By Reginald Stanley. Posted April 4, 2020, 11:12 AM.

A strong, cold, moisture-laden low pressure system is forecast to slowly move across the state over the course of next week, with rain forecast every day from Sunday night through Thursday. A slight chance of thunderstorms is included for Tuesday night through Wednesday night due to instability.

Rain is expected to be heavy at times. Snow levels are predicted to fall to approximately 4,500 feet above sea level, with particularly heavy accumulations expected above 5,500 feet. This will impact travel along the Interstate 15 and Interstate 5 freeway corridors, in the Cajon Pass and north of Los Angeles. Interstate 8 near Alpine may be affected to a lesser extent. Across the Inland Empire, accumulated precipitation totals are predicted to fall between 2 and 2.5 inches through next Thursday, with higher amounts in San Bernardino, Highland, Redlands, Yucaipa, Calimesa, Beaumont and the vicinity also possible. Simi Valley, the Los Angeles Basin and much of San Diego County are not expected to be hit quite as hard, with less than 2 inches of rain predicted for those areas. The deserts may see relatively significant precipitation from this storm system as well, with between 0.5 and 1.5 inches predicted for the high desert regions (including Pinon Hills), and up to 0.7 inches in the low deserts.

Due to the potentially high impact of winter weather on travel in the Riverside, San Bernardino and Los Angeles County mountains, the National Weather Service has issued a Winter Storm Watch for mountains above 5,500 feet from 11 PM Sunday night through 5 AM Thursday morning.