Aggregator

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 AM CST Tue Nov 12 2024 Valid 131200Z - 141200Z ...Synopsis... Gusty post-frontal off-shore flow will continue across portions of the Northeast from far eastern PA and southern NJ extending northeast through southern New England. A very dry air mass will remain in place with relative humidity reductions to around 30-35 percent likely. Given the drought conditions and receptive fuels in this region, an Elevated delineation was maintained with this outlook. Locally Critical conditions may be possible, though the limited spatial extent of this threat precludes the need to include a Critical area at this time. ..Thornton.. 11/12/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 AM CST Tue Nov 12 2024 Valid 131200Z - 141200Z ...Synopsis... Gusty post-frontal off-shore flow will continue across portions of the Northeast from far eastern PA and southern NJ extending northeast through southern New England. A very dry air mass will remain in place with relative humidity reductions to around 30-35 percent likely. Given the drought conditions and receptive fuels in this region, an Elevated delineation was maintained with this outlook. Locally Critical conditions may be possible, though the limited spatial extent of this threat precludes the need to include a Critical area at this time. ..Thornton.. 11/12/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 AM CST Tue Nov 12 2024 Valid 131200Z - 141200Z ...Synopsis... Gusty post-frontal off-shore flow will continue across portions of the Northeast from far eastern PA and southern NJ extending northeast through southern New England. A very dry air mass will remain in place with relative humidity reductions to around 30-35 percent likely. Given the drought conditions and receptive fuels in this region, an Elevated delineation was maintained with this outlook. Locally Critical conditions may be possible, though the limited spatial extent of this threat precludes the need to include a Critical area at this time. ..Thornton.. 11/12/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0158 AM CST Tue Nov 12 2024 Valid 121200Z - 131200Z ...Synopsis... ...Southern California... A weak cold front will move across southern California through the morning. Behind this frontal passage, gusty northwest winds will be enhanced near favored downslope terrain features across Santa Barbra and Ventura Counties. Relative humidity will hover around elevated thresholds. Relative humidity will decrease, especially at mid/upper slopes, below critical relative humidity thresholds with poor overnight recovery tonight into D2/Wednesday morning. However, winds are expected to weaken below thresholds during this period. An Elevated delineation was maintained with this outlook. ...New England... Gusty northwesterly flow will overlap relative humidity reductions to 35-40 percent across New England this afternoon. Though relative humidity will be marginal, recent fire activity has shown fuels in this region are receptive to fire spread with drought conditions and very little recent rainfall. An Elevated delineation was included to cover this threat, given the potential for strong and gusty winds. ..Thornton.. 11/12/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0158 AM CST Tue Nov 12 2024 Valid 121200Z - 131200Z ...Synopsis... ...Southern California... A weak cold front will move across southern California through the morning. Behind this frontal passage, gusty northwest winds will be enhanced near favored downslope terrain features across Santa Barbra and Ventura Counties. Relative humidity will hover around elevated thresholds. Relative humidity will decrease, especially at mid/upper slopes, below critical relative humidity thresholds with poor overnight recovery tonight into D2/Wednesday morning. However, winds are expected to weaken below thresholds during this period. An Elevated delineation was maintained with this outlook. ...New England... Gusty northwesterly flow will overlap relative humidity reductions to 35-40 percent across New England this afternoon. Though relative humidity will be marginal, recent fire activity has shown fuels in this region are receptive to fire spread with drought conditions and very little recent rainfall. An Elevated delineation was included to cover this threat, given the potential for strong and gusty winds. ..Thornton.. 11/12/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0158 AM CST Tue Nov 12 2024 Valid 121200Z - 131200Z ...Synopsis... ...Southern California... A weak cold front will move across southern California through the morning. Behind this frontal passage, gusty northwest winds will be enhanced near favored downslope terrain features across Santa Barbra and Ventura Counties. Relative humidity will hover around elevated thresholds. Relative humidity will decrease, especially at mid/upper slopes, below critical relative humidity thresholds with poor overnight recovery tonight into D2/Wednesday morning. However, winds are expected to weaken below thresholds during this period. An Elevated delineation was maintained with this outlook. ...New England... Gusty northwesterly flow will overlap relative humidity reductions to 35-40 percent across New England this afternoon. Though relative humidity will be marginal, recent fire activity has shown fuels in this region are receptive to fire spread with drought conditions and very little recent rainfall. An Elevated delineation was included to cover this threat, given the potential for strong and gusty winds. ..Thornton.. 