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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0946 AM CST Mon Dec 30 2024 Valid 301700Z - 311200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF THE SOUTHERN HIGH PLAINS INTO THE BIG BEND... Minor modifications were made to the Elevated areas based on the most recent observations and high-resolution forecast guidance. Of note, locally critical conditions are likely in southeast portions of the Elevated area in the western Texas Hill Country. Otherwise, the forecast remains on track, and please see the previous discussion for more details. ..Nauslar.. 12/30/2024 .PREV DISCUSSION... /ISSUED 0122 AM CST Mon Dec 30 2024/ ...Synopsis... Enhanced westerly flow aloft will overspread the central/southern Rockies today through the base of a mid-level shortwave moving across the central/southern Plains. Surface cyclogenesis is expected with strengthening lee troughing. This pattern will lead to an increase in westerly surface winds across portions of the southern High Plains, supporting a broad region of Elevated to Critical fire weather concerns. ...Eastern New Mexico, Texas/Oklahoma Panhandle, Western Texas... Warm/dry/gusty westerly downslope flow is expected across eastern New Mexico into western Texas/Oklahoma today. Afternoon relative-humidity reductions to around 10-20 percent (driest across portions of western Texas) will overlap surface winds sustained around 20-25 mph. Fuels within this region have seen drying over the last several days. While latest fuel guidance suggests 100-hr fuels are largely marginal, the extended period of critical winds and relative humidity should lead to further drying (especially of fine fuels), supporting risk for fire spread. ...Southern California... Offshore gradients will increase today across southern California, with gusty winds (25-45 mph) across the Transverse ranges. This will overlap relative-humidity reductions to around 15-30%. An Elevated region was maintained with this outlook to cover this threat. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0614 AM CST Mon Dec 30 2024 Valid 301300Z - 311200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. ...Synopsis/Discussion... Broadly cyclonic flow will be maintained over most of the CONUS in mid/upper levels, except for progressive shortwave ridging in between these two perturbations: 1. A strong, negatively tilted shortwave trough apparent in moisture-channel imagery from a 500-mb low over Lake Huron, southeastward WV to coastal SC. This feature is expected to lose amplitude while pivoting northeastward up the East Coast and central/northern Appalachians, and across the Lower Great Lakes, through the end of the period. The associated surface cold front is offshore from the mid-Atlantic, and extends southwestward across central FL to the central Gulf, where frontal deceleration and weakening are expected through most of the period. 2. An initially weaker shortwave trough, evident from the Black Hills southward over eastern CO. This feature should strengthen today and tonight as several proximal vorticity lobes phase with each other, and ageostrophic/baroclinic forcings intensify. The trough should move east-southeastward across the central Plains and lower Missouri Valley, reaching the lower Ohio Valley and Mid-South region by 12Z tomorrow. In the wake of prior cold-frontal passage, low/middle-level moisture will be weak, yet still sufficient to support isolated, nocturnal, non-severe thunderstorms amidst a corridor of strong large-scale ascent/destabilization aloft, from the mid-Mississippi Valley to lower Ohio Valley region. ..Edwards/Grams.. 12/30/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0614 AM CST Mon Dec 30 2024 Valid 301300Z - 311200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. ...Synopsis/Discussion... Broadly cyclonic flow will be maintained over most of the CONUS in mid/upper levels, except for progressive shortwave ridging in between these two perturbations: 1. A strong, negatively tilted shortwave trough apparent in moisture-channel imagery from a 500-mb low over Lake Huron, southeastward WV to coastal SC. This feature is expected to lose amplitude while pivoting northeastward up the East Coast and central/northern Appalachians, and across the Lower Great Lakes, through the end of the period. The associated surface cold front is offshore from the mid-Atlantic, and extends southwestward across central FL to the central Gulf, where frontal deceleration and weakening are expected through most of the period. 