... Ahead of the sharpening cold front becoming established across the Plains Tuesday/Tuesday night, a warm/modestly moist pre-frontal boundary layer is expected to evolve, beneath a fairly pronounced warm/capping layer aloft. Much of the large-scale ascent associated with the advancing upper system should remain to the cool side of the front, and thus expect the capping layer to be very slow to weaken/erode. Low-level warm advection ahead of the track of the surface low may support some primarily elevated convective development overnight, where modest elevated CAPE may be sufficient to permit a few stronger updrafts. Limited potential for hail nearing severe levels could accompany one or two of the strongest storms. A strong gust cannot be ruled out, should a less-elevated storm nearer the surface boundary evolve. Farther southwestward into the Plains, any potential storm development should be limited to the last 3 or 4 hours of the period, at the earliest -- due to the persistent capping. With that said, given gradually steepening lapse rates/increasing CAPE, and the presence of strong southwesterly flow aloft atop the frontal zone, low/conditional risk for a couple of storms capable of producing marginal hail/wind cannot be ruled out. A such, will retain an elongated Level 1/MRGL risk area across central portions of the country to reflect these potential convective scenarios that may evolve prior to the end of the period. ..Goss.. 10/28/2024 Read more

SPC Day 2 Fire Weather Outlook

10 months 3 weeks ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Mon Oct 28 2024 Valid 291200Z - 301200Z ...CRITICAL FIRE WEATHER AREA FOR PARTS OF CENTRAL HIGH PLAINS... Downslope warming and favorable timing of the mid-level jet across the central High Plains suggests Critical fire weather is probable in portions of the region. Strong sustained winds (and higher gusts) are still expected farther east. Uncertainty remains rather high in terms of how low RH will fall with continued moisture return northward. The Elevated area has been expanded east to account for some of this uncertainty and the potential for areas along the fringe of the moisture return to be drier than anticipated. Elevated conditions are possible in parts of central/northern Illinois. Models show a drier pocket of air moving over the region by afternoon. Current observations and forecast trajectories support this possibility. Fuels are quite dry and winds will be strong, but uncertainty remains quite large due to cirrus potentially impacting afternoon temperatures. ..Wendt.. 10/28/2024 .PREV DISCUSSION... /ISSUED 0210 AM CDT Mon Oct 28 2024/ ...Synopsis... As the upper trough deepens over the west, strong southwesterly flow aloft will remain over the Rockies and adjacent High Plains. A sub 1000 mb lee low and trailing surface trough will encourage gusty downslope winds of 20-30 mph across eastern CO/NM and parts of western KS, TX and OK. Elevated to near-critical fire-weather conditions are possible. ...High Plains... Surface winds are expected to intensify early in the day south of the lee low across portions of the central High Plains. Heating and downslope warming beneath scattered high clouds will support RH minimums of 15-25%. The overlap of strong winds and low RH will support several hours of elevated to near-critical fire-weather conditions. There remains some uncertainty on the exact areal extent of the fire-weather risk given the narrow corridor of the strongest winds are excepted to align with more limited RH from cloud cover and returning moisture, as well as fuels that are not as dry as farther east. While near-critical conditions are possible, forecast confidence remains too low to include a critical area. The most probable location for sustained critical conditions may be across parts of northeastern and eastern CO, where stronger winds and downslope drying could overlap with more receptive fuels. Farther east, strong southerly winds are likely over parts of central KS and OK. RH values are not expected to be overly low as southerly return flow advects moisture northward. However, pockets of drier air and gusts to 30+ mph could support sporadic locally elevated fire-weather conditions Tuesday afternoon given the exceptionally dry fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook

