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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0105 PM CST Sun Jan 19 2025 Valid 201200Z - 211200Z ...EXTREMELY CRITICAL FIRE WEATHER AREA FOR THE SAN GABRIEL MOUNTAINS WESTWARD TOWARD THE SANTA SUSANA MOUNTAINS AND SANTA MONICA MOUNTAINS...INCLUDING THE MALIBU COAST... ...CRITICAL FIRE WEATHER AREA FOR MUCH OF SOUTHERN CALIFORNIA... The primary change with this update was an expansion of the Extremely Critical highlights to the Malibu Coast. Here, the latest high-resolution guidance is in relatively good agreement, depicting 30-40 mph northeasterly surface winds (with gusts upwards of 60-70 mph) amid single-digit to lower teens RH. These dangerous fire-weather conditions will continue into Day 3/Tuesday morning. Farther south, the Critical area was also extended to the coast in Orange County and northern San Diego County, where confidence in the development of 20-30 mph northeasterly surface winds (with higher gusts) has increased. For portions of inland Orange and San Diego Counties, localized extremely critical conditions are expected -- especially over the wind-prone mountains, foothills, and valleys. For additional details, see the previous discussion below. ..Weinman.. 01/19/2025 .PREV DISCUSSION... /ISSUED 0142 AM CST Sun Jan 19 2025/ ...Synopsis... A positively tilted shortwave trough is forecast to move southward out of the Pacific Northwest and into Southern California late Sunday night into early Tuesday Morning. By Monday afternoon, strong mid-level northerly flow will reach Southern California, with an amplified mid-level ridge following behind the trough and moving east out of the Eastern Pacific. These upper-level features, in combination with strengthening surface high pressure over the Intermountain West, will result in a tight surface pressure gradient directed offshore. The pressure gradient magnitudes suggest strong Santa Ana winds developing as a result, lasting from Monday night through Tuesday morning. Recent high-resolution forecast guidance has increased the confidence in strong surface pressure gradients and strong surface winds enough to introduce an Extremely Critical area, extending from the San Gabriel Mountains westward to the Santa Monica Mountains and Santa Susana Mountains. Forecasts continue to show strong surface pressure gradients from LAX->DAG anywhere from -8 mb to -11 mb, resulting in sustained surface winds of 35-40 MPH (gusting 60-80 MPH). These dry and windy conditions, coupled with dry and receptive fuels, will result Extremely Critical conditions supportive of rapid wildfire onset and spread. Critical fire-weather highlights extend into San Diego county, where recent model guidance continues to increase confidence in strong offshore flow and dry conditions overnight Monday into Tuesday morning. ...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 0105 PM CST Sun Jan 19 2025 Valid 201200Z - 211200Z ...EXTREMELY CRITICAL FIRE WEATHER AREA FOR THE SAN GABRIEL MOUNTAINS WESTWARD TOWARD THE SANTA SUSANA MOUNTAINS AND SANTA MONICA MOUNTAINS...INCLUDING THE MALIBU COAST... ...CRITICAL FIRE WEATHER AREA FOR MUCH OF SOUTHERN CALIFORNIA... The primary change with this update was an expansion of the Extremely Critical highlights to the Malibu Coast. Here, the latest high-resolution guidance is in relatively good agreement, depicting 30-40 mph northeasterly surface winds (with gusts upwards of 60-70 mph) amid single-digit to lower teens RH. These dangerous fire-weather conditions will continue into Day 3/Tuesday morning. Farther south, the Critical area was also extended to the coast in Orange County and northern San Diego County, where confidence in the development of 20-30 mph northeasterly surface winds (with higher gusts) has increased. For portions of inland Orange and San Diego Counties, localized extremely critical conditions are expected -- especially over the wind-prone mountains, foothills, and valleys. For additional details, see the previous discussion below. ..Weinman.. 01/19/2025 .PREV DISCUSSION... /ISSUED 0142 AM CST Sun Jan 19 2025/ ...Synopsis... A positively tilted shortwave trough is forecast to move southward out of the Pacific Northwest and into Southern California late Sunday night into early Tuesday Morning. By Monday afternoon, strong mid-level northerly flow will reach Southern California, with an amplified mid-level ridge following behind the trough and moving east out of the Eastern Pacific. These upper-level features, in combination with strengthening surface high pressure over the Intermountain West, will result in a tight surface pressure gradient directed offshore. The pressure gradient magnitudes suggest strong Santa Ana winds developing as a result, lasting from Monday night through Tuesday morning. Recent high-resolution forecast guidance has increased the confidence in strong surface pressure gradients and strong surface winds enough to introduce an Extremely Critical area, extending from the San Gabriel Mountains westward to the Santa Monica Mountains and Santa Susana Mountains. Forecasts continue to show strong surface pressure gradients from LAX->DAG anywhere from -8 mb to -11 mb, resulting in sustained surface winds of 35-40 MPH (gusting 60-80 MPH). These dry and windy conditions, coupled with dry and receptive fuels, will result Extremely Critical conditions supportive of rapid wildfire onset and spread. Critical fire-weather highlights extend into San Diego county, where recent model guidance continues to increase confidence in strong offshore flow and dry conditions overnight Monday into Tuesday morning. