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SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0644 AM CST Mon Nov 11 2024 Valid 111300Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms appear unlikely through tonight. ...Synopsis/Discussion... In mid/upper levels, troughing will cross the Great Lakes and West Coast regions this period, with a substantial synoptic-scale ridge in between, across the Great Plains. The western trough will cross most of the Pacific Coast between 18-00Z today, then progress to near a line from GEG-BOI-ELY-PHX to Hermosillo, MX. In the lengthy zone of strong large-scale ascent/cooling aloft that precedes the trough, isolated thunderstorms already have been noted offshore, and over the southwestern OR Coast. This potential will spread inland today until the trough moves past at least marginally favorable low/middle-level moisture to support deep convection. Elsewhere, thunder potential will be minimal, except for part of the central Gulf Coast from near the mouth of the Mississippi River to around PNS. Isolated to widely scattered, episodic thunderstorms will be possible near an inverted trough and convergence zone in low levels, extending northeastward from the weakening, post-tropical remains of Rafael. Though most of the convection will remain over the Gulf, isolated thunderstorms are possible in the outlook area. ..Edwards/Bentley.. 11/11/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0644 AM CST Mon Nov 11 2024 Valid 111300Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms appear unlikely through tonight. ...Synopsis/Discussion... In mid/upper levels, troughing will cross the Great Lakes and West Coast regions this period, with a substantial synoptic-scale ridge in between, across the Great Plains. The western trough will cross most of the Pacific Coast between 18-00Z today, then progress to near a line from GEG-BOI-ELY-PHX to Hermosillo, MX. In the lengthy zone of strong large-scale ascent/cooling aloft that precedes the trough, isolated thunderstorms already have been noted offshore, and over the southwestern OR Coast. This potential will spread inland today until the trough moves past at least marginally favorable low/middle-level moisture to support deep convection. Elsewhere, thunder potential will be minimal, except for part of the central Gulf Coast from near the mouth of the Mississippi River to around PNS. Isolated to widely scattered, episodic thunderstorms will be possible near an inverted trough and convergence zone in low levels, extending northeastward from the weakening, post-tropical remains of Rafael. Though most of the convection will remain over the Gulf, isolated thunderstorms are possible in the outlook area. ..Edwards/Bentley.. 11/11/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0644 AM CST Mon Nov 11 2024 Valid 111300Z - 121200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms appear unlikely through tonight. ...Synopsis/Discussion... In mid/upper levels, troughing will cross the Great Lakes and West Coast regions this period, with a substantial synoptic-scale ridge in between, across the Great Plains. The western trough will cross most of the Pacific Coast between 18-00Z today, then progress to near a line from GEG-BOI-ELY-PHX to Hermosillo, MX. In the lengthy zone of strong large-scale ascent/cooling aloft that precedes the trough, isolated thunderstorms already have been noted offshore, and over the southwestern OR Coast. This potential will spread inland today until the trough moves past at least marginally favorable low/middle-level moisture to support deep convection. Elsewhere, thunder potential will be minimal, except for part of the central Gulf Coast from near the mouth of the Mississippi River to around PNS. Isolated to widely scattered, episodic thunderstorms will be possible near an inverted trough and convergence zone in low levels, extending northeastward from the weakening, post-tropical remains of Rafael. Though most of the convection will remain over the Gulf, isolated thunderstorms are possible in the outlook area. ..Edwards/Bentley.. 