11/12/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0158 AM CST Tue Nov 12 2024 Valid 121200Z - 131200Z ...Synopsis... ...Southern California... A weak cold front will move across southern California through the morning. Behind this frontal passage, gusty northwest winds will be enhanced near favored downslope terrain features across Santa Barbra and Ventura Counties. Relative humidity will hover around elevated thresholds. Relative humidity will decrease, especially at mid/upper slopes, below critical relative humidity thresholds with poor overnight recovery tonight into D2/Wednesday morning. However, winds are expected to weaken below thresholds during this period. An Elevated delineation was maintained with this outlook. ...New England... Gusty northwesterly flow will overlap relative humidity reductions to 35-40 percent across New England this afternoon. Though relative humidity will be marginal, recent fire activity has shown fuels in this region are receptive to fire spread with drought conditions and very little recent rainfall. An Elevated delineation was included to cover this threat, given the potential for strong and gusty winds. ..Thornton.. 11/12/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0158 AM CST Tue Nov 12 2024 Valid 121200Z - 131200Z ...Synopsis... ...Southern California... A weak cold front will move across southern California through the morning. Behind this frontal passage, gusty northwest winds will be enhanced near favored downslope terrain features across Santa Barbra and Ventura Counties. Relative humidity will hover around elevated thresholds. Relative humidity will decrease, especially at mid/upper slopes, below critical relative humidity thresholds with poor overnight recovery tonight into D2/Wednesday morning. However, winds are expected to weaken below thresholds during this period. An Elevated delineation was maintained with this outlook. ...New England... Gusty northwesterly flow will overlap relative humidity reductions to 35-40 percent across New England this afternoon. Though relative humidity will be marginal, recent fire activity has shown fuels in this region are receptive to fire spread with drought conditions and very little recent rainfall. An Elevated delineation was included to cover this threat, given the potential for strong and gusty winds. ..Thornton.. 11/12/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1257 AM CST Tue Nov 12 2024 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE LOWER MS VALLEY AND NORTHEAST GULF COAST...FOR COASTAL WA/OR/NORTHERN CA... ...SUMMARY... A marginal tornado/wind threat is apparent on Wednesday afternoon into Wednesday night across a part of the central Gulf Coast States. Thunderstorms with strong to locally severe gusts are also possible near the immediate coasts of Washington, Oregon, and northern California. ...Synopsis... A mid/upper-level shortwave trough is forecast to move eastward from the Great Plains toward the Midwest and OH/TN Valleys on Wednesday. In conjunction with this shortwave trough, a weak surface low will move from the east-central Plains toward the Great Lakes region, as a trailing cold front moves through parts of the middle/lower MS Valley. Farther west, a deep mid/upper-level trough will progress farther inland across the western CONUS, as an embedded shortwave moves across northern CA into the interior Northwest. ...Lower Mississippi Valley/Central Gulf Coast region... Rich low-level moisture (with upper 60s to lower 70s F dewpoints) is forecast to gradually spread northward across the lower MS Valley region from later in the D1/Tuesday period into D2/Wednesday. Weak lapse rates will tend to limit instability, while stronger mid/upper-level flow will generally remain north of the richer moisture. However, deep-layer shear will likely become at least marginally supportive of organized storms, while some enhancement to low-level flow/shear is forecast as the shortwave trough to the north glances the region. This evolution could support a few marginal supercells and/or stronger clusters during the afternoon and evening, with a threat of locally damaging winds and possibly a tornado or two. Elevated storms will also be possible through the day/evening to the north of the richer surface moisture. While effective shear will be sufficient for a few strong elevated storms, the severe potential with northward extent will tend to be limited by weak midlevel lapse rates and generally marginal MUCAPE. ...WA/OR/northern CA coasts... Cooling temperatures aloft will support weak destabilization in the vicinity of the WA/OR/northern CA coasts through the day on Wednesday. While convection will be rather low-topped, instability may become sufficient (with SBCAPE potentially in the 200-500 J/kg range) for occasional thunderstorms. The strongest low-level flow will precede the primary destabilization, but persistent and rather strong deep-layer southwesterly flow could support modestly organized line segments and/or weakly rotating cells, with a threat of isolated severe convective gusts and perhaps some small hail. A brief tornado also cannot be ruled out, though the favored location (if any) of any longer-lived rotating cells remains uncertain at this time. ..Dean.. 11/12/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1257 