Deep snow fell in northern Utah overnight, closing schools in Cache and Box Elder counties, including Utah State University. The slow-moving storm reached Salt Lake City later Monday morning.
Utah Highway Patrol spokesman Doug McCleve, Salt Lake City, said Davis, Weber and Box Elder counties were getting "hammered" by a series of minor accidents.
Near Layton Hills Mall, a big accident happened about 10:30 p.m. on I-15. Several heavy vehicles were involved.
Another serious accident was reported about 9:30 a.m. near the same area. A semitrailer truck jackknifed on I-15 northbound at Roy. The truck hit a couple of cars, but it was not known by press time whether anyone was seriously injured. The accident closed northbound lanes.
U.S. 40 from the I-80 freeway to Heber City was closed because of dangerous snow conditions.
Highways were snow-packed from Brigham City north, said UHP spokesman Lt. George Chino, Brigham City. Snow was measured at 2 feet in Tremonton, Box Elder County.
In Brigham City, about 8 inches fell in one hour, Chino added.
A dense blanket of flakes and fog descended on Salt Lake City, drastically cutting visibility. Fortunately for commuters, the heaviest snow began hitting after the morning rush hour. But it was still bad enough that by midmorning, it had caused 15 accidents.
Fourteen of these were noninjury, but one required hospitalization. The injury was not believed life-threatening.
The Utah Avalanche Center issued an avalanche warning for the region from Spanish Fork Canyon to the Idaho border.
"Heavy snowfall and strong south to southwest winds overnight have created dangerous snowpack conditions. A widespread natural avalanche cycle is expected today," said the warning.
"It would have been a mess if we would have gone ahead and proceeded with school," said John DeVilbiss, spokesman for USU, which closed for the day for the first time in a decade.
Logan's total overnight was 17 inches. That was enough to close city offices and all schools throughout Cache Valley. But the snow continued.
By about 9 a.m., the Logan vicinity was "probably approaching 2 feet," said Chris Brenchley, meteorologist with the U.S. Weather Service in Salt Lake City.
The Weather Service issued a heavy snow warning for southwestern Wyoming and the Wasatch Mountain Valleys to continue through Monday morning. "Total accumulations of 8-18 inches are expected in this warning area," says the statement.
Brenchley said in Utah, "the farther north you go" the worse the storm was.
"The band of heavy snow sat up over northern Utah north of Ogden and up toward Logan all night, and it really dumped quite a bit of snow up there," he said. Clarkston, Cache County, reported 24 inches.
Ogden's snow measured 6 inches in the morning, and Davis County residents received 2-3 inches. But the snow was continuing to fall.
In Logan, snow began Sunday morning. The heavy snowfalls began in the afternoon and overnight.
Salt Lake City's levels were expected to be 2-6 inches on Monday and more overnight. East-bench neighborhoods would find deeper accumulations, valley floors less.
Additional snow was possible on Tuesday because the storm has been "such a slow mover," he said.
The Park City area had between 6 inches and a foot, while 2 feet of snow socked Big and Little Cottonwood canyons, limiting access to vehicles with chains or four-wheel drive.
Brighton Ski Resort in Big Cottonwood had 2 feet as of Monday morning. "It's still snowing pretty hard up there," he said.
Putting the finishing touch on the winter experience, temperatures were expected to be frigid. Highs throughout northern Utah were projected in the upper 20s through Wednesday.
Only scattered snow showers were expected for the Salt Lake area by Tuesday. The forecast for Wednesday called for partly cloudy skies and a few mountain snow showers.
Contributing: Toby Hayes.