Southern California is preparing for the onset of Santa Ana winds beginning Wednesday, which are expected to drive up temperatures and elevate the risk of wildfires across the region. National Weather Service (NWS) forecasters indicate a noticeable change in weather conditions, with temperatures steadily rising into the weekend.
According to the NWS, temperatures across coastal and valley areas, including Irvine, are projected to warm by approximately 10 degrees each day. Highs are expected to peak on Friday, reaching the upper 80s to mid 90s in most areas.
Wind speeds will progressively increase from Wednesday through Friday. Light north-northeast winds began developing over mountain areas Tuesday night, and will gain speed daily, with winds aloft potentially reaching 40 to 50 mph by Friday. Forecasters noted that Friday will experience the strongest winds, with Thursday not far behind. Gusts of 60 to 70 mph are possible in wind-prone areas of the San Gabriel Mountains, though specific wind advisories have been issued for areas including the Malibu Coast, Santa Clarita and San Fernando valleys, and parts of the Santa Monica Mountains Recreational Area.
As is typical with Santa Ana wind events, the combination of gusty conditions and dry air will significantly increase the risk of wildfires. The NWS has issued a Fire Weather Watch that will be in effect from Thursday morning through Friday evening for several areas. These include the San Gabriel Mountains, the Santa Monica Mountains Recreational Area, and the corridors of the Golden State (5) and Antelope Valley (14) freeways. In these areas, northeast winds of 20 to 40 mph, gusting from 50 to 70 mph, are expected alongside humidity levels dropping to between 8% and 20%.
A separate Fire Weather Watch will be in place during the same period for the San Fernando, Santa Clarita, and San Gabriel valleys, as well as the Malibu Coast and Calabasas. These areas could see winds of 20 to 30 mph, with gusts reaching 40 to 50 mph, and some isolated gusts up to 60 mph possible in the hills. Humidity levels are anticipated to fall even lower, to between 5% and 15%.
According to the NWS, “A Fire Weather Watch means that critical fire weather conditions are likely to occur in the coming days.” Residents near wildland interfaces throughout the region are advised to prepare now for what to do should a wildfire break out. Forecasters expect that these Fire Weather Watches will likely be upgraded to Red Flag Warnings by Wednesday, indicating a critical wildfire danger that could extend into Saturday.
Meanwhile, high surf that had been a concern in some coastal areas of Orange County and Long Beach earlier in the week, a remnant of former Tropical Storm Rachel, has been diminishing. While surf remained treacherous Tuesday morning and coastal flood advisories were in effect for Los Angeles County beaches until Tuesday afternoon, attention has now fully shifted to the incoming wind and heat.
Heat advisories will also take effect at 10 a.m. Thursday and continue through Saturday for specific areas, including the Malibu Coast, Los Angeles County beaches, the Palos Verdes Hills, and the Inland Coast, encompassing downtown Los Angeles.
