Cloudy skies and a chance of light showers are expected Monday through most of Riverside County, forecasters said.
On Monday, the chance of precipitation in Riverside, Hemet and Temecula was predicted to be 20%, with winds remaining at 5 to 10 mph, according to the NWS.
Lowest maximum temperature records on Sunday were reported in parts of Riverside County.
The low in San Jacinto was 59, breaking the record of 63 set in 2023.
Showers moved into the Coachella Valley on Sunday with isolated thunderstorms in the Riverside County mountain communities and high deserts. The thunderstorms can create erratic and gusty wind conditions, and small amounts of hail.
Between 0.1 and 0.2 inches of rain in inland areas and up to a half-inch of rain in the mountains and deserts is expected Monday.
Snow levels will be around 8,000 to 9,000 feet Monday, with only the highest locations seeing any snow accumulation.
The NWS said a strong area of low pressure was moving into the region, bringing much cooler and windier weather across inland areas.
The South Coast Air Quality Management District issued an air quality alert due to harmful particle pollution levels from windblown dust. Areas affected by the alert included Indio, Palm Springs, Cathedral City, Palm Desert, Palm Desert Country, La Quinta an Coachella. The alert was effective until at least 2 p.m. Sunday.
Dry skies and a gradual warming trend was expected to begin Tuesday, with highs reaching the upper 80s in downtown Riverside by Thursday and the upper 90s in the Coachella Valley.