Severe Storms

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0121 PM CST Thu Feb 06 2025 Valid 081200Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Aside from low probabilities for scattered thunderstorm development across parts of the Ohio Valley, the risk for thunderstorms appears negligible across much of the U.S., Saturday through Saturday night. ...Discussion... Models indicate that mid-level flow will begin to undergo amplification across the northern mid-latitudes of the eastern Pacific into western North America, including building mid-level ridging across the northeastern Pacific through Alaska and digging downstream troughing east of the Canadian Rockies. Otherwise, it appears that there will be little change across much of the contiguous U.S., with ridging centered over the subtropical latitudes maintaining an influence across much of the southern into central tier states. Within a broadly confluent, zonal regime across the northern tier, a couple of embedded short wave perturbations may consolidate into larger-scale, but still low-amplitude, troughing progressing across the Great Lakes vicinity into Northeast by late Saturday night. It appears that the evolving mid-level trough may provide support for increasingly significant surface cyclogenesis offshore of the northern Mid Atlantic coast by the end of the period. This is likely to be focused along a tightening baroclinic zone, near the eroding southern periphery of a seasonably cold air mass entrenched to the east of the Rockies. Initially stalled across parts of the southern Great Plains into Ohio Valley and southern Mid Atlantic, the surface frontal zone is forecast to advance southward into the Gulf Coast states Saturday through Saturday night, in the wake of the wave. ...Lower Ohio Valley... Model differences concerning the frontal wave development, and potential boundary-layer destabilization, along the eroding shallow southern periphery of the cold air across the interior U.S. remains problematic concerning convective potential. Strengthening of lower/mid-tropospheric wind fields and shear near the frontal wave is likely to become conditionally supportive of severe weather potential, given sufficient destabilization. However, regardless of the boundary-layer modification (and the NAM may be too aggressive with the lingering shallow sharp surface-based inversion across Kentucky, east-northeast of Bowling Green into the Blue Grass by late Saturday afternoon), there does appear a general consensus that relatively warm, dry air at mid-levels may tend to suppress destabilization. At least some convection, perhaps mostly elevated near and north of the Ohio River, may become capable of producing lightning. But the risk for severe weather still appears negligible at this time. ..Kerr.. 02/06/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0121 PM CST Thu Feb 06 2025 Valid 081200Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Aside from low probabilities for scattered thunderstorm development across parts of the Ohio Valley, the risk for thunderstorms appears negligible across much of the U.S., Saturday through Saturday night. ...Discussion... Models indicate that mid-level flow will begin to undergo amplification across the northern mid-latitudes of the eastern Pacific into western North America, including building mid-level ridging across the northeastern Pacific through Alaska and digging downstream troughing east of the Canadian Rockies. Otherwise, it appears that there will be little change across much of the contiguous U.S., with ridging centered over the subtropical latitudes maintaining an influence across much of the southern into central tier states. Within a broadly confluent, zonal regime across the northern tier, a couple of embedded short wave perturbations may consolidate into larger-scale, but still low-amplitude, troughing progressing across the Great Lakes vicinity into Northeast by late Saturday night. It appears that the evolving mid-level trough may provide support for increasingly significant surface cyclogenesis offshore of the northern Mid Atlantic coast by the end of the period. This is likely to be focused along a tightening baroclinic zone, near the eroding southern periphery of a seasonably cold air mass entrenched to the east of the Rockies. Initially stalled across parts of the southern Great Plains into Ohio Valley and southern Mid Atlantic, the surface frontal zone is forecast to advance southward into the Gulf Coast states Saturday through Saturday night, in the wake of the wave. ...Lower Ohio Valley... Model differences concerning the frontal wave development, and potential boundary-layer destabilization, along the eroding shallow southern periphery of the cold air across the interior U.S. remains problematic concerning convective potential. Strengthening of lower/mid-tropospheric wind fields and shear near the frontal wave is likely to become conditionally supportive of severe weather potential, given sufficient destabilization. However, regardless of the boundary-layer modification (and the NAM may be too aggressive with the lingering shallow sharp surface-based inversion across Kentucky, east-northeast of Bowling Green into the Blue Grass by late Saturday afternoon), there does appear a general consensus that relatively warm, dry air at mid-levels may tend to suppress destabilization. At least some convection, perhaps mostly elevated near and north of the Ohio River, may become capable of producing lightning. But the risk for severe weather still appears negligible at this time. ..Kerr.. 02/06/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0121 PM CST Thu Feb 06 2025 Valid 081200Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Aside from low probabilities