11/11/2024 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0356 AM CST Mon Nov 11 2024 Valid 141200Z - 191200Z ...DISCUSSION... A shortwave trough should exit the Lower to Mid-Atlantic Coast on D4/Thursday, with amplification discrepancies from D3 persisting. The 00Z ECMWF appears to be the remaining holdout of the deterministic guidance for a low-probability severe threat in the northeast Gulf Coast vicinity. Still, even it suggests low-level flow should both decrease and become veered through the day, where rich low-level moisture exists. Instability appears likely to be meager and overall severe potential appears low. The next broad mid/upper trough should progress into the West by D5/Friday. Guidance appears to be coalescing towards two distinct shortwave impulses evolving within this longwave pattern. The lead one is progged to track northeast into the northern Great Plains and then pivot east across the Upper Midwest/south-central Canada over the weekend. Meanwhile, a basal shortwave impulse should become established off the southern CA coast. This may gradually move east over the Desert Southwest and northwest Mexico late in the period. Guidance continues to differ with the degree of continental airmass intrusion into the northern Gulf, in the wake of the shortwave trough departing the East on D4. Overall trends and likelihood of surface ridging persisting across parts of the Gulf Coast suggest that returning moisture will probably be of low quality in advance of the north-central states wave. However, this may yield multiple days of return flow and an increasingly moist warm sector becoming established over the southern Great Plains by D8/Monday. SPC GEFS-based ML guidance has trended down to a 2 percent probability for D6/Saturday, after depicting a 15 percent area yesterday. It has instead, increased probabilities to 15 percent on D7/Sunday. Meanwhile, NSSL GEFS-based ML guidance has decreased probabilities for D7 from 10 percent yesterday to 5 percent today. Both of these are 5 percent or less on D8, when the ECMWF ensemble mean would be more indicative of 15 percent potential. Given the lack of consistency, a severe weather highlight for D7 or D8 appears premature but bears watching in later cycles. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0356 AM CST Mon Nov 11 2024 Valid 141200Z - 191200Z ...DISCUSSION... A shortwave trough should exit the Lower to Mid-Atlantic Coast on D4/Thursday, with amplification discrepancies from D3 persisting. The 00Z ECMWF appears to be the remaining holdout of the deterministic guidance for a low-probability severe threat in the northeast Gulf Coast vicinity. Still, even it suggests low-level flow should both decrease and become veered through the day, where rich low-level moisture exists. Instability appears likely to be meager and overall severe potential appears low. The next broad mid/upper trough should progress into the West by D5/Friday. Guidance appears to be coalescing towards two distinct shortwave impulses evolving within this longwave pattern. The lead one is progged to track northeast into the northern Great Plains and then pivot east across the Upper Midwest/south-central Canada over the weekend. Meanwhile, a basal shortwave impulse should become established off the southern CA coast. This may gradually move east over the Desert Southwest and northwest Mexico late in the period. Guidance continues to differ with the degree of continental airmass intrusion into the northern Gulf, in the wake of the shortwave trough departing the East on D4. Overall trends and likelihood of surface ridging persisting across parts of the Gulf Coast suggest that returning moisture will probably be of low quality in advance of the north-central states wave. However, this may yield multiple days of return flow and an increasingly moist warm sector becoming established over the southern Great Plains by D8/Monday. SPC GEFS-based ML guidance has trended down to a 2 percent probability for D6/Saturday, after depicting a 15 percent area yesterday. It has instead, increased probabilities to 15 percent on D7/Sunday. Meanwhile, NSSL GEFS-based ML guidance has decreased probabilities for D7 from 10 percent yesterday to 5 percent today. Both of these are 5 percent or less on D8, when the ECMWF ensemble mean would be more indicative of 15 percent potential. Given the lack of consistency, a severe weather highlight for D7 or D8 appears premature but bears watching in later cycles. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0356 AM CST Mon Nov 11 2024 Valid 141200Z - 191200Z ...DISCUSSION... A shortwave trough should exit the Lower to Mid-Atlantic Coast on D4/Thursday, with amplification discrepancies from D3 persisting. The 00Z ECMWF appears to be the remaining holdout of the deterministic guidance for a low-probability severe threat in the northeast Gulf Coast vicinity. Still, even it suggests low-level flow should both decrease and become veered through the day, where rich low-level moisture exists. Instability appears likely to be meager and overall severe potential appears low. The next broad mid/upper trough should progress into the West by D5/Friday. Guidance appears to be coalescing towards two distinct shortwave impulses