A flood warning has been issued by the National Weather Service for Pohono Bridge, which spans the Merced River in Yosemite National Park.
The weather service said flood stage could be reached Saturday morning, when the river is forecast to rise to 10 feet. It will then crest at 15 feet by early afternoon, according to the latest forecasts.
Yosemite Valley was to be closed to visitors at 5 p.m. Friday because of the flooding threat. No hotel or camping guests were to be allowed to remain in the valley due to the storm, which is expected to melt snow in the mountains above the valley. That runoff will raise the Merced River's water level.
Should the river reach a flood stage of 12.5 feet, the two main roads in the valley — Northside and Southside drives — become flooded and closed to traffic, the weather service noted.
At levels below 12 feet, portions of the North Pines and Lower Pines campgrounds get flooded.
Besides Yosemite, the foothill areas of Fresno, Madera and Mariposa counties are under a flood watch through Sunday morning.
Local flash flooding may occur as a result of heavy rain and snow melt, the NWS said.
The weather service said rises in the San Joaquin and Kings rivers may also occur from the runoff.