for scattered thunderstorm development across parts of the Ohio Valley, the risk for thunderstorms appears negligible across much of the U.S., Saturday through Saturday night. ...Discussion... Models indicate that mid-level flow will begin to undergo amplification across the northern mid-latitudes of the eastern Pacific into western North America, including building mid-level ridging across the northeastern Pacific through Alaska and digging downstream troughing east of the Canadian Rockies. Otherwise, it appears that there will be little change across much of the contiguous U.S., with ridging centered over the subtropical latitudes maintaining an influence across much of the southern into central tier states. Within a broadly confluent, zonal regime across the northern tier, a couple of embedded short wave perturbations may consolidate into larger-scale, but still low-amplitude, troughing progressing across the Great Lakes vicinity into Northeast by late Saturday night. It appears that the evolving mid-level trough may provide support for increasingly significant surface cyclogenesis offshore of the northern Mid Atlantic coast by the end of the period. This is likely to be focused along a tightening baroclinic zone, near the eroding southern periphery of a seasonably cold air mass entrenched to the east of the Rockies. Initially stalled across parts of the southern Great Plains into Ohio Valley and southern Mid Atlantic, the surface frontal zone is forecast to advance southward into the Gulf Coast states Saturday through Saturday night, in the wake of the wave. ...Lower Ohio Valley... Model differences concerning the frontal wave development, and potential boundary-layer destabilization, along the eroding shallow southern periphery of the cold air across the interior U.S. remains problematic concerning convective potential. Strengthening of lower/mid-tropospheric wind fields and shear near the frontal wave is likely to become conditionally supportive of severe weather potential, given sufficient destabilization. However, regardless of the boundary-layer modification (and the NAM may be too aggressive with the lingering shallow sharp surface-based inversion across Kentucky, east-northeast of Bowling Green into the Blue Grass by late Saturday afternoon), there does appear a general consensus that relatively warm, dry air at mid-levels may tend to suppress destabilization. At least some convection, perhaps mostly elevated near and north of the Ohio River, may become capable of producing lightning. But the risk for severe weather still appears negligible at this time. ..Kerr.. 02/06/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0121 PM CST Thu Feb 06 2025 Valid 081200Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Aside from low probabilities for scattered thunderstorm development across parts of the Ohio Valley, the risk for thunderstorms appears negligible across much of the U.S., Saturday through Saturday night. ...Discussion... Models indicate that mid-level flow will begin to undergo amplification across the northern mid-latitudes of the eastern Pacific into western North America, including building mid-level ridging across the northeastern Pacific through Alaska and digging downstream troughing east of the Canadian Rockies. Otherwise, it appears that there will be little change across much of the contiguous U.S., with ridging centered over the subtropical latitudes maintaining an influence across much of the southern into central tier states. Within a broadly confluent, zonal regime across the northern tier, a couple of embedded short wave perturbations may consolidate into larger-scale, but still low-amplitude, troughing progressing across the Great Lakes vicinity into Northeast by late Saturday night. It appears that the evolving mid-level trough may provide support for increasingly significant surface cyclogenesis offshore of the northern Mid Atlantic coast by the end of the period. This is likely to be focused along a tightening baroclinic zone, near the eroding southern periphery of a seasonably cold air mass entrenched to the east of the Rockies. Initially stalled across parts of the southern Great Plains into Ohio Valley and southern Mid Atlantic, the surface frontal zone is forecast to advance southward into the Gulf Coast states Saturday through Saturday night, in the wake of the wave. ...Lower Ohio Valley... Model differences concerning the frontal wave development, and potential boundary-layer destabilization, along the eroding shallow southern periphery of the cold air across the interior U.S. remains problematic concerning convective potential. Strengthening of lower/mid-tropospheric wind fields and shear near the frontal wave is likely to become conditionally supportive of severe weather potential, given sufficient destabilization. However, regardless of the boundary-layer modification (and the NAM may be too aggressive with the lingering shallow sharp surface-based inversion across Kentucky, east-northeast of Bowling Green into the Blue Grass by late Saturday afternoon), there does appear a general consensus that relatively warm, dry air at mid-levels may tend to suppress destabilization. At least some convection, perhaps mostly elevated near and north of the Ohio River, may become capable of producing lightning. But the risk for severe weather still appears negligible at this time. ..Kerr.. 02/06/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0121 PM CST Thu Feb 06 2025 Valid 081200Z - 091200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Aside from low probabilities for scattered thunderstorm development across parts of the Ohio Valley, the risk for thunderstorms appears negligible across much of the U.S., Saturday through Saturday