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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0122 AM CDT Thu May 16 2024 Valid 171200Z - 181200Z ...NO CRITICAL AREAS... ...Synopsis... A pronounced mid-level trough will eject into the northern Plains today, supporting strong surface lee troughing over the northern High Plains tomorrow (Friday). A widespread, strong surface wind field will develop over Wyoming and points eastward as a result. However, guidance varies considerably in terms of how low RH will drop by afternoon peak heating, with some guidance members showing RH dropping as low as 15 percent in some spots, while other members show RH staying well above 25 percent in many locales. When also considering recent rainfall that portions of the northern Plains has received in the past week, fuel receptiveness to wildfire spread should also be mediocre. Fire weather highlights have been withheld given the aforementioned uncertainties with RH and fuels. Nonetheless, localized instances of wildfire growth cannot be ruled out where dry fuel beds exist given the strong winds. ..Squitieri.. 05/16/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0122 AM CDT Thu May 16 2024 Valid 171200Z - 181200Z ...NO CRITICAL AREAS... ...Synopsis... A pronounced mid-level trough will eject into the northern Plains today, supporting strong surface lee troughing over the northern High Plains tomorrow (Friday). A widespread, strong surface wind field will develop over Wyoming and points eastward as a result. However, guidance varies considerably in terms of how low RH will drop by afternoon peak heating, with some guidance members showing RH dropping as low as 15 percent in some spots, while other members show RH staying well above 25 percent in many locales. When also considering recent rainfall that portions of the northern Plains has received in the past week, fuel receptiveness to wildfire spread should also be mediocre. Fire weather highlights have been withheld given the aforementioned uncertainties with RH and fuels. Nonetheless, localized instances of wildfire growth cannot be ruled out where dry fuel beds exist given the strong winds. ..Squitieri.. 05/16/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0122 AM CDT Thu May 16 2024 Valid 171200Z - 181200Z ...NO CRITICAL AREAS... ...Synopsis... A pronounced mid-level trough will eject into the northern Plains today, supporting strong surface lee troughing over the northern High Plains tomorrow (Friday). A widespread, strong surface wind field will develop over Wyoming and points eastward as a result. However, guidance varies considerably in terms of how low RH will drop by afternoon peak heating, with some guidance members showing RH dropping as low as 15 percent in some spots, while other members show RH staying well above 25 percent in many locales. When also considering recent rainfall that portions of the northern Plains has received in the past week, fuel receptiveness to wildfire spread should also be mediocre. Fire weather highlights have been withheld given the aforementioned uncertainties with RH and fuels. Nonetheless, localized instances of wildfire growth cannot be ruled out where dry fuel beds exist given the strong winds. ..Squitieri.. 05/16/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0122 AM CDT Thu May 16 2024 Valid 171200Z - 181200Z ...NO CRITICAL AREAS... ...Synopsis... A pronounced mid-level trough will eject into the northern Plains today, supporting strong surface lee troughing over the northern High Plains tomorrow (Friday). A widespread, strong surface wind field will develop over Wyoming and points eastward as a result. However, guidance varies considerably in terms of how low RH will drop by afternoon peak heating, with some guidance members showing RH dropping as low as 15 percent in some spots, while other members show RH staying well above 25 percent in many locales. When also considering recent rainfall that portions of the northern Plains has received in the past week, fuel receptiveness to wildfire spread should also be mediocre. Fire weather highlights have been withheld given the aforementioned uncertainties with RH and fuels. Nonetheless, localized instances of wildfire growth cannot be ruled out where dry fuel beds exist given the strong winds. ..Squitieri.. 05/16/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0122 AM CDT Thu May 16 2024 Valid 171200Z - 181200Z ...NO CRITICAL AREAS... ...Synopsis... A pronounced mid-level trough will eject into the northern Plains today, supporting strong surface lee troughing over the northern High Plains tomorrow (Friday). A widespread, strong surface wind field will develop over Wyoming and points eastward as a result. However, guidance varies considerably in terms of how low RH will drop by afternoon peak heating, with some guidance members showing RH dropping as low as 15 percent in some spots, while other members show RH staying well above 25 percent in many locales. When also considering recent rainfall that portions of the northern Plains has received in the past week, fuel receptiveness to wildfire spread should also be mediocre. Fire weather highlights have been withheld given the aforementioned uncertainties with RH and fuels. Nonetheless, localized instances of wildfire growth cannot be ruled out where dry fuel beds exist given the strong winds. ..Squitieri.. 