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0104 PM CST Sun Jan 19 2025 Valid 211200Z - 221200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast on Tuesday or Tuesday night. ...Synopsis... Thunderstorm potential largely appears negligible across the CONUS through Tuesday night. An exception could be along the Gulf Coast. Shallow and highly elevated convection, predominately producing sleet at the surface, should be ongoing at 12Z Tuesday along the northwest Gulf Coast. Mid-level lapse rates will be progressively weaker with eastern extent downstream, suggesting that lightning production will likely be nonexistent along the north-central to eastern Gulf Coast. Primary deep convective potential should be confined from the west-central to southeast Gulf through the period. ..Grams.. 01/19/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0104 PM CST Sun Jan 19 2025 Valid 211200Z - 221200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast on Tuesday or Tuesday night. ...Synopsis... Thunderstorm potential largely appears negligible across the CONUS through Tuesday night. An exception could be along the Gulf Coast. Shallow and highly elevated convection, predominately producing sleet at the surface, should be ongoing at 12Z Tuesday along the northwest Gulf Coast. Mid-level lapse rates will be progressively weaker with eastern extent downstream, suggesting that lightning production will likely be nonexistent along the north-central to eastern Gulf Coast. Primary deep convective potential should be confined from the west-central to southeast Gulf through the period. ..Grams.. 01/19/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0104 PM CST Sun Jan 19 2025 Valid 211200Z - 221200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast on Tuesday or Tuesday night. ...Synopsis... Thunderstorm potential largely appears negligible across the CONUS through Tuesday night. An exception could be along the Gulf Coast. Shallow and highly elevated convection, predominately producing sleet at the surface, should be ongoing at 12Z Tuesday along the northwest Gulf Coast. Mid-level lapse rates will be progressively weaker with eastern extent downstream, suggesting that lightning production will likely be nonexistent along the north-central to eastern Gulf Coast. Primary deep convective potential should be confined from the west-central to southeast Gulf through the period. ..Grams.. 01/19/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0104 PM CST Sun Jan 19 2025 Valid 211200Z - 221200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast on Tuesday or Tuesday night. ...Synopsis... Thunderstorm potential largely appears negligible across the CONUS through Tuesday night. An exception could be along the Gulf Coast. Shallow and highly elevated convection, predominately producing sleet at the surface, should be ongoing at 12Z Tuesday along the northwest Gulf Coast. Mid-level lapse rates will be progressively weaker with eastern extent downstream, suggesting that lightning production will likely be nonexistent along the north-central to eastern Gulf Coast. Primary deep convective potential should be confined from the west-central to southeast Gulf through the period. ..Grams.. 01/19/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0104 PM CST Sun Jan 19 2025 Valid 211200Z - 221200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast on Tuesday or Tuesday night. ...Synopsis... Thunderstorm potential largely appears negligible across the CONUS through Tuesday night. An exception could be along the Gulf Coast. Shallow and highly elevated convection, predominately producing sleet at the surface, should be ongoing at 12Z Tuesday along the northwest Gulf Coast. Mid-level lapse rates will be progressively weaker with eastern extent downstream, suggesting that lightning production will likely be nonexistent along the north-central to eastern Gulf Coast. Primary deep convective potential should be confined from the west-central to southeast Gulf through the period. ..Grams.. 01/19/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0104 PM CST Sun Jan 19 2025 Valid 211200Z - 221200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast on Tuesday or Tuesday night. ...Synopsis... Thunderstorm potential largely appears negligible across the CONUS through Tuesday night. An exception could be along the Gulf Coast. Shallow and highly elevated convection, predominately producing sleet at the surface, should be ongoing at 12Z Tuesday along the northwest Gulf Coast. Mid-level lapse rates will be progressively weaker with eastern extent downstream, suggesting that lightning production will likely be nonexistent along the north-central to eastern Gulf Coast. Primary deep convective potential should be confined from the west-central to southeast Gulf through the period. ..Grams.. 01/19/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0104 PM CST Sun Jan 19 2025 Valid 211200Z - 221200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast on Tuesday or Tuesday night. ...Synopsis... Thunderstorm potential largely appears negligible across the CONUS through Tuesday night. An exception could be along the Gulf Coast. Shallow and highly elevated convection, predominately producing sleet at the surface, should be ongoing at 12Z Tuesday along the northwest Gulf Coast. Mid-level lapse rates will be progressively weaker with eastern extent downstream, suggesting that lightning production will likely be nonexistent along the north-central to eastern Gulf Coast. Primary deep convective potential should be confined from the west-central to southeast Gulf through the period. ..Grams.. 