10 months 3 weeks ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Mon Oct 28 2024 Valid 291200Z - 301200Z ...CRITICAL FIRE WEATHER AREA FOR PARTS OF CENTRAL HIGH PLAINS... Downslope warming and favorable timing of the mid-level jet across the central High Plains suggests Critical fire weather is probable in portions of the region. Strong sustained winds (and higher gusts) are still expected farther east. Uncertainty remains rather high in terms of how low RH will fall with continued moisture return northward. The Elevated area has been expanded east to account for some of this uncertainty and the potential for areas along the fringe of the moisture return to be drier than anticipated. Elevated conditions are possible in parts of central/northern Illinois. Models show a drier pocket of air moving over the region by afternoon. Current observations and forecast trajectories support this possibility. Fuels are quite dry and winds will be strong, but uncertainty remains quite large due to cirrus potentially impacting afternoon temperatures. ..Wendt.. 10/28/2024 .PREV DISCUSSION... /ISSUED 0210 AM CDT Mon Oct 28 2024/ ...Synopsis... As the upper trough deepens over the west, strong southwesterly flow aloft will remain over the Rockies and adjacent High Plains. A sub 1000 mb lee low and trailing surface trough will encourage gusty downslope winds of 20-30 mph across eastern CO/NM and parts of western KS, TX and OK. Elevated to near-critical fire-weather conditions are possible. ...High Plains... Surface winds are expected to intensify early in the day south of the lee low across portions of the central High Plains. Heating and downslope warming beneath scattered high clouds will support RH minimums of 15-25%. The overlap of strong winds and low RH will support several hours of elevated to near-critical fire-weather conditions. There remains some uncertainty on the exact areal extent of the fire-weather risk given the narrow corridor of the strongest winds are excepted to align with more limited RH from cloud cover and returning moisture, as well as fuels that are not as dry as farther east. While near-critical conditions are possible, forecast confidence remains too low to include a critical area. The most probable location for sustained critical conditions may be across parts of northeastern and eastern CO, where stronger winds and downslope drying could overlap with more receptive fuels. Farther east, strong southerly winds are likely over parts of central KS and OK. RH values are not expected to be overly low as southerly return flow advects moisture northward. However, pockets of drier air and gusts to 30+ mph could support sporadic locally elevated fire-weather conditions Tuesday afternoon given the exceptionally dry fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook

10 months 3 weeks ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Mon Oct 28 2024 Valid 291200Z - 301200Z ...CRITICAL FIRE WEATHER AREA FOR PARTS OF CENTRAL HIGH PLAINS... Downslope warming and favorable timing of the mid-level jet across the central High Plains suggests Critical fire weather is probable in portions of the region. Strong sustained winds (and higher gusts) are still expected farther east. Uncertainty remains rather high in terms of how low RH will fall with continued moisture return northward. The Elevated area has been expanded east to account for some of this uncertainty and the potential for areas along the fringe of the moisture return to be drier than anticipated. Elevated conditions are possible in parts of central/northern Illinois. Models show a drier pocket of air moving over the region by afternoon. Current observations and forecast trajectories support this possibility. Fuels are quite dry and winds will be strong, but uncertainty remains quite large due to cirrus potentially impacting afternoon temperatures. ..Wendt.. 10/28/2024 .PREV DISCUSSION... /ISSUED 0210 AM CDT Mon Oct 28 2024/ ...Synopsis... As the upper trough deepens over the west, strong southwesterly flow aloft will remain over the Rockies and adjacent High Plains. A sub 1000 mb lee low and trailing surface trough will encourage gusty downslope winds of 20-30 mph across eastern CO/NM and parts of western KS, TX and OK. Elevated to near-critical fire-weather conditions are possible. ...High Plains... Surface winds are expected to intensify early in the day south of the lee low across portions of the central High Plains. Heating and downslope warming beneath scattered high clouds will support RH minimums of 15-25%. The overlap of strong winds and low RH will support several hours of elevated to near-critical fire-weather conditions. There remains some uncertainty on the exact areal extent of the fire-weather risk given the narrow corridor of the strongest winds are excepted to align with more limited RH from cloud cover and returning moisture, as well as fuels that are not as dry as farther east. While near-critical conditions are possible, forecast confidence remains too low to include a critical area. The most probable location for sustained critical conditions may be across parts of northeastern and eastern CO, where stronger winds and downslope drying could overlap with more receptive fuels. Farther east, strong southerly winds are likely over parts of central KS and OK. RH values are not expected to be overly low as southerly return flow advects moisture northward. However, pockets of drier air and gusts to 30+ mph could support sporadic locally elevated fire-weather conditions Tuesday afternoon given the exceptionally dry fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook

10 months 3 weeks ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Mon Oct 28 2024 Valid 291200Z - 301200Z ...CRITICAL FIRE WEATHER AREA FOR PARTS OF CENTRAL HIGH PLAINS... Downslope warming and favorable timing of the mid-level jet across the central High Plains suggests Critical fire weather is probable in portions of the region. Strong sustained winds (and higher gusts) are still expected farther east. Uncertainty remains rather high in terms of how low RH will fall with continued moisture return northward. The Elevated area has been expanded east to account for some of this uncertainty and the potential for areas along the fringe of the moisture return to be drier than anticipated. Elevated conditions are possible in parts of central/northern Illinois. Models show a drier pocket of air moving over the region by afternoon. Current observations and forecast trajectories support this possibility. Fuels are quite dry and winds will be strong, but uncertainty remains quite large due to cirrus potentially impacting afternoon temperatures. ..Wendt.. 10/28/2024 .PREV DISCUSSION... /ISSUED 0210 AM CDT Mon Oct 28 2024/ ...Synopsis... As the upper trough deepens over the west, strong southwesterly flow aloft will remain over the Rockies and adjacent High Plains. A sub 1000 mb lee low and trailing surface trough will encourage gusty downslope winds of 20-30 mph across eastern CO/NM and parts of western KS, TX and OK. Elevated to near-critical fire-weather conditions are possible. ...High Plains... Surface winds are expected to intensify early in the day south of the lee low across portions of the central High Plains. Heating and downslope warming beneath scattered high clouds will support RH minimums of 15-25%. The overlap of strong winds and low RH will support several hours of elevated to near-critical fire-weather conditions. There remains some uncertainty on the exact areal extent of the fire-weather risk given the narrow corridor of the strongest winds are excepted to align with more limited RH from cloud cover and returning moisture, as well as fuels that are not as dry as farther east. While near-critical conditions are possible, forecast confidence remains too low to include a critical area. The most probable location for sustained critical conditions may be across parts of northeastern and eastern CO, where stronger winds and downslope drying could overlap with more receptive fuels. Farther east, strong southerly winds are likely over parts of central KS and OK. RH values are not expected to be overly low as southerly return flow advects moisture northward. However, pockets of drier air and gusts to 30+ mph could support sporadic locally elevated fire-weather conditions Tuesday afternoon given the exceptionally dry fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook

10 months 3 weeks ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Mon Oct 28 2024 Valid 291200Z - 301200Z ...CRITICAL FIRE WEATHER AREA FOR PARTS OF CENTRAL HIGH PLAINS... Downslope warming and favorable timing of the mid-level jet across the central High Plains suggests Critical fire weather is probable in portions of the region. Strong sustained winds (and higher gusts) are still expected farther east. Uncertainty remains rather high in terms of how low RH will fall with continued moisture return northward. The Elevated area has been expanded east to account for some of this uncertainty and the potential for areas along the fringe of the moisture return to be drier than anticipated. Elevated conditions are possible in parts of central/northern Illinois. Models show a drier pocket of air moving over the region by afternoon. Current observations and forecast trajectories support this possibility. Fuels are quite dry and winds will be strong, but uncertainty remains quite large due to cirrus potentially impacting afternoon temperatures. ..Wendt.. 10/28/2024 .PREV DISCUSSION... /ISSUED 0210 AM CDT Mon Oct 28 2024/ ...Synopsis... As the upper trough deepens over the west, strong southwesterly flow aloft will remain over the Rockies and adjacent High Plains. A sub 1000 mb lee low and trailing surface trough will encourage gusty downslope winds of 20-30 mph across eastern CO/NM and parts of western KS, TX and OK. Elevated to near-critical fire-weather conditions are possible. ...High Plains... Surface winds are expected to intensify early in the day south of the lee low across portions of the central High Plains. Heating and downslope warming beneath scattered high clouds will support RH minimums of 15-25%. The overlap of strong winds and low RH will support several hours of elevated to near-critical fire-weather conditions. There remains some uncertainty on the exact areal extent of the fire-weather risk given the narrow corridor of the strongest winds are excepted to align with more limited RH from cloud cover and returning moisture, as well as fuels that are not as dry as farther east. While near-critical conditions are possible, forecast confidence remains too low to include a critical area. The most probable location for sustained critical conditions may be across parts of northeastern and eastern CO, where stronger winds and downslope drying could overlap with more receptive fuels. Farther east, strong southerly winds are likely over parts of central KS and OK. RH values are not expected to be overly low as southerly return flow advects moisture northward. However, pockets of drier air and gusts to 30+ mph could support sporadic locally elevated fire-weather conditions Tuesday afternoon given the exceptionally dry fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook

10 months 3 weeks ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Mon Oct 28 2024 Valid 291200Z - 301200Z ...CRITICAL FIRE WEATHER AREA FOR PARTS OF CENTRAL HIGH PLAINS... Downslope warming and favorable timing of the mid-level jet across the central High Plains suggests Critical fire weather is probable in portions of the region. Strong sustained winds (and higher gusts) are still expected farther east. Uncertainty remains rather high in terms of how low RH will fall with continued moisture return northward. The Elevated area has been expanded east to account for some of this uncertainty and the potential for areas along the fringe of the moisture return to be drier than anticipated. Elevated conditions are possible in parts of central/northern Illinois. Models show a drier pocket of air moving over the region by afternoon. Current observations and forecast trajectories support this possibility. Fuels are quite dry and winds will be strong, but uncertainty remains quite large due to cirrus potentially impacting afternoon temperatures. ..Wendt.. 10/28/2024 .PREV DISCUSSION... /ISSUED 0210 AM CDT Mon Oct 28 2024/ ...Synopsis... As the upper trough deepens over the west, strong southwesterly flow aloft will remain over the Rockies and adjacent High Plains. A sub 1000 mb lee low and trailing surface trough will encourage gusty downslope winds of 20-30 mph across eastern CO/NM and parts of western KS, TX and OK. Elevated to near-critical fire-weather conditions are possible. ...High Plains... Surface winds are expected to intensify early in the day south of the lee low across portions of the central High Plains. Heating and downslope warming beneath scattered high clouds will support RH minimums of 15-25%. The overlap of strong winds and low RH will support several hours of elevated to near-critical fire-weather conditions. There remains some uncertainty on the exact areal extent of the fire-weather risk given the narrow corridor of the strongest winds are excepted to align with more limited RH from cloud cover and returning moisture, as well as fuels that are not as dry as farther east. While near-critical conditions are possible, forecast confidence remains too low to include a critical area. The most probable location for sustained critical conditions may be across parts of northeastern and eastern CO, where stronger winds and downslope drying could overlap with more receptive fuels. Farther east, strong southerly winds are likely over parts of central KS and OK. RH values are not expected to be overly low as southerly return flow advects moisture northward. However, pockets of drier air and gusts to 30+ mph could support sporadic locally elevated fire-weather conditions Tuesday afternoon given the exceptionally dry fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook

10 months 3 weeks ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0254 PM CDT Mon Oct 28 2024 Valid 291200Z - 301200Z ...CRITICAL FIRE WEATHER AREA FOR PARTS OF CENTRAL HIGH PLAINS... Downslope warming and favorable timing of the mid-level jet across the central High Plains suggests Critical fire weather is probable in portions of the region. Strong sustained winds (and higher gusts) are still expected farther east. Uncertainty remains rather high in terms of how low RH will fall with continued moisture return northward. The Elevated area has been expanded east to account for some of this uncertainty and the potential for areas along the fringe of the moisture return to be drier than anticipated. Elevated conditions are possible in parts of central/northern Illinois. Models show a drier pocket of air moving over the region by afternoon. Current observations and forecast trajectories support this possibility. Fuels are quite dry and winds will be strong, but uncertainty remains quite large due to cirrus potentially impacting afternoon temperatures. ..Wendt.. 10/28/2024 .PREV DISCUSSION... /ISSUED 0210 AM CDT Mon Oct 28 2024/ ...Synopsis... As the upper trough deepens over the west, strong southwesterly flow aloft will remain over the Rockies and adjacent High Plains. A sub 1000 mb lee low and trailing surface trough will encourage gusty downslope winds of 20-30 mph across eastern CO/NM and parts of western KS, TX and OK. Elevated to near-critical fire-weather conditions are possible. ...High Plains... Surface winds are expected to intensify early in the day south of the lee low across portions of the central High Plains. Heating and downslope warming beneath scattered high clouds will support RH minimums of 15-25%. The overlap of strong winds and low RH will support several hours of elevated to near-critical fire-weather conditions. There remains some uncertainty on the exact areal extent of the fire-weather risk given the narrow corridor of the strongest winds are excepted to align with more limited RH from cloud cover and returning moisture, as well as fuels that are not as dry as farther east. While near-critical conditions are possible, forecast confidence remains too low to include a critical area. The most probable location for sustained critical conditions may be across parts of northeastern and eastern CO, where stronger winds and downslope drying could overlap with more receptive fuels. Farther east, strong southerly winds are likely over parts of central KS and OK. RH values are not expected to be overly low as southerly return flow advects moisture northward. However, pockets of drier air and gusts to 30+ mph could support sporadic locally elevated fire-weather conditions Tuesday afternoon given the exceptionally dry fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Oct 28, 2024 2000 UTC Day 1 Convective Outlook

