The National Weather Service has issued a flood watch for Southern California, signaling potential heavy rain through Friday. The warning, effective from 10 p.m. Thursday until Friday morning, encompasses much of Los Angeles County. As the storm progresses, increased precipitation may bring localized flooding.
Storm Details and Timing
Forecast models indicate a severe weather event poised to affect L.A. County. This storm could rotate counterclockwise over southern regions on Thursday night and Friday morning, which raises the potential for small tornadoes. Heavy rainfall is anticipated, with rates reaching up to 1 inch per hour in certain areas.
Key Forecast Parameters
- Flash flood watch active from midnight Friday through Friday evening in eastern Riverside and Imperial Counties.
- 10-20% chance of thunderstorms in Los Angeles and Ventura Counties.
- 20-40% chance of thunderstorms in Orange County, San Diego County, and the Inland Empire.
- Wind gusts may reach 50 mph during storms.
Conditions could evolve unpredictably over the weekend, primarily due to a “cut-off low” storm. This system is less influenced by the jet stream, making predictions about rain and snow challenging.
Rainfall Records and Impacts
This November has already marked significant rainfall milestones. Santa Barbara Airport reported its wettest November since records began in 1941, with 8.42 inches recorded. Previously, the wettest November recorded there was in 1965, with 6.92 inches.
- Downtown Los Angeles: 3.48 inches in November, nearly ten times the usual amount for this period.
- Overall, 4.89 inches of rain have fallen since the water year began on October 1, significantly above average.
- Orange County’s John Wayne Airport: 3.89 inches, quadrupling the expected amount.
- San Diego International Airport: 2.93 inches, three times the average for the season.
Long-term Effects on Fire Season
Forecasters note that 3 to 4 inches of rain in lower elevations can effectively end the high fire season in Southern California. With current rainfall, the region is in a better position to withstand potential fire risks as autumn progresses.
Looking ahead, areas such as Anaheim, Irvine, and Oceanside are forecasted to receive between 1 to 1.5 inches of rain. Meanwhile, rain in areas like San Diego and Riverside may range from 0.5 to 1 inch. Joshua Tree National Park could face 1.5 to 2 inches of rainfall.
While rain is expected to linger in L.A. County through Saturday morning, the weather will clear up for the rest of the Thanksgiving weekend, with cooler temperatures and dry conditions anticipated.
No significant snowfall is expected along the Grapevine in the Tejon Pass, which sits at 4,144 feet, providing some relief for travelers in the area.