night. ...Discussion... Models indicate that mid-level flow will begin to undergo amplification across the northern mid-latitudes of the eastern Pacific into western North America, including building mid-level ridging across the northeastern Pacific through Alaska and digging downstream troughing east of the Canadian Rockies. Otherwise, it appears that there will be little change across much of the contiguous U.S., with ridging centered over the subtropical latitudes maintaining an influence across much of the southern into central tier states. Within a broadly confluent, zonal regime across the northern tier, a couple of embedded short wave perturbations may consolidate into larger-scale, but still low-amplitude, troughing progressing across the Great Lakes vicinity into Northeast by late Saturday night. It appears that the evolving mid-level trough may provide support for increasingly significant surface cyclogenesis offshore of the northern Mid Atlantic coast by the end of the period. This is likely to be focused along a tightening baroclinic zone, near the eroding southern periphery of a seasonably cold air mass entrenched to the east of the Rockies. Initially stalled across parts of the southern Great Plains into Ohio Valley and southern Mid Atlantic, the surface frontal zone is forecast to advance southward into the Gulf Coast states Saturday through Saturday night, in the wake of the wave. ...Lower Ohio Valley... Model differences concerning the frontal wave development, and potential boundary-layer destabilization, along the eroding shallow southern periphery of the cold air across the interior U.S. remains problematic concerning convective potential. Strengthening of lower/mid-tropospheric wind fields and shear near the frontal wave is likely to become conditionally supportive of severe weather potential, given sufficient destabilization. However, regardless of the boundary-layer modification (and the NAM may be too aggressive with the lingering shallow sharp surface-based inversion across Kentucky, east-northeast of Bowling Green into the Blue Grass by late Saturday afternoon), there does appear a general consensus that relatively warm, dry air at mid-levels may tend to suppress destabilization. At least some convection, perhaps mostly elevated near and north of the Ohio River, may become capable of producing lightning. But the risk for severe weather still appears negligible at this time. ..Kerr.. 02/06/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1105 AM CST Thu Feb 06 2025 Valid 071200Z - 081200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Aside from some potential for a couple of weak thunderstorms across parts of the northern Rockies vicinity, the risk for thunderstorms appears negligible across much of the U.S., Friday through Friday night. ...Discussion... Models indicate that broad mid/upper ridging will be maintained across the subtropical latitudes, from northern Mexico through the western Atlantic, and a prominent influence across the southern into central tier of the U.S. through this period, downstream of persistent ridging in the northern mid-latitudes, and troughing in the southern mid- to subtropic latitudes, of the eastern Pacific. To the east of the northeastern Pacific ridging, broad mean troughing, with more progressive embedded smaller-scale perturbations, is forecast to linger across British Columbia and the Pacific Northwest, while developing eastward across the Canadian Prairies, northern U.S. Rockies and Great Plains. Beneath this regime, guidance indicates potential for modest surface cyclogenesis across eastern Colorado through areas near/south of the Kansas/Oklahoma border vicinity. There appears better consensus among the models, particularly the ECENS/ECMWF and GEFS/GFS. But this output may still be having issues handling ongoing reinforcing cold intrusions to the lee of Rockies. The NAM and Rapid Refresh remain slower to erode the colder boundary-layer across the Texas South Plains into central Oklahoma vicinity, and are slower and weaker with the evolving surface wave. Otherwise, a gradual erosion, from south to north, of the shallow leading edge of the entrenched cold air mass is possible, beneath a continuing southerly to westerly return flow across parts of the southeastern Great Plains into southern Mid Atlantic. However, it appears that associated moisture emanating from a modifying western Gulf boundary layer will not become supportive of more than weak destabilization, or an appreciable risk for thunderstorms, due to negligible forcing for ascent and warm, capping layers aloft. ...Pacific Northwest into northern Great Plains... Models do indicate that forcing for ascent and cooling mid-levels may contribute to pockets of weak destabilization across parts of the Pacific Northwest into northern Great Plains during this period. However, based on the latest NAM and Rapid Refresh forecast soundings, the calibrated High Resolution Ensemble Forecast guidance might be too aggressive with probabilities for thunderstorms across the eastern Great Basin into northern Rockies vicinity for Friday afternoon and evening. Instability will probably be sufficient to support scattered to numerous snow and rain showers. However, whether the boundary layer in higher elevations warms enough, or convection initiating in lower elevations deepens through sufficiently cold layers aloft, to support an appreciable risk for lightning remains a bit unclear. ..Kerr.. 02/06/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1105 AM CST Thu Feb 06 2025 Valid 071200Z - 081200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Aside from some potential for a couple of weak thunderstorms across parts of the northern Rockies vicinity, the risk for thunderstorms appears