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SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0637 AM CST Tue Jan 16 2024 Valid 161300Z - 171200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN CENTRAL FLORIDA... ...SUMMARY... A couple brief tornadoes and isolated damaging winds are possible this morning into the afternoon over parts of the Florida Peninsula. ...Synopsis... Broadly cyclonic flow in mid/upper levels will be maintained over most of the CONUS, as a large cyclone meanders over the southern Hudson Bay/northern ON region. A basal shortwave trough was apparent in moisture-channel imagery from Lower MI across southern IL to the KS/OK border vicinity. By 00Z, this perturbation is expected to elongate further and pivot to northern NY, PA, WV, parts of KY/TN, and AR. By 12Z tomorrow, the trough should be over or just offshore of the coast from New England to northeastern NC, arching inland to the TRI area. At the surface, 11Z analysis showed two primary fronts: 1. A warm to quasistationary boundary extended from a low near Cape San Blas southeastward across central FL to a weak low near XMR, then northeastward approximately along the western part of the Gulf Stream past the NC Outer Banks. This boundary should drift northward over land through much of the day, potentially reaching north-central FL before being overtaken by the next front. 2. An Arctic cold front was drawn from the San Blas low northeastward to another low between HKY-AVL, and southwestward across the central Gulf. This front will move offshore of all the Atlantic Coast by 00Z, except central FL. By 12Z, the cold front should clear the entire FL Peninsula and Keys. ...FL Peninsula... Widely scattered to scattered thunderstorms are expected to move roughly eastward across the area, both from the Gulf on either side of the southern front, and from development over land along and south of that boundary. Isolated damaging to severe gusts are possible -- mainly near and south of the southern front where surface-based inflow is expected. A tornado also may occur in the same regime -- especially closer to the Atlantic Coast where more potential exists for storm-scale interaction with sea-breeze and/or favorably aligned outflow boundaries. For this outlook cycle, unconditional severe probability bins overall are kept at marginal categorical level, but appear nonuniform within that. Overall, they would appear somewhat greater to the east and lower to the west, if continuous/heatmap-style coloring were available. Activity over the central and especially eastern parts of the peninsula -- along and south of the southern then combined front -- will have access to a richly moist boundary layer with the longest time frame for diurnal destabilization of the inflow layer. Somewhat muted diabatic heating through cloud cover will slow the pace of destabilization, but still yield favorably uninhibited buoyancy. With surface dewpoints in the upper 60s to low 70s F, that heating should offset weak low/middle-level lapse rates enough to yield MLCAPE generally in the 1000-1500 J/kg range. With little change in either heights or height gradient aloft, mid/ upper-level winds and deep shear should remain favorable through the day, albeit with some decrease as winds veer near the surface. Supercell and bowing/clustered modes are possible within the band(s) of convection. However, the veering will lead to gradual shrinking/ straightening of hodographs during the period of daytime destabilization (offsetting factors). This will make tornado potential conditional on more storm- to local-scale effects. Activity should weaken with southward extent this evening as the combined boundary moves into a nocturnally stabilizing airmass, with still more veering of near-surface flow. ..Edwards/Dean.. 01/16/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0637 AM CST Tue Jan 16 2024 Valid 161300Z - 171200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN CENTRAL FLORIDA... ...SUMMARY... A couple brief tornadoes and isolated damaging winds are possible this morning into the afternoon over parts of the Florida Peninsula. ...Synopsis... Broadly cyclonic flow in mid/upper levels will be maintained over most of the CONUS, as a large cyclone meanders over the southern Hudson Bay/northern ON region. A basal shortwave trough was apparent in moisture-channel imagery from Lower MI across southern IL to the KS/OK border vicinity. By 00Z, this perturbation is expected to elongate further and pivot to northern NY, PA, WV, parts of KY/TN, and AR. By 12Z tomorrow, the trough should be over or just offshore of the coast from New England to northeastern NC, arching inland to the TRI area. At the surface, 11Z analysis showed two primary fronts: 1. A warm to quasistationary boundary extended from a low near Cape San Blas southeastward across central FL to a weak low near XMR, then northeastward approximately along the western part of the Gulf Stream past the NC Outer Banks. This boundary should drift northward over land through much of the day, potentially reaching north-central FL before being overtaken by the next front. 