Intense rain will bring the possibility of flooding, mudslides, and debris flows to the region on Thursday. Meteorologist David Biggar has the evening forecast for Wednesday, February 12, 2025.
What to Know
- The most significant rain of the season in Los Angeles arrives this week.
- The brunt of the storm will bring widespread rain starting Thursday morning with peak intensity expected later in the day.
- A flash flood watch goes into effect for much of the region Thursday.
- Heavy downpours could trigger slides on hillsides stripped of vegetation by Southern California wildfires.
Flash flood watches will go into effect Thursday for Los Angeles and widespread parts of Southern California as a powerful storm brings significant rain to the region.
Scattered light showers will spread across the area Wednesday before the flash flood watches that start Thursday morning and continue through the night for most of the Los Angeles area. High rainfall rates could trigger flash flooding and slides in vulnerable burn scar areas, such as Altadena and Pacific Palisades.
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Rainfall timeline
The brunt of the storm will arrive Thursday, with widespread rain likely to impact the area for about 36 hours. Pockets of steady rain are possible with moderate to heavy rainfall, especially in mountain communities.
Rain will ramp up in the afternoon as the system moves from west to east through the evening and overnight. That period will bring the highest risk of flooding problems and debris flows in wildfire burn scar areas.
"Recent burn areas from the Palisades (Pacific Palisades), Hurst (Sylmar), Kenneth (West Hills), and Sunset (Hollywood Hills) fires are at a higher risk of debris flows and water runoff that may contain hazardous substances," the city of Los Angeles said in a statement. "Additional safety messages may be directed at these neighborhoods… Get ready and take extra precautions, especially if you are in an area that was impacted by the recent wildfires."
A flash flood watch goes into effect for much of the region at 10 a.m. Thursday through Thursday night. A flash flood watch indicates conditions that could lead to flash flooding. A flash flood warning, which could be issued during the storm, indicates flooding is happening or imminent.
"We're going to see rain pick up throughout the day, starting in the morning," said NBC4 meteorologist Shanna Mendiola. "Wet commutes to start. Very wet commute for your evening."
The rain will turn to showers on Friday, decreasing that afternoon.
- Wednesday: Steady light to moderate rain and mountain snow.
- Thursday morning: Widespread rain, some showers on the heavier side.
- Thursday midday and into evening: Peak rain intensity, highest risk of flooding problems and burn scar debris flows. Gusty winds are in the forecast.
- Friday: Lingering showers and mountain snow.
The storm could drop 1.5 to 3 inches across much of the region, with more than 3 to 6 inches in the coastal foothills and mountains.
Snow levels will be at about 5,000 feet Wednesday, rising to 7,000 feet Thursday then falling back to about 5,000 feet. Higher elevations could see several feet" of snow.
High temperatures will be in the 50s each day of the storm, which is about 5 to 10 degrees below normal./video
The region has been under severe to extreme drought conditions after a dry start to the wet season in Southern California. After two seasons of above-average rainfall, a months-long dry spell left hillsides covered in dry brush, providing fuel for wildfires.
The average annual rainfall in downtown LA is abou 14.25. In the 2022-2023 wet season, the region had 28.40 inches of rain followed by 25.19 inches of rain in 2023-2024. So far in this season, downtown LA is well below average.