negligible across much of the U.S., Friday through Friday night. ...Discussion... Models indicate that broad mid/upper ridging will be maintained across the subtropical latitudes, from northern Mexico through the western Atlantic, and a prominent influence across the southern into central tier of the U.S. through this period, downstream of persistent ridging in the northern mid-latitudes, and troughing in the southern mid- to subtropic latitudes, of the eastern Pacific. To the east of the northeastern Pacific ridging, broad mean troughing, with more progressive embedded smaller-scale perturbations, is forecast to linger across British Columbia and the Pacific Northwest, while developing eastward across the Canadian Prairies, northern U.S. Rockies and Great Plains. Beneath this regime, guidance indicates potential for modest surface cyclogenesis across eastern Colorado through areas near/south of the Kansas/Oklahoma border vicinity. There appears better consensus among the models, particularly the ECENS/ECMWF and GEFS/GFS. But this output may still be having issues handling ongoing reinforcing cold intrusions to the lee of Rockies. The NAM and Rapid Refresh remain slower to erode the colder boundary-layer across the Texas South Plains into central Oklahoma vicinity, and are slower and weaker with the evolving surface wave. Otherwise, a gradual erosion, from south to north, of the shallow leading edge of the entrenched cold air mass is possible, beneath a continuing southerly to westerly return flow across parts of the southeastern Great Plains into southern Mid Atlantic. However, it appears that associated moisture emanating from a modifying western Gulf boundary layer will not become supportive of more than weak destabilization, or an appreciable risk for thunderstorms, due to negligible forcing for ascent and warm, capping layers aloft. ...Pacific Northwest into northern Great Plains... Models do indicate that forcing for ascent and cooling mid-levels may contribute to pockets of weak destabilization across parts of the Pacific Northwest into northern Great Plains during this period. However, based on the latest NAM and Rapid Refresh forecast soundings, the calibrated High Resolution Ensemble Forecast guidance might be too aggressive with probabilities for thunderstorms across the eastern Great Basin into northern Rockies vicinity for Friday afternoon and evening. Instability will probably be sufficient to support scattered to numerous snow and rain showers. However, whether the boundary layer in higher elevations warms enough, or convection initiating in lower elevations deepens through sufficiently cold layers aloft, to support an appreciable risk for lightning remains a bit unclear. ..Kerr.. 02/06/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1105 AM CST Thu Feb 06 2025 Valid 071200Z - 081200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Aside from some potential for a couple of weak thunderstorms across parts of the northern Rockies vicinity, the risk for thunderstorms appears negligible across much of the U.S., Friday through Friday night. ...Discussion... Models indicate that broad mid/upper ridging will be maintained across the subtropical latitudes, from northern Mexico through the western Atlantic, and a prominent influence across the southern into central tier of the U.S. through this period, downstream of persistent ridging in the northern mid-latitudes, and troughing in the southern mid- to subtropic latitudes, of the eastern Pacific. To the east of the northeastern Pacific ridging, broad mean troughing, with more progressive embedded smaller-scale perturbations, is forecast to linger across British Columbia and the Pacific Northwest, while developing eastward across the Canadian Prairies, northern U.S. Rockies and Great Plains. Beneath this regime, guidance indicates potential for modest surface cyclogenesis across eastern Colorado through areas near/south of the Kansas/Oklahoma border vicinity. There appears better consensus among the models, particularly the ECENS/ECMWF and GEFS/GFS. But this output may still be having issues handling ongoing reinforcing cold intrusions to the lee of Rockies. The NAM and Rapid Refresh remain slower to erode the colder boundary-layer across the Texas South Plains into central Oklahoma vicinity, and are slower and weaker with the evolving surface wave. Otherwise, a gradual erosion, from south to north, of the shallow leading edge of the entrenched cold air mass is possible, beneath a continuing southerly to westerly return flow across parts of the southeastern Great Plains into southern Mid Atlantic. However, it appears that associated moisture emanating from a modifying western Gulf boundary layer will not become supportive of more than weak destabilization, or an appreciable risk for thunderstorms, due to negligible forcing for ascent and warm, capping layers aloft. ...Pacific Northwest into northern Great Plains... Models do indicate that forcing for ascent and cooling mid-levels may contribute to pockets of weak destabilization across parts of the Pacific Northwest into northern Great Plains during this period. However, based on the latest NAM and Rapid Refresh forecast soundings, the calibrated High Resolution Ensemble Forecast guidance might be too aggressive with probabilities for thunderstorms across the eastern Great Basin into northern Rockies vicinity for Friday afternoon and evening. Instability will probably be sufficient to support scattered to numerous snow and rain showers. However, whether the boundary layer in higher elevations warms enough, or convection initiating in lower elevations deepens through sufficiently cold layers aloft, to support an appreciable risk for lightning remains a bit unclear. ..Kerr.. 