2. An initially weaker shortwave trough, evident from the Black Hills southward over eastern CO. This feature should strengthen today and tonight as several proximal vorticity lobes phase with each other, and ageostrophic/baroclinic forcings intensify. The trough should move east-southeastward across the central Plains and lower Missouri Valley, reaching the lower Ohio Valley and Mid-South region by 12Z tomorrow. In the wake of prior cold-frontal passage, low/middle-level moisture will be weak, yet still sufficient to support isolated, nocturnal, non-severe thunderstorms amidst a corridor of strong large-scale ascent/destabilization aloft, from the mid-Mississippi Valley to lower Ohio Valley region. ..Edwards/Grams.. 12/30/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0614 AM CST Mon Dec 30 2024 Valid 301300Z - 311200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. ...Synopsis/Discussion... Broadly cyclonic flow will be maintained over most of the CONUS in mid/upper levels, except for progressive shortwave ridging in between these two perturbations: 1. A strong, negatively tilted shortwave trough apparent in moisture-channel imagery from a 500-mb low over Lake Huron, southeastward WV to coastal SC. This feature is expected to lose amplitude while pivoting northeastward up the East Coast and central/northern Appalachians, and across the Lower Great Lakes, through the end of the period. The associated surface cold front is offshore from the mid-Atlantic, and extends southwestward across central FL to the central Gulf, where frontal deceleration and weakening are expected through most of the period. 2. An initially weaker shortwave trough, evident from the Black Hills southward over eastern CO. This feature should strengthen today and tonight as several proximal vorticity lobes phase with each other, and ageostrophic/baroclinic forcings intensify. The trough should move east-southeastward across the central Plains and lower Missouri Valley, reaching the lower Ohio Valley and Mid-South region by 12Z tomorrow. In the wake of prior cold-frontal passage, low/middle-level moisture will be weak, yet still sufficient to support isolated, nocturnal, non-severe thunderstorms amidst a corridor of strong large-scale ascent/destabilization aloft, from the mid-Mississippi Valley to lower Ohio Valley region. ..Edwards/Grams.. 12/30/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0614 AM CST Mon Dec 30 2024 Valid 301300Z - 311200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. ...Synopsis/Discussion... Broadly cyclonic flow will be maintained over most of the CONUS in mid/upper levels, except for progressive shortwave ridging in between these two perturbations: 1. A strong, negatively tilted shortwave trough apparent in moisture-channel imagery from a 500-mb low over Lake Huron, southeastward WV to coastal SC. This feature is expected to lose amplitude while pivoting northeastward up the East Coast and central/northern Appalachians, and across the Lower Great Lakes, through the end of the period. The associated surface cold front is offshore from the mid-Atlantic, and extends southwestward across central FL to the central Gulf, where frontal deceleration and weakening are expected through most of the period. 2. An initially weaker shortwave trough, evident from the Black Hills southward over eastern CO. This feature should strengthen today and tonight as several proximal vorticity lobes phase with each other, and ageostrophic/baroclinic forcings intensify. The trough should move east-southeastward across the central Plains and lower Missouri Valley, reaching the lower Ohio Valley and Mid-South region by 12Z tomorrow. In the wake of prior cold-frontal passage, low/middle-level moisture will be weak, yet still sufficient to support isolated, nocturnal, non-severe thunderstorms amidst a corridor of strong large-scale ascent/destabilization aloft, from the mid-Mississippi Valley to lower Ohio Valley region. ..Edwards/Grams.. 12/30/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0614 AM CST Mon Dec 30 2024 Valid 301300Z - 311200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not expected through tonight. ...Synopsis/Discussion... Broadly cyclonic flow will be maintained over most of the CONUS in mid/upper levels, except for progressive shortwave ridging in between these two perturbations: 1. A strong, negatively tilted shortwave trough apparent in moisture-channel imagery from a 500-mb low over Lake Huron, southeastward WV to coastal SC. This feature is expected to lose amplitude while pivoting northeastward up the East Coast and central/northern Appalachians, and across the Lower Great Lakes, through the end of the period. The associated surface cold front is offshore from the mid-Atlantic, and extends southwestward across central FL to the central Gulf, where frontal deceleration and weakening are expected through most of the period. 