evolving within this longwave pattern. The lead one is progged to track northeast into the northern Great Plains and then pivot east across the Upper Midwest/south-central Canada over the weekend. Meanwhile, a basal shortwave impulse should become established off the southern CA coast. This may gradually move east over the Desert Southwest and northwest Mexico late in the period. Guidance continues to differ with the degree of continental airmass intrusion into the northern Gulf, in the wake of the shortwave trough departing the East on D4. Overall trends and likelihood of surface ridging persisting across parts of the Gulf Coast suggest that returning moisture will probably be of low quality in advance of the north-central states wave. However, this may yield multiple days of return flow and an increasingly moist warm sector becoming established over the southern Great Plains by D8/Monday. SPC GEFS-based ML guidance has trended down to a 2 percent probability for D6/Saturday, after depicting a 15 percent area yesterday. It has instead, increased probabilities to 15 percent on D7/Sunday. Meanwhile, NSSL GEFS-based ML guidance has decreased probabilities for D7 from 10 percent yesterday to 5 percent today. Both of these are 5 percent or less on D8, when the ECMWF ensemble mean would be more indicative of 15 percent potential. Given the lack of consistency, a severe weather highlight for D7 or D8 appears premature but bears watching in later cycles. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0356 AM CST Mon Nov 11 2024 Valid 141200Z - 191200Z ...DISCUSSION... A shortwave trough should exit the Lower to Mid-Atlantic Coast on D4/Thursday, with amplification discrepancies from D3 persisting. The 00Z ECMWF appears to be the remaining holdout of the deterministic guidance for a low-probability severe threat in the northeast Gulf Coast vicinity. Still, even it suggests low-level flow should both decrease and become veered through the day, where rich low-level moisture exists. Instability appears likely to be meager and overall severe potential appears low. The next broad mid/upper trough should progress into the West by D5/Friday. Guidance appears to be coalescing towards two distinct shortwave impulses evolving within this longwave pattern. The lead one is progged to track northeast into the northern Great Plains and then pivot east across the Upper Midwest/south-central Canada over the weekend. Meanwhile, a basal shortwave impulse should become established off the southern CA coast. This may gradually move east over the Desert Southwest and northwest Mexico late in the period. Guidance continues to differ with the degree of continental airmass intrusion into the northern Gulf, in the wake of the shortwave trough departing the East on D4. Overall trends and likelihood of surface ridging persisting across parts of the Gulf Coast suggest that returning moisture will probably be of low quality in advance of the north-central states wave. However, this may yield multiple days of return flow and an increasingly moist warm sector becoming established over the southern Great Plains by D8/Monday. SPC GEFS-based ML guidance has trended down to a 2 percent probability for D6/Saturday, after depicting a 15 percent area yesterday. It has instead, increased probabilities to 15 percent on D7/Sunday. Meanwhile, NSSL GEFS-based ML guidance has decreased probabilities for D7 from 10 percent yesterday to 5 percent today. Both of these are 5 percent or less on D8, when the ECMWF ensemble mean would be more indicative of 15 percent potential. Given the lack of consistency, a severe weather highlight for D7 or D8 appears premature but bears watching in later cycles. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0356 AM CST Mon Nov 11 2024 Valid 141200Z - 191200Z ...DISCUSSION... A shortwave trough should exit the Lower to Mid-Atlantic Coast on D4/Thursday, with amplification discrepancies from D3 persisting. The 00Z ECMWF appears to be the remaining holdout of the deterministic guidance for a low-probability severe threat in the northeast Gulf Coast vicinity. Still, even it suggests low-level flow should both decrease and become veered through the day, where rich low-level moisture exists. Instability appears likely to be meager and overall severe potential appears low. The next broad mid/upper trough should progress into the West by D5/Friday. Guidance appears to be coalescing towards two distinct shortwave impulses evolving within this longwave pattern. The lead one is progged to track northeast into the northern Great Plains and then pivot east across the Upper Midwest/south-central Canada over the weekend. Meanwhile, a basal