Yosemite National Park planned to close all three highways leading into Yosemite Valley on Thursday evening, the most drastic step to confronting a storm moving into the region.
The National Weather Service in Hanford said the largest storm system so far in the young rain and snow season began hitting the central San Joaquin Valley around noon Thursday and was to last into Friday morning. Cities on the Valley floor were to get between 1 to 2 inches of rain, while foothill and mountain areas were to receive even more. There’s also a likely chance of flooding at the higher elevations and a slight chance for cities on the Valley floor.
Yosemite visitors were asked to leave by 4 p.m. and the road closure was set to start at 5 p.m. Thursday due to the threat of flooding in a stretch of the Merced River. Yosemite spokesman Scott Gediman said forecasters predict the flooding will happen between 11 p.m. and 2 a.m., and park officials will determine Friday morning when roads will open again.
Wawona Road (Highway 41) will be closed from Wawona to Yosemite Valley, Highway 120 will close at the Foresta Road Junction, and Northside Drive and Highway 140 are also affected. Authorities said they are not telling anyone to evacuate and will be putting up gates to ensure no one drives out the park under these conditions.
“Safety is our No. 1 concern,” Gediman said.
Gediman said a hard closure like this has not been conducted since March 2010.
Because this is a warmer storm system that originated in the tropics, the snow level remained fairly high. Snow was expected to fall above 8,000 feet on Thursday.
However, that was expected to change on Friday. The Weather Service predicts that snow levels could drop to 4,000 feet, which could cause trouble on the roads for anyone heading out on weekend trips that would take them over mountain passes. Meteorologists are paying especially close attention to the Grapevine and Interstate 5.
Two to four feet of snow was to fall in the Sierra through Friday morning, with highest peaks getting up to 6 feet, the Weather Service said.
Following the wet weather will be drier, colder air. Daytime highs are expected to drop to around 50 degrees by Saturday. Overnight lows this weekend will fall into the 30s in the Valley.