AM CST Tue Nov 12 2024 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE LOWER MS VALLEY AND NORTHEAST GULF COAST...FOR COASTAL WA/OR/NORTHERN CA... ...SUMMARY... A marginal tornado/wind threat is apparent on Wednesday afternoon into Wednesday night across a part of the central Gulf Coast States. Thunderstorms with strong to locally severe gusts are also possible near the immediate coasts of Washington, Oregon, and northern California. ...Synopsis... A mid/upper-level shortwave trough is forecast to move eastward from the Great Plains toward the Midwest and OH/TN Valleys on Wednesday. In conjunction with this shortwave trough, a weak surface low will move from the east-central Plains toward the Great Lakes region, as a trailing cold front moves through parts of the middle/lower MS Valley. Farther west, a deep mid/upper-level trough will progress farther inland across the western CONUS, as an embedded shortwave moves across northern CA into the interior Northwest. ...Lower Mississippi Valley/Central Gulf Coast region... Rich low-level moisture (with upper 60s to lower 70s F dewpoints) is forecast to gradually spread northward across the lower MS Valley region from later in the D1/Tuesday period into D2/Wednesday. Weak lapse rates will tend to limit instability, while stronger mid/upper-level flow will generally remain north of the richer moisture. However, deep-layer shear will likely become at least marginally supportive of organized storms, while some enhancement to low-level flow/shear is forecast as the shortwave trough to the north glances the region. This evolution could support a few marginal supercells and/or stronger clusters during the afternoon and evening, with a threat of locally damaging winds and possibly a tornado or two. Elevated storms will also be possible through the day/evening to the north of the richer surface moisture. While effective shear will be sufficient for a few strong elevated storms, the severe potential with northward extent will tend to be limited by weak midlevel lapse rates and generally marginal MUCAPE. ...WA/OR/northern CA coasts... Cooling temperatures aloft will support weak destabilization in the vicinity of the WA/OR/northern CA coasts through the day on Wednesday. While convection will be rather low-topped, instability may become sufficient (with SBCAPE potentially in the 200-500 J/kg range) for occasional thunderstorms. The strongest low-level flow will precede the primary destabilization, but persistent and rather strong deep-layer southwesterly flow could support modestly organized line segments and/or weakly rotating cells, with a threat of isolated severe convective gusts and perhaps some small hail. A brief tornado also cannot be ruled out, though the favored location (if any) of any longer-lived rotating cells remains uncertain at this time. ..Dean.. 11/12/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1257 AM CST Tue Nov 12 2024 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE LOWER MS VALLEY AND NORTHEAST GULF COAST...FOR COASTAL WA/OR/NORTHERN CA... ...SUMMARY... A marginal tornado/wind threat is apparent on Wednesday afternoon into Wednesday night across a part of the central Gulf Coast States. Thunderstorms with strong to locally severe gusts are also possible near the immediate coasts of Washington, Oregon, and northern California. ...Synopsis... A mid/upper-level shortwave trough is forecast to move eastward from the Great Plains toward the Midwest and OH/TN Valleys on Wednesday. In conjunction with this shortwave trough, a weak surface low will move from the east-central Plains toward the Great Lakes region, as a trailing cold front moves through parts of the middle/lower MS Valley. Farther west, a deep mid/upper-level trough will progress farther inland across the western CONUS, as an embedded shortwave moves across northern CA into the interior Northwest. ...Lower Mississippi Valley/Central Gulf Coast region... Rich low-level moisture (with upper 60s to lower 70s F dewpoints) is forecast to gradually spread northward across the lower MS Valley region from later in the D1/Tuesday period into D2/Wednesday. Weak lapse rates will tend to limit instability, while stronger mid/upper-level flow will generally remain north of the richer moisture. However, deep-layer shear will likely become at least marginally supportive of organized storms, while some enhancement to low-level flow/shear is forecast as the shortwave trough to the north glances the region. This evolution could support a few marginal supercells and/or stronger clusters during the afternoon and evening, with a threat of locally damaging winds and possibly a tornado or two. Elevated storms will also be possible through the day/evening to the north of the richer surface moisture. While effective shear will be sufficient for a few strong elevated storms, the severe potential with northward extent will tend to be limited by weak midlevel lapse rates and generally marginal MUCAPE. ...WA/OR/northern CA coasts... Cooling temperatures aloft will support weak destabilization in the vicinity of the WA/OR/northern CA coasts through the day on Wednesday. While convection will be rather low-topped, instability may become sufficient (with SBCAPE potentially in the 200-500 J/kg range) for occasional thunderstorms. The strongest low-level flow will precede the primary destabilization, but persistent and rather strong deep-layer southwesterly