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SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1227 PM CDT Fri Nov 01 2024 Valid 021200Z - 031200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE PERMIAN BASIN VICINITY EAST-NORTHEASTWARD INTO SOUTHWESTERN OKLAHOMA... ...SUMMARY... Isolated severe storms are expected Saturday and Saturday night across parts of the southern Great Plains. The most likely corridor for a couple tornadoes and large hail is across parts of the Permian Basin and South Plains of Texas during the late afternoon and early evening. ...Synopsis... Digging/intensification -- and gradual/steady progression -- of the western U.S. upper trough is expected Saturday. As this system shifts from the West Coast states across the Great Basin and into the Desert Southwest, substantial downstream mid-level height falls will occur across the central and southern Plains. At the surface, a remnant baroclinic zone -- extending from Texas eastward across the Southeast -- will mark the northern extent of the moist Gulf low-level airmass. This boundary -- in response to persistent southeasterly low-level flow -- should tend to retreat northwestward across Texas/Oklahoma, though likely to become impeded by convective outflow. The result will likely become a convectively reinforced boundary extending from the Permian Basin vicinity east-northeastward into Oklahoma, which will focus persistent, regenerative convection and some attendant severe risk through the period. ...Transpecos region and southeastern New Mexico northeastward into central and northern Oklahoma... Showers and thunderstorms are forecast to be ongoing at the start of the period from southeastern New Mexico northeastward into southern Kansas, with potentially some local/low-end severe risk on the southern fringe of this convection. South of the convection, some heating/destabilization is expected -- particularly across the Transpecos/Permian Basin region. Here, an afternoon increase in convection -- likely in the form of supercells -- is expected to occur. Here, large hail will be possible, along with potential for locally damaging winds, and a couple of tornadoes. Into the evening, convection should increase in coverage -- likely evolving into multiple linear bands, as a low-level jet increases. Though instability should remain lesser with northeastward extent into Oklahoma, owing to relatively weak lapse rates, multiple rounds of banded convection should be accompanied by risk for locally strong wind gusts, along with marginal hail and potentially a tornado or two. This potential should persist well into the overnight hours. ..Goss.. 11/01/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1227 PM CDT Fri Nov 01 2024 Valid 021200Z - 031200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE PERMIAN BASIN VICINITY EAST-NORTHEASTWARD INTO SOUTHWESTERN OKLAHOMA... ...SUMMARY... Isolated severe storms are expected Saturday and Saturday night across parts of the southern Great Plains. The most likely corridor for a couple tornadoes and large hail is across parts of the Permian Basin and South Plains of Texas during the late afternoon and early evening. ...Synopsis... Digging/intensification -- and gradual/steady progression -- of the western U.S. upper trough is expected Saturday. As this system shifts from the West Coast states across the Great Basin and into the Desert Southwest, substantial downstream mid-level height falls will occur across the central and southern Plains. At the surface, a remnant baroclinic zone -- extending from Texas eastward across the Southeast -- will mark the northern extent of the moist Gulf low-level airmass. This boundary -- in response to persistent southeasterly low-level flow -- should tend to retreat northwestward across Texas/Oklahoma, though likely to become impeded by convective outflow. The result will likely become a convectively reinforced boundary extending from the Permian Basin vicinity east-northeastward into Oklahoma, which will focus persistent, regenerative convection and some attendant severe risk through the period. ...Transpecos region and southeastern New Mexico northeastward into central and northern Oklahoma... Showers and thunderstorms are forecast to be ongoing at the start of the period from southeastern New Mexico northeastward into southern Kansas, with potentially some local/low-end severe risk on the southern fringe of this convection. South of the convection, some heating/destabilization is expected -- particularly across the Transpecos/Permian Basin region. Here, an afternoon increase in convection -- likely in the form of supercells -- is expected to occur. Here, large hail will be possible, along with potential for locally damaging winds, and a couple of tornadoes. Into the evening, convection should increase in coverage -- likely evolving into multiple linear bands, as a low-level jet increases. Though instability should remain lesser with northeastward extent into Oklahoma, owing to relatively weak lapse rates, multiple rounds of banded convection should be accompanied by risk for locally strong wind gusts, along with marginal hail and potentially a tornado or two. This potential should persist well into the overnight hours. ..Goss.. 11/01/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1227 PM CDT Fri Nov 01 2024 Valid 021200Z - 031200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE PERMIAN BASIN VICINITY EAST-NORTHEASTWARD INTO SOUTHWESTERN OKLAHOMA... ...SUMMARY... Isolated severe storms are expected Saturday and Saturday night across parts of the southern Great