10 months 3 weeks ago
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0244 PM CDT Mon Oct 28 2024 Valid 282000Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today and tonight. ...20Z Update... The primary change to this outlook was to remove thunder probabilities over portions of the Pacific Northwest. Stronger forcing for ascent continues to drift eastward in tandem with the upper trough that is now shifting toward the Interior West. Otherwise, the previous forecast (see below) remains on track. ..Squitieri.. 10/28/2024 .PREV DISCUSSION... /ISSUED 1124 AM CDT Mon Oct 28 2024/ ...Synopsis and Discussion... An upper trough will amplify further today as it moves from the eastern Pacific across the western states. Low-topped showers across parts of coastal WA/OR may be capable of producing occasional lightning flashes, as mid-level temperatures beneath the upper trough remain rather cool, which is supporting weak MUCAPE. But, better forcing for ascent preceding the upper trough will overspread portions of the Great Basin and central Rockies through the period, where isolated thunderstorms may occur even though moisture will be quite limited. A separate area of isolated to scattered thunderstorm potential remains evident across parts of the Great Lakes tonight, as warm/moist advection increases in tandem with a strengthening low-level jet. Weak instability will limit the severe threat across all these regions, and severe thunderstorms are not forecast. Read more

SPC Oct 28, 2024 2000 UTC Day 1 Convective Outlook

10 months 3 weeks ago
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0244 PM CDT Mon Oct 28 2024 Valid 282000Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today and tonight. ...20Z Update... The primary change to this outlook was to remove thunder probabilities over portions of the Pacific Northwest. Stronger forcing for ascent continues to drift eastward in tandem with the upper trough that is now shifting toward the Interior West. Otherwise, the previous forecast (see below) remains on track. ..Squitieri.. 10/28/2024 .PREV DISCUSSION... /ISSUED 1124 AM CDT Mon Oct 28 2024/ ...Synopsis and Discussion... An upper trough will amplify further today as it moves from the eastern Pacific across the western states. Low-topped showers across parts of coastal WA/OR may be capable of producing occasional lightning flashes, as mid-level temperatures beneath the upper trough remain rather cool, which is supporting weak MUCAPE. But, better forcing for ascent preceding the upper trough will overspread portions of the Great Basin and central Rockies through the period, where isolated thunderstorms may occur even though moisture will be quite limited. A separate area of isolated to scattered thunderstorm potential remains evident across parts of the Great Lakes tonight, as warm/moist advection increases in tandem with a strengthening low-level jet. Weak instability will limit the severe threat across all these regions, and severe thunderstorms are not forecast. Read more

SPC Oct 28, 2024 2000 UTC Day 1 Convective Outlook

10 months 3 weeks ago
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0244 PM CDT Mon Oct 28 2024 Valid 282000Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today and tonight. ...20Z Update... The primary change to this outlook was to remove thunder probabilities over portions of the Pacific Northwest. Stronger forcing for ascent continues to drift eastward in tandem with the upper trough that is now shifting toward the Interior West. Otherwise, the previous forecast (see below) remains on track. ..Squitieri.. 10/28/2024 .PREV DISCUSSION... /ISSUED 1124 AM CDT Mon Oct 28 2024/ ...Synopsis and Discussion... An upper trough will amplify further today as it moves from the eastern Pacific across the western states. Low-topped showers across parts of coastal WA/OR may be capable of producing occasional lightning flashes, as mid-level temperatures beneath the upper trough remain rather cool, which is supporting weak MUCAPE. But, better forcing for ascent preceding the upper trough will overspread portions of the Great Basin and central Rockies through the period, where isolated thunderstorms may occur even though moisture will be quite limited. A separate area of isolated to scattered thunderstorm potential remains evident across parts of the Great Lakes tonight, as warm/moist advection increases in tandem with a strengthening low-level jet. Weak instability will limit the severe threat across all these regions, and severe thunderstorms are not forecast. Read more