2. An Arctic cold front was drawn from the San Blas low northeastward to another low between HKY-AVL, and southwestward across the central Gulf. This front will move offshore of all the Atlantic Coast by 00Z, except central FL. By 12Z, the cold front should clear the entire FL Peninsula and Keys. ...FL Peninsula... Widely scattered to scattered thunderstorms are expected to move roughly eastward across the area, both from the Gulf on either side of the southern front, and from development over land along and south of that boundary. Isolated damaging to severe gusts are possible -- mainly near and south of the southern front where surface-based inflow is expected. A tornado also may occur in the same regime -- especially closer to the Atlantic Coast where more potential exists for storm-scale interaction with sea-breeze and/or favorably aligned outflow boundaries. For this outlook cycle, unconditional severe probability bins overall are kept at marginal categorical level, but appear nonuniform within that. Overall, they would appear somewhat greater to the east and lower to the west, if continuous/heatmap-style coloring were available. Activity over the central and especially eastern parts of the peninsula -- along and south of the southern then combined front -- will have access to a richly moist boundary layer with the longest time frame for diurnal destabilization of the inflow layer. Somewhat muted diabatic heating through cloud cover will slow the pace of destabilization, but still yield favorably uninhibited buoyancy. With surface dewpoints in the upper 60s to low 70s F, that heating should offset weak low/middle-level lapse rates enough to yield MLCAPE generally in the 1000-1500 J/kg range. With little change in either heights or height gradient aloft, mid/ upper-level winds and deep shear should remain favorable through the day, albeit with some decrease as winds veer near the surface. Supercell and bowing/clustered modes are possible within the band(s) of convection. However, the veering will lead to gradual shrinking/ straightening of hodographs during the period of daytime destabilization (offsetting factors). This will make tornado potential conditional on more storm- to local-scale effects. Activity should weaken with southward extent this evening as the combined boundary moves into a nocturnally stabilizing airmass, with still more veering of near-surface flow. ..Edwards/Dean.. 01/16/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0637 AM CST Tue Jan 16 2024 Valid 161300Z - 171200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN CENTRAL FLORIDA... ...SUMMARY... A couple brief tornadoes and isolated damaging winds are possible this morning into the afternoon over parts of the Florida Peninsula. ...Synopsis... Broadly cyclonic flow in mid/upper levels will be maintained over most of the CONUS, as a large cyclone meanders over the southern Hudson Bay/northern ON region. A basal shortwave trough was apparent in moisture-channel imagery from Lower MI across southern IL to the KS/OK border vicinity. By 00Z, this perturbation is expected to elongate further and pivot to northern NY, PA, WV, parts of KY/TN, and AR. By 12Z tomorrow, the trough should be over or just offshore of the coast from New England to northeastern NC, arching inland to the TRI area. At the surface, 11Z analysis showed two primary fronts: 1. A warm to quasistationary boundary extended from a low near Cape San Blas southeastward across central FL to a weak low near XMR, then northeastward approximately along the western part of the Gulf Stream past the NC Outer Banks. This boundary should drift northward over land through much of the day, potentially reaching north-central FL before being overtaken by the next front. 2. An Arctic cold front was drawn from the San Blas low northeastward to another low between HKY-AVL, and southwestward across the central Gulf. This front will move offshore of all the Atlantic Coast by 00Z, except central FL. By 12Z, the cold front should clear the entire FL Peninsula and Keys. ...FL Peninsula... Widely scattered to scattered thunderstorms are expected to move roughly eastward across the area, both from the Gulf on either side of the southern front, and from development over land along and south of that boundary. Isolated damaging to severe gusts are possible -- mainly near and south of the southern front where surface-based inflow is expected. A tornado also may occur in the same regime -- especially closer to the Atlantic Coast where more potential exists for storm-scale interaction with sea-breeze and/or favorably aligned outflow boundaries. For this outlook cycle, unconditional