shortwave impulse should become established off the southern CA coast. This may gradually move east over the Desert Southwest and northwest Mexico late in the period. Guidance continues to differ with the degree of continental airmass intrusion into the northern Gulf, in the wake of the shortwave trough departing the East on D4. Overall trends and likelihood of surface ridging persisting across parts of the Gulf Coast suggest that returning moisture will probably be of low quality in advance of the north-central states wave. However, this may yield multiple days of return flow and an increasingly moist warm sector becoming established over the southern Great Plains by D8/Monday. SPC GEFS-based ML guidance has trended down to a 2 percent probability for D6/Saturday, after depicting a 15 percent area yesterday. It has instead, increased probabilities to 15 percent on D7/Sunday. Meanwhile, NSSL GEFS-based ML guidance has decreased probabilities for D7 from 10 percent yesterday to 5 percent today. Both of these are 5 percent or less on D8, when the ECMWF ensemble mean would be more indicative of 15 percent potential. Given the lack of consistency, a severe weather highlight for D7 or D8 appears premature but bears watching in later cycles. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0356 AM CST Mon Nov 11 2024 Valid 141200Z - 191200Z ...DISCUSSION... A shortwave trough should exit the Lower to Mid-Atlantic Coast on D4/Thursday, with amplification discrepancies from D3 persisting. The 00Z ECMWF appears to be the remaining holdout of the deterministic guidance for a low-probability severe threat in the northeast Gulf Coast vicinity. Still, even it suggests low-level flow should both decrease and become veered through the day, where rich low-level moisture exists. Instability appears likely to be meager and overall severe potential appears low. The next broad mid/upper trough should progress into the West by D5/Friday. Guidance appears to be coalescing towards two distinct shortwave impulses evolving within this longwave pattern. The lead one is progged to track northeast into the northern Great Plains and then pivot east across the Upper Midwest/south-central Canada over the weekend. Meanwhile, a basal shortwave impulse should become established off the southern CA coast. This may gradually move east over the Desert Southwest and northwest Mexico late in the period. Guidance continues to differ with the degree of continental airmass intrusion into the northern Gulf, in the wake of the shortwave trough departing the East on D4. Overall trends and likelihood of surface ridging persisting across parts of the Gulf Coast suggest that returning moisture will probably be of low quality in advance of the north-central states wave. However, this may yield multiple days of return flow and an increasingly moist warm sector becoming established over the southern Great Plains by D8/Monday. SPC GEFS-based ML guidance has trended down to a 2 percent probability for D6/Saturday, after depicting a 15 percent area yesterday. It has instead, increased probabilities to 15 percent on D7/Sunday. Meanwhile, NSSL GEFS-based ML guidance has decreased probabilities for D7 from 10 percent yesterday to 5 percent today. Both of these are 5 percent or less on D8, when the ECMWF ensemble mean would be more indicative of 15 percent potential. Given the lack of consistency, a severe weather highlight for D7 or D8 appears premature but bears watching in later cycles. Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 AM CST Mon Nov 11 2024 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN EASTERN LA/FAR SOUTHWEST AL TO CENTRAL MS... ...SUMMARY... A marginal tornado/wind threat is apparent on Wednesday afternoon into Wednesday night across a part of the central Gulf Coast States. ...LA/MS/AL... A broad mid/upper trough over the Great Plains on Wednesday morning will progress east across the MS Valley, likely extending from the Upper Great Lakes to at least the Mid-South/TN Valley by 12Z Thursday. Models indicate spread in just how amplified the trough will be. This would correspondingly impact the southern extent of low-level flow enhancement in the Deep South to central Gulf Coast. The weak cold front that intrudes on the central Gulf Coast D1 will stall and then advance north as a warm front late D2 into D3. Rich tropical moisture, characterized by mean-mixing ratios of 15-16 g/kg, will be present to the south of this boundary, yielding potential for modest buoyancy on Wednesday afternoon. Prior to that, extensive elevated convection is expected north of the front within the warm conveyor, slowing the north-northeast advance of the front. The spread in how far south stronger low-level flow will overlap the front/warm sector, lowers confidence in the overall forecast. Conditionally, there will be potential for the rich boundary-layer moisture to overlap moderate low-level SRH amid a veering wind profile with height. Still, strong mid/upper flow will likely be confined farther north-northwest, suggesting that sustained supercell structures should struggle. Transient low-level rotation near the outflow-modulated front is seemingly the most likely scenario, which would offer a low-probability tornado/wind threat. ..Grams.. 