05/16/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0122 AM CDT Thu May 16 2024 Valid 171200Z - 181200Z ...NO CRITICAL AREAS... ...Synopsis... A pronounced mid-level trough will eject into the northern Plains today, supporting strong surface lee troughing over the northern High Plains tomorrow (Friday). A widespread, strong surface wind field will develop over Wyoming and points eastward as a result. However, guidance varies considerably in terms of how low RH will drop by afternoon peak heating, with some guidance members showing RH dropping as low as 15 percent in some spots, while other members show RH staying well above 25 percent in many locales. When also considering recent rainfall that portions of the northern Plains has received in the past week, fuel receptiveness to wildfire spread should also be mediocre. Fire weather highlights have been withheld given the aforementioned uncertainties with RH and fuels. Nonetheless, localized instances of wildfire growth cannot be ruled out where dry fuel beds exist given the strong winds. ..Squitieri.. 05/16/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0121 AM CDT Thu May 16 2024 Valid 161200Z - 171200Z ...Synopsis... A mid-level trough will traverse the southern Plains as a weak surface low develops near the Rio Grande today. Behind the low, isallobaric and downslope northwesterly flow will overspread the Trans Pecos region of Texas during the afternoon. 15+ mph sustained northwesterly surface winds will coincide with 10-20 percent RH and dry fuels, warranting the continuation of Elevated highlights. ..Squitieri.. 05/16/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0121 AM CDT Thu May 16 2024 Valid 161200Z - 171200Z ...Synopsis... A mid-level trough will traverse the southern Plains as a weak surface low develops near the Rio Grande today. Behind the low, isallobaric and downslope northwesterly flow will overspread the Trans Pecos region of Texas during the afternoon. 15+ mph sustained northwesterly surface winds will coincide with 10-20 percent RH and dry fuels, warranting the continuation of Elevated highlights. ..Squitieri.. 05/16/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0121 AM CDT Thu May 16 2024 Valid 161200Z - 171200Z ...Synopsis... A mid-level trough will traverse the southern Plains as a weak surface low develops near the Rio Grande today. Behind the low, isallobaric and downslope northwesterly flow will overspread the Trans Pecos region of Texas during the afternoon. 15+ mph sustained northwesterly surface winds will coincide with 10-20 percent RH and dry fuels, warranting the continuation of Elevated highlights. ..Squitieri.. 05/16/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0121 AM CDT Thu May 16 2024 Valid 161200Z - 171200Z ...Synopsis... A mid-level trough will traverse the southern Plains as a weak surface low develops near the Rio Grande today. Behind the low, isallobaric and downslope northwesterly flow will overspread the Trans Pecos region of Texas during the afternoon. 15+ mph sustained northwesterly surface winds will coincide with 10-20 percent RH and dry fuels, warranting the continuation of Elevated highlights. ..Squitieri.. 05/16/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0121 AM CDT Thu May 16 2024 Valid 161200Z - 171200Z ...Synopsis... A mid-level trough will traverse the southern Plains as a weak surface low develops near the Rio Grande today. Behind the low, isallobaric and downslope northwesterly flow will overspread the Trans Pecos region of Texas during the afternoon. 15+ mph sustained northwesterly surface winds will coincide with 10-20 percent RH and dry fuels, warranting the continuation of Elevated highlights. ..Squitieri.. 05/16/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0121 AM CDT Thu May 16 2024 Valid 161200Z - 171200Z ...Synopsis... A mid-level trough will traverse the southern Plains as a weak surface low develops near the Rio Grande today. Behind the low, isallobaric and downslope northwesterly flow will overspread the Trans Pecos region of Texas during the afternoon. 15+ mph sustained northwesterly surface winds will coincide with 10-20 percent RH and dry fuels, warranting the continuation of Elevated highlights. ..Squitieri.. 05/16/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0121 AM CDT Thu May 16 2024 Valid 161200Z - 171200Z ...Synopsis... A mid-level trough will traverse the southern Plains as a weak surface low develops near the Rio Grande today. Behind the low, isallobaric and downslope northwesterly flow will overspread the Trans Pecos region of Texas during the afternoon. 