A large storm system that could bring several feet of snow to the West and blizzard conditions to the Northern Plains approached the West Coast Friday night, the start of a slow cross-country journey that will last all week. and through the following weekend, forecasters said on Saturday.
The storm system moved through the North Pacific on Friday and will reach California over the weekend, forecasters with the National Weather Service’s Weather Prediction Center said Saturday. The storm will continue to bring mountain snow and coastal rain to the west.
Winter precipitation will spread from the Great Lakes region to the northeast on Sunday. Heavy rain and thunderstorms could reach the south.
Computer models have given forecasters confidence in predicting the types of hazards that will occur early in the week as the storm sweeps across the central United States. This is what forecasters think is likely to happen.
Extreme winter impacts are very likely in the West this weekend.
The storm system began moving inshore late Friday, bringing strong winds to the California coast. Heavy rains at lower elevations could cause flooding.
In the mountains, however, that moisture has begun to fall as heavy snow.
“Impacts will spread from north to south with numerous winter weather advisories in effect,” the Weather Prediction Center said Saturday, adding that “the heaviest snowfall is expected for the Sierra Nevada,” with several feet expected.
Forecasters predicted “extreme impacts,” the most severe warning on the Weather Service’s winter storm severity scale, in the Sierra Nevada this weekend.
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In the Sierra mountain region, snow was falling at a rate of six inches per hour as of Saturday afternoon, according to the California Department of Transportation. “Travel is difficult or impossible with blurry conditions”, the department said on Twitter.
A portion of Interstate 80 near the Sierra Nevada was closed Saturday afternoon due to snow, creating “nearly zero visibility” on the highways, the Department of Transportation said in Twitter. After reports of “various vehicle turns”, the department said drivers were asked to turn around and there was no estimate of when the highway would reopen.
More than five feet of snow is expected in parts of the Sierra Nevada, forecasters with the Prediction Center wrote.
As this low-pressure system makes its way to land, it will connect with an atmospheric river, an area of moisture that flows through the sky like a river at a level in the atmosphere near where planes fly. The combination will allow snowfall totals to reach one to three feet on much of the higher ground.
Forecasters believe that blizzards will occur on the plains.
“We are increasingly confident that next week we will be dealing with a fairly significant snowstorm on the Northern Plains,” said Greg Carbin, head of forecast operations for the Weather Prediction Center.
The system will move out of the Rocky Mountains and begin to strengthen, increasing the possibility of heavy snow and very strong winds through Wednesday in the Northern Plains. Winter blast is possible from Colorado, including Denver, and northeast through the Northern Plains. Across the Dakotas, it’s likely at least a foot, Carbin said.
“There is the potential there for some really impressive numbers,” he added, as he expects this storm system will likely slow down.
Snow in the Central Rockies and Arizona mountains could reach a foot Sunday night.
Severe storms, possibly with tornadoes, are expected in parts of the South.
Severe storms, possibly capable of producing tornadoes, appear highly likely to form Tuesday in an area from eastern Texas through Arkansas, Louisiana and much of Mississippi, said Bill Bunting, chief of forecast operations at the Center for Storm Forecast.
“Most fall and winter severe weather events tend to have several characteristics in common, including a low pressure system near or north of the area of concern, an increasingly humid flow of air from the southern Gulf of Mexico moving north ahead of the event and a cold front moving east into the area,” explained Mr Bunting.
“A similar configuration is expected early next week,” he said, “giving us confidence regarding the potential for a focused area of severe thunderstorms and possibly tornadoes.”
Tornadoes are not uncommon this time of year, but they are less likely than in the spring and early summer.
“We average four days in December per year with at least one EF1” — rated on a scale of 0 to 5 damage per tornado — “or stronger tornado,” said Harold Brooks, principal scientist at the National Storm Laboratory. severe. part of the National Oceanic and Atmospheric Administration. “There are about 100 days with an EF1 or stronger tornado during the year.”
Severe winter storms like those forecast next week may be more dangerous than those that form during the peak severe weather season in May and June.
“Because the days are shorter,” Mr. Brooks explained, “they are more likely to happen after dark,” he said of the storms. This “makes them more dangerous” because people in danger can’t spot them when they get close, he said.
“They are also more likely to occur in the Mid-South and Southeast United States, which have a higher rural population density than the Plains and have a higher fraction of manufactured housing and poverty,” he added. “Therefore, the impacts may be greater.”
Snow is expected in the northeast.
Some snow is expected for southern New England, the interior Northeast and the central Appalachians on Sunday, forecasters said Saturday.
“Moderate snow totals are possible 3 to 4 inches inland for higher elevation locations like the Berkshires and Catskills, and 1 to 2 inches further south toward central Pennsylvania,” the forecast said.
Rain and snow showers are expected in inland northeast New Jersey, the lower Hudson Valley, and southern Connecticut by Sunday night. New York City could see snow on Thursday.
april rubin Y eduardo medina contributed reporting.