Plains. The most likely corridor for a couple tornadoes and large hail is across parts of the Permian Basin and South Plains of Texas during the late afternoon and early evening. ...Synopsis... Digging/intensification -- and gradual/steady progression -- of the western U.S. upper trough is expected Saturday. As this system shifts from the West Coast states across the Great Basin and into the Desert Southwest, substantial downstream mid-level height falls will occur across the central and southern Plains. At the surface, a remnant baroclinic zone -- extending from Texas eastward across the Southeast -- will mark the northern extent of the moist Gulf low-level airmass. This boundary -- in response to persistent southeasterly low-level flow -- should tend to retreat northwestward across Texas/Oklahoma, though likely to become impeded by convective outflow. The result will likely become a convectively reinforced boundary extending from the Permian Basin vicinity east-northeastward into Oklahoma, which will focus persistent, regenerative convection and some attendant severe risk through the period. ...Transpecos region and southeastern New Mexico northeastward into central and northern Oklahoma... Showers and thunderstorms are forecast to be ongoing at the start of the period from southeastern New Mexico northeastward into southern Kansas, with potentially some local/low-end severe risk on the southern fringe of this convection. South of the convection, some heating/destabilization is expected -- particularly across the Transpecos/Permian Basin region. Here, an afternoon increase in convection -- likely in the form of supercells -- is expected to occur. Here, large hail will be possible, along with potential for locally damaging winds, and a couple of tornadoes. Into the evening, convection should increase in coverage -- likely evolving into multiple linear bands, as a low-level jet increases. Though instability should remain lesser with northeastward extent into Oklahoma, owing to relatively weak lapse rates, multiple rounds of banded convection should be accompanied by risk for locally strong wind gusts, along with marginal hail and potentially a tornado or two. This potential should persist well into the overnight hours. ..Goss.. 11/01/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1227 PM CDT Fri Nov 01 2024 Valid 021200Z - 031200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE PERMIAN BASIN VICINITY EAST-NORTHEASTWARD INTO SOUTHWESTERN OKLAHOMA... ...SUMMARY... Isolated severe storms are expected Saturday and Saturday night across parts of the southern Great Plains. The most likely corridor for a couple tornadoes and large hail is across parts of the Permian Basin and South Plains of Texas during the late afternoon and early evening. ...Synopsis... Digging/intensification -- and gradual/steady progression -- of the western U.S. upper trough is expected Saturday. As this system shifts from the West Coast states across the Great Basin and into the Desert Southwest, substantial downstream mid-level height falls will occur across the central and southern Plains. At the surface, a remnant baroclinic zone -- extending from Texas eastward across the Southeast -- will mark the northern extent of the moist Gulf low-level airmass. This boundary -- in response to persistent southeasterly low-level flow -- should tend to retreat northwestward across Texas/Oklahoma, though likely to become impeded by convective outflow. The result will likely become a convectively reinforced boundary extending from the Permian Basin vicinity east-northeastward into Oklahoma, which will focus persistent, regenerative convection and some attendant severe risk through the period. ...Transpecos region and southeastern New Mexico northeastward into central and northern Oklahoma... Showers and thunderstorms are forecast to be ongoing at the start of the period from southeastern New Mexico northeastward into southern Kansas, with potentially some local/low-end severe risk on the southern fringe of this convection. South of the convection, some heating/destabilization is expected -- particularly across the Transpecos/Permian Basin region. Here, an afternoon increase in convection -- likely in the form of supercells -- is expected to occur. Here, large hail will be possible, along with potential for locally damaging winds, and a couple of tornadoes. Into the evening, convection should increase in coverage -- likely evolving into multiple linear bands, as a low-level jet increases. Though instability should remain lesser with northeastward extent into Oklahoma, owing to relatively weak lapse rates, multiple rounds of banded convection should be accompanied by risk for locally strong wind gusts, along with marginal hail and potentially a tornado or two. This potential should persist well into the overnight hours. ..Goss.. 11/01/2024 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1126 AM CDT Fri Nov 01 2024 Valid 011700Z - 021200Z The primary changes made to the Day 1 Fire Weather Outlook Update was to expand Elevated highlights into southern Pennsylvania, and northeast to portions of coastal New England. In these areas ahead of the cold front, clearing skies are leading to rapid boundary-layer mixing and lowering of RH. Sustained surface winds are already reaching 20 mph in spots, with higher gusts, and short-range guidance consensus suggests that RH should drop to 30-35 percent RH by mid-afternoon. As such, Elevated fire weather conditions remain likely given the presence of dry fuels. ..Squitieri.. 