flow could support modestly organized line segments and/or weakly rotating cells, with a threat of isolated severe convective gusts and perhaps some small hail. A brief tornado also cannot be ruled out, though the favored location (if any) of any longer-lived rotating cells remains uncertain at this time. ..Dean.. 11/12/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1257 AM CST Tue Nov 12 2024 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE LOWER MS VALLEY AND NORTHEAST GULF COAST...FOR COASTAL WA/OR/NORTHERN CA... ...SUMMARY... A marginal tornado/wind threat is apparent on Wednesday afternoon into Wednesday night across a part of the central Gulf Coast States. Thunderstorms with strong to locally severe gusts are also possible near the immediate coasts of Washington, Oregon, and northern California. ...Synopsis... A mid/upper-level shortwave trough is forecast to move eastward from the Great Plains toward the Midwest and OH/TN Valleys on Wednesday. In conjunction with this shortwave trough, a weak surface low will move from the east-central Plains toward the Great Lakes region, as a trailing cold front moves through parts of the middle/lower MS Valley. Farther west, a deep mid/upper-level trough will progress farther inland across the western CONUS, as an embedded shortwave moves across northern CA into the interior Northwest. ...Lower Mississippi Valley/Central Gulf Coast region... Rich low-level moisture (with upper 60s to lower 70s F dewpoints) is forecast to gradually spread northward across the lower MS Valley region from later in the D1/Tuesday period into D2/Wednesday. Weak lapse rates will tend to limit instability, while stronger mid/upper-level flow will generally remain north of the richer moisture. However, deep-layer shear will likely become at least marginally supportive of organized storms, while some enhancement to low-level flow/shear is forecast as the shortwave trough to the north glances the region. This evolution could support a few marginal supercells and/or stronger clusters during the afternoon and evening, with a threat of locally damaging winds and possibly a tornado or two. Elevated storms will also be possible through the day/evening to the north of the richer surface moisture. While effective shear will be sufficient for a few strong elevated storms, the severe potential with northward extent will tend to be limited by weak midlevel lapse rates and generally marginal MUCAPE. ...WA/OR/northern CA coasts... Cooling temperatures aloft will support weak destabilization in the vicinity of the WA/OR/northern CA coasts through the day on Wednesday. While convection will be rather low-topped, instability may become sufficient (with SBCAPE potentially in the 200-500 J/kg range) for occasional thunderstorms. The strongest low-level flow will precede the primary destabilization, but persistent and rather strong deep-layer southwesterly flow could support modestly organized line segments and/or weakly rotating cells, with a threat of isolated severe convective gusts and perhaps some small hail. A brief tornado also cannot be ruled out, though the favored location (if any) of any longer-lived rotating cells remains uncertain at this time. ..Dean.. 11/12/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1257 AM CST Tue Nov 12 2024 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE LOWER MS VALLEY AND NORTHEAST GULF COAST...FOR COASTAL WA/OR/NORTHERN CA... ...SUMMARY... A marginal tornado/wind threat is apparent on Wednesday afternoon into Wednesday night across a part of the central Gulf Coast States. Thunderstorms with strong to locally severe gusts are also possible near the immediate coasts of Washington, Oregon, and northern California. ...Synopsis... A mid/upper-level shortwave trough is forecast to move eastward from the Great Plains toward the Midwest and OH/TN Valleys on Wednesday. In conjunction with this shortwave trough, a weak surface low will move from the east-central Plains toward the Great Lakes region, as a trailing cold front moves through parts of the middle/lower MS Valley. Farther west, a deep mid/upper-level trough will progress farther inland across the western CONUS, as an embedded shortwave moves across northern CA into the interior Northwest. ...Lower Mississippi Valley/Central Gulf Coast region... Rich low-level moisture (with upper 60s to lower 70s F dewpoints) is forecast to gradually spread northward across the lower MS Valley region from later in the D1/Tuesday period into D2/Wednesday. Weak lapse rates will tend to limit instability, while stronger mid/upper-level flow will generally remain north of the richer moisture. However, deep-layer shear will likely become at least marginally supportive of organized storms, while some enhancement to low-level flow/shear is forecast as the shortwave trough to the north glances the region. This evolution could support a few marginal supercells and/or stronger clusters during the afternoon and evening, with a threat of locally damaging winds and possibly a tornado or two. Elevated storms will also be possible through the day/evening to the north of the richer surface moisture. While effective shear will be sufficient for a few strong elevated storms, the severe potential with northward extent will tend to be limited by weak midlevel lapse rates and generally marginal MUCAPE. ...WA/OR/northern CA coasts... Cooling temperatures aloft will support weak