02/06/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1105 AM CST Thu Feb 06 2025 Valid 071200Z - 081200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Aside from some potential for a couple of weak thunderstorms across parts of the northern Rockies vicinity, the risk for thunderstorms appears negligible across much of the U.S., Friday through Friday night. ...Discussion... Models indicate that broad mid/upper ridging will be maintained across the subtropical latitudes, from northern Mexico through the western Atlantic, and a prominent influence across the southern into central tier of the U.S. through this period, downstream of persistent ridging in the northern mid-latitudes, and troughing in the southern mid- to subtropic latitudes, of the eastern Pacific. To the east of the northeastern Pacific ridging, broad mean troughing, with more progressive embedded smaller-scale perturbations, is forecast to linger across British Columbia and the Pacific Northwest, while developing eastward across the Canadian Prairies, northern U.S. Rockies and Great Plains. Beneath this regime, guidance indicates potential for modest surface cyclogenesis across eastern Colorado through areas near/south of the Kansas/Oklahoma border vicinity. There appears better consensus among the models, particularly the ECENS/ECMWF and GEFS/GFS. But this output may still be having issues handling ongoing reinforcing cold intrusions to the lee of Rockies. The NAM and Rapid Refresh remain slower to erode the colder boundary-layer across the Texas South Plains into central Oklahoma vicinity, and are slower and weaker with the evolving surface wave. Otherwise, a gradual erosion, from south to north, of the shallow leading edge of the entrenched cold air mass is possible, beneath a continuing southerly to westerly return flow across parts of the southeastern Great Plains into southern Mid Atlantic. However, it appears that associated moisture emanating from a modifying western Gulf boundary layer will not become supportive of more than weak destabilization, or an appreciable risk for thunderstorms, due to negligible forcing for ascent and warm, capping layers aloft. ...Pacific Northwest into northern Great Plains... Models do indicate that forcing for ascent and cooling mid-levels may contribute to pockets of weak destabilization across parts of the Pacific Northwest into northern Great Plains during this period. However, based on the latest NAM and Rapid Refresh forecast soundings, the calibrated High Resolution Ensemble Forecast guidance might be too aggressive with probabilities for thunderstorms across the eastern Great Basin into northern Rockies vicinity for Friday afternoon and evening. Instability will probably be sufficient to support scattered to numerous snow and rain showers. However, whether the boundary layer in higher elevations warms enough, or convection initiating in lower elevations deepens through sufficiently cold layers aloft, to support an appreciable risk for lightning remains a bit unclear. ..Kerr.. 02/06/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1105 AM CST Thu Feb 06 2025 Valid 071200Z - 081200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Aside from some potential for a couple of weak thunderstorms across parts of the northern Rockies vicinity, the risk for thunderstorms appears negligible across much of the U.S., Friday through Friday night. ...Discussion... Models indicate that broad mid/upper ridging will be maintained across the subtropical latitudes, from northern Mexico through the western Atlantic, and a prominent influence across the southern into central tier of the U.S. through this period, downstream of persistent ridging in the northern mid-latitudes, and troughing in the southern mid- to subtropic latitudes, of the eastern Pacific. To the east of the northeastern Pacific ridging, broad mean troughing, with more progressive embedded smaller-scale perturbations, is forecast to linger across British Columbia and the Pacific Northwest, while developing eastward across the Canadian Prairies, northern U.S. Rockies and Great Plains. Beneath this regime, guidance indicates potential for modest surface cyclogenesis across eastern Colorado through areas near/south of the Kansas/Oklahoma border vicinity. There appears better consensus among the models, particularly the ECENS/ECMWF and GEFS/GFS. But this output may still be having issues handling ongoing reinforcing cold intrusions to the lee of Rockies. The NAM and Rapid Refresh remain slower to erode the colder boundary-layer across the Texas South Plains into central Oklahoma vicinity, and are slower and weaker with the evolving surface wave. Otherwise, a gradual erosion, from south to north, of the shallow leading edge of the entrenched cold air mass is possible, beneath a continuing southerly to westerly return flow across parts of the southeastern Great Plains into southern Mid Atlantic. However, it appears that associated moisture emanating from a modifying western Gulf boundary layer will not become supportive of more than weak destabilization, or an appreciable risk for thunderstorms, due to negligible forcing for ascent and warm, capping layers aloft. ...Pacific Northwest into northern Great Plains... Models do indicate that forcing for ascent and cooling mid-levels may contribute to pockets of weak destabilization across parts of the Pacific Northwest into northern Great Plains during this period. However, based on the latest NAM and Rapid Refresh forecast soundings, the calibrated High Resolution Ensemble Forecast guidance might be too aggressive with probabilities for thunderstorms across the eastern Great Basin into northern Rockies vicinity for Friday afternoon and evening. Instability will probably be