2. An initially weaker shortwave trough, evident from the Black Hills southward over eastern CO. This feature should strengthen today and tonight as several proximal vorticity lobes phase with each other, and ageostrophic/baroclinic forcings intensify. The trough should move east-southeastward across the central Plains and lower Missouri Valley, reaching the lower Ohio Valley and Mid-South region by 12Z tomorrow. In the wake of prior cold-frontal passage, low/middle-level moisture will be weak, yet still sufficient to support isolated, nocturnal, non-severe thunderstorms amidst a corridor of strong large-scale ascent/destabilization aloft, from the mid-Mississippi Valley to lower Ohio Valley region. ..Edwards/Grams.. 12/30/2024 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0331 AM CST Mon Dec 30 2024 Valid 021200Z - 071200Z ...DISCUSSION... Thunderstorm chances will likely be limited on D4/Thursday and D5/Friday as airmass over the CONUS remains too cold and dry. Some airmass modification may begin across the southern Plains late d5/Friday or early D6/Saturday as a shortwave trough progresses across the western CONUS. As the upper pattern trends more zonal across the central CONUS, surface lee troughing will sharpen, with low-level flow forecast to strengthen amid the increasing surface pressure gradient. The approaching shortwave trough is expected to continue its eastward progression into the Plains on D6/Saturday and D7/Sunday, resulting in potential interaction with this return moisture from central/eastern portions of TX/OK into the Lower MS Valley. All aspects of the approaching shortwave trough remain uncertain, with deterministic guidance showing large run-to-run variability and notable difference between the GEFS and EPS. As such, overall forecast confidence is low. However, the overall trends suggests some severe potential may materialize late this weekend into early next week. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0331 AM CST Mon Dec 30 2024 Valid 021200Z - 071200Z ...DISCUSSION... Thunderstorm chances will likely be limited on D4/Thursday and D5/Friday as airmass over the CONUS remains too cold and dry. Some airmass modification may begin across the southern Plains late d5/Friday or early D6/Saturday as a shortwave trough progresses across the western CONUS. As the upper pattern trends more zonal across the central CONUS, surface lee troughing will sharpen, with low-level flow forecast to strengthen amid the increasing surface pressure gradient. The approaching shortwave trough is expected to continue its eastward progression into the Plains on D6/Saturday and D7/Sunday, resulting in potential interaction with this return moisture from central/eastern portions of TX/OK into the Lower MS Valley. All aspects of the approaching shortwave trough remain uncertain, with deterministic guidance showing large run-to-run variability and notable difference between the GEFS and EPS. As such, overall forecast confidence is low. However, the overall trends suggests some severe potential may materialize late this weekend into early next week. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0331 AM CST Mon Dec 30 2024 Valid 021200Z - 071200Z ...DISCUSSION... Thunderstorm chances will likely be limited on D4/Thursday and D5/Friday as airmass over the CONUS remains too cold and dry. Some airmass modification may begin across the southern Plains late d5/Friday or early D6/Saturday as a shortwave trough progresses across the western CONUS. As the upper pattern trends more zonal across the central CONUS, surface lee troughing will sharpen, with low-level flow forecast to strengthen amid the increasing surface pressure gradient. The approaching shortwave trough is expected to continue its eastward progression into the Plains on D6/Saturday and D7/Sunday, resulting in potential interaction with this return moisture from central/eastern portions of TX/OK into the Lower MS Valley. All aspects of the approaching shortwave trough remain uncertain, with deterministic guidance showing large run-to-run variability and notable difference between the GEFS and EPS. As such, overall forecast confidence is low. However, the overall trends suggests some severe potential may materialize late this weekend into early next week. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0331 AM CST Mon Dec 30 2024 Valid 021200Z - 071200Z ...DISCUSSION... Thunderstorm chances will likely be limited on D4/Thursday and D5/Friday as airmass over the CONUS remains too cold and dry. Some airmass modification may begin across the southern Plains late d5/Friday or early D6/Saturday as a shortwave trough progresses across the western CONUS. As the upper pattern trends more zonal across the central CONUS, surface lee troughing will sharpen, with low-level flow forecast to strengthen amid the increasing surface pressure gradient. The approaching shortwave trough is expected to continue its eastward progression into the Plains on D6/Saturday and D7/Sunday, resulting in potential interaction with this return moisture from central/eastern portions of TX/OK into the Lower MS Valley. All aspects of the approaching shortwave trough remain uncertain, with deterministic guidance showing large run-to-run variability and notable difference between the GEFS and EPS. As such, overall forecast confidence is low. However, the overall trends suggests some severe potential may materialize late this weekend into early next week. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0331 AM CST Mon Dec 30 2024 Valid 021200Z - 071200Z ...DISCUSSION... Thunderstorm chances will likely be limited on D4/Thursday and D5/Friday as airmass over the CONUS remains too cold and dry. Some airmass modification may begin across the southern Plains late d5/Friday or early D6/Saturday as a shortwave trough progresses across the western CONUS. As the upper pattern trends more zonal across the central CONUS, surface lee troughing will sharpen, with low-level flow forecast to strengthen amid the increasing surface pressure gradient. The approaching shortwave trough is expected to continue its eastward progression into the Plains on D6/Saturday and D7/Sunday, resulting in potential interaction with this return moisture from central/eastern portions of TX/OK into the Lower MS Valley. All aspects of the approaching shortwave trough remain uncertain, with deterministic guidance showing large run-to-run variability and notable difference between the GEFS and EPS. As such, overall forecast confidence is low. However, the overall trends suggests some severe potential may materialize late this weekend into early next week. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0204 AM CST Mon Dec 30 2024 Valid 311200Z - 011200Z ...Synopsis... A moderate Santa Ana wind event is expected on D2/Tuesday as offshore gradients continue across southern California D1/Monday into D2/Tuesday. Gradients will peak around 5-7 mb Tuesday night into Wednesday morning. Sustained north to northeasterly winds 15-30 mph (gusting 30-45 mph, locally up to 55 mph) will overlap minimum humidity around 10-20 percent. Elevated to locally Critical fire weather is likely across portions of the Transverse Ranges. HREF guidance indicates Critical conditions will be mainly confined to the immediate slopes/foothills, which will preclude the need for inclusion of a Critical area at this time. This will be reevaluated in future outlook updates. ..Thornton.. 12/30/2024 ...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 0204 AM CST Mon Dec 30 2024 Valid 311200Z - 011200Z ...Synopsis... A moderate Santa Ana wind event is expected on D2/Tuesday as offshore gradients continue across southern California D1/Monday into D2/Tuesday. Gradients will peak around 5-7 mb Tuesday night into Wednesday morning. Sustained north to northeasterly winds 15-30 mph (gusting 30-45 mph, locally up to 55 mph) will overlap minimum humidity around 10-20 percent. Elevated to locally Critical fire weather is likely across portions of the Transverse Ranges. HREF guidance indicates Critical conditions will be mainly confined to the immediate slopes/foothills, which will preclude the need for inclusion of a Critical area at this time. This will be reevaluated in future outlook updates. ..Thornton.. 12/30/2024 ...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 0204 AM CST Mon Dec 30 2024 Valid 311200Z - 011200Z ...Synopsis... A moderate Santa Ana wind event is expected on D2/Tuesday as offshore gradients continue across southern California D1/Monday into D2/Tuesday. Gradients will peak around 5-7 mb Tuesday night into Wednesday morning. Sustained north to northeasterly winds 15-30 mph (gusting 30-45 mph, locally up to 55 mph) will overlap minimum humidity around 10-20 percent. Elevated to locally Critical fire weather is likely across portions of the Transverse Ranges. HREF guidance indicates Critical conditions will be mainly confined to the immediate slopes/foothills, which will preclude the need for inclusion of a Critical area at this time. This will be reevaluated in future outlook updates. ..Thornton.. 