15+ mph sustained northwesterly surface winds will coincide with 10-20 percent RH and dry fuels, warranting the continuation of Elevated highlights. ..Squitieri.. 05/16/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1259 AM CDT Thu May 16 2024 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM FAR SOUTHEAST TEXAS INTO MUCH OF LOUISIANA...CENTRAL/SOUTHERN MISSISSIPPI...AND WESTERN ALABAMA... ...SUMMARY... Severe thunderstorms are possible from far southeast Texas into much of Louisiana, central/southern Mississippi, and western Alabama on Friday. ...East/Southeast TX and Southeast OK through the Lower MS Valley and into the TN Valley/Southeast... A southern-stream shortwave trough is forecast to extend from the Lower MO Valley southwestward through central OK and Far West TX and into northeast Mexico early Friday morning. A belt of moderate to strong southwesterly flow aloft will likely extend through the base of this shortwave, from northeast Mexico through east/southeast TX and the Lower MS Valley into the TN Valley/Southeast. This belt of stronger flow will persist throughout much of the day as its parent shortwave trough shifts eastward/northeastward. Surface pattern preceding this shortwave will be significantly more uncertain, largely resulting from uncertainty related to the timing and strength of an early morning MCS forecast to move from the Lower MS Valley across the central/southern MS and AL. This MCS will likely lead an outflow boundary in its wake, which could then return northward throughout the day amid modest low-level moisture advection. This scenario is supported by much of the guidance. However, if/when any development occurs along and south of this boundary during the afternoon/evening is less clear, likely a result of poor synoptic support and predominantly mesoscale factors contributing to additional initiation. Strong buoyancy and shear suggest that any storms that do develop should quickly become severe, with large to very large hail as the primary threat. Weak low-level flow should keep the tornado threat low, but still non-zero given the likely supercell mode. Height falls should reach the Lower MS Valley late Friday night/early Saturday morning, with around round of thunderstorms likely given that earlier activity is unlikely to overturn the airmass. These storms could evolve into a convective line that would then track quickly eastward across the central Gulf Coast, with damaging gusts as the primary risk. ...Northern Plains into the Upper MS Valley... A northern-stream shortwave trough is forecast to move through the northern Rockies on Friday, reaching the northern High Plains by early Saturday morning. An attendant surface low will move eastward just ahead of the shortwave, moving across southern Saskatchewan and Manitoba. Surface lee troughing will sharpen ahead of the shortwave trough as well, with cyclogenesis anticipated across western SD by the late afternoon. A cold front will extend between these two surface lows, progressing eastward/southeastward across the Dakotas and into western MN from late Friday afternoon into early Saturday morning. Buoyancy ahead of this cold front will be modest, supported predominantly by cool mid-level temperatures atop a warm and deeply mixed boundary layer. High-based thunderstorms are expected to develop along the cold front, with strong outflow possible. Upscale growth is anticipated, as amalgamation of storm outflows occurs quickly. Strengthening westerly flow aloft will foster fast storm motion and the potential for some damaging wind gusts as the convective line moves eastward across the Dakotas. ..Mosier.. 05/16/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1259 AM CDT Thu May 16 2024 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM FAR SOUTHEAST TEXAS INTO MUCH OF LOUISIANA...CENTRAL/SOUTHERN MISSISSIPPI...AND WESTERN ALABAMA... ...SUMMARY... Severe thunderstorms are possible from far southeast Texas into much of Louisiana, central/southern Mississippi, and western Alabama on Friday. ...East/Southeast TX and Southeast OK through the Lower MS Valley and into the TN Valley/Southeast... A southern-stream shortwave trough is forecast to extend from the Lower MO Valley southwestward through central OK and Far West TX and into northeast Mexico early Friday morning. A belt of moderate to strong southwesterly flow aloft will likely extend through the base of this shortwave, from northeast Mexico through east/southeast TX and the Lower MS Valley into the TN Valley/Southeast. This belt of stronger flow will persist throughout much of the day as its parent shortwave trough shifts eastward/northeastward. Surface pattern preceding this shortwave will be significantly more uncertain, largely resulting from uncertainty related to the timing and strength