severe probability bins overall are kept at marginal categorical level, but appear nonuniform within that. Overall, they would appear somewhat greater to the east and lower to the west, if continuous/heatmap-style coloring were available. Activity over the central and especially eastern parts of the peninsula -- along and south of the southern then combined front -- will have access to a richly moist boundary layer with the longest time frame for diurnal destabilization of the inflow layer. Somewhat muted diabatic heating through cloud cover will slow the pace of destabilization, but still yield favorably uninhibited buoyancy. With surface dewpoints in the upper 60s to low 70s F, that heating should offset weak low/middle-level lapse rates enough to yield MLCAPE generally in the 1000-1500 J/kg range. With little change in either heights or height gradient aloft, mid/ upper-level winds and deep shear should remain favorable through the day, albeit with some decrease as winds veer near the surface. Supercell and bowing/clustered modes are possible within the band(s) of convection. However, the veering will lead to gradual shrinking/ straightening of hodographs during the period of daytime destabilization (offsetting factors). This will make tornado potential conditional on more storm- to local-scale effects. Activity should weaken with southward extent this evening as the combined boundary moves into a nocturnally stabilizing airmass, with still more veering of near-surface flow. ..Edwards/Dean.. 01/16/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0637 AM CST Tue Jan 16 2024 Valid 161300Z - 171200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN CENTRAL FLORIDA... ...SUMMARY... A couple brief tornadoes and isolated damaging winds are possible this morning into the afternoon over parts of the Florida Peninsula. ...Synopsis... Broadly cyclonic flow in mid/upper levels will be maintained over most of the CONUS, as a large cyclone meanders over the southern Hudson Bay/northern ON region. A basal shortwave trough was apparent in moisture-channel imagery from Lower MI across southern IL to the KS/OK border vicinity. By 00Z, this perturbation is expected to elongate further and pivot to northern NY, PA, WV, parts of KY/TN, and AR. By 12Z tomorrow, the trough should be over or just offshore of the coast from New England to northeastern NC, arching inland to the TRI area. At the surface, 11Z analysis showed two primary fronts: 1. A warm to quasistationary boundary extended from a low near Cape San Blas southeastward across central FL to a weak low near XMR, then northeastward approximately along the western part of the Gulf Stream past the NC Outer Banks. This boundary should drift northward over land through much of the day, potentially reaching north-central FL before being overtaken by the next front. 2. An Arctic cold front was drawn from the San Blas low northeastward to another low between HKY-AVL, and southwestward across the central Gulf. This front will move offshore of all the Atlantic Coast by 00Z, except central FL. By 12Z, the cold front should clear the entire FL Peninsula and Keys. ...FL Peninsula... Widely scattered to scattered thunderstorms are expected to move roughly eastward across the area, both from the Gulf on either side of the southern front, and from development over land along and south of that boundary. Isolated damaging to severe gusts are possible -- mainly near and south of the southern front where surface-based inflow is expected. A tornado also may occur in the same regime -- especially closer to the Atlantic Coast where more potential exists for storm-scale interaction with sea-breeze and/or favorably aligned outflow boundaries. For this outlook cycle, unconditional severe probability bins overall are kept at marginal categorical level, but appear nonuniform within that. Overall, they would appear somewhat greater to the east and lower to the west, if continuous/heatmap-style coloring were available. Activity over the central and especially eastern parts of the peninsula -- along and south of the southern then combined front -- will have access to a richly moist boundary layer with the longest time frame for diurnal destabilization of the inflow layer. Somewhat muted diabatic heating through cloud cover will slow the pace of destabilization, but still yield favorably uninhibited buoyancy. With surface dewpoints in the upper 60s to low 70s F, that heating should offset weak low/middle-level lapse rates enough to yield MLCAPE generally in the 1000-1500 J/kg range. With little change in either heights or height gradient aloft, mid/ upper-level winds and deep shear should remain favorable through the day, albeit with some decrease as winds veer near the surface. Supercell and bowing/clustered modes are possible within the band(s) of convection. However, the veering will lead to gradual shrinking/ straightening of hodographs during the period of daytime destabilization (offsetting factors). This will make tornado potential conditional on more storm- to local-scale effects. Activity should weaken with southward extent this evening as the combined boundary moves into a nocturnally stabilizing airmass, with still more veering of near-surface flow. ..Edwards/Dean.. 01/16/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0637 AM CST Tue Jan 16 2024 Valid 161300Z - 171200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN CENTRAL FLORIDA... ...SUMMARY... A couple brief tornadoes and isolated damaging winds are possible this morning into the afternoon over parts of the Florida Peninsula. ...Synopsis... Broadly cyclonic flow in mid/upper levels will be maintained over most of the CONUS, as a large cyclone meanders over the southern Hudson Bay/northern ON region. A basal shortwave trough was apparent in moisture-channel imagery from Lower MI across southern IL to the KS/OK border vicinity. By 00Z, this perturbation is expected to elongate further and pivot to northern NY, PA, WV, parts of KY/TN, and AR. By 12Z tomorrow, the trough should be over or just offshore of the coast from New England to northeastern NC, arching inland to the TRI area. At the surface, 11Z analysis showed two primary fronts: 1. A warm to quasistationary boundary extended from a low near Cape San Blas southeastward across central FL to a weak low near XMR, then northeastward approximately along the western part of the Gulf Stream past the NC Outer Banks. This boundary should drift northward over land through much of the day, potentially reaching north-central FL before being overtaken by the next front. 2. An Arctic cold front was drawn from the San Blas low northeastward to another low between HKY-AVL, and southwestward across the central Gulf. This front will move offshore of all the Atlantic Coast by 00Z, except central FL. By 12Z, the cold front should clear the entire FL Peninsula and Keys. ...FL Peninsula... Widely scattered to scattered thunderstorms are expected to move roughly eastward across the area, both from the Gulf on either side of the southern front, and from development over land along and south of that boundary. Isolated damaging to severe gusts are possible -- mainly near and south of the southern front where surface-based inflow is expected. A tornado also may occur in the same regime -- especially closer to the Atlantic Coast where more potential exists for storm-scale interaction with sea-breeze and/or favorably aligned outflow boundaries. For this outlook cycle, unconditional severe probability bins overall are kept at marginal categorical level, but appear nonuniform within that. Overall, they would appear somewhat greater to the east and lower to the west, if continuous/heatmap-style coloring were available. Activity over the central and especially eastern parts of the peninsula -- along and south of the southern then combined front -- will have access to a richly moist boundary layer with the longest time frame for diurnal destabilization of the inflow layer. Somewhat muted diabatic heating through cloud cover will slow the pace of destabilization, but still yield favorably uninhibited buoyancy. With surface dewpoints in the upper 60s to low 70s F, that heating should offset weak low/middle-level lapse rates enough to yield MLCAPE generally in the 1000-1500 J/kg range. With little change in either heights or height gradient aloft, mid/ upper-level winds and deep shear should remain favorable through the day, albeit with some decrease as winds veer near the surface. Supercell and bowing/clustered modes are possible within the band(s) of convection. However, the veering will lead to gradual shrinking/ straightening of hodographs during the period of daytime destabilization (offsetting factors). This will make tornado potential conditional on more storm- to local-scale effects. Activity should weaken with southward extent this evening as the combined boundary moves into a nocturnally stabilizing airmass, with still more veering of near-surface flow. ..Edwards/Dean.. 01/16/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0637 AM CST Tue Jan 16 2024 Valid 161300Z - 171200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN CENTRAL FLORIDA... ...SUMMARY... A couple brief tornadoes and isolated damaging winds are possible this morning into the afternoon over parts of the Florida Peninsula. ...Synopsis... Broadly cyclonic flow in mid/upper levels will be maintained over most of the CONUS, as a large cyclone meanders over the southern Hudson Bay/northern ON region. A basal shortwave trough was apparent in moisture-channel imagery from Lower MI across southern IL to the KS/OK border vicinity. By 00Z, this perturbation is expected to elongate further and pivot to northern NY, PA, WV, parts of KY/TN, and AR. By 12Z tomorrow, the trough should be over or just offshore of the coast from New England to northeastern NC, arching inland to the TRI area. At the surface, 11Z analysis showed two primary fronts: 1. A warm to quasistationary boundary extended from a low near Cape San Blas southeastward across central FL to a weak low near XMR, then northeastward approximately along the western part of the Gulf Stream past the NC Outer Banks. This boundary should drift northward over land through much of the day, potentially reaching north-central FL before being overtaken by the next front. 