Rain Returns To Southwest RivCo: What To Expect This Week

TEMECULA, CA — The end-of-winter storm series will continue this week across the Inland Empire, producing appreciable rain and snowfall, windy conditions, and possibly thunderstorms, according to the National Weather Service.

Forecasters said two "atmospheric rivers" will course over Southern California, the first arriving Tuesday and the second passing Wednesday night and Thursday.

"Showers could develop as early as Tuesday morning, with increasing chances of heavier rain in the afternoon and evening," the NWS said in a statement. "For the Inland Empire, rainfall totals of .1 to .25 inches are possible, with the potential for locally higher totals if a heavier rainfall band develops. Snow levels will be 5,000 to 6,500 feet, with 1-2 inches of snow possible (in the San Bernardino Mountains)."

The Weather Service cautioned that "periods of gusty south winds are expected Tuesday, with peak gusts of 30 to 40 mph for the mountains and deserts."

The first system will make a quick exit to the east in the predawn hours on Wednesday. However, its sequel will soon follow, anchoring over the region late Wednesday night.

The NWS stated that the second upper-level low-pressure trough "is expected to be colder than the Tuesday system.

"The cold nature of the storm aloft also increases the chances of thunderstorms across the area, leading to the potential of locally heavy rain and flooding," the agency said. "The chances for exceeding 2 inches are 70 to 90% for the mountains and 40 to 50% for portions of the valleys. There is even a 30 to 50% chance of rainfall exceeding 4 inches of rain on the coastal slopes of the San Bernardino Mountains."

According to meteorologists, snow levels will initially hold above 6,000 feet, but drop to as low as 3,000 feet by Thursday night or Friday morning, when the disturbance spins eastward,

"Estimated snowfall totals above 6,500 feet are 8 to 12 inches, with locally up to 24 inches possible above 7,500 feet," the NWS said.
Clear and mild conditions are forecast for the weekend.

High temperatures in the Riverside metropolitan area will be in the mid-70s on Monday, but the mercury will barely exceed 60 on Tuesday, with lows in the upper 40s. From Wednesday to Friday, the daytime temps will peak in the upper 50s, falling into the low 40s at night.

In the Coachella Valley, the high will hit 80 Monday but crest in the upper 60s Tuesday and Wednesday, maxing out in the low 60s Thursday and Friday. Lows will generally hover in the upper 40s to low 50s for the week.

The temperature band in the Temecula Valley will closely parallel the Riverside metro, forecasters said.

Near Temecula, Murrieta and Lake Elsinore, the National Weather Forecast for the week is as follows:

Monday
Sunny, with a high near 72. Southwest wind 5 to 10 mph, with gusts as high as 20 mph.

Monday night
A slight chance of showers after 11pm. Mostly cloudy, with a low around 43. South wind 5 to 10 mph becoming light and variable after midnight. Chance of precipitation is 20%.

Tuesday
Showers. High near 58. Calm wind becoming south around 5 mph in the afternoon. Chance of precipitation is 80%. New precipitation amounts between a tenth and quarter of an inch possible.

Tuesday Night
A chance of showers, mainly before 11pm. Mostly cloudy, with a low around 44. Calm wind becoming south around 5 mph after midnight. Chance of precipitation is 50%. New precipitation amounts of less than a tenth of an inch possible.

Wednesday
A chance of showers. Mostly cloudy, with a high near 61. South wind 10 to 15 mph, with gusts as high as 25 mph. Chance of precipitation is 50%. New precipitation amounts of less than a tenth of an inch possible.

Wednesday Night
Showers, mainly after 11pm. Low around 43. Chance of precipitation is 90%.

Thursday
Showers. High near 54. Chance of precipitation is 100%.

Thursday Night
Showers likely, mainly before 11pm. Mostly cloudy, with a low around 35.

Friday
Partly sunny, with a high near 56.

Friday Night
A chance of showers. Mostly cloudy, with a low around 40.

Saturday
Partly sunny, with a high near 61.

Saturday Night
Partly cloudy, with a low around 41.

Sunday
Partly sunny, with a high near 66.