of an early morning MCS forecast to move from the Lower MS Valley across the central/southern MS and AL. This MCS will likely lead an outflow boundary in its wake, which could then return northward throughout the day amid modest low-level moisture advection. This scenario is supported by much of the guidance. However, if/when any development occurs along and south of this boundary during the afternoon/evening is less clear, likely a result of poor synoptic support and predominantly mesoscale factors contributing to additional initiation. Strong buoyancy and shear suggest that any storms that do develop should quickly become severe, with large to very large hail as the primary threat. Weak low-level flow should keep the tornado threat low, but still non-zero given the likely supercell mode. Height falls should reach the Lower MS Valley late Friday night/early Saturday morning, with around round of thunderstorms likely given that earlier activity is unlikely to overturn the airmass. These storms could evolve into a convective line that would then track quickly eastward across the central Gulf Coast, with damaging gusts as the primary risk. ...Northern Plains into the Upper MS Valley... A northern-stream shortwave trough is forecast to move through the northern Rockies on Friday, reaching the northern High Plains by early Saturday morning. An attendant surface low will move eastward just ahead of the shortwave, moving across southern Saskatchewan and Manitoba. Surface lee troughing will sharpen ahead of the shortwave trough as well, with cyclogenesis anticipated across western SD by the late afternoon. A cold front will extend between these two surface lows, progressing eastward/southeastward across the Dakotas and into western MN from late Friday afternoon into early Saturday morning. Buoyancy ahead of this cold front will be modest, supported predominantly by cool mid-level temperatures atop a warm and deeply mixed boundary layer. High-based thunderstorms are expected to develop along the cold front, with strong outflow possible. Upscale growth is anticipated, as amalgamation of storm outflows occurs quickly. Strengthening westerly flow aloft will foster fast storm motion and the potential for some damaging wind gusts as the convective line moves eastward across the Dakotas. ..Mosier.. 05/16/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1259 AM CDT Thu May 16 2024 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM FAR SOUTHEAST TEXAS INTO MUCH OF LOUISIANA...CENTRAL/SOUTHERN MISSISSIPPI...AND WESTERN ALABAMA... ...SUMMARY... Severe thunderstorms are possible from far southeast Texas into much of Louisiana, central/southern Mississippi, and western Alabama on Friday. ...East/Southeast TX and Southeast OK through the Lower MS Valley and into the TN Valley/Southeast... A southern-stream shortwave trough is forecast to extend from the Lower MO Valley southwestward through central OK and Far West TX and into northeast Mexico early Friday morning. A belt of moderate to strong southwesterly flow aloft will likely extend through the base of this shortwave, from northeast Mexico through east/southeast TX and the Lower MS Valley into the TN Valley/Southeast. This belt of stronger flow will persist throughout much of the day as its parent shortwave trough shifts eastward/northeastward. Surface pattern preceding this shortwave will be significantly more uncertain, largely resulting from uncertainty related to the timing and strength of an early morning MCS forecast to move from the Lower MS Valley across the central/southern MS and AL. This MCS will likely lead an outflow boundary in its wake, which could then return northward throughout the day amid modest low-level moisture advection. This scenario is supported by much of the guidance. However, if/when any development occurs along and south of this boundary during the afternoon/evening is less clear, likely a result of poor synoptic support and predominantly mesoscale factors contributing to additional initiation. Strong buoyancy and shear suggest that any storms that do develop should quickly become severe, with large to very large hail as the primary threat. Weak low-level flow should keep the tornado threat low, but still non-zero given the likely supercell mode. Height falls should reach the Lower MS Valley late Friday night/early Saturday morning, with around round of thunderstorms likely given that earlier activity is unlikely to overturn the airmass. These storms could evolve into a convective line that would then track quickly eastward across the central Gulf Coast, with damaging gusts as the primary risk. ...Northern Plains into the Upper MS Valley... A northern-stream shortwave trough is forecast to move through the northern Rockies on Friday, reaching the northern High Plains by early Saturday morning. An attendant surface low will move eastward just ahead of the shortwave, moving across southern