2. An Arctic cold front was drawn from the San Blas low northeastward to another low between HKY-AVL, and southwestward across the central Gulf. This front will move offshore of all the Atlantic Coast by 00Z, except central FL. By 12Z, the cold front should clear the entire FL Peninsula and Keys. ...FL Peninsula... Widely scattered to scattered thunderstorms are expected to move roughly eastward across the area, both from the Gulf on either side of the southern front, and from development over land along and south of that boundary. Isolated damaging to severe gusts are possible -- mainly near and south of the southern front where surface-based inflow is expected. A tornado also may occur in the same regime -- especially closer to the Atlantic Coast where more potential exists for storm-scale interaction with sea-breeze and/or favorably aligned outflow boundaries. For this outlook cycle, unconditional severe probability bins overall are kept at marginal categorical level, but appear nonuniform within that. Overall, they would appear somewhat greater to the east and lower to the west, if continuous/heatmap-style coloring were available. Activity over the central and especially eastern parts of the peninsula -- along and south of the southern then combined front -- will have access to a richly moist boundary layer with the longest time frame for diurnal destabilization of the inflow layer. Somewhat muted diabatic heating through cloud cover will slow the pace of destabilization, but still yield favorably uninhibited buoyancy. With surface dewpoints in the upper 60s to low 70s F, that heating should offset weak low/middle-level lapse rates enough to yield MLCAPE generally in the 1000-1500 J/kg range. With little change in either heights or height gradient aloft, mid/ upper-level winds and deep shear should remain favorable through the day, albeit with some decrease as winds veer near the surface. Supercell and bowing/clustered modes are possible within the band(s) of convection. However, the veering will lead to gradual shrinking/ straightening of hodographs during the period of daytime destabilization (offsetting factors). This will make tornado potential conditional on more storm- to local-scale effects. Activity should weaken with southward extent this evening as the combined boundary moves into a nocturnally stabilizing airmass, with still more veering of near-surface flow. ..Edwards/Dean.. 01/16/2024 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0330 AM CST Tue Jan 16 2024 Valid 191200Z - 241200Z ...DISCUSSION... The beginning of the period will see an upper trough over the eastern states and an upper ridge over the West. The upper ridge will weaken as it slides east over the Plains on Day 5/Sat, with a lower-amplitude pattern emerging east of the Rockies through Day 6/Sun. During the latter half of the period, an upper trough is forecast to develop over the western U.S. Strong surface high pressure over the Plains on Day 4/Fri will shift east through the period, and another frontal intrusion into the Gulf of Mexico will result in a generally dry/stable airmass for much of the Day 4-8 period. As the western upper trough develops late in the period, surface lee troughing will promote southerly low-level flow over the southern Plains and some Gulf moisture return is expected. As this occurs, thunderstorm potential may increase across parts of the southern Plains around Days 7-8/Mon-Tue. Modest deep-layer flow over the region, and the upper trough remaining well west, will likely limit severe potential until perhaps just beyond Day 8/Tue. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0330 AM CST Tue Jan 16 2024 Valid 191200Z - 241200Z ...DISCUSSION... The beginning of the period will see an upper trough over the eastern states and an upper ridge over the West. The upper ridge will weaken as it slides east over the Plains on Day 5/Sat, with a lower-amplitude pattern emerging east of the Rockies through Day 6/Sun. During the latter half of the period, an upper trough is forecast to develop over the western U.S. Strong surface high pressure over the Plains on Day 4/Fri will shift east through the period, and another frontal intrusion into the Gulf of Mexico will result in a generally dry/stable airmass for much of the Day 4-8 period. As the western upper trough develops late in the period, surface lee troughing will promote southerly low-level flow over the southern Plains and some Gulf moisture return is expected. As this occurs, thunderstorm potential may increase across parts of the southern Plains around Days 7-8/Mon-Tue. Modest deep-layer flow over the region, and the upper trough remaining well west, will likely limit severe potential until perhaps just beyond Day 8/Tue. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0330 AM CST Tue Jan 16 2024 Valid 191200Z - 241200Z ...DISCUSSION... The beginning of the period will see an upper trough over the eastern states and an upper ridge over the West. The upper ridge will weaken as it slides east over the Plains on Day 5/Sat, with a lower-amplitude pattern emerging east of the Rockies through Day 6/Sun. During the latter half of the period, an upper trough is forecast to develop over the western U.S. Strong surface high pressure over the Plains on Day 4/Fri will shift east through the period, and another frontal intrusion into the Gulf of Mexico will result in a generally dry/stable airmass for much of the Day 4-8 period. As the western upper trough develops late in the period, surface lee troughing will promote southerly low-level flow over the southern Plains and some Gulf moisture return is expected. As this occurs, thunderstorm potential may increase across parts of the southern Plains around Days 7-8/Mon-Tue. Modest deep-layer flow over the region, and the upper trough remaining well west, will likely limit severe potential until perhaps just beyond Day 8/Tue. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0330 AM CST Tue Jan 16 2024 Valid 191200Z - 241200Z ...DISCUSSION... The beginning of the period will see an upper trough over the eastern states and an upper ridge over the West. The upper ridge will weaken as it slides east over the Plains on Day 5/Sat, with a lower-amplitude pattern emerging east of the Rockies through Day 6/Sun. During the latter half of the period, an upper trough is forecast to develop over the western U.S. Strong surface high pressure over the Plains on Day 4/Fri will shift east through the period, and another frontal intrusion into the Gulf of Mexico will result in a generally dry/stable airmass for much of the Day 4-8 period. As the western upper trough develops late in the period, surface lee troughing will promote southerly low-level flow over the southern Plains and some Gulf moisture return is expected. As this occurs, thunderstorm potential may increase across parts of the southern Plains around Days 7-8/Mon-Tue. Modest deep-layer flow over the region, and the upper trough remaining well west, will likely limit severe potential until perhaps just beyond Day 8/Tue. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0330 AM CST Tue Jan 16 2024 Valid 191200Z - 241200Z ...DISCUSSION... The beginning of the period will see an upper trough over the eastern states and an upper ridge over the West. The upper ridge will weaken as it slides east over the Plains on Day 5/Sat, with a lower-amplitude pattern emerging east of the Rockies through Day 6/Sun. During the latter half of the period, an upper trough is forecast to develop over the western U.S. Strong surface high pressure over the Plains on Day 4/Fri will shift east through the period, and another frontal intrusion into the Gulf of Mexico will result in a generally dry/stable airmass for much of the Day 4-8 period. As the western upper trough develops late in the period, surface lee troughing will promote southerly low-level flow over the southern Plains and some Gulf moisture return is expected. As this occurs, thunderstorm potential may increase across parts of the southern Plains around Days 7-8/Mon-Tue. Modest deep-layer flow over the region, and the upper trough remaining well west, will likely limit severe potential until perhaps just beyond Day 8/Tue. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0330 AM CST Tue Jan 16 2024 Valid 191200Z - 241200Z ...DISCUSSION... The beginning of the period will see an upper trough over the eastern states and an upper ridge over the West. The upper ridge will weaken as it slides east over the Plains on Day 5/Sat, with a lower-amplitude pattern emerging east of the Rockies through Day 6/Sun. During the latter half of the period, an upper trough is forecast to develop over the western U.S. Strong surface high pressure over the Plains on Day 4/Fri will shift east through the period, and another frontal intrusion into the Gulf of Mexico will result in a generally dry/stable airmass for much of the Day 4-8 period. As the western upper trough develops late in the period, surface lee troughing will promote southerly low-level flow over the southern Plains and some Gulf moisture return is expected. As this occurs, thunderstorm potential may increase across parts of the southern Plains around Days 7-8/Mon-Tue. Modest deep-layer flow over the region, and the upper trough remaining well west, will likely limit severe potential until perhaps just beyond Day 8/Tue. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0330 AM CST Tue Jan 16 2024 Valid 191200Z - 241200Z ...DISCUSSION... The beginning of the period will see an upper trough over the eastern states and an upper ridge over the West. The upper ridge will weaken as it slides east over the Plains on Day 5/Sat, with a lower-amplitude pattern emerging east of the Rockies through Day 6/Sun. During the latter half of the period, an upper trough is forecast to develop over the western U.S. Strong surface high pressure over the Plains on Day 4/Fri will shift east through the period, and another frontal intrusion into the Gulf of Mexico will result in a generally dry/stable airmass for much of the Day 4-8 period. As the western upper trough develops late in the period, surface lee troughing will promote southerly low-level flow over the southern Plains and some Gulf moisture return is expected. As this occurs, thunderstorm potential may increase across parts of the southern Plains around Days 7-8/Mon-Tue. Modest deep-layer flow over the region, and the upper trough remaining well west, will likely limit severe potential until perhaps just beyond Day 8/Tue. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0330 AM CST Tue Jan 16 2024 Valid 191200Z - 241200Z ...DISCUSSION... The beginning of the period will see an upper trough over the eastern states and an upper ridge over the West. The upper ridge will weaken as it slides east over the Plains on Day 5/Sat, with a lower-amplitude pattern emerging east of the Rockies through Day 6/Sun. During the latter half of the period, an upper trough is forecast to develop over the western U.S. Strong surface high pressure over the Plains on Day 4/Fri will shift east through the period, and another frontal intrusion into the Gulf of Mexico will result in a generally dry/stable airmass for much of the Day 4-8 period. As the western upper trough develops late in the period, surface lee troughing will promote southerly low-level flow over the southern Plains and some Gulf moisture return is expected. As this occurs, thunderstorm potential may increase across parts of the southern Plains around Days 7-8/Mon-Tue. Modest deep-layer flow over the region, and the upper trough remaining well west, will likely limit severe potential until perhaps just beyond Day 8/Tue. Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0149 AM CST Tue Jan 16 2024 Valid 181200Z - 191200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast on Thursday. ...Synopsis... A weak upper shortwave trough over the southern Plains vicinity will shift east toward the Carolinas on Thursday. This will result in deep-layer southwesterly flow across the central/eastern Gulf Coast vicinity. At the surface, a weak low over OK/TX will track east across the Gulf coast states, before lifting northeast across the Carolinas by Friday morning. Meanwhile, cold front attendant to the low will spread southeast across the Southeastern U.S. Southerly low-level flow ahead of the surface low will allow for modest Gulf moisture to return northward, with near 60 F dewpoints moving into southern LA/MS/AL and across FL (some higher dewpoints expected central/southern FL). Overall, better thermodynamics will remain over the Gulf, with warm midlevel temperatures and poor lapse rates limiting instability inland. Nevertheless, showers and isolated thunderstorms will be possible across parts of the FL Peninsula in a warm advection regime ahead of the approaching cold front. Severe storms are not expected. ..Leitman.. 01/16/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0149 AM CST Tue Jan 16 2024 Valid 181200Z - 191200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast on Thursday. ...Synopsis... A weak upper shortwave trough over the southern Plains vicinity will shift east toward the Carolinas on Thursday. This will result in deep-layer southwesterly flow across the central/eastern Gulf Coast vicinity. At the surface, a weak low over OK/TX will track east across the Gulf coast states, before lifting northeast across the Carolinas by Friday morning. Meanwhile, cold front attendant to the low will spread southeast across the Southeastern U.S. Southerly low-level flow ahead of the surface low will allow for modest Gulf moisture to return northward, with near 60 F dewpoints moving into southern LA/MS/AL and across FL (some higher dewpoints expected central/southern FL). Overall, better thermodynamics will remain over the Gulf, with warm midlevel temperatures and poor lapse rates limiting instability inland. Nevertheless, showers and isolated thunderstorms will be possible across parts of the FL Peninsula in a warm advection regime ahead of the approaching cold front. Severe storms are not expected. ..Leitman.. 