11/11/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 AM CST Mon Nov 11 2024 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN EASTERN LA/FAR SOUTHWEST AL TO CENTRAL MS... ...SUMMARY... A marginal tornado/wind threat is apparent on Wednesday afternoon into Wednesday night across a part of the central Gulf Coast States. ...LA/MS/AL... A broad mid/upper trough over the Great Plains on Wednesday morning will progress east across the MS Valley, likely extending from the Upper Great Lakes to at least the Mid-South/TN Valley by 12Z Thursday. Models indicate spread in just how amplified the trough will be. This would correspondingly impact the southern extent of low-level flow enhancement in the Deep South to central Gulf Coast. The weak cold front that intrudes on the central Gulf Coast D1 will stall and then advance north as a warm front late D2 into D3. Rich tropical moisture, characterized by mean-mixing ratios of 15-16 g/kg, will be present to the south of this boundary, yielding potential for modest buoyancy on Wednesday afternoon. Prior to that, extensive elevated convection is expected north of the front within the warm conveyor, slowing the north-northeast advance of the front. The spread in how far south stronger low-level flow will overlap the front/warm sector, lowers confidence in the overall forecast. Conditionally, there will be potential for the rich boundary-layer moisture to overlap moderate low-level SRH amid a veering wind profile with height. Still, strong mid/upper flow will likely be confined farther north-northwest, suggesting that sustained supercell structures should struggle. Transient low-level rotation near the outflow-modulated front is seemingly the most likely scenario, which would offer a low-probability tornado/wind threat. ..Grams.. 11/11/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 AM CST Mon Nov 11 2024 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN EASTERN LA/FAR SOUTHWEST AL TO CENTRAL MS... ...SUMMARY... A marginal tornado/wind threat is apparent on Wednesday afternoon into Wednesday night across a part of the central Gulf Coast States. ...LA/MS/AL... A broad mid/upper trough over the Great Plains on Wednesday morning will progress east across the MS Valley, likely extending from the Upper Great Lakes to at least the Mid-South/TN Valley by 12Z Thursday. Models indicate spread in just how amplified the trough will be. This would correspondingly impact the southern extent of low-level flow enhancement in the Deep South to central Gulf Coast. The weak cold front that intrudes on the central Gulf Coast D1 will stall and then advance north as a warm front late D2 into D3. Rich tropical moisture, characterized by mean-mixing ratios of 15-16 g/kg, will be present to the south of this boundary, yielding potential for modest buoyancy on Wednesday afternoon. Prior to that, extensive elevated convection is expected north of the front within the warm conveyor, slowing the north-northeast advance of the front. The spread in how far south stronger low-level flow will overlap the front/warm sector, lowers confidence in the overall forecast. Conditionally, there will be potential for the rich boundary-layer moisture to overlap moderate low-level SRH amid a veering wind profile with height. Still, strong mid/upper flow will likely be confined farther north-northwest, suggesting that sustained supercell structures should struggle. Transient low-level rotation near the outflow-modulated front is seemingly the most likely scenario, which would offer a low-probability tornado/wind threat. ..Grams.. 