11/01/2024 .PREV DISCUSSION... /ISSUED 0158 AM CDT Fri Nov 01 2024/ ...Synopsis... On the backside of a midlevel trough tracking east-northeastward across the Northeast, deep tropospheric drying will occur across portions of the Mid-Atlantic behind a related cold front. A tight pressure gradient and enhanced low-level flow will yield 15 mph sustained westerly surface winds (with gusts upwards of 25-30 mph). These winds will overlap 25-35 percent RH behind the front during the afternoon, and given very dry fuels across the region (90th percentile ERCs), a few hours of elevated fire-weather conditions are expected. While there will be some potential for isolated early-day showers along the front, this activity should be too light and/or isolated to have an appreciable impact on the receptive fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1126 AM CDT Fri Nov 01 2024 Valid 011700Z - 021200Z The primary changes made to the Day 1 Fire Weather Outlook Update was to expand Elevated highlights into southern Pennsylvania, and northeast to portions of coastal New England. In these areas ahead of the cold front, clearing skies are leading to rapid boundary-layer mixing and lowering of RH. Sustained surface winds are already reaching 20 mph in spots, with higher gusts, and short-range guidance consensus suggests that RH should drop to 30-35 percent RH by mid-afternoon. As such, Elevated fire weather conditions remain likely given the presence of dry fuels. ..Squitieri.. 11/01/2024 .PREV DISCUSSION... /ISSUED 0158 AM CDT Fri Nov 01 2024/ ...Synopsis... On the backside of a midlevel trough tracking east-northeastward across the Northeast, deep tropospheric drying will occur across portions of the Mid-Atlantic behind a related cold front. A tight pressure gradient and enhanced low-level flow will yield 15 mph sustained westerly surface winds (with gusts upwards of 25-30 mph). These winds will overlap 25-35 percent RH behind the front during the afternoon, and given very dry fuels across the region (90th percentile ERCs), a few hours of elevated fire-weather conditions are expected. While there will be some potential for isolated early-day showers along the front, this activity should be too light and/or isolated to have an appreciable impact on the receptive fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1126 AM CDT Fri Nov 01 2024 Valid 011700Z - 021200Z The primary changes made to the Day 1 Fire Weather Outlook Update was to expand Elevated highlights into southern Pennsylvania, and northeast to portions of coastal New England. In these areas ahead of the cold front, clearing skies are leading to rapid boundary-layer mixing and lowering of RH. Sustained surface winds are already reaching 20 mph in spots, with higher gusts, and short-range guidance consensus suggests that RH should drop to 30-35 percent RH by mid-afternoon. As such, Elevated fire weather conditions remain likely given the presence of dry fuels. ..Squitieri.. 11/01/2024 .PREV DISCUSSION... /ISSUED 0158 AM CDT Fri Nov 01 2024/ ...Synopsis... On the backside of a midlevel trough tracking east-northeastward across the Northeast, deep tropospheric drying will occur across portions of the Mid-Atlantic behind a related cold front. A tight pressure gradient and enhanced low-level flow will yield 15 mph sustained westerly surface winds (with gusts upwards of 25-30 mph). These winds will overlap 25-35 percent RH behind the front during the afternoon, and given very dry fuels across the region (90th percentile ERCs), a few hours of elevated fire-weather conditions are expected. While there will be some potential for isolated early-day showers along the front, this activity should be too light and/or isolated to have an appreciable impact on the receptive fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1126 AM CDT Fri Nov 01 2024 Valid 011700Z - 021200Z The primary changes made to the Day 1 Fire Weather Outlook Update was to expand Elevated highlights into southern Pennsylvania, and northeast to portions of coastal New England. In these areas ahead of the cold front, clearing skies are leading to rapid boundary-layer mixing and lowering of RH. Sustained surface winds are already reaching 20 mph in spots, with higher gusts, and short-range guidance consensus suggests that RH should drop to 30-35 percent RH by mid-afternoon. As such, Elevated fire weather conditions remain likely given the presence of dry fuels. ..Squitieri.. 11/01/2024 .PREV DISCUSSION... /ISSUED 0158 AM CDT Fri Nov 01 2024/ ...Synopsis... On the backside of a midlevel trough tracking east-northeastward across the Northeast, deep tropospheric drying will occur across portions of the Mid-Atlantic behind a related cold front. A tight pressure gradient and enhanced low-level flow will yield 15 mph sustained westerly surface winds (with gusts upwards of 25-30 mph). These winds will overlap 25-35 percent RH behind the front during the afternoon, and given very dry fuels across the region (90th percentile ERCs), a few hours of elevated fire-weather conditions are expected. While there will be some potential for isolated early-day showers along the front, this activity should be too light and/or isolated to have an appreciable impact on the receptive fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1126 AM CDT Fri Nov 01 2024 Valid 011700Z - 021200Z The primary changes made to the Day 1 Fire Weather Outlook Update was to expand Elevated highlights into southern Pennsylvania, and northeast to portions of coastal New England. In these areas ahead of the cold front, clearing skies are leading to rapid boundary-layer mixing and lowering of RH. Sustained surface winds are already reaching 20 mph in spots, with higher gusts, and short-range guidance consensus suggests that RH should drop to 30-35 percent RH by mid-afternoon. As such, Elevated fire weather conditions remain likely given the presence of dry fuels. ..Squitieri.. 