Powerful winds blew across the Southland amid low humidity today, raising fears of wildfires in Orange County through Thursday.
National Weather Service forecasters initially issued a fire weather watch for Wednesday, but the watch was boosted to a red flag warning indicating critical weather conditions will be in place for much of the day tomorrow.
"A trough of low pressure near Idaho is expected to drop south into Eastern California by Wednesday," according to an NWS advisory.
Forecasters said the system will bring winds of around 40 mph, with gusts up to 65 mph in the windiest locations.
"While humidities will increase some tonight, especially in the mountains, they will gradually lower to below 15 percent through the day on Wednesday, first near the coast early Wednesday morning then up through the higher elevations in the afternoon," according to the NWS. "Despite the initially higher humidities, the strong wind potential will bring a potential for extreme fire behavior if a fire started."
Forecasters noted that today and Thursday will also be "periods of high fire weather concern," with red flag conditions possible.
The red flag warning will cover Orange County coastal areas, the Santa Ana Mountains and portions of the Cleveland National Forest.
A high wind warning will take effect at 10 p.m. in many areas and continue until 3 p.m. Wednesday. Forecasters said gusts as high as 70 mph are possible on some peaks and ridges and through passes and canyons.
The NWS forecast partly cloudy skies today but sunny skies Wednesday, when temperatures will climb a few degrees in most communities. It forecast highs 71 today, 73 Wednesday in Newport Beach; 78 today, 77 Wednesday in Anaheim.
--City News Service