Another round of heavy rainfall will envelope the Inland Empire beginning Thursday and continuing into Christmas Day, as back-to-back fronts sweep in from the north, forecasters said Tuesday.
According to the National Weather Service, a trough of low pressure hanging off the west coast of Canada will gradually roll across California, dragging “a lot of moisture” in from the eastern Pacific.
The first signs of wet weather will be late Wednesday night, but more significant rainfall will begin midday Thursday, with precipitation stretching across the entire region down to the Mexican border, according to prognostication charts published by the NWS.
“We are expecting significant precipitation to fall as mostly rain, even over the mountains, late Thursday into Friday,” according to the agency. “The amounts forecast will be a blend of the extremes, but there will be a chance for greater amounts, since we have the contribution of a moderate atmospheric river for at least a portion of the event.”
According to forecasters, anywhere from 0.75 to 2.75 inches are possible in areas over a 36-hour period.
“Greater rainfall rates and totals are quite possible and would have local flooding impacts, especially on Friday,” according to the NWS.
Snow levels are predicted to remain above 6,000 feet Thursday and Friday. However, as another trough of low pressure trails in Friday night into Saturday morning, freezing levels may drop, meteorologists said.
The trailing low is not expected to generate the intense downpours that will likely be produced by the first one, but scattered precipitation is forecast to linger through the weekend, according to analyses.
“Count on cool conditions, lots of clouds, and fog in the mountains, through the Holiday weekend and into next week,” according to the Weather Service.
High temperatures in the Riverside metropolitan area will be in the upper 60s Wednesday, with lows in the upper 40s, but Thursday, Friday and Saturday, highs will hover in the mid 50s, with lows in the mid 40s, according to forecasters.
In the Coachella Valley, the high Wednesday will be just above 70, but for the remainder of the week, the mercury won’t get out of the mid 60s, will lows around 50. In the Temecula Valley, the high will peak at 70 Wednesday, followed by a temperature range of 45-56 degrees from Thursday to Saturday.