As Malibu's Franklin Fire rages, rare weather advisory warns of "dangerous" wildfire weather

A Malibu wildfire that has forced people to evacuate and destroyed homes broke out amid a rare weather advisory warning of particularly dangerous conditions increasing the risk of fires — and the forecast will remain in place through Wednesday afternoon. 

The National Weather Service extended its red flag warning for parts of the San Gabriel Mountains, Santa Monica Mountains, Ventura County Coasts and Valleys and the Ventura County Mountains until 6 p.m. The warning also remains in effect in around the Malibu Coast until 2 p.m. The NWS has warned of "damaging" Santa Ana winds, with gusts that could reach up to around 40 to 60 miles per hour. It's part of a weather advisory known as a "Particularly Dangerous Situation" (PDS) Red Flag warning, a higher level of the typical red flag warning issued for wildfire weather and the same one that was in place when the devastating Mountain Fire tore through Ventura County last month. 

It's typically announced only once every few years, forecasters have said. Before the PDS warning ahead of the Mountain Fire in November, the last time it was issued was in 2020, the Los Angeles Times reports. 

Given the strong winds, the South Coast Air Quality Management District has issued a windblown dust advisory — warning of unhealthy air quality from gusts picking up dust and soil through the air. It will remain in effect until 6 p.m. Tuesday, with a smoke advisory also issued by the air quality regulator — due to widespread smoke and ash from the wildfire — and in effect through Wednesday.   

In the advisory, forecasters say the "hardest hit" parts of Southern California will be the Santa Monica Mountains neighboring the Malibu coastline, the San Gabriel Mountains, the western San Fernando Valley and the valleys of Ventura County, particularly Simi Valley, Moorpark and the hills above Camarillo into east Ventura. 

The Santa Clarita Valley, Calabasas and other western areas of Los Angeles County will also be affected but to a lesser extent.

Powerful Santa Ana winds blowing through the region, along with extremely low humidity increasing the risk of wildfires sparking and spreading, have been forecasted to last through 2 p.m. Tuesday as part of the PDS Red Flag warning. A regular Red Flag warning, with conditions carrying less risks and potential dangers, will be in place in the same areas through 6 p.m. Wednesday.

Other parts of the region will face Red Flag warnings in effect until 2 p.m. Wednesday.

"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," the advisory from the National Weather Service reads, noting that Santa Ana winds are expected to peak Tuesday afternoon. 

The coastal areas, foothills and mountains of Ventura County and neighboring parts of LA County are expected to face the brunt of the dangerous winds, with gusts that could reach up to 60 to 80 miles per hour coupled with extremely low humidity. 

"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 advisory reads.

The Franklin Fire in Malibu broke out amid the relatively rare weather advisory, sparking around 10:45 p.m. Monday near the Pepperdine University Campus before burning down homes and forcing people to evacuate from the area.