MOUNTAIN COMMUNITIES—The National Weather Service Hanford Office is predicting a significant storm system will begin to make inroads from the north on Saturday evening with light precipitation spreading down to Yosemite National Park (YNP) and as far south as Fresno County through Sunday afternoon.
Rainfall in the valley will generally only be a few hundredths to a tenth of an inch. Rain in the mountains will range from a quarter to three quarters of an inch. Snow levels will be above 9000 feet where up to 7 inches of snow is possible.
Sunday Night Into Monday
The upper low is expected to be off the Pacific Northwest coast on Sunday night and Monday with a moist westerly flow aloft digging down to central California. Precipitation rates are expected to increase Sunday night from north to south with periods of moderate to heavy precipitation. The low remains nearly stationary through Monday with precipitation continuing and being enhanced over the Sierra Nevada’s due to favorable conditions.
Tuesday And Wednesday
The low opens up into a trough on Tuesday and begins to shift inland with continued moderate to
heavy precipitation. The trough then exits to the east on Wednesday with diminishing light showers.
The Winter Storm Watch for the Sierra has now been upgraded to a Warning. The Warning begins at 4 PM Sunday from YNP (outside of the valley) to the upper San Joaquin River. Farther south, from the Upper San Joaquin River to the South End of the Upper Sierra Nevada’s, the Warning begins at 10 PM. Both of the Warnings end at 10 AM Wednesday.
The snow level will begin around 8000 feet on Sunday evening then lower to 6000-7000
feet overnight. Snow levels continue to lower to 5000-6000 feet on Monday, 4000-5000 feet Monday night and Tuesday, then 3000-3500 feet on Tuesday night and Wednesday. Total snow accumulations may reach 3 to 4 feet above 7000 feet, 2 to 3 feet from 5000-7000 feet, and 1 to 2 feet from 4000-5000 feet.
Rainfall in the Sierra Foothills is expected to range from 2 to 4 inches. Rainfall amounts in the San
Joaquin Valley is expected to range from 1 to 2 inches with the higher amounts favored across the eastern portions of the valley.