sufficient to support scattered to numerous snow and rain showers. However, whether the boundary layer in higher elevations warms enough, or convection initiating in lower elevations deepens through sufficiently cold layers aloft, to support an appreciable risk for lightning remains a bit unclear. ..Kerr.. 02/06/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1105 AM CST Thu Feb 06 2025 Valid 071200Z - 081200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Aside from some potential for a couple of weak thunderstorms across parts of the northern Rockies vicinity, the risk for thunderstorms appears negligible across much of the U.S., Friday through Friday night. ...Discussion... Models indicate that broad mid/upper ridging will be maintained across the subtropical latitudes, from northern Mexico through the western Atlantic, and a prominent influence across the southern into central tier of the U.S. through this period, downstream of persistent ridging in the northern mid-latitudes, and troughing in the southern mid- to subtropic latitudes, of the eastern Pacific. To the east of the northeastern Pacific ridging, broad mean troughing, with more progressive embedded smaller-scale perturbations, is forecast to linger across British Columbia and the Pacific Northwest, while developing eastward across the Canadian Prairies, northern U.S. Rockies and Great Plains. Beneath this regime, guidance indicates potential for modest surface cyclogenesis across eastern Colorado through areas near/south of the Kansas/Oklahoma border vicinity. There appears better consensus among the models, particularly the ECENS/ECMWF and GEFS/GFS. But this output may still be having issues handling ongoing reinforcing cold intrusions to the lee of Rockies. The NAM and Rapid Refresh remain slower to erode the colder boundary-layer across the Texas South Plains into central Oklahoma vicinity, and are slower and weaker with the evolving surface wave. Otherwise, a gradual erosion, from south to north, of the shallow leading edge of the entrenched cold air mass is possible, beneath a continuing southerly to westerly return flow across parts of the southeastern Great Plains into southern Mid Atlantic. However, it appears that associated moisture emanating from a modifying western Gulf boundary layer will not become supportive of more than weak destabilization, or an appreciable risk for thunderstorms, due to negligible forcing for ascent and warm, capping layers aloft. ...Pacific Northwest into northern Great Plains... Models do indicate that forcing for ascent and cooling mid-levels may contribute to pockets of weak destabilization across parts of the Pacific Northwest into northern Great Plains during this period. However, based on the latest NAM and Rapid Refresh forecast soundings, the calibrated High Resolution Ensemble Forecast guidance might be too aggressive with probabilities for thunderstorms across the eastern Great Basin into northern Rockies vicinity for Friday afternoon and evening. Instability will probably be sufficient to support scattered to numerous snow and rain showers. However, whether the boundary layer in higher elevations warms enough, or convection initiating in lower elevations deepens through sufficiently cold layers aloft, to support an appreciable risk for lightning remains a bit unclear. ..Kerr.. 02/06/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1105 AM CST Thu Feb 06 2025 Valid 071200Z - 081200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Aside from some potential for a couple of weak thunderstorms across parts of the northern Rockies vicinity, the risk for thunderstorms appears negligible across much of the U.S., Friday through Friday night. ...Discussion... Models indicate that broad mid/upper ridging will be maintained across the subtropical latitudes, from northern Mexico through the western Atlantic, and a prominent influence across the southern into central tier of the U.S. through this period, downstream of persistent ridging in the northern mid-latitudes, and troughing in the southern mid- to subtropic latitudes, of the eastern Pacific. To the east of the northeastern Pacific ridging, broad mean troughing, with more progressive embedded smaller-scale perturbations, is forecast to linger across British Columbia and the Pacific Northwest, while developing eastward across the Canadian Prairies, northern U.S. Rockies and Great Plains. Beneath this regime, guidance indicates potential for modest surface cyclogenesis across eastern Colorado through areas near/south of the Kansas/Oklahoma border vicinity. There appears better consensus among the models, particularly the ECENS/ECMWF and GEFS/GFS. But this output may still be having issues handling ongoing reinforcing cold intrusions to the lee of Rockies. The NAM and Rapid Refresh remain slower to erode the colder boundary-layer across the Texas South Plains into central Oklahoma vicinity, and are slower and weaker with the evolving surface wave. Otherwise, a gradual erosion, from south to north, of the shallow leading edge of the entrenched cold air mass is possible, beneath a continuing southerly to westerly return flow across parts of the southeastern Great Plains into southern Mid Atlantic. However, it appears that associated moisture emanating from a modifying western Gulf boundary layer will not become supportive of more than weak destabilization, or an appreciable risk for thunderstorms, due to negligible forcing for ascent and warm, capping layers aloft. ...Pacific Northwest into northern Great Plains... Models do indicate that forcing for ascent and cooling mid-levels may contribute to pockets of weak destabilization across parts of the Pacific Northwest into northern Great Plains during this period. However, based