As of Monday afternoon, weather-related closures and cancellations included all Tuolumne County offices on Tuesday, and cancellation of a Tuolumne County Board of Supervisors meeting that’s been rescheduled to 9 a.m. Feb. 12. As of 3:30 p.m. Monday, staff with the Tuolumne County Office of Education said they planned to remain open and advised people to check websites for individual schools for updates. A Tuolumne County Board of Education meeting scheduled at 4 p.m. Monday was postponed. In addition, a 5 p.m. Monday meeting of the Sonora City Council was postponed.

A freezing cold winter blast could bring four to seven inches of snow down to 1,500-foot elevations, which includes much of Sonora, Columbia and other Mother Lode foothill towns by Tuesday morning or Tuesday afternoon, forecasters say.

Wet snow was falling in downtown Sonora as of 3:30 p.m. Monday.

The potential for whiteout conditions and below-freezing temperatures comes on the heels of a warmer atmospheric river storm system that dumped more than 5 inches of rain since Friday in parts of Calaveras and Tuolumne counties, and more than 6 inches in Yosemite Valley.

A blizzard warning is in effect for the western Sierra Nevada slope down to 5,000-foot elevations including Arnold, Cold Springs and Pinecrest through 10 p.m. tonight, and a winter storm warning for heavy snow above 1,500 feet elevations is on through 4 p.m. Tuesday.

Tuolumne County sheriff’s staff warned residents to prepare ahead of the cold winter storm. They recommended stocking up on extra food and water, including things that don’t require refrigeration in the event of outages.

As of Monday evening, closed roads in Tuolumne County included Red Hills Road in the Chinese Camp area, Sims Road in the Jamestown area, and Bell Mooney Road near Woods Creek outside Jamestown. Chains or snow tires were required on Highway 108 from East Twain Harte up to the closure east of Strawberry, and on Highway 4 from Arnold east to the closure up in Alpine County. Chains were also required on vehicles in Yosemite National Park.

“This next system appears to be bringing the heaviest precipitation from Highway 50 southward,” Eric Kurth, a National Weather Service meteorologist in Sacramento, said Monday in a phone interview.

Heavier snow was expected to come from midnight Monday to 4 a.m. Tuesday, with lighter snow through late Tuesday morning and perhaps even the afternoon, with another inch or two possible before the storm quits, Kurth said. The greatest chances for low foothill snow accumulation are expected late Monday into Tuesday morning.

“We’ll see some pretty significant snow down to 1,500 feet,” Kurth said. “We could see lighter accumulations down to 1,000 feet. Low snow could mean potential power outages.”

Monday’s rain and snow came with fog in some areas of Tuolumne County, including Columbia. Overnight lows for Sonora and Columbia and Angels Camp were expected to fall to 32 degrees Fahrenheit early Tuesday, 23 early Wednesday, and 25 early Thursday.

Wintry driving conditions contributed to at least one crash Monday morning up Highway 108 near Confidence Road. Before 9 a.m. there was a gray sports utility vehicle reported off the road and down an embankment, with icy road surfaces in the area and a crash scene described as inaccessible due to snow. CHP personnel reported receiving multiple calls about the vehicle.

Also Monday morning, there was a downed tree or tree limb in the road near Parrotts Ferry Road and Porcina Way outside Columbia. A tree or tree limb also came down Monday across Deardorff Road in Railroad Flat, said Sgt. Rachelle Whiting with the Calaveras County Sheriff’s Office. A sinkhole was reported on Main Street in Mokelumne Hill. Road crew leaders were busy trying to keep up with storm damage, Josh Pack with Calaveras County public works said Monday afternoon.

Issues Monday and over the weekend in Calaveras Countyvincluded three trees down into power lines and four trees down on county roads, Pack said. O’Byrnes Ferry Road was closed Sunday night due to a fallen boulder on the Tuolumne County side. At Pool Station Road, high water overtopped of the bridge 4 to 5 inches deep. Road crews were on 24-hour shifts over the weekend and will continue working until inclement weather has passed, Pack said.

Crashes that occurred during the weekend weather included one non-injury crash Sunday morning on Little John Road in Copperopolis, when a vehicle went off the road and struck an embankment, CHP staff in San Andreas said.

Sonora area CHP personnel investigated nine crashes Saturday and Sunday in Tuolumne County, as well as a mudslide Sunday on O’Byrnes Ferry Road. The slide closed the road temporarily and O’Byrnes Ferry Road was open again Monday, said CHP Officer Michael Huddleston in Jamestown.

On Sunday, a tree temporarily blocked one lane near Draper Mine Road and Highway 108 east of Mono Village, according to the Tuolumne County Sheriff’s Office. A rockslide also partially blocked the roadway at Cottonwood Road and Buchanan Mine Road near the bridge down in the North Fork Tuolumne River canyon.

A temporary closure on Old Priest Grade was also due to a mudslide, Tanya Allen, engineering manager with Tuolumne County’s community resources agency and roads division, said Monday. The closure was lifted Monday afternoon and Old Priest Grade was open again for the time-being.

As of Monday morning, rainfall totals for the preceding 72 hours in Calaveras and Tuolumne counties included 3.82 inches at Railroad Flat, 3.49 inches west of Angels Camp, 5.03 inches at Avery, 4.03 inches at Stanislaus Powerhouse below Hathaway Pines, 3.49 inches at New Melones Dam, 4.13 inches in Columbia, 3.76 inches at Telegraph Hill above Sonora, 5.36 inches at Pinecrest, 3.14 inches at Moccasin, 3.32 inches at Groveland, 5.76 inches at Cherry Reservoir, 4.37 inches at Hetch Hetchy, and 6.49 inches in Yosemite Valley.

As of Monday the Mother Lode’s primary watersheds, including the Stanislaus River and Tuolumne River basins, had received 5.1 inches of precipitation since Friday, and 23.1 inches since the current water year started Oct. 1, according to a five-station index that includes Calaveras Big Trees and Hetch Hetchy. The totals equated to 108 percent of average for the date Feb. 4.

No major Mother Lode rivers were at or approaching flood stage Monday, according to California Nevada River Forecast Center.

As of Monday afternoon, weather-related closures and cancellations included the announced closure of all Tuolumne County offices on Tuesday, and cancellation of a Tuolumne County Board of Supervisors meeting that’s been rescheduled to 9 a.m. Feb. 12. As of 3:30 p.m. Monday, staff with the Tuolumne County Office of Education said they planned to remain open and advised people to check websites for individual schools for updates. A Tuolumne County Board of Education meeting scheduled at 4 p.m. was postponed. In addition, a 5 p.m. Monday meeting of the Sonora City Council was postponed.

Contact Guy McCarthy at gmccarthy@uniondemocrat.com or 588-4585. Follow him on Twitter at @GuyMcCarthy.

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