Saskatchewan and Manitoba. Surface lee troughing will sharpen ahead of the shortwave trough as well, with cyclogenesis anticipated across western SD by the late afternoon. A cold front will extend between these two surface lows, progressing eastward/southeastward across the Dakotas and into western MN from late Friday afternoon into early Saturday morning. Buoyancy ahead of this cold front will be modest, supported predominantly by cool mid-level temperatures atop a warm and deeply mixed boundary layer. High-based thunderstorms are expected to develop along the cold front, with strong outflow possible. Upscale growth is anticipated, as amalgamation of storm outflows occurs quickly. Strengthening westerly flow aloft will foster fast storm motion and the potential for some damaging wind gusts as the convective line moves eastward across the Dakotas. ..Mosier.. 05/16/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1259 AM CDT Thu May 16 2024 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM FAR SOUTHEAST TEXAS INTO MUCH OF LOUISIANA...CENTRAL/SOUTHERN MISSISSIPPI...AND WESTERN ALABAMA... ...SUMMARY... Severe thunderstorms are possible from far southeast Texas into much of Louisiana, central/southern Mississippi, and western Alabama on Friday. ...East/Southeast TX and Southeast OK through the Lower MS Valley and into the TN Valley/Southeast... A southern-stream shortwave trough is forecast to extend from the Lower MO Valley southwestward through central OK and Far West TX and into northeast Mexico early Friday morning. A belt of moderate to strong southwesterly flow aloft will likely extend through the base of this shortwave, from northeast Mexico through east/southeast TX and the Lower MS Valley into the TN Valley/Southeast. This belt of stronger flow will persist throughout much of the day as its parent shortwave trough shifts eastward/northeastward. Surface pattern preceding this shortwave will be significantly more uncertain, largely resulting from uncertainty related to the timing and strength of an early morning MCS forecast to move from the Lower MS Valley across the central/southern MS and AL. This MCS will likely lead an outflow boundary in its wake, which could then return northward throughout the day amid modest low-level moisture advection. This scenario is supported by much of the guidance. However, if/when any development occurs along and south of this boundary during the afternoon/evening is less clear, likely a result of poor synoptic support and predominantly mesoscale factors contributing to additional initiation. Strong buoyancy and shear suggest that any storms that do develop should quickly become severe, with large to very large hail as the primary threat. Weak low-level flow should keep the tornado threat low, but still non-zero given the likely supercell mode. Height falls should reach the Lower MS Valley late Friday night/early Saturday morning, with around round of thunderstorms likely given that earlier activity is unlikely to overturn the airmass. These storms could evolve into a convective line that would then track quickly eastward across the central Gulf Coast, with damaging gusts as the primary risk. ...Northern Plains into the Upper MS Valley... A northern-stream shortwave trough is forecast to move through the northern Rockies on Friday, reaching the northern High Plains by early Saturday morning. An attendant surface low will move eastward just ahead of the shortwave, moving across southern Saskatchewan and Manitoba. Surface lee troughing will sharpen ahead of the shortwave trough as well, with cyclogenesis anticipated across western SD by the late afternoon. A cold front will extend between these two surface lows, progressing eastward/southeastward across the Dakotas and into western MN from late Friday afternoon into early Saturday morning. Buoyancy ahead of this cold front will be modest, supported predominantly by cool mid-level temperatures atop a warm and deeply mixed boundary layer. High-based thunderstorms are expected to develop along the cold front, with strong outflow possible. Upscale growth is anticipated, as amalgamation of storm outflows occurs quickly. Strengthening westerly flow aloft will foster fast storm motion and the potential for some damaging wind gusts as the convective line moves eastward across the Dakotas. ..Mosier.. 