Active Advisories

High Wind Warningbeginning Tue 10:00 am, expires Wed 6:00 pm

* WHAT...North to northeast winds 30 to 45 mph with gusts between 60 and 80 mph expected.

* WHERE...Eastern San Fernando Valley, Eastern Santa Monica Mountains Recreational Area, Interstate 5 Corridor, Los Angeles County San Gabriel Valley, Santa Clarita Valley, and Western San Fernando Valley.

* WHEN...From 10 AM Tuesday to 6 PM PST Wednesday.

* IMPACTS...Damaging winds could blow down trees and power lines. Widespread power outages are possible. Travel will be difficult, especially for high profile vehicles.

Red Flag Warningbeginning Tue 10:00 am, expires Thu 6:00 pm

...WIDESPREAD DAMAGING NORTH TO NORTHEAST WINDS AND LONG DURATION OF RED FLAG CONDITIONS LIKELY OVER MANY PORTIONS OF LOS ANGELES AND VENTURA COUNTIES BETWEEN TUESDAY AND THURSDAY -- POSSIBLY EXTENDING INTO FRIDAY...

...RED FLAG WARNING IN EFFECT FOR MUCH OF LOS ANGELES COUNTY AND SOUTHERN VENTURA COUNTY MOUNTAINS/EASTERN VENTURA COUNTY VALLEYS FROM 10 AM TUESDAY TO 6 PM THURSDAY -- FIRE WEATHER WATCHES REMAIN THURSDAY NIGHT INTO FRIDAY...

...FIRE WEATHER WATCH REMAINS IN EFFECT FOR VENTURA COUNTY COASTAL PLAIN AND NORTHERN VENTURA MOUNTAINS FROM 10 AM TUESDAY TO 6 PM FRIDAY...

...FIRE WEATHER WATCH REMAINS IN EFFECT FROM 6 PM TUESDAY TO 8 PM WEDNESDAY FOR THE LOS ANGELES COAST, PALOS VERDES, AND CATALINA ISLAND...

.While there is still some uncertainty in this week's strong wind event and corresponding humidity levels at the onset, there is growing confidence for a widespread strong/damaging north to northeast wind event with an extended period of dangerous Red Flag conditions. While the longer duration of strong winds is expected to be focused across Los Angeles and Ventura counties, there is a 20-30 percent chance of shorter duration Red Flag conditions across portions of Santa Barbara and San Luis Obispo counties.

With widespread damaging winds likely from Tuesday afternoon into Wednesday across portions of Los Angeles and Ventura counties, there will be an increased risk for downed trees and powerlines, as well as power outages. There is also the potential for moderate to strong north to northeast winds for the LA county coast, (especially Hollywood Hills, Beverly Hills, and Sepulveda Pass) extending into Palos Verdes and Catalina Island Tuesday evening into Wednesday, resulting in the Fire Weather Watch for these areas. There is a high probability of strong mountain wave wind conditions during the peak of the event Tuesday afternoon into Wednesday, which could bring strong/damaging winds to areas that typically do not see strong winds, including portions of the San Gabriel Valley and San Fernando Valley. Fire Weather Watches have been converted to Red Flag Warnings in the Tuesday through Thursday time frame for areas where there is highest confidence of reaching critical Red Flag thresholds.

...FIRE WEATHER WATCH NOW IN EFFECT FROM THURSDAY EVENING THROUGH FRIDAY AFTERNOON FOR POTENTIAL WEAK TO MODERATE OFFSHORE WINDS AND LOW RELATIVE HUMIDITY FOR MUCH OF LOS ANGELES AND VENTURA COUNTIES...

The National Weather Service in Los Angeles/Oxnard has issued a Red Flag Warning for strong/damaging north to northeast winds and low relative humidity, which is in effect from 10 AM Tuesday to 6 PM PST Thursday.

* WINDS...Most Likely Outcome-Strong/damaging north to northeast wind event Tuesday afternoon into Wednesday with sustained winds of 35 to 55 mph and widespread damaging wind gusts of 50 to 80 mph. Strongest winds likely in the mountains, foothills, and valleys, with isolated gusts of 80 to 100 mph possible for favored foothills of the San Fernando/San Gabriel Valleys along the Highway 210 corridor from Sylmar/San Fernando eastward to foothill communities such as La Crescenta, Altadena, Monrovia, and Azusa. Moderate north to northeast winds will likely persist Thursday with gusts of 30 to 45 mph, with some weakening possible by Friday.

* RELATIVE HUMIDITY...Most Likely Outcome-Humidities likely falling to between 20 and 30 percent in many areas by early to mid Tuesday afternoon, then widespread 15 percent or less potentially Tuesday night into Friday. There is also a chance of localized single digit humidities at times Wednesday into Friday.

* IMPACTS...If fire ignition occurs, conditions are favorable for very rapid fire spread and extreme fire behavior, including long range spotting, which would threaten life and property. There will be a high potential for downed trees and powerlines, as well as power outages.

* ADDITIONAL DETAILS...Confidence is growing that this will likely be a widespread damaging windstorm across portions of Los Angeles and Ventura counties with dangerous fire weather conditions.

