National Weather Service United States Department of Commerce
Click a location below for detailed forecast.

Last Map Update: Sun, Feb. 18, 2018 at 3:40:10 am PST

National Weather Service San Francisco Bay Area, CANational Weather Service San Joaquin Valley, CANational Weather Service Las Vegas, NV
National Weather Service Honolulu, HIZoom

National Weather Service NWS Phoenix
National Weather Service Honolulu, HINational Weather Service San Diego, CANational Weather Service San Diego, CA

A very cold low pressure system will dive southward from Western Canada through to California Sunday into Monday. At this time, it appears that the system will take a mostly over-land trajectory with the best moisture and upslope flow focused on the north facing slopes. This system has the potential to bring the coldest air we have seen so far this winter season, with snow levels potentially falling as low as 1500 feet on Monday. With this storm falling over the holiday weekend, there could be significant travel impacts with possible road closures and delays. Low elevation mountain roadways that could be impacted by snow showers, icy roads, and strong winds include Interstate 5 near the Grapevine, Highway 14 through Soledad Canyon, and Highway 33 above Ojai. With such low snow levels expected, there is also a slight chance of snow showers on Monday across the valleys and foothills down to 1500 feet which could impact Cuesta Pass and San Marcos Pass. The strongest winds will occur in the mountains with gusts between 50 and 60 mph.
The coldest air mass so far this season will bring the potential for widespread frost and freeze conditions across Southwest California Monday night and again Tuesday night. Extremely cold temperatures between 15 and 25 degrees will be possible across the Antelope Valley, Cuyama Valley, and San Luis Obispo Interior Valleys during this cold snap, however all of those locations have already had 2 or more hard freeze episodes this season. A hard freeze will be possible across the Santa Ynez Valley, Central Coast, and Ojai Valley where temperatures could fall into the mid 20s in coldest locations. Wind sheltered portions of Los Angeles and Ventura county valleys could see temperatures at or below 32 degrees. A hard freeze can cause significant damage to plants and crops. People and pets can suffer from hypothermia due to prolonged exposure.


Text Product Selector (Selected product opens in current window)