SPC Oct 28, 2024 2000 UTC Day 1 Convective Outlook

10 months 3 weeks ago
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0244 PM CDT Mon Oct 28 2024 Valid 282000Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today and tonight. ...20Z Update... The primary change to this outlook was to remove thunder probabilities over portions of the Pacific Northwest. Stronger forcing for ascent continues to drift eastward in tandem with the upper trough that is now shifting toward the Interior West. Otherwise, the previous forecast (see below) remains on track. ..Squitieri.. 10/28/2024 .PREV DISCUSSION... /ISSUED 1124 AM CDT Mon Oct 28 2024/ ...Synopsis and Discussion... An upper trough will amplify further today as it moves from the eastern Pacific across the western states. Low-topped showers across parts of coastal WA/OR may be capable of producing occasional lightning flashes, as mid-level temperatures beneath the upper trough remain rather cool, which is supporting weak MUCAPE. But, better forcing for ascent preceding the upper trough will overspread portions of the Great Basin and central Rockies through the period, where isolated thunderstorms may occur even though moisture will be quite limited. A separate area of isolated to scattered thunderstorm potential remains evident across parts of the Great Lakes tonight, as warm/moist advection increases in tandem with a strengthening low-level jet. Weak instability will limit the severe threat across all these regions, and severe thunderstorms are not forecast. Read more

SPC Oct 28, 2024 2000 UTC Day 1 Convective Outlook

10 months 3 weeks ago
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0244 PM CDT Mon Oct 28 2024 Valid 282000Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today and tonight. ...20Z Update... The primary change to this outlook was to remove thunder probabilities over portions of the Pacific Northwest. Stronger forcing for ascent continues to drift eastward in tandem with the upper trough that is now shifting toward the Interior West. Otherwise, the previous forecast (see below) remains on track. ..Squitieri.. 10/28/2024 .PREV DISCUSSION... /ISSUED 1124 AM CDT Mon Oct 28 2024/ ...Synopsis and Discussion... An upper trough will amplify further today as it moves from the eastern Pacific across the western states. Low-topped showers across parts of coastal WA/OR may be capable of producing occasional lightning flashes, as mid-level temperatures beneath the upper trough remain rather cool, which is supporting weak MUCAPE. But, better forcing for ascent preceding the upper trough will overspread portions of the Great Basin and central Rockies through the period, where isolated thunderstorms may occur even though moisture will be quite limited. A separate area of isolated to scattered thunderstorm potential remains evident across parts of the Great Lakes tonight, as warm/moist advection increases in tandem with a strengthening low-level jet. Weak instability will limit the severe threat across all these regions, and severe thunderstorms are not forecast. Read more

SPC Oct 28, 2024 2000 UTC Day 1 Convective Outlook

10 months 3 weeks ago
SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0244 PM CDT Mon Oct 28 2024 Valid 282000Z - 291200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected today and tonight. ...20Z Update... The primary change to this outlook was to remove thunder probabilities over portions of the Pacific Northwest. Stronger forcing for ascent continues to drift eastward in tandem with the upper trough that is now shifting toward the Interior West. Otherwise, the previous forecast (see below) remains on track. ..Squitieri.. 10/28/2024 .PREV DISCUSSION... /ISSUED 1124 AM CDT Mon Oct 28 2024/ ...Synopsis and Discussion... An upper trough will amplify further today as it moves from the eastern Pacific across the western states. Low-topped showers across parts of coastal WA/OR may be capable of producing occasional lightning flashes, as mid-level temperatures beneath the upper trough remain rather cool, which is supporting weak MUCAPE. But, better forcing for ascent preceding the upper trough will overspread portions of the Great Basin and central Rockies through the period, where isolated thunderstorms may occur even though moisture will be quite limited. A separate area of isolated to scattered thunderstorm potential remains evident across parts of the Great Lakes tonight, as warm/moist advection increases in tandem with a strengthening low-level jet. Weak instability will limit the severe threat across all these regions, and severe thunderstorms are not forecast. Read more