01/19/2025 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0104 PM CST Sun Jan 19 2025 Valid 211200Z - 221200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast on Tuesday or Tuesday night. ...Synopsis... Thunderstorm potential largely appears negligible across the CONUS through Tuesday night. An exception could be along the Gulf Coast. Shallow and highly elevated convection, predominately producing sleet at the surface, should be ongoing at 12Z Tuesday along the northwest Gulf Coast. Mid-level lapse rates will be progressively weaker with eastern extent downstream, suggesting that lightning production will likely be nonexistent along the north-central to eastern Gulf Coast. Primary deep convective potential should be confined from the west-central to southeast Gulf through the period. ..Grams.. 01/19/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1118 AM CST Sun Jan 19 2025 Valid 201200Z - 211200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast on Monday or Monday night. ...Synopsis... Thunderstorm potential is negligible across the CONUS on Monday through Monday night. One exception could be from the Middle TX to southwest LA Gulf Coast where weak elevated convection should develop early morning Tuesday. This will occur with strengthening warm-moist advection centered on 750-700 mb, downstream of a positive-tilt mid/upper-level longwave trough. Some CAM/non-CAM 12Z forecast soundings, most aggressively from the NAM, depict scant elevated buoyancy developing amid a plume of initially steep mid-level lapse rates. With thermodynamic profiles suggestive of a predominant PTYPE of sleet at the surface, these potentially mixed-phase elevated parcels could support a few lightning flashes. While thunderstorm probabilities may be nonzero, they appear to be less than 10 percent at this time. ..Grams.. 01/19/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1118 AM CST Sun Jan 19 2025 Valid 201200Z - 211200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast on Monday or Monday night. ...Synopsis... Thunderstorm potential is negligible across the CONUS on Monday through Monday night. One exception could be from the Middle TX to southwest LA Gulf Coast where weak elevated convection should develop early morning Tuesday. This will occur with strengthening warm-moist advection centered on 750-700 mb, downstream of a positive-tilt mid/upper-level longwave trough. Some CAM/non-CAM 12Z forecast soundings, most aggressively from the NAM, depict scant elevated buoyancy developing amid a plume of initially steep mid-level lapse rates. With thermodynamic profiles suggestive of a predominant PTYPE of sleet at the surface, these potentially mixed-phase elevated parcels could support a few lightning flashes. While thunderstorm probabilities may be nonzero, they appear to be less than 10 percent at this time. ..Grams.. 01/19/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1118 AM CST Sun Jan 19 2025 Valid 201200Z - 211200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast on Monday or Monday night. ...Synopsis... Thunderstorm potential is negligible across the CONUS on Monday through Monday night. One exception could be from the Middle TX to southwest LA Gulf Coast where weak elevated convection should develop early morning Tuesday. This will occur with strengthening warm-moist advection centered on 750-700 mb, downstream of a positive-tilt mid/upper-level longwave trough. Some CAM/non-CAM 12Z forecast soundings, most aggressively from the NAM, depict scant elevated buoyancy developing amid a plume of initially steep mid-level lapse rates. With thermodynamic profiles suggestive of a predominant PTYPE of sleet at the surface, these potentially mixed-phase elevated parcels could support a few lightning flashes. While thunderstorm probabilities may be nonzero, they appear to be less than 10 percent at this time. ..Grams.. 01/19/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1118 AM CST Sun Jan 19 2025 Valid 201200Z - 211200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast on Monday or Monday night. ...Synopsis... Thunderstorm potential is negligible across the CONUS on Monday through Monday night. One exception could be from the Middle TX to southwest LA Gulf Coast where weak elevated convection should develop early morning Tuesday. This will occur with strengthening warm-moist advection centered on 750-700 mb, downstream of a positive-tilt mid/upper-level longwave trough. Some CAM/non-CAM 12Z forecast soundings, most aggressively from the NAM, depict scant elevated buoyancy developing amid a plume of initially steep mid-level lapse rates. With thermodynamic profiles suggestive of a predominant PTYPE of sleet at the surface, these potentially mixed-phase elevated parcels could support a few lightning flashes. While thunderstorm probabilities may be nonzero, they appear to be less than 10 percent at this time. ..Grams.. 