11/11/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 AM CST Mon Nov 11 2024 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN EASTERN LA/FAR SOUTHWEST AL TO CENTRAL MS... ...SUMMARY... A marginal tornado/wind threat is apparent on Wednesday afternoon into Wednesday night across a part of the central Gulf Coast States. ...LA/MS/AL... A broad mid/upper trough over the Great Plains on Wednesday morning will progress east across the MS Valley, likely extending from the Upper Great Lakes to at least the Mid-South/TN Valley by 12Z Thursday. Models indicate spread in just how amplified the trough will be. This would correspondingly impact the southern extent of low-level flow enhancement in the Deep South to central Gulf Coast. The weak cold front that intrudes on the central Gulf Coast D1 will stall and then advance north as a warm front late D2 into D3. Rich tropical moisture, characterized by mean-mixing ratios of 15-16 g/kg, will be present to the south of this boundary, yielding potential for modest buoyancy on Wednesday afternoon. Prior to that, extensive elevated convection is expected north of the front within the warm conveyor, slowing the north-northeast advance of the front. The spread in how far south stronger low-level flow will overlap the front/warm sector, lowers confidence in the overall forecast. Conditionally, there will be potential for the rich boundary-layer moisture to overlap moderate low-level SRH amid a veering wind profile with height. Still, strong mid/upper flow will likely be confined farther north-northwest, suggesting that sustained supercell structures should struggle. Transient low-level rotation near the outflow-modulated front is seemingly the most likely scenario, which would offer a low-probability tornado/wind threat. ..Grams.. 11/11/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 AM CST Mon Nov 11 2024 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN EASTERN LA/FAR SOUTHWEST AL TO CENTRAL MS... ...SUMMARY... A marginal tornado/wind threat is apparent on Wednesday afternoon into Wednesday night across a part of the central Gulf Coast States. ...LA/MS/AL... A broad mid/upper trough over the Great Plains on Wednesday morning will progress east across the MS Valley, likely extending from the Upper Great Lakes to at least the Mid-South/TN Valley by 12Z Thursday. Models indicate spread in just how amplified the trough will be. This would correspondingly impact the southern extent of low-level flow enhancement in the Deep South to central Gulf Coast. The weak cold front that intrudes on the central Gulf Coast D1 will stall and then advance north as a warm front late D2 into D3. Rich tropical moisture, characterized by mean-mixing ratios of 15-16 g/kg, will be present to the south of this boundary, yielding potential for modest buoyancy on Wednesday afternoon. Prior to that, extensive elevated convection is expected north of the front within the warm conveyor, slowing the north-northeast advance of the front. The spread in how far south stronger low-level flow will overlap the front/warm sector, lowers confidence in the overall forecast. Conditionally, there will be potential for the rich boundary-layer moisture to overlap moderate low-level SRH amid a veering wind profile with height. Still, strong mid/upper flow will likely be confined farther north-northwest, suggesting that sustained supercell structures should struggle. Transient low-level rotation near the outflow-modulated front is seemingly the most likely scenario, which would offer a low-probability tornado/wind threat. ..Grams.. 11/11/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 AM CST Mon Nov 11 2024 Valid 131200Z - 141200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN EASTERN LA/FAR SOUTHWEST AL TO CENTRAL MS... ...SUMMARY... A marginal tornado/wind threat is apparent on Wednesday afternoon into Wednesday night across a part of the central Gulf Coast States. ...LA/MS/AL... A broad mid/upper trough over the Great Plains on Wednesday morning will progress east across the MS Valley, likely extending from the Upper Great Lakes to at least the Mid-South/TN Valley by 12Z Thursday. Models indicate spread in just how amplified the trough will be. This would correspondingly impact the southern extent of low-level flow enhancement in the Deep South to central Gulf Coast. The weak cold front that intrudes on the central Gulf Coast D1 will stall and then advance north as a warm front late D2 into D3. Rich tropical moisture, characterized by mean-mixing ratios of 15-16 g/kg, will be present to the south of this boundary, yielding potential for modest buoyancy on Wednesday afternoon. Prior to that, extensive elevated convection is expected north of the front within the warm conveyor, slowing the north-northeast advance of the front. The spread in how far south stronger low-level flow will overlap the front/warm sector, lowers confidence in the overall forecast. Conditionally, there will be potential for the rich boundary-layer moisture to overlap moderate low-level SRH amid a veering wind profile with height. Still, strong mid/upper flow will likely be confined farther north-northwest, suggesting that sustained supercell structures should struggle. Transient low-level rotation near the outflow-modulated front is seemingly the most likely scenario, which would offer a low-probability tornado/wind threat. ..Grams.. 