Parts of Southern California were under a flash flood watch Wednesday as areas of the southwest saw the first significant rainfall of a delayed wet season that fueled wildfires and forced intermittent power cutoffs to millions of residents.
The storm system brought heavy rain to portions of Arizona, and Phoenix could get 2 inches of rain before the storm ends there on Thursday. Prior to this storm, Sky Harbor International Airport had recorded only 3.68 inches for the entire year.
Los Angeles has only had one day of traceable rain in almost two months. But an upper level, low pressure system approaching the California coast was bringing "significantly cooler and showery conditions" to the Los Angeles and San Diego areas, the National Weather Service said.
"They got a little bit of rain overnight," AccuWeather senior meteorologist Tony Zartman told USA TODAY. "I think they will get some more rain later today, but San Diego will get more."
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Los Angeles can expect no more than one-tenth of an inch of rain, with up to a half-inch in the mountain areas. San Diego could see a quarter-inch, with mountain areas of San Diego County getting another inch in the mountains.
"It won't make much of a difference in Los Angeles, maybe a bit more impact in San Diego County," Zartman said. "It won't be the long, soaking rain they need. But at least that dry brush will get a little moisture on it, which could reduce wildfire threat."
Still, the National Weather Service said the "best dynamics" for rain will be focused from Los Angeles County to Orange County with much less shower activity across Ventura and other areas northwest of the city.
Precipitation has been so rare that the Los Angeles Times included a link on "How to drive in the rain" on its website.
To the east, the rains were in full force Wednesday. Caltrans was tweeting warnings of flooding on multiple roads. The National Weather Service issued a flash flood warning for San Bernardino and Riverside counties, saying localized, heavy rainfall could drive mudslides through steep terrain in recently burned areas.
"Some areas already have seen 2 inches, and you are talking about some places that normally get maybe a half inch for November and December combined," Zartman said. "They are hit hard, but a lot of it will just run off."
Much of the state remained in dire need of precipitation. More than 81% of the state is considered "abnormally" dry, including a small percentage in the first stages of drought, according to the most recent U.S. Drought Monitor.
Pacific Gas & Electric was tentatively scheduled to preemptively cut power to hundreds of thousands of residents of more than a dozen counties in Northern and Central California.
"The decision was based on weather forecasts indicating the potential for high winds and dry conditions leading to increased fire risk," PG&E said in a statement.
Contributing: Doyle Rice, USA TODAY; Ayano Nagaishi and Chris Coppola, Arizona Republic
This article originally appeared on USA TODAY: Los Angeles weather: Rain, flash flood watch hit southern California