Rain could put a damper on Halloween festivities this weekend across Southern California as a potentially strong storm moves into the region, forecasters said.
Rain could begin as early as Friday, with forecasters predicting unsettled weather through Sunday. However, the timing and intensity of the storm remain uncertain, particularly for Halloween on Saturday, Oct. 31, according to the National Weather Service.
In Los Angeles and surrounding areas, forecasters said they have very high confidence that rain will fall over the weekend, though it remains unclear when the heaviest rainfall will arrive.
"There is very high confidence that it will rain during the weekend, but low confidence on onset timing and peak timing," NWS Los Angeles/Oxnard forecasters wrote.
Current forecasts call for about an inch of rain across much of the Los Angeles area, with higher totals possible in the foothill and coastal slope areas, according to the NWS. Forecasters said there is a 20% to 30% chance some areas could receive twice that amount.
In the Inland Empire and San Diego County, forecasters said increasing confidence suggests the most of the rain may hold off until Sunday, although occasional light showers could develop Friday or Saturday.
"There remains a lot of uncertainty in the details of the forecast this weekend, but there is increasing confidence that the bulk of the precipitation won't arrive until Sunday," National Weather Service San Diego forecasters wrote. "That being said, periods of on and off light showers may develop as early as Friday or Saturday."
Depending on the storm's path, rainfall totals Sunday could range from as little as a tenth to a quarter of an inch to as much as 1.5 to 2.5 inches, according to the National Weather Service.
The storm is also expected to bring gusty winds to mountains and deserts, along with a significant drop in temperatures.
Highs in Los Angeles and surrounding areas are expected to remain in the mid- to upper 60s through the weekend, according to the National Weather Service. Inland areas of San Diego, Riverside and San Bernardino counties could see temperatures 10 to 20 degrees below normal Saturday and Sunday.
Ahead of the storm, unusually high tides are already causing coastal flooding across Southern California.
On Monday, a record high tide of 8.02 feet was recorded in San Pedro, breaking the previous record of 7.93 feet set Jan. 10, 2005, according to the NWS. In Newport Beach, ocean water flooded streets in low-lying neighborhoods as tides reached 8.3 feet. Even higher tides are expected Tuesday.
Coastal flood warnings remain in effect through 1 p.m. Thursday for Orange and San Diego counties, while a coastal flood advisory covers portions of the Los Angeles County coastline.
Forecasters warned that flooding could affect roads, homes and businesses in vulnerable coastal areas. The weather service also warned of possible shoreline erosion during morning hours.
The high tides have already disrupted rail service, prompting Metrolink to suspend Orange County Line trains between Laguna Niguel/Mission Viejo and Oceanside through Friday.
More California News:
City News Service contributed to this report.
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