Fire Weather Watchbeginning Thu 6:00 pm, expires Fri 5:00 pm

...WIDESPREAD DAMAGING NORTH TO NORTHEAST WINDS AND LONG DURATION OF RED FLAG CONDITIONS LIKELY OVER MANY PORTIONS OF LOS ANGELES AND VENTURA COUNTIES BETWEEN TUESDAY AND THURSDAY -- POSSIBLY EXTENDING INTO FRIDAY...

...RED FLAG WARNING IN EFFECT FOR MUCH OF LOS ANGELES COUNTY AND SOUTHERN VENTURA COUNTY MOUNTAINS/EASTERN VENTURA COUNTY VALLEYS FROM 10 AM TUESDAY TO 6 PM THURSDAY -- FIRE WEATHER WATCHES REMAIN THURSDAY NIGHT INTO FRIDAY...

...FIRE WEATHER WATCH REMAINS IN EFFECT FOR VENTURA COUNTY COASTAL PLAIN AND NORTHERN VENTURA MOUNTAINS FROM 10 AM TUESDAY TO 6 PM FRIDAY...

...FIRE WEATHER WATCH REMAINS IN EFFECT FROM 6 PM TUESDAY TO 8 PM WEDNESDAY FOR THE LOS ANGELES COAST, PALOS VERDES, AND CATALINA ISLAND...

.While there is still some uncertainty in this week's strong wind event and corresponding humidity levels at the onset, there is growing confidence for a widespread strong/damaging north to northeast wind event with an extended period of dangerous Red Flag conditions. While the longer duration of strong winds is expected to be focused across Los Angeles and Ventura counties, there is a 20-30 percent chance of shorter duration Red Flag conditions across portions of Santa Barbara and San Luis Obispo counties.

With widespread damaging winds likely from Tuesday afternoon into Wednesday across portions of Los Angeles and Ventura counties, there will be an increased risk for downed trees and powerlines, as well as power outages. There is also the potential for moderate to strong north to northeast winds for the LA county coast, (especially Hollywood Hills, Beverly Hills, and Sepulveda Pass) extending into Palos Verdes and Catalina Island Tuesday evening into Wednesday, resulting in the Fire Weather Watch for these areas. There is a high probability of strong mountain wave wind conditions during the peak of the event Tuesday afternoon into Wednesday, which could bring strong/damaging winds to areas that typically do not see strong winds, including portions of the San Gabriel Valley and San Fernando Valley. Fire Weather Watches have been converted to Red Flag Warnings in the Tuesday through Thursday time frame for areas where there is highest confidence of reaching critical Red Flag thresholds.

...FIRE WEATHER WATCH NOW IN EFFECT FROM THURSDAY EVENING THROUGH FRIDAY AFTERNOON FOR POTENTIAL WEAK TO MODERATE OFFSHORE WINDS AND LOW RELATIVE HUMIDITY FOR MUCH OF LOS ANGELES AND VENTURA COUNTIES...

The National Weather Service in Los Angeles/Oxnard has issued a Red Flag Warning for strong/damaging north to northeast winds and low relative humidity, which is in effect from 10 AM Tuesday to 6 PM PST Thursday.

* WINDS...Most Likely Outcome-Strong/damaging north to northeast wind event Tuesday afternoon into Wednesday with sustained winds of 35 to 55 mph and widespread damaging wind gusts of 50 to 80 mph. Strongest winds likely in the mountains, foothills, and valleys, with isolated gusts of 80 to 100 mph possible for favored foothills of the San Fernando/San Gabriel Valleys along the Highway 210 corridor from Sylmar/San Fernando eastward to foothill communities such as La Crescenta, Altadena, Monrovia, and Azusa. Moderate north to northeast winds will likely persist Thursday with gusts of 30 to 45 mph, with some weakening possible by Friday.

* RELATIVE HUMIDITY...Most Likely Outcome-Humidities likely falling to between 20 and 30 percent in many areas by early to mid Tuesday afternoon, then widespread 15 percent or less potentially Tuesday night into Friday. There is also a chance of localized single digit humidities at times Wednesday into Friday.

* IMPACTS...If fire ignition occurs, conditions are favorable for very rapid fire spread and extreme fire behavior, including long range spotting, which would threaten life and property. There will be a high potential for downed trees and powerlines, as well as power outages.

* ADDITIONAL DETAILS...Confidence is growing that this will likely be a widespread damaging windstorm across portions of Los Angeles and Ventura counties with dangerous fire weather conditions.

Air Quality Alertuntil Tue 12:00 am

* WHAT...The South Coast AQMD has issued a mandatory wood-burning ban for residents in the South Coast Air Basin. The No-Burn rule bans burning wood, pellets, and manufactured fire logs in any indoor or outdoor wood-burning device.

* WHERE...The South Coast Air Basin, which includes Orange County and non-desert portions of Los Angeles, Riverside, and San Bernardino counties. No-Burn Day alerts do not apply to areas above 3,000 feet in elevation, the Coachella Valley, or the High Desert. Homes that rely on wood as a sole source of heat, low-income households and those without natural gas service also are exempt from the requirement.

* WHEN...Monday, January 6, 2025.

* IMPACTS...Particles in smoke can get deep into the lungs and cause health problems (including asthma attacks), increases in emergency room visits, and hospitalizations. No-Burn Days are needed to protect public health when fine particle pollution levels are expected to be high anywhere in the South Coast Air Basin. No-Burn Days are based on fine particle pollution levels that are forecasted for an entire 24-hour period, which may not be reflected in real- time air quality maps.

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