SPC Oct 28, 2024 1930 UTC Day 3 Severe Thunderstorm Outlook

10 months 3 weeks ago
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0219 PM CDT Mon Oct 28 2024 Valid 301200Z - 311200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTHERN IOWA AND SOUTHEASTERN NEBRASKA SOUTHWESTWARD TO NORTH TEXAS... ...SUMMARY... Strong/locally severe thunderstorms, capable of producing severe wind gusts and large hail, are expected to develop Wednesday from the southern Plains north-northeastward to the Middle Mississippi Valley/Upper Midwest. ...Synopsis... An upper trough moving out of the interior West is forecast to eject northeastward across the central U.S. Wednesday, shunted from its prior, more eastward trajectory by stout ridging over the eastern CONUS. At the surface, steady eastward advance of a cold front across the central third of the country is expected. By the end of the period (early Thursday morning), the boundary should extend from the Upper Great Lakes region southwestward across the Mid Mississippi Valley and Ozarks region, to central Texas. ...Upper Midwest to Texas... Thunderstorm development is expected to occur -- potentially early in the period -- along the advancing cold front, as lapse rates gradually steepen atop a sufficiently moist/gradually warming boundary layer. The more substantial destabilization is expected to evolve from roughly Kansas southward, while the strongest/deepest forcing for ascent should occur from roughly Kansas northward. As such, initial convective development is expected in the vicinity of the Middle Missouri Valley during the morning, and spreading northeastward into the progressively weaker-CAPE environment into the upper Mississippi Valley/western Upper Great Lakes area. Despite the more limited CAPE, however, strong southwesterly flow aloft -- increasing with height -- will result in shear supporting at least isolated stronger/potentially severe storms. Hail and locally damaging wind gusts will be the primary risks, spreading eastward with time as the front advances. Threat should gradually diminish after dark, with the loss of heating/diminishing CAPE. Farther south, convective initiation should occur later, given weaker forcing for ascent, and residual capping. Storms that do initiate will occur in a thermodynamic and kinematic environment favoring rotating updrafts, and thus expect potential for large hail and locally damaging gusts with stronger storms. A tornado or two may also occur, though some upscale growth is expected to occur with time, potentially limiting this risk. While some severe potential may continue into the overnight hours, weakening CAPE should correspond to a gradual decrease in severe potential through 31/12Z. ..Goss.. 10/28/2024 Read more

SPC Oct 28, 2024 1930 UTC Day 3 Severe Thunderstorm Outlook

10 months 3 weeks ago
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0219 PM CDT Mon Oct 28 2024 Valid 301200Z - 311200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTHERN IOWA AND SOUTHEASTERN NEBRASKA SOUTHWESTWARD TO NORTH TEXAS... ...SUMMARY... Strong/locally severe thunderstorms, capable of producing severe wind gusts and large hail, are expected to develop Wednesday from the southern Plains north-northeastward to the Middle Mississippi Valley/Upper Midwest. ...Synopsis... An upper trough moving out of the interior West is forecast to eject northeastward across the central U.S. Wednesday, shunted from its prior, more eastward trajectory by stout ridging over the eastern CONUS. At the surface, steady eastward advance of a cold front across the central third of the country is expected. By the end of the period (early Thursday morning), the boundary should extend from the Upper Great Lakes region southwestward across the Mid Mississippi Valley and Ozarks region, to central Texas. ...Upper Midwest to Texas... Thunderstorm development is expected to occur -- potentially early in the period -- along the advancing cold front, as lapse rates gradually steepen atop a sufficiently moist/gradually warming boundary layer. The more substantial destabilization is expected to evolve from roughly Kansas southward, while the strongest/deepest forcing for ascent should occur from roughly Kansas northward. As such, initial convective development is expected in the vicinity of the Middle Missouri Valley during the morning, and spreading northeastward into the progressively weaker-CAPE environment into the upper Mississippi Valley/western Upper Great Lakes area. Despite the more limited CAPE, however, strong southwesterly flow aloft -- increasing with height -- will result in shear supporting at least isolated stronger/potentially severe storms. Hail and locally damaging wind gusts will be the primary risks, spreading eastward with time as the front advances. Threat should gradually diminish after dark, with the loss of heating/diminishing CAPE. Farther south, convective initiation should occur later, given weaker forcing for ascent, and residual capping. Storms that do initiate will occur in a thermodynamic and kinematic environment favoring rotating updrafts, and thus expect potential for large hail and locally damaging gusts with stronger storms. A tornado or two may also occur, though some upscale growth is expected to occur with time, potentially limiting this risk. While some severe potential may continue into the overnight hours, weakening CAPE should correspond to a gradual decrease in severe potential through 31/12Z. ..Goss.. 10/28/2024 Read more