12/30/2024 ...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 0204 AM CST Mon Dec 30 2024 Valid 311200Z - 011200Z ...Synopsis... A moderate Santa Ana wind event is expected on D2/Tuesday as offshore gradients continue across southern California D1/Monday into D2/Tuesday. Gradients will peak around 5-7 mb Tuesday night into Wednesday morning. Sustained north to northeasterly winds 15-30 mph (gusting 30-45 mph, locally up to 55 mph) will overlap minimum humidity around 10-20 percent. Elevated to locally Critical fire weather is likely across portions of the Transverse Ranges. HREF guidance indicates Critical conditions will be mainly confined to the immediate slopes/foothills, which will preclude the need for inclusion of a Critical area at this time. This will be reevaluated in future outlook updates. ..Thornton.. 12/30/2024 ...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 0204 AM CST Mon Dec 30 2024 Valid 311200Z - 011200Z ...Synopsis... A moderate Santa Ana wind event is expected on D2/Tuesday as offshore gradients continue across southern California D1/Monday into D2/Tuesday. Gradients will peak around 5-7 mb Tuesday night into Wednesday morning. Sustained north to northeasterly winds 15-30 mph (gusting 30-45 mph, locally up to 55 mph) will overlap minimum humidity around 10-20 percent. Elevated to locally Critical fire weather is likely across portions of the Transverse Ranges. HREF guidance indicates Critical conditions will be mainly confined to the immediate slopes/foothills, which will preclude the need for inclusion of a Critical area at this time. This will be reevaluated in future outlook updates. ..Thornton.. 12/30/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0158 AM CST Mon Dec 30 2024 Valid 011200Z - 021200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected Wednesday. ...Synopsis... Broad cyclonic flow is expected to persist across the CONUS on Wednesday as one shortwave trough exits the Northeast and a series of low-amplitude shortwave troughs follow in its wake across the Plains. Surface ridging associated with a dry continental airmass is forecast across the central and eastern CONUS, precluding any thunderstorm potential. Dry and stable conditions are anticipated across the western CONUS as well. ..Mosier.. 12/30/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0158 AM CST Mon Dec 30 2024 Valid 011200Z - 021200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected Wednesday. ...Synopsis... Broad cyclonic flow is expected to persist across the CONUS on Wednesday as one shortwave trough exits the Northeast and a series of low-amplitude shortwave troughs follow in its wake across the Plains. Surface ridging associated with a dry continental airmass is forecast across the central and eastern CONUS, precluding any thunderstorm potential. Dry and stable conditions are anticipated across the western CONUS as well. ..Mosier.. 12/30/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0158 AM CST Mon Dec 30 2024 Valid 011200Z - 021200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected Wednesday. ...Synopsis... Broad cyclonic flow is expected to persist across the CONUS on Wednesday as one shortwave trough exits the Northeast and a series of low-amplitude shortwave troughs follow in its wake across the Plains. Surface ridging associated with a dry continental airmass is forecast across the central and eastern CONUS, precluding any thunderstorm potential. Dry and stable conditions are anticipated across the western CONUS as well. ..Mosier.. 12/30/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0158 AM CST Mon Dec 30 2024 Valid 011200Z - 021200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected Wednesday. ...Synopsis... Broad cyclonic flow is expected to persist across the CONUS on Wednesday as one shortwave trough exits the Northeast and a series of low-amplitude shortwave troughs follow in its wake across the Plains. Surface ridging associated with a dry continental airmass is forecast across the central and eastern CONUS, precluding any thunderstorm potential. Dry and stable conditions are anticipated across the western CONUS as well. ..Mosier.. 12/30/2024 Read more