11/01/2024 .PREV DISCUSSION... /ISSUED 0158 AM CDT Fri Nov 01 2024/ ...Synopsis... On the backside of a midlevel trough tracking east-northeastward across the Northeast, deep tropospheric drying will occur across portions of the Mid-Atlantic behind a related cold front. A tight pressure gradient and enhanced low-level flow will yield 15 mph sustained westerly surface winds (with gusts upwards of 25-30 mph). These winds will overlap 25-35 percent RH behind the front during the afternoon, and given very dry fuels across the region (90th percentile ERCs), a few hours of elevated fire-weather conditions are expected. While there will be some potential for isolated early-day showers along the front, this activity should be too light and/or isolated to have an appreciable impact on the receptive fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1126 AM CDT Fri Nov 01 2024 Valid 011700Z - 021200Z The primary changes made to the Day 1 Fire Weather Outlook Update was to expand Elevated highlights into southern Pennsylvania, and northeast to portions of coastal New England. In these areas ahead of the cold front, clearing skies are leading to rapid boundary-layer mixing and lowering of RH. Sustained surface winds are already reaching 20 mph in spots, with higher gusts, and short-range guidance consensus suggests that RH should drop to 30-35 percent RH by mid-afternoon. As such, Elevated fire weather conditions remain likely given the presence of dry fuels. ..Squitieri.. 11/01/2024 .PREV DISCUSSION... /ISSUED 0158 AM CDT Fri Nov 01 2024/ ...Synopsis... On the backside of a midlevel trough tracking east-northeastward across the Northeast, deep tropospheric drying will occur across portions of the Mid-Atlantic behind a related cold front. A tight pressure gradient and enhanced low-level flow will yield 15 mph sustained westerly surface winds (with gusts upwards of 25-30 mph). These winds will overlap 25-35 percent RH behind the front during the afternoon, and given very dry fuels across the region (90th percentile ERCs), a few hours of elevated fire-weather conditions are expected. While there will be some potential for isolated early-day showers along the front, this activity should be too light and/or isolated to have an appreciable impact on the receptive fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1126 AM CDT Fri Nov 01 2024 Valid 011700Z - 021200Z The primary changes made to the Day 1 Fire Weather Outlook Update was to expand Elevated highlights into southern Pennsylvania, and northeast to portions of coastal New England. In these areas ahead of the cold front, clearing skies are leading to rapid boundary-layer mixing and lowering of RH. Sustained surface winds are already reaching 20 mph in spots, with higher gusts, and short-range guidance consensus suggests that RH should drop to 30-35 percent RH by mid-afternoon. As such, Elevated fire weather conditions remain likely given the presence of dry fuels. ..Squitieri.. 11/01/2024 .PREV DISCUSSION... /ISSUED 0158 AM CDT Fri Nov 01 2024/ ...Synopsis... On the backside of a midlevel trough tracking east-northeastward across the Northeast, deep tropospheric drying will occur across portions of the Mid-Atlantic behind a related cold front. A tight pressure gradient and enhanced low-level flow will yield 15 mph sustained westerly surface winds (with gusts upwards of 25-30 mph). These winds will overlap 25-35 percent RH behind the front during the afternoon, and given very dry fuels across the region (90th percentile ERCs), a few hours of elevated fire-weather conditions are expected. While there will be some potential for isolated early-day showers along the front, this activity should be too light and/or isolated to have an appreciable impact on the receptive fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1117 AM CDT Fri Nov 01 2024 Valid 011630Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHERN HIGH PLAINS... ...SUMMARY... Isolated severe hail and/or gusts are possible across parts of the southern High Plains, from this evening into the overnight. ...Southern High Plains... Visible-satellite imagery late this morning shows patches of stratocumulus over the Pecos River Valley. This low-level moisture coincides with the northwesterly fringe of richer moisture located over the Hill Country and Deep South TX. The timelapse of water-vapor imagery shows the onset of an amplifying large-scale trough over the West. A lead lower-latitude disturbance over northern Baja and Sonora will shift eastward along the Mexican border during the period and aid in the development of a lee trough over the southern High Plains beneath moderately strong southwesterly mid-level flow. A gradual intensification of low-level warm-air advection downstream of the upper trough will occur through tonight across the southern High Plains. Model guidance continues to indicate widely spaced/isolated thunderstorms will develop late this afternoon and into the evening across Far West TX into southeastern NM as 500-1000 J/kg MLCAPE develops coincident with the increase in low-level moisture. Thunderstorm coverage should increase from late this evening through the overnight hours, and begin training within a southwest/northeast-oriented plume from far west TX to southern KS. This convective growth will be related to strengthening low-level theta-e and moisture, WAA-related large-scale ascent, and weakening MUCINH. The most intense cells embedded in this regime may produce severe hail or gusts, but the overall areal severe threat still appears to be on the marginal side, due to lack of greater instability/buoyancy. ..Smith/Moore.. 