The dry, warm weather that has bathed the Southland for the past few days is about to end, with a pair of storms expected to hit the area and bring significant rainfall to the region.
The first storm system is expected to arrive in the area Wednesday night, with the brunt of it arriving early Thursday morning in Los Angeles County.
“The storm door opens again later Wednesday with rain expected to spread across the entire area by Thursday morning,” according to the National Weather Service. “This first system is a fairly quick moving one but has a strong upslope component that will enhance rain rates, especially in the foothills and mountains. But models also indicate some instability with this system so isolated thunderstorms are possible, especially over and near the coastal waters.”
Forecasters said rain could fall at a rate of a half-inch per hour, with some isolated areas seeing a rate of three-quarters-of-an-inch per hour.
“So there will likely be typical roadway flooding across the area but overall not expecting any significant flooding problems,” according to the NWS.
Snow levels will drop to about 6,000 feet by Thursday afternoon, with “several inches of snow” likely in higher elevations. Strong winds will also accompany the storm system, with gusts up to 50 mph possibly in mountain areas.
A winter storm watch will be in effect from late Wednesday night through Thursday evening in the San Gabriel Mountains and in the Golden State (5) and Antelope Valley (14) freeway corridors. Forecasters said up to 18 inches of snow could fall above 7,000 feet, with 6 inches possible at 6,000 feet “and a dusting to 3 inches between 4,500 and 6,000 feet.”
Widespread rain is also expected in Orange County, where forecasters issued a flood watch that will be in effect from Thursday morning through Friday morning. A high wind watch will also be in effect on Thursday, while a high surf advisory will be in place from 2 a.m. Thursday through 6 a.m. Saturday.
Forecasters said Orange County beaches could see waves of 4 to 6 feet, with some as high as 8 feet.
In Los Angeles County, a high surf advisory will also be in effect from 2 a.m. Thursday through 6 a.m. Saturday, with west-facing beaches possibly seeing waves peaking at 8 to 12 feet.
Rain is expected to taper off Thursday night in most of the area, with generally dry conditions expected through Saturday. Forecasters said some snow will still be possible as low as 4,000 feet, meaning a slight possibility of some accumulation along the Grapevine stretch of the Golden State (5) Freeway.
A second storm system is expected to reach Southern California sometime Sunday, beginning a “lengthy storm cycle” that could bring widespread rain totals of 2 to 4 inches in lower elevations, and possibly twice as much in south-facing mountains.
“Significant hydrologic issues are a strong possibility next week, including rock and mud slides in the mountains and flooding of small streams and rivers,” according to the NWS. “And based on the latest ensembles, some chances for flooding of the larger rivers and streams.”
Another 2 to 4 feet of snow is also possible at elevations over 6,000 feet, with some accumulations possible as low as 4,000 feet by late Tuesday into Wednesday of next week.