An end-of-winter storm series descends on the Inland Empire this week bringing rain to the valleys and snow to the San Bernardino Mountains.
Ashley Ludwig, Patch Staff
PALM DESERT, 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.
Find out what's happening in Palm Desertfor free with the latest updates from Patch.
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.
In Palm Desert, the National Weather Forecast for the week is as follows:
MondaySunny, with a high near 81. East wind around 5 mph.
Monday NightMostly cloudy, with a low around 53. Calm wind becoming west around 5 mph after midnight.
TuesdayA chance of showers. Partly sunny, with a high near 68. Calm wind becoming southeast around 5 mph in the afternoon. Chance of precipitation is 50%. New precipitation amounts of less than a tenth of an inch possible.
Tuesday NightA chance of showers before 11pm. Mostly cloudy, then gradually becoming mostly clear, with a low around 50. Calm wind. Chance of precipitation is 30%.
WednesdayMostly sunny, with a high near 71. Southeast wind 5 to 10 mph, with gusts as high as 20 mph.
Wednesday NightA chance of showers after 11pm. Increasing clouds, with a low around 50. Chance of precipitation is 30%.
ThursdayShowers. High near 61. Chance of precipitation is 100%.
Thursday NightA slight chance of showers before 11pm. Partly cloudy, with a low around 43.
FridayMostly sunny, with a high near 64.
Friday NightPartly cloudy, with a low around 47.
SaturdaySunny, with a high near 72.
Saturday NightMostly clear, with a low around 51.
SundayMostly sunny, with a high near 75.
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