destabilization in the vicinity of the WA/OR/northern CA coasts through the day on Wednesday. While convection will be rather low-topped, instability may become sufficient (with SBCAPE potentially in the 200-500 J/kg range) for occasional thunderstorms. The strongest low-level flow will precede the primary destabilization, but persistent and rather strong deep-layer southwesterly flow could support modestly organized line segments and/or weakly rotating cells, with a threat of isolated severe convective gusts and perhaps some small hail. A brief tornado also cannot be ruled out, though the favored location (if any) of any longer-lived rotating cells remains uncertain at this time. ..Dean.. 11/12/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1132 PM CST Mon Nov 11 2024 Valid 121200Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS EVENING ACROSS PARTS OF THE TEXAS SOUTH PLAINS AND PANHANDLE...AND ADJACENT PORTIONS OF WESTERN OKLAHOMA... ...SUMMARY... A couple of strong thunderstorms may impact parts of the Texas South Plains and Panhandle vicinity this evening, perhaps accompanied by some risk for severe weather. ...Synopsis... The westerlies appear likely to remain a bit more progressive across the eastern mid-latitude Pacific into western North America than farther downstream, from near the Atlantic Seaboard through the Atlantic. Within this regime, another significant mid-level trough, with at least a couple of embedded short wave perturbations, is forecast to approach the Pacific coast later today through tonight. As this occurs, a fairly vigorous perturbation within the southern portion of a splitting preceding trough is likely to continue east of the southern Great Basin, across and east of the southern Rockies by daybreak Wednesday. An associated cold front probably will overtake modest lee surface troughing across central and southern portions of the high plains by late tonight. Before it does, boundary-layer moisture return in a narrow plume emanating from the Rio Grande Valley, beneath steepening lower/mid-tropospheric lapse rates, might contribute to a corridor of weak to modest destabilization by late this afternoon across the Texas South Plains into Panhandle vicinity. ...Southern Great Plains... Near the leading edge of a narrow plume of elevated mixed-layer air forecast to advect north-northeastward through southern portions of the high plains, models indicate that differential surface heating may contribute to a strengthening low-level baroclinic zone across parts of the Texas South Plains and Panhandle by late this afternoon. This will probably become a focus for strengthening near-surface warm advection by early this evening, downstream of the short wave impulse progressing across the southern Rockies. This is likely to coincide with increasing low-level moisture return, which might include boundary-layer dew points as high as the lower 60s F near the immediate vicinity of the surface boundary, southward through the Texas South Plains. With regard to potential for severe storm development late this afternoon into tonight, the signal remains muted in the latest high resolution ensemble output and associated machine learning guidance. However, given the potential for at least a narrow corridor of modest boundary-layer destabilization, which may include mixed-layer CAPE on the order of 500-1000 J/kg, large-scale forcing for ascent and strengthening shear appear conducive to organized convective development. There appears a window of opportunity for the evolution of one or two boundary-layer based supercells across parts of the Texas South Plains into Panhandle, before a more general increase in thunderstorm development ensues northeastward across parts of Oklahoma and Kansas later tonight. Rooted within an increasingly elevated warm advected regime, forecast soundings suggest minimal potential for a continuing severe hail threat, once any possible boundary-layer based convective development diminishes. ..Kerr/Thornton.. 11/12/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1132 PM CST Mon Nov 11 2024 Valid 121200Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS EVENING ACROSS PARTS OF THE TEXAS SOUTH PLAINS AND PANHANDLE...AND ADJACENT PORTIONS OF WESTERN OKLAHOMA... ...SUMMARY... A couple of strong thunderstorms may impact parts of the Texas South Plains and Panhandle vicinity this evening, perhaps accompanied by some risk for severe weather. ...Synopsis... The westerlies appear likely to remain a bit more progressive across the eastern mid-latitude Pacific into western North America than farther downstream, from near the Atlantic Seaboard through the Atlantic. Within this regime, another significant mid-level trough, with at least a couple of embedded short wave perturbations, is forecast to approach the Pacific coast later today through tonight. As this occurs, a fairly vigorous perturbation within the southern portion of a splitting preceding trough is likely to continue east of the southern Great Basin, across and east of the southern Rockies by daybreak Wednesday. An associated cold front probably will overtake modest lee surface troughing across central and southern portions of the high plains by late tonight. Before it does, boundary-layer moisture return in a narrow plume emanating from the Rio Grande Valley, beneath steepening lower/mid-tropospheric lapse rates, might contribute to a corridor of weak to modest destabilization