01/19/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1118 AM CST Sun Jan 19 2025 Valid 201200Z - 211200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast on Monday or Monday night. ...Synopsis... Thunderstorm potential is negligible across the CONUS on Monday through Monday night. One exception could be from the Middle TX to southwest LA Gulf Coast where weak elevated convection should develop early morning Tuesday. This will occur with strengthening warm-moist advection centered on 750-700 mb, downstream of a positive-tilt mid/upper-level longwave trough. Some CAM/non-CAM 12Z forecast soundings, most aggressively from the NAM, depict scant elevated buoyancy developing amid a plume of initially steep mid-level lapse rates. With thermodynamic profiles suggestive of a predominant PTYPE of sleet at the surface, these potentially mixed-phase elevated parcels could support a few lightning flashes. While thunderstorm probabilities may be nonzero, they appear to be less than 10 percent at this time. ..Grams.. 01/19/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1118 AM CST Sun Jan 19 2025 Valid 201200Z - 211200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast on Monday or Monday night. ...Synopsis... Thunderstorm potential is negligible across the CONUS on Monday through Monday night. One exception could be from the Middle TX to southwest LA Gulf Coast where weak elevated convection should develop early morning Tuesday. This will occur with strengthening warm-moist advection centered on 750-700 mb, downstream of a positive-tilt mid/upper-level longwave trough. Some CAM/non-CAM 12Z forecast soundings, most aggressively from the NAM, depict scant elevated buoyancy developing amid a plume of initially steep mid-level lapse rates. With thermodynamic profiles suggestive of a predominant PTYPE of sleet at the surface, these potentially mixed-phase elevated parcels could support a few lightning flashes. While thunderstorm probabilities may be nonzero, they appear to be less than 10 percent at this time. ..Grams.. 01/19/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1118 AM CST Sun Jan 19 2025 Valid 201200Z - 211200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast on Monday or Monday night. ...Synopsis... Thunderstorm potential is negligible across the CONUS on Monday through Monday night. One exception could be from the Middle TX to southwest LA Gulf Coast where weak elevated convection should develop early morning Tuesday. This will occur with strengthening warm-moist advection centered on 750-700 mb, downstream of a positive-tilt mid/upper-level longwave trough. Some CAM/non-CAM 12Z forecast soundings, most aggressively from the NAM, depict scant elevated buoyancy developing amid a plume of initially steep mid-level lapse rates. With thermodynamic profiles suggestive of a predominant PTYPE of sleet at the surface, these potentially mixed-phase elevated parcels could support a few lightning flashes. While thunderstorm probabilities may be nonzero, they appear to be less than 10 percent at this time. ..Grams.. 01/19/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1118 AM CST Sun Jan 19 2025 Valid 201200Z - 211200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast on Monday or Monday night. ...Synopsis... Thunderstorm potential is negligible across the CONUS on Monday through Monday night. One exception could be from the Middle TX to southwest LA Gulf Coast where weak elevated convection should develop early morning Tuesday. This will occur with strengthening warm-moist advection centered on 750-700 mb, downstream of a positive-tilt mid/upper-level longwave trough. Some CAM/non-CAM 12Z forecast soundings, most aggressively from the NAM, depict scant elevated buoyancy developing amid a plume of initially steep mid-level lapse rates. With thermodynamic profiles suggestive of a predominant PTYPE of sleet at the surface, these potentially mixed-phase elevated parcels could support a few lightning flashes. While thunderstorm probabilities may be nonzero, they appear to be less than 10 percent at this time. ..Grams.. 01/19/2025 Read more

No Mesoscale Discussions are in effect as of Sun Jan 19 17:22:02 UTC 2025.

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1018 AM CST Sun Jan 19 2025 Valid 191630Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER THE CENTRAL FLORIDA PENINSULA... ...SUMMARY... Strong thunderstorms may impact parts of central Florida this morning into this afternoon, and pose at least some risk for a tornado and locally damaging wind gusts. ...FL Peninsula... Expansive upper troughing covers the entirety of the CONUS this morning, with moderate southwesterly flow aloft throughout the base of this trough extending from the Southeast/Gulf of Mexico across the Mid-Atlantic States and FL. Surface analysis places a low over central NC. A cold front extends southwestward from this low through southeast GA and the FL Big Bend. Modest troughing precedes this front across central FL, with broad low-level confluence in the vicinity of this pre-frontal troughing contributing to showers and thunderstorms. Modest buoyancy persists over the region, with mesoanalysis estimating MLCAPE around 500 to 750 J/kg. Showers and thunderstorms are expected to continue throughout the day as the cold front and pre-frontal troughing both shift gradually southward. The environment will remain strongly sheared (i.e. effective bulk shear around 50-55 kt) throughout the afternoon, supporting the potential for a few more organized storms capable of damaging wind gusts and perhaps even a brief tornado or two. Wind fields will weaken with southern extent, with deep-layer vertical shear weakening as well. As such, the severe potential will likely maximize this morning into the early afternoon across the central FL Peninsula. ..Mosier/Jirak.. 01/19/2025 Read more