on the latest NAM and Rapid Refresh forecast soundings, the calibrated High Resolution Ensemble Forecast guidance might be too aggressive with probabilities for thunderstorms across the eastern Great Basin into northern Rockies vicinity for Friday afternoon and evening. Instability will probably be sufficient to support scattered to numerous snow and rain showers. However, whether the boundary layer in higher elevations warms enough, or convection initiating in lower elevations deepens through sufficiently cold layers aloft, to support an appreciable risk for lightning remains a bit unclear. ..Kerr.. 02/06/2025 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1028 AM CST Thu Feb 06 2025 Valid 061700Z - 071200Z The previous forecast remains on track, with only minor adjustments made to the forecast to reflect the latest high-resolution guidance consensus. ..Squitieri.. 02/06/2025 .PREV DISCUSSION... /ISSUED 0154 AM CST Thu Feb 06 2025/ ...Synopsis... Zonal, mid-level flow is forecast to continue across the central and western US today and tonight. Embedded within the westerly flow, several weak perturbations will cross the Rockies enhancing a lee trough over the High Plains. ...Southwest and Southern High Plains... Dry and breezy conditions are again expected across parts of eastern AZ and NM today as strong westerly flow continues over the Rockies. Several embedded mid-level perturbations will help strengthen lee troughing, and the resulting west/southwesterly surface winds to 15-25 mph. The strong downslope winds, along with warm temperatures and days of low humidity will support afternoon RH values of 10-15%. Given the favorable overlap of strong winds, low humidity and ongoing drought, widespread elevated fire-weather conditions are likely. A few hours of locally critical fire-weather conditions also appear possible within areas of stronger terrain-enhanced wind gusts. However, confidence in widespread critical conditions is relatively low. ...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 1028 AM CST Thu Feb 06 2025 Valid 061700Z - 071200Z The previous forecast remains on track, with only minor adjustments made to the forecast to reflect the latest high-resolution guidance consensus. ..Squitieri.. 02/06/2025 .PREV DISCUSSION... /ISSUED 0154 AM CST Thu Feb 06 2025/ ...Synopsis... Zonal, mid-level flow is forecast to continue across the central and western US today and tonight. Embedded within the westerly flow, several weak perturbations will cross the Rockies enhancing a lee trough over the High Plains. ...Southwest and Southern High Plains... Dry and breezy conditions are again expected across parts of eastern AZ and NM today as strong westerly flow continues over the Rockies. Several embedded mid-level perturbations will help strengthen lee troughing, and the resulting west/southwesterly surface winds to 15-25 mph. The strong downslope winds, along with warm temperatures and days of low humidity will support afternoon RH values of 10-15%. Given the favorable overlap of strong winds, low humidity and ongoing drought, widespread elevated fire-weather conditions are likely. A few hours of locally critical fire-weather conditions also appear possible within areas of stronger terrain-enhanced wind gusts. However, confidence in widespread critical conditions is relatively low. ...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 1028 AM CST Thu Feb 06 2025 Valid 061700Z - 071200Z The previous forecast remains on track, with only minor adjustments made to the forecast to reflect the latest high-resolution guidance consensus. ..Squitieri.. 02/06/2025 .PREV DISCUSSION... /ISSUED 0154 AM CST Thu Feb 06 2025/ ...Synopsis... Zonal, mid-level flow is forecast to continue across the central and western US today and tonight. Embedded within the westerly flow, several weak perturbations will cross the Rockies enhancing a lee trough over the High Plains. ...Southwest and Southern High Plains... Dry and breezy conditions are again expected across parts of eastern AZ and NM today as strong westerly flow continues over the Rockies. Several embedded mid-level perturbations will help strengthen lee troughing, and the resulting west/southwesterly surface winds to 15-25 mph. The strong downslope winds, along with warm temperatures and days of low humidity will support afternoon RH values of 10-15%. Given the favorable overlap of strong winds, low humidity and ongoing drought, widespread elevated fire-weather conditions are likely. A few hours of locally critical fire-weather conditions also appear possible within areas of stronger terrain-enhanced wind gusts. However, confidence in widespread critical conditions is relatively low. ...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 1028 AM CST Thu Feb 06 2025 Valid 061700Z - 071200Z The previous forecast remains on track, with only minor adjustments made to the forecast to reflect the latest high-resolution guidance consensus. ..Squitieri.. 02/06/2025 .PREV DISCUSSION... /ISSUED 0154 AM CST Thu Feb 06 2025/ ...Synopsis... Zonal, mid-level flow is forecast to continue across the central and western US today and tonight. Embedded within the westerly flow, several weak perturbations will cross the Rockies enhancing a lee trough over the High Plains. ...Southwest and Southern High Plains... Dry and breezy conditions are again expected across parts of eastern AZ and NM today as strong westerly flow continues over the Rockies. Several embedded mid-level perturbations will help strengthen lee troughing, and the resulting west/southwesterly surface winds to 15-25 mph. The strong downslope winds, along with warm temperatures and days of low humidity will support afternoon RH values of 10-15%. Given the favorable overlap of strong winds, low humidity and ongoing drought, widespread elevated fire-weather conditions are likely. A few hours of locally critical fire-weather conditions also appear possible within areas of stronger terrain-enhanced wind gusts. However, confidence in widespread critical conditions is relatively low. ...