05/16/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1259 AM CDT Thu May 16 2024 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM FAR SOUTHEAST TEXAS INTO MUCH OF LOUISIANA...CENTRAL/SOUTHERN MISSISSIPPI...AND WESTERN ALABAMA... ...SUMMARY... Severe thunderstorms are possible from far southeast Texas into much of Louisiana, central/southern Mississippi, and western Alabama on Friday. ...East/Southeast TX and Southeast OK through the Lower MS Valley and into the TN Valley/Southeast... A southern-stream shortwave trough is forecast to extend from the Lower MO Valley southwestward through central OK and Far West TX and into northeast Mexico early Friday morning. A belt of moderate to strong southwesterly flow aloft will likely extend through the base of this shortwave, from northeast Mexico through east/southeast TX and the Lower MS Valley into the TN Valley/Southeast. This belt of stronger flow will persist throughout much of the day as its parent shortwave trough shifts eastward/northeastward. Surface pattern preceding this shortwave will be significantly more uncertain, largely resulting from uncertainty related to the timing and strength of an early morning MCS forecast to move from the Lower MS Valley across the central/southern MS and AL. This MCS will likely lead an outflow boundary in its wake, which could then return northward throughout the day amid modest low-level moisture advection. This scenario is supported by much of the guidance. However, if/when any development occurs along and south of this boundary during the afternoon/evening is less clear, likely a result of poor synoptic support and predominantly mesoscale factors contributing to additional initiation. Strong buoyancy and shear suggest that any storms that do develop should quickly become severe, with large to very large hail as the primary threat. Weak low-level flow should keep the tornado threat low, but still non-zero given the likely supercell mode. Height falls should reach the Lower MS Valley late Friday night/early Saturday morning, with around round of thunderstorms likely given that earlier activity is unlikely to overturn the airmass. These storms could evolve into a convective line that would then track quickly eastward across the central Gulf Coast, with damaging gusts as the primary risk. ...Northern Plains into the Upper MS Valley... A northern-stream shortwave trough is forecast to move through the northern Rockies on Friday, reaching the northern High Plains by early Saturday morning. An attendant surface low will move eastward just ahead of the shortwave, moving across southern Saskatchewan and Manitoba. Surface lee troughing will sharpen ahead of the shortwave trough as well, with cyclogenesis anticipated across western SD by the late afternoon. A cold front will extend between these two surface lows, progressing eastward/southeastward across the Dakotas and into western MN from late Friday afternoon into early Saturday morning. Buoyancy ahead of this cold front will be modest, supported predominantly by cool mid-level temperatures atop a warm and deeply mixed boundary layer. High-based thunderstorms are expected to develop along the cold front, with strong outflow possible. Upscale growth is anticipated, as amalgamation of storm outflows occurs quickly. Strengthening westerly flow aloft will foster fast storm motion and the potential for some damaging wind gusts as the convective line moves eastward across the Dakotas. ..Mosier.. 05/16/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1259 AM CDT Thu May 16 2024 Valid 171200Z - 181200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM FAR SOUTHEAST TEXAS INTO MUCH OF LOUISIANA...CENTRAL/SOUTHERN MISSISSIPPI...AND WESTERN ALABAMA... ...SUMMARY... Severe thunderstorms are possible from far southeast Texas into much of Louisiana, central/southern Mississippi, and western Alabama on Friday. ...East/Southeast TX and Southeast OK through the Lower MS Valley and into the TN Valley/Southeast... A southern-stream shortwave trough is forecast to extend from the Lower MO Valley southwestward through central OK and Far West TX and into northeast Mexico early Friday morning. A belt of moderate to strong southwesterly flow aloft will likely extend through the base of this shortwave, from northeast Mexico through east/southeast TX and the Lower MS Valley into the TN Valley/Southeast. This belt of stronger flow will persist throughout much of the day as its parent shortwave trough shifts eastward/northeastward. Surface pattern preceding this shortwave will be significantly more uncertain, largely resulting from uncertainty related to the timing and strength of an early morning MCS forecast to move from the Lower MS Valley across the central/southern MS and AL. This MCS will likely lead an outflow boundary in its wake, which could then return northward throughout the day amid modest low-level moisture advection. This scenario is supported by much of the guidance. However, if/when any development occurs along and south of this boundary during the afternoon/evening is less clear, likely a result of poor synoptic support and predominantly mesoscale factors contributing to additional initiation. Strong buoyancy and shear suggest that any storms that do develop should quickly become severe, with large to very large hail as the primary threat. Weak low-level flow should keep the tornado threat low, but still non-zero given the likely supercell mode. Height falls should reach the Lower MS Valley late Friday