Storm system expected to bring up to 1-2 inches of rainfall
Another atmospheric river storm that formed in the Gulf of Alaska and has been tapping into subtropical moisture from the central Pacific was expected to bring more rain, mountain snow, and winds to the Mother Lode Monday night to Tuesday, forecasters in Sacramento said Monday afternoon.
The storm system was described as moderate-strength compared to the major storm that brought record rainfall to Sonora and other Central Sierra locations in late October.
San Andreas, Angels Camp, Columbia, Sonora, Twain Harte, and Yosemite National Park could all receive up to 1 to 2 inches of rain Monday night and Tuesday.
Ebbetts, Sonora, and Tioga passes on Highway 4, 108, and 120 are all already closed due to snow. All three passes could get another foot to 18 inches of additional snow Monday night and Tuesday.
There was a winter weather advisory in effect for most of the Central and Northern Sierra Nevada range, including the Stanislaus National Forest in Calaveras and Tuolumne counties. Winds could gust 25
to 30 miles per hour in foothills towns, and up to 45 mph and stronger in the mountains.
“Snow levels, we're looking at 5,500 to 6,500 feet late (Monday night), and rising overnight to 8,000 to 8,500 feet by mid-morning Tuesday,” Katrina Hand, a National Weather Service meteorologist in Sacramento, said Monday afternoon in a phone interview.
Hand said the rest of this week is expected to be mostly sunny and clear in the Mother Lode, with daytime highs in the 60s and overnight lows in the 40s along the Highway 49 corridor in Calaveras and Tuolumne counties.
“This one is definitely not as strong as the big one we saw in October,” she said, referring to the bomb cyclone-generated weather system that brought record rains to Sonora and other places on Sunday, Oct. 24. “It originated in the Gulf of Alaska and out of the Pacific northwest, and it moved out the central Pacific, where it's tapped into a little subtropical moisture. It will be similar to other atmospheric river storms. Not as strong as that big one, but this is bringing some widespread rainfall.”
The latest storm was expected to track south of Interstate 80 and Highway 88, to bring more early winter precipitation to Alpine, Calaveras, and Tuolumne counties, as well as Yosemite, Hand said.
A period of heavier rain was expected from 8 p.m. Monday to early Tuesday morning. Rain rates are unlikely to be high enough to impact burn scars, including the Airola Fire and Washington Fire burns, forecasters in Sacramento said earlier Monday.
The Mother Lode and Central Sierra regions have received scant precipitation since the Oct. 24 storm, when a total of 6.6 inches of rain and snow had been measured in the Stanislaus River and Tuolumne River watersheds since the current water year began Oct. 1. As of Monday, that 6.6 inches was still equivalent to 217% of average for the date Nov. 8.
Major reservoirs in Calaveras and Tuolumne counties remained less than half full as of Monday. New Melones, the fourth-largest capacity reservoir in the Golden State, was 35% full, and Don Pedro, the state's sixth-largest capacity water storage facility, was 49% full, according to the state Department of Water Resources.
Scientists say California still has a long way to go to get out of the current drought situation. In spite of record rains and significant snowfall in late October, nearly all of Calaveras and Tuolumne counties, most of the Central Sierra, and more than 38% of California remained in the most dire drought category, exceptional. More than 83% of the state was in severe drought before the approaching storm arrived in the Mother Lode.
Pacific Gas and Electric Co. distributed safety tips in advance of the expected wet and windy weather over much of PG&E'S coverage area. The utility tries to serve more than 16 million people across more than 70,000 square miles in central and northern California.
Communications staff and meteorologists with PG&E shared the following weather safety tips Monday:
• Be sure to have flashlights or battery-operated lanterns with fresh batteries in case of power outages.
• Avoid using candles due to the fire risk.
• Keep cell phones, tablets and other devices charged in case of a power outage.
• If you have a landline, try to have a corded telephone that doesn't require electricity available, or a battery-backup phone system so you can receive and make phone calls during a power outage.
• Put away or secure outdoor furniture and cushions to prevent wind and rain damage.
Anyone who sees downed power lines or downed power poles should call 911 and stay away. To report power outages and to get updates on outages status, call (800) 743-5002 or visit www.pge.com/outages.