11/01/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1117 AM CDT Fri Nov 01 2024 Valid 011630Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHERN HIGH PLAINS... ...SUMMARY... Isolated severe hail and/or gusts are possible across parts of the southern High Plains, from this evening into the overnight. ...Southern High Plains... Visible-satellite imagery late this morning shows patches of stratocumulus over the Pecos River Valley. This low-level moisture coincides with the northwesterly fringe of richer moisture located over the Hill Country and Deep South TX. The timelapse of water-vapor imagery shows the onset of an amplifying large-scale trough over the West. A lead lower-latitude disturbance over northern Baja and Sonora will shift eastward along the Mexican border during the period and aid in the development of a lee trough over the southern High Plains beneath moderately strong southwesterly mid-level flow. A gradual intensification of low-level warm-air advection downstream of the upper trough will occur through tonight across the southern High Plains. Model guidance continues to indicate widely spaced/isolated thunderstorms will develop late this afternoon and into the evening across Far West TX into southeastern NM as 500-1000 J/kg MLCAPE develops coincident with the increase in low-level moisture. Thunderstorm coverage should increase from late this evening through the overnight hours, and begin training within a southwest/northeast-oriented plume from far west TX to southern KS. This convective growth will be related to strengthening low-level theta-e and moisture, WAA-related large-scale ascent, and weakening MUCINH. The most intense cells embedded in this regime may produce severe hail or gusts, but the overall areal severe threat still appears to be on the marginal side, due to lack of greater instability/buoyancy. ..Smith/Moore.. 11/01/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1117 AM CDT Fri Nov 01 2024 Valid 011630Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHERN HIGH PLAINS... ...SUMMARY... Isolated severe hail and/or gusts are possible across parts of the southern High Plains, from this evening into the overnight. ...Southern High Plains... Visible-satellite imagery late this morning shows patches of stratocumulus over the Pecos River Valley. This low-level moisture coincides with the northwesterly fringe of richer moisture located over the Hill Country and Deep South TX. The timelapse of water-vapor imagery shows the onset of an amplifying large-scale trough over the West. A lead lower-latitude disturbance over northern Baja and Sonora will shift eastward along the Mexican border during the period and aid in the development of a lee trough over the southern High Plains beneath moderately strong southwesterly mid-level flow. A gradual intensification of low-level warm-air advection downstream of the upper trough will occur through tonight across the southern High Plains. Model guidance continues to indicate widely spaced/isolated thunderstorms will develop late this afternoon and into the evening across Far West TX into southeastern NM as 500-1000 J/kg MLCAPE develops coincident with the increase in low-level moisture. Thunderstorm coverage should increase from late this evening through the overnight hours, and begin training within a southwest/northeast-oriented plume from far west TX to southern KS. This convective growth will be related to strengthening low-level theta-e and moisture, WAA-related large-scale ascent, and weakening MUCINH. The most intense cells embedded in this regime may produce severe hail or gusts, but the overall areal severe threat still appears to be on the marginal side, due to lack of greater instability/buoyancy. ..Smith/Moore.. 11/01/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1117 AM CDT Fri Nov 01 2024 Valid 011630Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHERN HIGH PLAINS... ...SUMMARY... Isolated severe hail and/or gusts are possible across parts of the southern High Plains, from this evening into the overnight. ...Southern High Plains... Visible-satellite imagery late this morning shows patches of stratocumulus over the Pecos River Valley. This low-level moisture coincides with the northwesterly fringe of richer moisture located over the Hill Country and Deep South TX. The timelapse of water-vapor imagery shows the onset of an amplifying large-scale trough over the West. A lead lower-latitude disturbance over northern Baja and Sonora will shift eastward along the Mexican border during the period and aid in the development of a lee trough over the southern High Plains beneath moderately strong southwesterly mid-level flow. A gradual intensification of low-level warm-air advection downstream of the upper trough will occur through tonight across the southern High Plains. Model guidance continues to indicate widely spaced/isolated thunderstorms will develop late this afternoon and into the evening across Far West TX into southeastern NM as 500-1000 J/kg MLCAPE develops coincident with the increase in low-level moisture. Thunderstorm coverage should increase from late this evening through the overnight hours, and begin training within a southwest/northeast-oriented plume from far west TX to southern KS. This convective growth will be related to strengthening low-level theta-e and moisture, WAA-related large-scale ascent, and weakening MUCINH. The most intense cells embedded in this regime may produce severe hail or gusts, but the overall areal severe threat still appears to be on the marginal side, due to lack of greater instability/buoyancy. ..Smith/Moore.. 