by late this afternoon across the Texas South Plains into Panhandle vicinity. ...Southern Great Plains... Near the leading edge of a narrow plume of elevated mixed-layer air forecast to advect north-northeastward through southern portions of the high plains, models indicate that differential surface heating may contribute to a strengthening low-level baroclinic zone across parts of the Texas South Plains and Panhandle by late this afternoon. This will probably become a focus for strengthening near-surface warm advection by early this evening, downstream of the short wave impulse progressing across the southern Rockies. This is likely to coincide with increasing low-level moisture return, which might include boundary-layer dew points as high as the lower 60s F near the immediate vicinity of the surface boundary, southward through the Texas South Plains. With regard to potential for severe storm development late this afternoon into tonight, the signal remains muted in the latest high resolution ensemble output and associated machine learning guidance. However, given the potential for at least a narrow corridor of modest boundary-layer destabilization, which may include mixed-layer CAPE on the order of 500-1000 J/kg, large-scale forcing for ascent and strengthening shear appear conducive to organized convective development. There appears a window of opportunity for the evolution of one or two boundary-layer based supercells across parts of the Texas South Plains into Panhandle, before a more general increase in thunderstorm development ensues northeastward across parts of Oklahoma and Kansas later tonight. Rooted within an increasingly elevated warm advected regime, forecast soundings suggest minimal potential for a continuing severe hail threat, once any possible boundary-layer based convective development diminishes. ..Kerr/Thornton.. 11/12/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1132 PM CST Mon Nov 11 2024 Valid 121200Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS EVENING ACROSS PARTS OF THE TEXAS SOUTH PLAINS AND PANHANDLE...AND ADJACENT PORTIONS OF WESTERN OKLAHOMA... ...SUMMARY... A couple of strong thunderstorms may impact parts of the Texas South Plains and Panhandle vicinity this evening, perhaps accompanied by some risk for severe weather. ...Synopsis... The westerlies appear likely to remain a bit more progressive across the eastern mid-latitude Pacific into western North America than farther downstream, from near the Atlantic Seaboard through the Atlantic. Within this regime, another significant mid-level trough, with at least a couple of embedded short wave perturbations, is forecast to approach the Pacific coast later today through tonight. As this occurs, a fairly vigorous perturbation within the southern portion of a splitting preceding trough is likely to continue east of the southern Great Basin, across and east of the southern Rockies by daybreak Wednesday. An associated cold front probably will overtake modest lee surface troughing across central and southern portions of the high plains by late tonight. Before it does, boundary-layer moisture return in a narrow plume emanating from the Rio Grande Valley, beneath steepening lower/mid-tropospheric lapse rates, might contribute to a corridor of weak to modest destabilization by late this afternoon across the Texas South Plains into Panhandle vicinity. ...Southern Great Plains... Near the leading edge of a narrow plume of elevated mixed-layer air forecast to advect north-northeastward through southern portions of the high plains, models indicate that differential surface heating may contribute to a strengthening low-level baroclinic zone across parts of the Texas South Plains and Panhandle by late this afternoon. This will probably become a focus for strengthening near-surface warm advection by early this evening, downstream of the short wave impulse progressing across the southern Rockies. This is likely to coincide with increasing low-level moisture return, which might include boundary-layer dew points as high as the lower 60s F near the immediate vicinity of the surface boundary, southward through the Texas South Plains. With regard to potential for severe storm development late this afternoon into tonight, the signal remains muted in the latest high resolution ensemble output and associated machine learning guidance. However, given the potential for at least a narrow corridor of modest boundary-layer destabilization, which may include mixed-layer CAPE on the order of 500-1000 J/kg, large-scale forcing for ascent and strengthening shear appear conducive to organized convective development. There appears a window of opportunity for the evolution of one or two boundary-layer based supercells across parts of the Texas South Plains into Panhandle, before a more general increase in thunderstorm development ensues northeastward across parts of Oklahoma and Kansas later tonight. Rooted within an increasingly elevated warm advected regime, forecast soundings suggest minimal potential for a continuing severe hail threat, once any possible boundary-layer based convective development diminishes. ..Kerr/Thornton.. 