SPC Oct 28, 2024 1930 UTC Day 3 Severe Thunderstorm Outlook

10 months 3 weeks ago
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0219 PM CDT Mon Oct 28 2024 Valid 301200Z - 311200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTHERN IOWA AND SOUTHEASTERN NEBRASKA SOUTHWESTWARD TO NORTH TEXAS... ...SUMMARY... Strong/locally severe thunderstorms, capable of producing severe wind gusts and large hail, are expected to develop Wednesday from the southern Plains north-northeastward to the Middle Mississippi Valley/Upper Midwest. ...Synopsis... An upper trough moving out of the interior West is forecast to eject northeastward across the central U.S. Wednesday, shunted from its prior, more eastward trajectory by stout ridging over the eastern CONUS. At the surface, steady eastward advance of a cold front across the central third of the country is expected. By the end of the period (early Thursday morning), the boundary should extend from the Upper Great Lakes region southwestward across the Mid Mississippi Valley and Ozarks region, to central Texas. ...Upper Midwest to Texas... Thunderstorm development is expected to occur -- potentially early in the period -- along the advancing cold front, as lapse rates gradually steepen atop a sufficiently moist/gradually warming boundary layer. The more substantial destabilization is expected to evolve from roughly Kansas southward, while the strongest/deepest forcing for ascent should occur from roughly Kansas northward. As such, initial convective development is expected in the vicinity of the Middle Missouri Valley during the morning, and spreading northeastward into the progressively weaker-CAPE environment into the upper Mississippi Valley/western Upper Great Lakes area. Despite the more limited CAPE, however, strong southwesterly flow aloft -- increasing with height -- will result in shear supporting at least isolated stronger/potentially severe storms. Hail and locally damaging wind gusts will be the primary risks, spreading eastward with time as the front advances. Threat should gradually diminish after dark, with the loss of heating/diminishing CAPE. Farther south, convective initiation should occur later, given weaker forcing for ascent, and residual capping. Storms that do initiate will occur in a thermodynamic and kinematic environment favoring rotating updrafts, and thus expect potential for large hail and locally damaging gusts with stronger storms. A tornado or two may also occur, though some upscale growth is expected to occur with time, potentially limiting this risk. While some severe potential may continue into the overnight hours, weakening CAPE should correspond to a gradual decrease in severe potential through 31/12Z. ..Goss.. 10/28/2024 Read more

SPC Oct 28, 2024 1930 UTC Day 3 Severe Thunderstorm Outlook

10 months 3 weeks ago
SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0219 PM CDT Mon Oct 28 2024 Valid 301200Z - 311200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTHERN IOWA AND SOUTHEASTERN NEBRASKA SOUTHWESTWARD TO NORTH TEXAS... ...SUMMARY... Strong/locally severe thunderstorms, capable of producing severe wind gusts and large hail, are expected to develop Wednesday from the southern Plains north-northeastward to the Middle Mississippi Valley/Upper Midwest. ...Synopsis... An upper trough moving out of the interior West is forecast to eject northeastward across the central U.S. Wednesday, shunted from its prior, more eastward trajectory by stout ridging over the eastern CONUS. At the surface, steady eastward advance of a cold front across the central third of the country is expected. By the end of the period (early Thursday morning), the boundary should extend from the Upper Great Lakes region southwestward across the Mid Mississippi Valley and Ozarks region, to central Texas. ...Upper Midwest to Texas... Thunderstorm development is expected to occur -- potentially early in the period -- along the advancing cold front, as lapse rates gradually steepen atop a sufficiently moist/gradually warming boundary layer. The more substantial destabilization is expected to evolve from roughly Kansas southward, while the strongest/deepest forcing for ascent should occur from roughly Kansas northward. As such, initial convective development is expected in the vicinity of the Middle Missouri Valley during the morning, and spreading northeastward into the progressively weaker-CAPE environment into the upper Mississippi Valley/western Upper Great Lakes area. Despite the more limited CAPE, however, strong southwesterly flow aloft -- increasing with height -- will result in shear supporting at least isolated stronger/potentially severe storms. Hail and locally damaging wind gusts will be the primary risks, spreading eastward with time as the front advances. Threat should gradually diminish after dark, with the loss of heating/diminishing CAPE. Farther south, convective initiation should occur later, given weaker forcing for ascent, and residual capping. Storms that do initiate will occur in a thermodynamic and kinematic environment favoring rotating updrafts, and thus expect potential for large hail and locally damaging gusts with stronger storms. A tornado or two may also occur, though some upscale growth is expected to occur with time, potentially limiting this risk. While some severe potential may continue into the overnight hours, weakening CAPE should correspond to a gradual decrease in severe potential through 31/12Z. ..Goss.. 10/28/2024 Read more