11/01/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1117 AM CDT Fri Nov 01 2024 Valid 011630Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHERN HIGH PLAINS... ...SUMMARY... Isolated severe hail and/or gusts are possible across parts of the southern High Plains, from this evening into the overnight. ...Southern High Plains... Visible-satellite imagery late this morning shows patches of stratocumulus over the Pecos River Valley. This low-level moisture coincides with the northwesterly fringe of richer moisture located over the Hill Country and Deep South TX. The timelapse of water-vapor imagery shows the onset of an amplifying large-scale trough over the West. A lead lower-latitude disturbance over northern Baja and Sonora will shift eastward along the Mexican border during the period and aid in the development of a lee trough over the southern High Plains beneath moderately strong southwesterly mid-level flow. A gradual intensification of low-level warm-air advection downstream of the upper trough will occur through tonight across the southern High Plains. Model guidance continues to indicate widely spaced/isolated thunderstorms will develop late this afternoon and into the evening across Far West TX into southeastern NM as 500-1000 J/kg MLCAPE develops coincident with the increase in low-level moisture. Thunderstorm coverage should increase from late this evening through the overnight hours, and begin training within a southwest/northeast-oriented plume from far west TX to southern KS. This convective growth will be related to strengthening low-level theta-e and moisture, WAA-related large-scale ascent, and weakening MUCINH. The most intense cells embedded in this regime may produce severe hail or gusts, but the overall areal severe threat still appears to be on the marginal side, due to lack of greater instability/buoyancy. ..Smith/Moore.. 11/01/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1117 AM CDT Fri Nov 01 2024 Valid 011630Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHERN HIGH PLAINS... ...SUMMARY... Isolated severe hail and/or gusts are possible across parts of the southern High Plains, from this evening into the overnight. ...Southern High Plains... Visible-satellite imagery late this morning shows patches of stratocumulus over the Pecos River Valley. This low-level moisture coincides with the northwesterly fringe of richer moisture located over the Hill Country and Deep South TX. The timelapse of water-vapor imagery shows the onset of an amplifying large-scale trough over the West. A lead lower-latitude disturbance over northern Baja and Sonora will shift eastward along the Mexican border during the period and aid in the development of a lee trough over the southern High Plains beneath moderately strong southwesterly mid-level flow. A gradual intensification of low-level warm-air advection downstream of the upper trough will occur through tonight across the southern High Plains. Model guidance continues to indicate widely spaced/isolated thunderstorms will develop late this afternoon and into the evening across Far West TX into southeastern NM as 500-1000 J/kg MLCAPE develops coincident with the increase in low-level moisture. Thunderstorm coverage should increase from late this evening through the overnight hours, and begin training within a southwest/northeast-oriented plume from far west TX to southern KS. This convective growth will be related to strengthening low-level theta-e and moisture, WAA-related large-scale ascent, and weakening MUCINH. The most intense cells embedded in this regime may produce severe hail or gusts, but the overall areal severe threat still appears to be on the marginal side, due to lack of greater instability/buoyancy. ..Smith/Moore.. 11/01/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1117 AM CDT Fri Nov 01 2024 Valid 011630Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHERN HIGH PLAINS... ...SUMMARY... Isolated severe hail and/or gusts are possible across parts of the southern High Plains, from this evening into the overnight. ...Southern High Plains... Visible-satellite imagery late this morning shows patches of stratocumulus over the Pecos River Valley. This low-level moisture coincides with the northwesterly fringe of richer moisture located over the Hill Country and Deep South TX. The timelapse of water-vapor imagery shows the onset of an amplifying large-scale trough over the West. A lead lower-latitude disturbance over northern Baja and Sonora will shift eastward along the Mexican border during the period and aid in the development of a lee trough over the southern High Plains beneath moderately strong southwesterly mid-level flow. A gradual intensification of low-level warm-air advection downstream of the upper trough will occur through tonight across the southern High Plains. Model guidance continues to indicate widely spaced/isolated thunderstorms will develop late this afternoon and into the evening across Far West TX into southeastern NM as 500-1000 J/kg MLCAPE develops coincident with the increase in low-level moisture. Thunderstorm coverage should increase from late this evening through the overnight hours, and begin training within a southwest/northeast-oriented plume from far west TX to southern KS. This convective growth will be related to strengthening low-level theta-e and moisture, WAA-related large-scale ascent, and weakening MUCINH. The most intense cells embedded in this regime may produce severe hail or gusts, but the overall areal severe threat still appears to be on the marginal side, due to lack of greater instability/buoyancy. ..Smith/Moore.. 