night/early Saturday morning, with around round of thunderstorms likely given that earlier activity is unlikely to overturn the airmass. These storms could evolve into a convective line that would then track quickly eastward across the central Gulf Coast, with damaging gusts as the primary risk. ...Northern Plains into the Upper MS Valley... A northern-stream shortwave trough is forecast to move through the northern Rockies on Friday, reaching the northern High Plains by early Saturday morning. An attendant surface low will move eastward just ahead of the shortwave, moving across southern Saskatchewan and Manitoba. Surface lee troughing will sharpen ahead of the shortwave trough as well, with cyclogenesis anticipated across western SD by the late afternoon. A cold front will extend between these two surface lows, progressing eastward/southeastward across the Dakotas and into western MN from late Friday afternoon into early Saturday morning. Buoyancy ahead of this cold front will be modest, supported predominantly by cool mid-level temperatures atop a warm and deeply mixed boundary layer. High-based thunderstorms are expected to develop along the cold front, with strong outflow possible. Upscale growth is anticipated, as amalgamation of storm outflows occurs quickly. Strengthening westerly flow aloft will foster fast storm motion and the potential for some damaging wind gusts as the convective line moves eastward across the Dakotas. ..Mosier.. 05/16/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1247 AM CDT Thu May 16 2024 Valid 161200Z - 171200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS LATE THIS AFTERNOON AND EVENING ACROSS PARTS OF CENTRAL AND SOUTHEAST TEXAS... ...SUMMARY... Thunderstorms posing a risk for severe hail and wind may become fairly numerous across parts of central and southeastern Texas this afternoon into tonight. A couple of tornadoes are also possible, and an organized cluster of storms might eventually evolve by late evening, accompanied by a more substantive risk for damaging wind gusts. ...Synopsis... Seasonably high moisture content has generally become suppressed offshore of the southern Atlantic Seaboard through the central Gulf of Mexico and lower Rio Grande Valley, in the wake of a surface cyclone now centered offshore of the northern Mid Atlantic Coast. The cyclone is forecast to weaken and migrate away from the coast, as associated large-scale mid/upper troughing progresses east of the Atlantic Seaboard through early Friday. As this occurs, and similar magnitude mid/upper troughing (at least initially) emerges from the Southwest, low-level moisture appears likely to surge northeast of the lower Rio Grande Valley toward the lower Mississippi Valley. Models do suggest that the Southwestern trough may progress east-northeastward in somewhat piece-meal fashion, with perhaps one notable perturbation accelerating across the Permian Basin by this evening, preceded by one or two more subtle impulses. Each will tend to suppress mid/upper ridging now present across the southern Great Plains, and may be accompanied by a substantive wave of convective development. However, the details of the potential conglomerate convective evolution remain unclear, and convection allowing model output is varied. ...Texas... While the influence of early period convection and associated outflow on the low-level environment remains uncertain, model output is suggestive that a fairly well-defined lower/mid-tropospheric baroclinic zone (around 700 mb) may provide the primary focus for stronger convective development during this period. In the wake of at least one initial short wave perturbation, and in advance of the more prominent one, this will likely demarcate the northern periphery of the warmer and more strongly capping elevated mixed-layer air. By late this afternoon, it is possible that a zone of differential surface heating may become better defined beneath this regime, from portions of the Pecos and Rio Grande Valleys into central Texas. Along and south of this zone, it appears that mixed-layer CAPE will become large (on the order of 2000-4000 J/kg), beneath seasonably strong southwesterly upper flow. Deep-layer shear likely will be supportive of supercells, aided by veering with height of initially modest low-level wind fields which are forecast to strengthen by this evening across central into southeastern Texas. Large hail and locally damaging wind gusts appear the primary severe threat with initial eastward/southeastward propagating supercells by late afternoon. As low-level hodographs enlarge, the risk for a couple of tornadoes may increase by this evening in both lingering supercells and upscale growing convection. At least one prominent cluster may gradually evolve and organize across central into southeastern Texas by late this evening, accompanied by increasing potential for damaging wind gusts. ..Kerr/Squitieri.. 05/16/2024 Read more