11/11/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1242 AM CST Mon Nov 11 2024 Valid 121200Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM NORTHWEST TX TO FAR SOUTHWEST KS... ...SUMMARY... Isolated severe hail will be possible in parts of the southern High/Rolling Plains on Tuesday evening. ...Southern High/Rolling Plains... Zonal upper flow over the southern states will buckle as a full-latitude trough progresses eastward across the West. This trough should reach the Great Plains by 12Z Wednesday. Primary embedded shortwave impulse is expected to eject from the Four Corners into the central Great Plains. Low-level moisture quality downstream will be lacking, owing in part to the preceding presence of post-TC Rafael in the western Gulf. Modified moisture return will still emanate northward from northeast Mexico. Low to mid 50s surface dew points should reach the TX Panhandle by 00Z, with upper 50s farther south in west TX. This should yield a narrow ribbon of weak buoyancy (MLCAPE around 500 J/kg), ahead of a sharpening surface trough. Confidence remains low in whether surface-based storms will become sustained prior to sunset, given the limited buoyancy and rather dry mid-levels within the southwesterly flow regime. More probable convective development is expected during the evening, as large-scale ascent increases with approach of the trough and strengthening low-level warm theta-e advection occurs. Favorable speed shear in the cloud-bearing layer will support potential for a few elevated supercells. Mid-level lapse rates appear modest, and this may hold hail magnitudes to marginally severe. The severe threat will probably be confined to the early/western portion of sustained-storm activity, but small hail may persist east-northeastward in parts of OK/KS Tuesday night. ..Grams.. 11/11/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1242 AM CST Mon Nov 11 2024 Valid 121200Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM NORTHWEST TX TO FAR SOUTHWEST KS... ...SUMMARY... Isolated severe hail will be possible in parts of the southern High/Rolling Plains on Tuesday evening. ...Southern High/Rolling Plains... Zonal upper flow over the southern states will buckle as a full-latitude trough progresses eastward across the West. This trough should reach the Great Plains by 12Z Wednesday. Primary embedded shortwave impulse is expected to eject from the Four Corners into the central Great Plains. Low-level moisture quality downstream will be lacking, owing in part to the preceding presence of post-TC Rafael in the western Gulf. Modified moisture return will still emanate northward from northeast Mexico. Low to mid 50s surface dew points should reach the TX Panhandle by 00Z, with upper 50s farther south in west TX. This should yield a narrow ribbon of weak buoyancy (MLCAPE around 500 J/kg), ahead of a sharpening surface trough. Confidence remains low in whether surface-based storms will become sustained prior to sunset, given the limited buoyancy and rather dry mid-levels within the southwesterly flow regime. More probable convective development is expected during the evening, as large-scale ascent increases with approach of the trough and strengthening low-level warm theta-e advection occurs. Favorable speed shear in the cloud-bearing layer will support potential for a few elevated supercells. Mid-level lapse rates appear modest, and this may hold hail magnitudes to marginally severe. The severe threat will probably be confined to the early/western portion of sustained-storm activity, but small hail may persist east-northeastward in parts of OK/KS Tuesday night. ..Grams.. 11/11/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1242 AM CST Mon Nov 11 2024 Valid 121200Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM NORTHWEST TX TO FAR SOUTHWEST KS... ...SUMMARY... Isolated severe hail will be possible in parts of the southern High/Rolling Plains on Tuesday evening. ...Southern High/Rolling Plains... Zonal upper flow over the southern states will buckle as a full-latitude trough progresses eastward across the West. This trough should reach the Great Plains by 12Z Wednesday. Primary embedded shortwave impulse is expected to eject from the Four Corners into the central Great Plains. Low-level moisture quality downstream will be lacking, owing in part to the preceding presence of post-TC Rafael in the western Gulf. Modified moisture return will still emanate northward