01/16/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0149 AM CST Tue Jan 16 2024 Valid 181200Z - 191200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast on Thursday. ...Synopsis... A weak upper shortwave trough over the southern Plains vicinity will shift east toward the Carolinas on Thursday. This will result in deep-layer southwesterly flow across the central/eastern Gulf Coast vicinity. At the surface, a weak low over OK/TX will track east across the Gulf coast states, before lifting northeast across the Carolinas by Friday morning. Meanwhile, cold front attendant to the low will spread southeast across the Southeastern U.S. Southerly low-level flow ahead of the surface low will allow for modest Gulf moisture to return northward, with near 60 F dewpoints moving into southern LA/MS/AL and across FL (some higher dewpoints expected central/southern FL). Overall, better thermodynamics will remain over the Gulf, with warm midlevel temperatures and poor lapse rates limiting instability inland. Nevertheless, showers and isolated thunderstorms will be possible across parts of the FL Peninsula in a warm advection regime ahead of the approaching cold front. Severe storms are not expected. ..Leitman.. 01/16/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0149 AM CST Tue Jan 16 2024 Valid 181200Z - 191200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast on Thursday. ...Synopsis... A weak upper shortwave trough over the southern Plains vicinity will shift east toward the Carolinas on Thursday. This will result in deep-layer southwesterly flow across the central/eastern Gulf Coast vicinity. At the surface, a weak low over OK/TX will track east across the Gulf coast states, before lifting northeast across the Carolinas by Friday morning. Meanwhile, cold front attendant to the low will spread southeast across the Southeastern U.S. Southerly low-level flow ahead of the surface low will allow for modest Gulf moisture to return northward, with near 60 F dewpoints moving into southern LA/MS/AL and across FL (some higher dewpoints expected central/southern FL). Overall, better thermodynamics will remain over the Gulf, with warm midlevel temperatures and poor lapse rates limiting instability inland. Nevertheless, showers and isolated thunderstorms will be possible across parts of the FL Peninsula in a warm advection regime ahead of the approaching cold front. Severe storms are not expected. ..Leitman.. 01/16/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0149 AM CST Tue Jan 16 2024 Valid 181200Z - 191200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast on Thursday. ...Synopsis... A weak upper shortwave trough over the southern Plains vicinity will shift east toward the Carolinas on Thursday. This will result in deep-layer southwesterly flow across the central/eastern Gulf Coast vicinity. At the surface, a weak low over OK/TX will track east across the Gulf coast states, before lifting northeast across the Carolinas by Friday morning. Meanwhile, cold front attendant to the low will spread southeast across the Southeastern U.S. Southerly low-level flow ahead of the surface low will allow for modest Gulf moisture to return northward, with near 60 F dewpoints moving into southern LA/MS/AL and across FL (some higher dewpoints expected central/southern FL). Overall, better thermodynamics will remain over the Gulf, with warm midlevel temperatures and poor lapse rates limiting instability inland. Nevertheless, showers and isolated thunderstorms will be possible across parts of the FL Peninsula in a warm advection regime ahead of the approaching cold front. Severe storms are not expected. ..Leitman.. 01/16/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0149 AM CST Tue Jan 16 2024 Valid 181200Z - 191200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast on Thursday. ...Synopsis... A weak upper shortwave trough over the southern Plains vicinity will shift east toward the Carolinas on Thursday. This will result in deep-layer southwesterly flow across the central/eastern Gulf Coast vicinity. At the surface, a weak low over OK/TX will track east across the Gulf coast states, before lifting northeast across the Carolinas by Friday morning. Meanwhile, cold front attendant to the low will spread southeast across the Southeastern U.S. Southerly low-level flow ahead of the surface low will allow for modest Gulf moisture to return northward, with near 60 F dewpoints moving into southern LA/MS/AL and across FL (some higher dewpoints expected central/southern FL). Overall, better thermodynamics will remain over the Gulf, with warm midlevel temperatures and poor lapse rates limiting instability inland. Nevertheless, showers and isolated thunderstorms will be possible across parts of the FL Peninsula in a warm advection regime ahead of the approaching cold front. Severe storms are not expected. ..Leitman.. 01/16/2024 Read more