What to Know
- A storm that drenched Ventura County overnight is expected to bring more rain to LA County.
- Periods of rain are in the forecast into Friday.
- Rainfall rates were expected to decrease as the center of the storm moves out of Ventura County.
A storm fueled by an atmospheric river will bring several hours of rain, strong winds and the potential for flooding Thursday to Los Angeles County and other parts of Southern California -- and will continue delivering inclement conditions Friday, as well.
The storm caused significant flooding overnight as it moved into Ventura County. A flood watch was issued through late Thursday in Los Angeles County and Friday evening in Orange County as the slow-moving system delivers hours of rainfall to the region.
A brief tornado warning was issued overnight in Ventura County.
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Rainfall rates were expected to decrease as the center of the storm moves out of Ventura County and into Los Angeles County, but there will still be chances of large amounts of rain in a short period of time.
The storm was spinning off the coast of LA County early Thursday with moisture streaming up into Ventura County. The system will gradually spread east into Los Angeles and Orange counties, and the Inland Empire, where a flood watch runs until 4 p.m. Friday and a winter weather advisory will continue until 6 p.m. Thursday to 4 a.m. Saturday.
There will be a 20% to 30% chance of thunderstorms through Thursday night. As of 5 a.m., there was 1.06 inches of rain reported in Huntington Beach and 1.02 inches reported in Coto De Caza. There was 1.62 inches of rain reported in Upper Harding Canyon and 1.34 inches reported at Santiago Peak.
Snow levels are expected to remain above 6,500 feet, with several inches possible at elevations over 7,500 feet.
Daytime temperatures will remain in the 60s in the region for much of the week. Overnight lows will generally be in the upper 40s and lower 50s throughout the Southland, but will dip into the 30s in some parts of the mountains and high desert.
Thursday is the first day of winter and conditions will remain wet through the end of our week.
"We’ve got some rain that will continue, especially overnight tonight into our Friday," NBCLA forecaster Melissa Magee said. "It starts to fill in for everyone, so something to keep in mind if you’re out and about first thing on your Friday."
Some areas of SoCal may see a break in the rain Thursday night but the remainder of the storm is slated to creep into the region during the overnight hours.
"The center of the storm is still sitting offshore, so it’s not until tonight into our Friday that this sacks to our south and then sweeps inland," Magee said. "Once that happens, you’ll start to see those bands oversweep much of our region."
The brunt of the moisture will remain offshore around 11 p.m. Thursday. By 2 a.m. Friday, however, rain will be over much of Southern California and will become even more widespread for the Friday morning commute.
"We’ll start to see that rain that will continue moderate pockets as we go throughout the mid-morning hours, then we’ll have one more push of moisture that moves through by the afternoon," Magee said.
That rain will begin to depart east anywhere between 2 and 4 p.m. Friday. Lingering showers may remain in SoCal through Saturday but for the most part, it appears the storm will cooperate with the holidays and not put a damper on celebrations.