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 1028 AM CST Thu Feb 06 2025 Valid 061700Z - 071200Z The previous forecast remains on track, with only minor adjustments made to the forecast to reflect the latest high-resolution guidance consensus. ..Squitieri.. 02/06/2025 .PREV DISCUSSION... /ISSUED 0154 AM CST Thu Feb 06 2025/ ...Synopsis... Zonal, mid-level flow is forecast to continue across the central and western US today and tonight. Embedded within the westerly flow, several weak perturbations will cross the Rockies enhancing a lee trough over the High Plains. ...Southwest and Southern High Plains... Dry and breezy conditions are again expected across parts of eastern AZ and NM today as strong westerly flow continues over the Rockies. Several embedded mid-level perturbations will help strengthen lee troughing, and the resulting west/southwesterly surface winds to 15-25 mph. The strong downslope winds, along with warm temperatures and days of low humidity will support afternoon RH values of 10-15%. Given the favorable overlap of strong winds, low humidity and ongoing drought, widespread elevated fire-weather conditions are likely. A few hours of locally critical fire-weather conditions also appear possible within areas of stronger terrain-enhanced wind gusts. However, confidence in widespread critical conditions is relatively low. ...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 1028 AM CST Thu Feb 06 2025 Valid 061700Z - 071200Z The previous forecast remains on track, with only minor adjustments made to the forecast to reflect the latest high-resolution guidance consensus. ..Squitieri.. 02/06/2025 .PREV DISCUSSION... /ISSUED 0154 AM CST Thu Feb 06 2025/ ...Synopsis... Zonal, mid-level flow is forecast to continue across the central and western US today and tonight. Embedded within the westerly flow, several weak perturbations will cross the Rockies enhancing a lee trough over the High Plains. ...Southwest and Southern High Plains... Dry and breezy conditions are again expected across parts of eastern AZ and NM today as strong westerly flow continues over the Rockies. Several embedded mid-level perturbations will help strengthen lee troughing, and the resulting west/southwesterly surface winds to 15-25 mph. The strong downslope winds, along with warm temperatures and days of low humidity will support afternoon RH values of 10-15%. Given the favorable overlap of strong winds, low humidity and ongoing drought, widespread elevated fire-weather conditions are likely. A few hours of locally critical fire-weather conditions also appear possible within areas of stronger terrain-enhanced wind gusts. However, confidence in widespread critical conditions is relatively low. ...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 1008 AM CST Thu Feb 06 2025 Valid 061630Z - 071200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING OVER PORTIONS OF TENNESSEE AND VICINITY.... ...SUMMARY... A few strong/severe thunderstorms are expected this afternoon and evening across parts of the Tennessee Valley. ...TN and vicinity... Morning visible satellite imagery shows a surface cold front extending from northwest TN into southern KY. The air mass along and south of the front continues to slowly moisten with dewpoints now in the 60s across most of western/middle TN, and cloud cover appears to be thinning. This will lead to a zone of 1000-1500 J/kg surface-based CAPE this afternoon. Most 12z model solutions indicate scattered thunderstorms will form along the front and track east-southeastward across much of TN through the afternoon/evening. Low-level wind fields are considerably weaker than last night, suggesting the overall tornado risk has likely decreased. However, mid-level lapse rates around 7 C/km, weak forcing, strong westerly flow aloft, and diurnal heating suggest the risk of a few discrete rotating/bowing storms capable of hail and damaging wind gusts. A tornado or two is possible. The threat may persist after dark in east TN, but should weaken as storms move into less instability over the mountains. ..Hart/Jirak.. 02/06/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1008 AM CST Thu Feb 06 2025 Valid 061630Z - 071200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING OVER PORTIONS OF TENNESSEE AND VICINITY.... ...SUMMARY... A few strong/severe thunderstorms are expected this afternoon and evening across parts of the Tennessee Valley. ...TN and vicinity... Morning visible satellite imagery shows a surface cold front extending from northwest TN into southern KY. The air mass along and south of the front continues to slowly moisten with dewpoints now in the 60s across most of western/middle TN, and cloud cover appears to be thinning. This will lead to a zone of 1000-1500 J/kg surface-based CAPE this afternoon. Most 12z model solutions indicate scattered thunderstorms will form along the front and track east-southeastward across much of TN through the afternoon/evening. Low-level wind fields are considerably weaker than last night, suggesting the overall tornado risk has likely decreased. However, mid-level lapse rates around 7 C/km, weak forcing, strong westerly flow aloft, and diurnal heating suggest the risk of a few discrete rotating/bowing storms capable of hail and damaging wind gusts. A tornado or two is possible. The threat may persist after dark in east TN, but should weaken as storms move into less instability over the mountains. ..Hart/Jirak.. 02/06/2025 Read more