11/12/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1132 PM CST Mon Nov 11 2024 Valid 121200Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS EVENING ACROSS PARTS OF THE TEXAS SOUTH PLAINS AND PANHANDLE...AND ADJACENT PORTIONS OF WESTERN OKLAHOMA... ...SUMMARY... A couple of strong thunderstorms may impact parts of the Texas South Plains and Panhandle vicinity this evening, perhaps accompanied by some risk for severe weather. ...Synopsis... The westerlies appear likely to remain a bit more progressive across the eastern mid-latitude Pacific into western North America than farther downstream, from near the Atlantic Seaboard through the Atlantic. Within this regime, another significant mid-level trough, with at least a couple of embedded short wave perturbations, is forecast to approach the Pacific coast later today through tonight. As this occurs, a fairly vigorous perturbation within the southern portion of a splitting preceding trough is likely to continue east of the southern Great Basin, across and east of the southern Rockies by daybreak Wednesday. An associated cold front probably will overtake modest lee surface troughing across central and southern portions of the high plains by late tonight. Before it does, boundary-layer moisture return in a narrow plume emanating from the Rio Grande Valley, beneath steepening lower/mid-tropospheric lapse rates, might contribute to a corridor of weak to modest destabilization by late this afternoon across the Texas South Plains into Panhandle vicinity. ...Southern Great Plains... Near the leading edge of a narrow plume of elevated mixed-layer air forecast to advect north-northeastward through southern portions of the high plains, models indicate that differential surface heating may contribute to a strengthening low-level baroclinic zone across parts of the Texas South Plains and Panhandle by late this afternoon. This will probably become a focus for strengthening near-surface warm advection by early this evening, downstream of the short wave impulse progressing across the southern Rockies. This is likely to coincide with increasing low-level moisture return, which might include boundary-layer dew points as high as the lower 60s F near the immediate vicinity of the surface boundary, southward through the Texas South Plains. With regard to potential for severe storm development late this afternoon into tonight, the signal remains muted in the latest high resolution ensemble output and associated machine learning guidance. However, given the potential for at least a narrow corridor of modest boundary-layer destabilization, which may include mixed-layer CAPE on the order of 500-1000 J/kg, large-scale forcing for ascent and strengthening shear appear conducive to organized convective development. There appears a window of opportunity for the evolution of one or two boundary-layer based supercells across parts of the Texas South Plains into Panhandle, before a more general increase in thunderstorm development ensues northeastward across parts of Oklahoma and Kansas later tonight. Rooted within an increasingly elevated warm advected regime, forecast soundings suggest minimal potential for a continuing severe hail threat, once any possible boundary-layer based convective development diminishes. ..Kerr/Thornton.. 11/12/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1132 PM CST Mon Nov 11 2024 Valid 121200Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS EVENING ACROSS PARTS OF THE TEXAS SOUTH PLAINS AND PANHANDLE...AND ADJACENT PORTIONS OF WESTERN OKLAHOMA... ...SUMMARY... A couple of strong thunderstorms may impact parts of the Texas South Plains and Panhandle vicinity this evening, perhaps accompanied by some risk for severe weather. ...Synopsis... The westerlies appear likely to remain a bit more progressive across the eastern mid-latitude Pacific into western North America than farther downstream, from near the Atlantic Seaboard through the Atlantic. Within this regime, another significant mid-level trough, with at least a couple of embedded short wave perturbations, is forecast to approach the Pacific coast later today through tonight. As this occurs, a fairly vigorous perturbation within the southern portion of a splitting preceding trough is likely to continue east of the southern Great Basin, across and east of the southern Rockies by daybreak Wednesday. An associated cold front probably will overtake modest lee surface troughing across central and southern portions of the high plains by late tonight. Before it does, boundary-layer moisture return in a narrow plume emanating from the Rio Grande Valley, beneath steepening lower/mid-tropospheric lapse rates, might contribute to a corridor of weak to modest destabilization by late this afternoon across the Texas South Plains into Panhandle vicinity. ...Southern Great Plains... Near the leading edge of a narrow plume of elevated mixed-layer air forecast to advect north-northeastward through southern portions of the high plains, models indicate that differential surface heating may contribute to a strengthening low-level baroclinic zone across parts of the Texas South Plains and Panhandle by late this afternoon. This will probably become a focus for strengthening near-surface warm advection by early this evening, downstream of the short wave impulse progressing across the southern Rockies. This is likely to coincide with increasing low-level moisture return, which might include boundary-layer dew points as high as the lower 60s F near the immediate vicinity of the surface boundary, southward through the Texas South Plains. With regard to potential for severe storm development late this afternoon into tonight, the signal