11/01/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0754 AM CDT Fri Nov 01 2024 Valid 011300Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHERN HIGH PLAINS... ...SUMMARY... Isolated severe hail and/or gusts are possible across parts of the southern High Plains, from this evening into the overnight. ...Synopsis... Today will mark the start of a substantial mid/upper-level pattern amplification over the CONUS. This will be mainly related to a strong shortwave trough now digging southeastward over the Pacific, offshore from OR, and south of a cyclone now covering the BC Coast and adjacent waters. The cyclone will move inland and devolve to an open-wave trough, but also, will phase better with the amplifying shortwave trough. By the end of the period, this should result in a major synoptic-scale trough from southern BC over the Pacific Coast States and offshore from Baja. Associated cyclonic flow then will cover nearly all the CONUS from the High Plains westward, with height falls from the northern/central Rockies to the southern High Plains. At the surface, 11Z analysis showed a low over southern QC, with a cold front southwestward across western portions of NY/PA/WV, eastern KY, middle TN, northern MS, to east and south-central parts of TX. The western part of this frontal zone will decelerate today, become more diffuse, and merge with an inland-shifting, older, marine/warm frontal zone now lying quasistationary near the LA coastline and over deep south TX. The latter boundary will demarcate the northern extent of optimal Gulf moisture, and should shift northward/inland through tonight, but remain southeast of west TX and eastern NM until day 2. Another low, with a weak cold front arching southward over the central High Plains, will dissipate through the period, as lee troughing intensifies just to the west (in advance of the strengthening mid/upper trough). ...Southern High Plains... Isolated to widely scattered thunderstorms are expected to form over portions of far west TX and southeastern NM from late afternoon into evening, as gradually increasing boundary-layer moisture becomes available to diurnally heated higher terrain in the region. Thunderstorm coverage should increase from late this evening through the overnight hours, and begin training within a southwest/ northeast-oriented plume from far west TX to southern KS. This convective growth will be related to strengthening low-level theta-e and moisture, WAA-related large-scale ascent, and weakening MUCINH. The most intense cells embedded in this regime may produce severe hail or gusts, but the overall areal severe threat still appears to be on the marginal side, due to lack of greater instability/buoyancy. In response to trough amplification aloft over the West, low-level warm advection and moisture transport will persist and enlarge into the southern High Plains region, with a 30-40-kt LLJ progged to develop overnight. However this will be an early stage of the return-flow process under modest lapse rates aloft, with considerable residual continental trajectories still involved in low levels, and the most-favorable, Gulf-modified parcels not forecast to reach the region until day-2 and beyond. Though upper 50s to low 60 F surface dewpoints should spread into the Permian Basin region of west TX and southeastern NM tonight, the area of strongest lift farther northwest will have less moisture. MUCAPE of 500-800 J/kg is expected around the time of most of the convective development, increasing to the 1000-1500 J/kg range in non-convective inflow sector by the end of the period. A layer of weaker midlevel flow above the LLJ will restrict vertical shear, keeping effective-shear magnitudes under 30 kt over most of the area. As such, any supercell processes should be isolated and transient in character, especially considering the anticipated upscale evolution to a relatively dense convective-precip corridor. ...TX Rio Grande Valley between DRT-LRD... Widely scattered to scattered thunderstorms should develop this afternoon as the easterly/upslope component of flow impinges on higher terrain of the Serranias del Burro of northern Coahuila, and adjoining higher slopes in the direction of the Rio Grande. Isolated large hail and damaging gusts are possible, but predominantly on the Mexican side of the border. The boundary layer in the valley will be strongly heated and richly moist, with dewpoints from the upper 60s to low 70s F. Given the lack of stronger midlevel flow, however, two related factors render a highly conditional potential on the TX side: 1. Modest deep shear, despite strong veering with height from surface into midlevels. Forecast soundings suggest just 30-35-kt effective-shear magnitudes. 2. Uncertainty about whether orographically initiated convection can remain organized/severe long enough to reach the border. Early-stage supercells, if any, may not survive far enough eastward in that mode, but outflow-dominant/forward-propagating multicellular clusters might. As such, a very conditional severe-gust threat may reach TX. Given the absence of a robust EML and of related MLCINH, deep convection also may develop in the warm sector east of the Rio Grande, amid strong diurnal heating and rich moisture, but the foci for lift are quite unclear at this time. With all these uncertainties, will refrain from an unconditional severe area for this outlook cycle. ..Edwards/Mosier.. 