Another round of ‘atmospheric river’ storms to blast California with rain, snow, floods
Show Caption Hide Caption Road crews cutting down the use of salt AccuWeather’s Bill Wadell reports that road crews have been cutting down on the use of salt to clear the highways of snow and ice across the country this winter.
After a brief respite of quiet weather, another round of “atmospheric river” storms is forecast to slam into California over the next few days, dumping heavy rain and snow and raising fears of floods and mudslides.
“California is facing another multi-day siege of stormy weather for several days starting Saturday, which could result in the potential for flooding rainfall, landslides, heavy mountain snow, strong winds and coastal flooding,” said Weather.com meteorologist Linda Lam.
The storms come roughly a week after a strong atmospheric river unloaded as much as a foot of rain in the Los Angeles area.
This time, northern and central portions of the state could see the worst of the weather from the first storm over the weekend, while southern California, including the Los Angeles area, will see its most significant storminess on Monday from a second, stronger storm.
“The wet stretch of weather will lead to travel disruptions across the state in the air and on the ground,” warned AccuWeather meteorologist Elizabeth Danco.
Snow in the Sierra will be measured in feet
Snow in the Sierra Nevada will come in two parts: The first of two storm systems moves in Saturday followed by a more significant system Sunday night.
Saturday night’s snowfall will be measured in inches, but by Sunday start counting in feet, said meteorologist Matt Chyba with the National Weather Service in Reno, Nevada, the office that forecasts weather for the high Sierra.
According to Chyba, Saturday’s storm should leave about 6 inches in the mountains. But by Sunday night into Monday morning, snow could start falling at a rate of 2 to 3 inches an hour, leaving up to 3 feet in the higher elevations.
Anyone planning to travel through some of the region’s mountain passes, including Donner Pass, should prepare for the high risk of restrictions and closures as a result of the heavy snow, AccuWeather said.
The Sierra snow will be great news for ski areas and also for water resource managers, as it will add to what’s been a below-average Sierra snowpack so far this season.
Heavy rain in SoCal could trigger flooding
At lower elevations in southern California, the fear is primarily about heavy rain and potential flooding from Sunday’s storm. “This system has the potential to bring high impact weather and flooding concerns to the area through Tuesday evening,” the weather service office in Los Angeles said.
According to the weather service, the storm will bring periods of moderate to heavy rain (2-5 inches and 4-8 inches in some mountains and foothills), strong south to southeast winds, along with the potential for flooding, rock slides and mudslides, and possible power outages.
By Monday and Tuesday, creeks and rivers could have strong flows, said Ryan Kittell, meteorologist with the weather service, so campers and hikers should avoid them.
Big surf is also expected Sunday through Tuesday.
Atmospheric rivers explained
Made visible by clouds, atmospheric rivers are ribbons of water vapor that extend thousands of miles from the tropics to the western U.S. At 250 to 375 miles wide, they provide the fuel for massive rain and snowstorms that can cause flooding along the West Coast.
In general, atmospheric rivers pick up water vapor from the warm, moist air of tropical regions and then drop the water over land in cooler regions as rain or snow.
On average, up to 50% of the annual precipitation on the West Coast occurs in just a few atmospheric river events.
More: What is an ‘atmospheric river’? These rivers of water vapor can extend thousands of miles.
Contributing: The Ventura County Star; Jeffrey Meehan and Siobhan McAndrew, The Reno Gazette Journal
Source: eu.usatoday.com