remains muted in the latest high resolution ensemble output and associated machine learning guidance. However, given the potential for at least a narrow corridor of modest boundary-layer destabilization, which may include mixed-layer CAPE on the order of 500-1000 J/kg, large-scale forcing for ascent and strengthening shear appear conducive to organized convective development. There appears a window of opportunity for the evolution of one or two boundary-layer based supercells across parts of the Texas South Plains into Panhandle, before a more general increase in thunderstorm development ensues northeastward across parts of Oklahoma and Kansas later tonight. Rooted within an increasingly elevated warm advected regime, forecast soundings suggest minimal potential for a continuing severe hail threat, once any possible boundary-layer based convective development diminishes. ..Kerr/Thornton.. 11/12/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1132 PM CST Mon Nov 11 2024 Valid 121200Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS EVENING ACROSS PARTS OF THE TEXAS SOUTH PLAINS AND PANHANDLE...AND ADJACENT PORTIONS OF WESTERN OKLAHOMA... ...SUMMARY... A couple of strong thunderstorms may impact parts of the Texas South Plains and Panhandle vicinity this evening, perhaps accompanied by some risk for severe weather. ...Synopsis... The westerlies appear likely to remain a bit more progressive across the eastern mid-latitude Pacific into western North America than farther downstream, from near the Atlantic Seaboard through the Atlantic. Within this regime, another significant mid-level trough, with at least a couple of embedded short wave perturbations, is forecast to approach the Pacific coast later today through tonight. As this occurs, a fairly vigorous perturbation within the southern portion of a splitting preceding trough is likely to continue east of the southern Great Basin, across and east of the southern Rockies by daybreak Wednesday. An associated cold front probably will overtake modest lee surface troughing across central and southern portions of the high plains by late tonight. Before it does, boundary-layer moisture return in a narrow plume emanating from the Rio Grande Valley, beneath steepening lower/mid-tropospheric lapse rates, might contribute to a corridor of weak to modest destabilization by late this afternoon across the Texas South Plains into Panhandle vicinity. ...Southern Great Plains... Near the leading edge of a narrow plume of elevated mixed-layer air forecast to advect north-northeastward through southern portions of the high plains, models indicate that differential surface heating may contribute to a strengthening low-level baroclinic zone across parts of the Texas South Plains and Panhandle by late this afternoon. This will probably become a focus for strengthening near-surface warm advection by early this evening, downstream of the short wave impulse progressing across the southern Rockies. This is likely to coincide with increasing low-level moisture return, which might include boundary-layer dew points as high as the lower 60s F near the immediate vicinity of the surface boundary, southward through the Texas South Plains. With regard to potential for severe storm development late this afternoon into tonight, the signal remains muted in the latest high resolution ensemble output and associated machine learning guidance. However, given the potential for at least a narrow corridor of modest boundary-layer destabilization, which may include mixed-layer CAPE on the order of 500-1000 J/kg, large-scale forcing for ascent and strengthening shear appear conducive to organized convective development. There appears a window of opportunity for the evolution of one or two boundary-layer based supercells across parts of the Texas South Plains into Panhandle, before a more general increase in thunderstorm development ensues northeastward across parts of Oklahoma and Kansas later tonight. Rooted within an increasingly elevated warm advected regime, forecast soundings suggest minimal potential for a continuing severe hail threat, once any possible boundary-layer based convective development diminishes. ..Kerr/Thornton.. 11/12/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0647 PM CST Mon Nov 11 2024 Valid 120100Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for severe thunderstorms appears negligible through tonight. ...01Z Update... ...Pacific Coast... A mid-level tongue of cold air (including 500 mb temperatures of -24 to -28C) continues to migrate inland of the Pacific coast. It appears that the axis of coldest air is in the process of shifting to the east of the Sierra Nevada and Cascades. However, latest model output suggests that the mid-level temperatures may remain cold enough to support instability sufficient for a continuing risk of occasional weak convection capable of producing lightning, mainly to the west of the Cascades, through about 06-08Z. ...Lower Great Lakes... Occasional lightning flashes have been evident with convection developing beneath a lower/mid-level cold pool associated with a digging short wave trough across southern Ontario into the lee of Lakes Ontario and Erie. However, with diurnal cooling underway and low-level cold advection ongoing to the lee of the lower Great Lakes, forecast soundings suggest that this activity is unlikely to persist beyond another hour or so. ..Kerr.. 11/12/2024 Read more