11/01/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0754 AM CDT Fri Nov 01 2024 Valid 011300Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHERN HIGH PLAINS... ...SUMMARY... Isolated severe hail and/or gusts are possible across parts of the southern High Plains, from this evening into the overnight. ...Synopsis... Today will mark the start of a substantial mid/upper-level pattern amplification over the CONUS. This will be mainly related to a strong shortwave trough now digging southeastward over the Pacific, offshore from OR, and south of a cyclone now covering the BC Coast and adjacent waters. The cyclone will move inland and devolve to an open-wave trough, but also, will phase better with the amplifying shortwave trough. By the end of the period, this should result in a major synoptic-scale trough from southern BC over the Pacific Coast States and offshore from Baja. Associated cyclonic flow then will cover nearly all the CONUS from the High Plains westward, with height falls from the northern/central Rockies to the southern High Plains. At the surface, 11Z analysis showed a low over southern QC, with a cold front southwestward across western portions of NY/PA/WV, eastern KY, middle TN, northern MS, to east and south-central parts of TX. The western part of this frontal zone will decelerate today, become more diffuse, and merge with an inland-shifting, older, marine/warm frontal zone now lying quasistationary near the LA coastline and over deep south TX. The latter boundary will demarcate the northern extent of optimal Gulf moisture, and should shift northward/inland through tonight, but remain southeast of west TX and eastern NM until day 2. Another low, with a weak cold front arching southward over the central High Plains, will dissipate through the period, as lee troughing intensifies just to the west (in advance of the strengthening mid/upper trough). ...Southern High Plains... Isolated to widely scattered thunderstorms are expected to form over portions of far west TX and southeastern NM from late afternoon into evening, as gradually increasing boundary-layer moisture becomes available to diurnally heated higher terrain in the region. Thunderstorm coverage should increase from late this evening through the overnight hours, and begin training within a southwest/ northeast-oriented plume from far west TX to southern KS. This convective growth will be related to strengthening low-level theta-e and moisture, WAA-related large-scale ascent, and weakening MUCINH. The most intense cells embedded in this regime may produce severe hail or gusts, but the overall areal severe threat still appears to be on the marginal side, due to lack of greater instability/buoyancy. In response to trough amplification aloft over the West, low-level warm advection and moisture transport will persist and enlarge into the southern High Plains region, with a 30-40-kt LLJ progged to develop overnight. However this will be an early stage of the return-flow process under modest lapse rates aloft, with considerable residual continental trajectories still involved in low levels, and the most-favorable, Gulf-modified parcels not forecast to reach the region until day-2 and beyond. Though upper 50s to low 60 F surface dewpoints should spread into the Permian Basin region of west TX and southeastern NM tonight, the area of strongest lift farther northwest will have less moisture. MUCAPE of 500-800 J/kg is expected around the time of most of the convective development, increasing to the 1000-1500 J/kg range in non-convective inflow sector by the end of the period. A layer of weaker midlevel flow above the LLJ will restrict vertical shear, keeping effective-shear magnitudes under 30 kt over most of the area. As such, any supercell processes should be isolated and transient in character, especially considering the anticipated upscale evolution to a relatively dense convective-precip corridor. ...TX Rio Grande Valley between DRT-LRD... Widely scattered to scattered thunderstorms should develop this afternoon as the easterly/upslope component of flow impinges on higher terrain of the Serranias del Burro of northern Coahuila, and adjoining higher slopes in the direction of the Rio Grande. Isolated large hail and damaging gusts are possible, but predominantly on the Mexican side of the border. The boundary layer in the valley will be strongly heated and richly moist, with dewpoints from the upper 60s to low 70s F. Given the lack of stronger midlevel flow, however, two related factors render a highly conditional potential on the TX side: 1. Modest deep shear, despite strong veering with height from surface into midlevels. Forecast soundings suggest just 30-35-kt effective-shear magnitudes. 2. Uncertainty about whether orographically initiated convection can remain organized/severe long enough to reach the border. Early-stage supercells, if any, may not survive far enough eastward in that mode, but outflow-dominant/forward-propagating multicellular clusters might. As such, a very conditional severe-gust threat may reach TX. Given the absence of a robust EML and of related MLCINH, deep convection also may develop in the warm sector east of the Rio Grande, amid strong diurnal heating and rich moisture, but the foci for lift are quite unclear at this time. With all these uncertainties, will refrain from an unconditional severe area for this outlook cycle. ..Edwards/Mosier.. 11/01/2024 Read more