Hazard Report Provided By forecast.weather.gov
URGENT - FIRE WEATHER MESSAGE National Weather Service Los Angeles/Oxnard CA 906 AM PST Tue Dec 10 2024 ...PARTICULARLY DANGEROUS SITUATION (PDS) RED FLAG WARNING IN EFFECT UNTIL 2 PM TODAY DUE TO DAMAGING SANTA ANA WINDS AND VERY LOW HUMIDITIES FOR THE FOLLOWING AREAS: SAN GABRIEL MOUNTAINS/ SANTA MONICA MOUNTAINS/ SANTA CLARITA VALLEY/ CALABASAS/ VENTURA COUNTY COASTS AND VALLEYS/ WESTERN SAN FERNANDO VALLEY -- AND RED FLAG WARNINGS IN EFFECT FOR ALL OTHER TIMES UNTIL 6 PM WEDNESDAY IN THESE SAME AREAS... ...PARTICULARLY DANGEROUS SITUATION (PDS) RED FLAG WARNING IN EFFECT UNTIL 10 AM WEDNESDAY DUE TO DAMAGING SANTA ANA WINDS AND VERY LOW HUMIDITIES FOR THE FOLLOWING AREAS: SANTA SUSANA MOUNTAINS-- AND RED FLAG WARNINGS IN EFFECT FOR ALL OTHER TIMES UNTIL 6 PM WEDNESDAY IN THIS SAME AREA... ...PARTICULARLY DANGEROUS SITUATION (PDS) RED FLAG WARNING IN EFFECT UNTIL 2 PM TODAY DUE TO DAMAGING SANTA ANA WINDS AND VERY LOW HUMIDITIES FOR THE FOLLOWING AREAS: VENTURA COASTAL PLAIN (ESPECIALLY FOOTHILLS)/ MALIBU COAST -- AND RED FLAG WARNINGS IN EFFECT FOR ALL OTHER TIMES FROM 2 PM MONDAY UNTIL 2 PM WEDNESDAY IN THESE SAME AREAS... ...RED FLAG WARNING IN EFFECT UNTIL 6 PM WEDNESDAY FOR VENTURA MOUNTAINS, I5 CORRIDOR, EASTERN SAN FERNANDO VALLEY, AND SAN GABRIEL VALLEY DUE TO GUSTY SANTA ANA WINDS AND VERY LOW HUMIDITIES... ...RED FLAG WARNING IN EFFECT UNTIL 10 PM THIS EVENING FOR THE SAN LUIS OBISPO COUNTY MOUNTAINS DUE TO GUSTY EAST TO SOUTHEAST WINDS AND VERY LOW HUMIDITIES... ...RED FLAG WARNING IN EFFECT UNTIL 2 PM TODAY FOR THE CHANNEL ISLANDS AND PALOS VERDES DUE TO GUSTY SANTA ANA WINDS AND VERY LOW HUMIDITIES... ***THIS IS A PARTICULARLY DANGEROUS SITUATION (PDS) FOR MANY AREAS OF LOS ANGELES AND VENTURA COUNTIES *** A strong, widespread, and long duration Santa Ana event will bring widespread critical to extremely critical fire weather conditions to many areas of Los Angeles and Ventura counties through Wednesday. This will be a PARTICULARLY DANGEROUS SITUATION (PDS) Red Flag Warning event in many areas, with the combination of a strong offshore pressure gradient, strong cold air advection, and moderate upper level wind support. As surface high pressure builds into the Great Basin, Santa Ana winds will continue today into Wednesday, peaking through early this afternoon. The offshore winds are expected to diminish some by Wednesday, but a very dry air mass will persist. With the strong likelihood of widespread single digit humidities with this event, there is high confidence for a long duration Red Flag event. In addition, there is high confidence of PDS Red Flag Warning conditions through early this afternoon, as damaging wind gusts of 60 to 80 mph will likely overlap with single digit humidities across many of the windier mountain and foothill areas. Peak gusts of 40 to 65 mph will also affect most wind prone coastal and valley areas of Los Angeles and Ventura counties. With the threat of damaging wind gusts in these windier corridors, there will be an increased risk for downed trees and powerlines, along with power outages. The hardest hit areas will likely be the San Gabriels, Santa Susanas, western Santa Monicas into Malibu, Ventura county valleys (especially Simi Valley and Moorpark), western San Fernando Valley (especially Highway 118/210 corridors from Porter Ranch to San Fernando), and the hills above Camarillo into east Ventura. Due to the expected long duration of dangerous fire weather conditions and critically dry fuels, there is an increased risk for any new ignitions to have very rapid fire spread and extreme fire behavior (including long range spotting). As a result, there is the increasing threat for fire weather conditions to rival other historical fires in recent times including the Mountain and Thomas Fires. Dry offshore conditions will likely persist into Thursday morning, with a return of onshore flow and some humidity recovery in the afternoon. CAZ288-358-369>372-374-379-380-110115- /O.CON.KLOX.FW.W.0013.000000T0000Z-241212T0200Z/ Santa Clarita Valley-Central Ventura County Valleys- Western Santa Monica Mountains Recreational Area- Eastern Santa Monica Mountains Recreational Area- Calabasas and Agoura Hills-Western San Fernando Valley- Southeastern Ventura County Valleys- Western San Gabriel Mountains and Highway 14 Corridor- Eastern San Gabriel Mountains- 906 AM PST Tue Dec 10 2024 ...PARTICULARLY DANGEROUS SITUATION (PDS) RED FLAG WARNING IN EFFECT UNTIL 2 PM TODAY DUE TO DAMAGING SANTA ANA WINDS AND VERY LOW HUMIDITIES FOR THE FOLLOWING AREAS: SAN GABRIEL MOUNTAINS/ SANTA MONICA MOUNTAINS/ SANTA CLARITA VALLEY/ VENTURA COUNTY COASTS AND VALLEYS/ WESTERN SAN FERNANDO VALLEY -- AND RED FLAG WARNINGS IN EFFECT FOR ALL OTHER TIMES UNTIL 6 PM WEDNESDAY IN THESE SAME AREAS... * WINDS...Santa Ana winds will peak today with speeds of 25 to 40 mph gusting to 45 to 65 mph common across coastal and valley areas. Some of the windier foothills and mountains will likely see wind speeds of 30 to 50 mph with damaging wind gusts in the 60 to 80 mph range during the peak of the event through early this afternoon. Some of the highest wind areas will likely be the San Gabriels, Santa Susanas, western Santa Monicas into Malibu, Ventura county valleys (especially Simi Valley and Moorpark), and western San Fernando Valley (especially Highway 118/210 corridors from Porter Ranch to San Fernando). Offshore winds are expected to diminish some by Wednesday, with gusts mostly in the 20 to 40 mph range in the morning. * RELATIVE HUMIDITY...Widespread humidities of 5 to 10 percent are likely today, persisting into Wednesday, with isolated readings as low as 2 percent possible. * IMPACTS...If fire ignition occurs, conditions are favorable for large fires with very rapid fire spread, extreme fire behavior, and long range spotting, which would threaten life and property. There is also the risk of damaging winds including downed trees and power lines, as well as power outages. PRECAUTIONARY/PREPAREDNESS ACTIONS... A Red Flag Warning means that critical fire weather conditions are either occurring now, or will shortly. Use extreme caution with anything that can spark a wildfire. Residents near wildland interfaces should be prepared to evacuate if a wildfire breaks out. See readyforwildfire.org and wildfirerisk.org for information. && $$
Hazard Report Provided By forecast.weather.gov