from northeast Mexico. Low to mid 50s surface dew points should reach the TX Panhandle by 00Z, with upper 50s farther south in west TX. This should yield a narrow ribbon of weak buoyancy (MLCAPE around 500 J/kg), ahead of a sharpening surface trough. Confidence remains low in whether surface-based storms will become sustained prior to sunset, given the limited buoyancy and rather dry mid-levels within the southwesterly flow regime. More probable convective development is expected during the evening, as large-scale ascent increases with approach of the trough and strengthening low-level warm theta-e advection occurs. Favorable speed shear in the cloud-bearing layer will support potential for a few elevated supercells. Mid-level lapse rates appear modest, and this may hold hail magnitudes to marginally severe. The severe threat will probably be confined to the early/western portion of sustained-storm activity, but small hail may persist east-northeastward in parts of OK/KS Tuesday night. ..Grams.. 11/11/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1242 AM CST Mon Nov 11 2024 Valid 121200Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM NORTHWEST TX TO FAR SOUTHWEST KS... ...SUMMARY... Isolated severe hail will be possible in parts of the southern High/Rolling Plains on Tuesday evening. ...Southern High/Rolling Plains... Zonal upper flow over the southern states will buckle as a full-latitude trough progresses eastward across the West. This trough should reach the Great Plains by 12Z Wednesday. Primary embedded shortwave impulse is expected to eject from the Four Corners into the central Great Plains. Low-level moisture quality downstream will be lacking, owing in part to the preceding presence of post-TC Rafael in the western Gulf. Modified moisture return will still emanate northward from northeast Mexico. Low to mid 50s surface dew points should reach the TX Panhandle by 00Z, with upper 50s farther south in west TX. This should yield a narrow ribbon of weak buoyancy (MLCAPE around 500 J/kg), ahead of a sharpening surface trough. Confidence remains low in whether surface-based storms will become sustained prior to sunset, given the limited buoyancy and rather dry mid-levels within the southwesterly flow regime. More probable convective development is expected during the evening, as large-scale ascent increases with approach of the trough and strengthening low-level warm theta-e advection occurs. Favorable speed shear in the cloud-bearing layer will support potential for a few elevated supercells. Mid-level lapse rates appear modest, and this may hold hail magnitudes to marginally severe. The severe threat will probably be confined to the early/western portion of sustained-storm activity, but small hail may persist east-northeastward in parts of OK/KS Tuesday night. ..Grams.. 11/11/2024 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1242 AM CST Mon Nov 11 2024 Valid 121200Z - 131200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM NORTHWEST TX TO FAR SOUTHWEST KS... ...SUMMARY... Isolated severe hail will be possible in parts of the southern High/Rolling Plains on Tuesday evening. ...Southern High/Rolling Plains... Zonal upper flow over the southern states will buckle as a full-latitude trough progresses eastward across the West. This trough should reach the Great Plains by 12Z Wednesday. Primary embedded shortwave impulse is expected to eject from the Four Corners into the central Great Plains. Low-level moisture quality downstream will be lacking, owing in part to the preceding presence of post-TC Rafael in the western Gulf. Modified moisture return will still emanate northward from northeast Mexico. Low to mid 50s surface dew points should reach the TX Panhandle by 00Z, with upper 50s farther south in west TX. This should yield a narrow ribbon of weak buoyancy (MLCAPE around 500 J/kg), ahead of a sharpening surface trough. Confidence remains low in whether surface-based storms will become sustained prior to sunset, given the limited buoyancy and rather dry mid-levels within the southwesterly flow regime. More probable convective development is expected during the evening, as large-scale ascent increases with approach of the trough and strengthening low-level warm theta-e advection occurs. Favorable speed shear in the cloud-bearing layer will support potential for a few elevated supercells. Mid-level lapse rates appear modest, and this may hold hail magnitudes to marginally severe. The severe threat will probably be confined to the early/western portion of sustained-storm activity, but small hail may persist east-northeastward in parts of OK/KS Tuesday night. ..Grams.. 11/11/2024 Read more