An atmospheric river is moving to the West Coast, likely to bring menacing flooding, heavy mountain snow, and damaging winds.
Atmospheric rivers are narrow corridors of the upper atmosphere that transport intense moisture from a large body of water onto land.
Several storms have barreled across much of California since before Thanksgiving. But now, a shift in the weather pattern looks to bring calmer weather.
Storm after storm dove across the state over the past several weeks, delivering rain, wind and mountain snow.
The jet stream, which helps to influence the track storm systems take, was a big part of the reason for the recent storminess.
Hurricane-force winds, blizzard conditions, heavy snowfall — and a “bomb cyclone” on the West Coast: Those are the dire predictions of weather forecasters, who are warning Thanksgiving travelers to be cautious and prepare for delays as two powerful back-to-back storms hit the western and central U.S. this week.
The National Weather Service’s U.S. forecast map is draped in alarming shades of pink, purple and red, reflecting winter storm warnings that are in effect from California to Michigan.
So far, October and November 2019 has been the driest (or almost the driest) beginning of any recorded water year with almost zero precipitation. (The 2020 water year began October 1, 2019 – so you might have missed a New Year’s party already.)
Should we worry about a drought yet?
Parts of Southern California were under a flash flood watch Wednesday as areas of the southwest saw the first significant rainfall of a delayed wet season that fueled wildfires and forced intermittent power cutoffs to millions of residents.
The storm system brought heavy rain to portions of Arizona, and Phoenix could get 2 inches of rain before the storm ends there on Thursday. Prior to this storm, Sky Harbor International Airport had recorded only 3.68 inches for the entire year.
Coming off a summer of moderate drought with some crop losses, the five Cascade Mountain reservoirs serving irrigators in the Yakima Basin have less water than normal and the winter snowpack outlook is uncertain.
“We are in an El Nino neutral which would mean normal conditions and we would be fairly optimistic. No one has been calling for a dry or mild winter so we have no cause to think it will be,” said Chris Lynch, hydrologist for the U.S. Bureau of Reclamation in Yakima. However, he added, a warm water body off the Gulf of Alaska, reminiscent of one there prior to the drought of 2015, could result in more moderate temperatures and less snow.
After a lackluster amount of rainfall throughout the San Joaquin Valley in 2018, the recent end to the 2019 precipitation year was a welcome sight for community members wary of drought thanks to plenty of storms that brought above-average numbers.
This past precipitation year, which began Sept. 1, 2018 and ended Aug. 31, 2019, saw 45.65 inches of rainfall — nearly 10 inches more than the historical average for the area or about 125 percent of average for the date.
One week after summer’s end, a “winter” storm began blasting parts of the West with up to 3 feet of snow, smashing records with low temperatures, heavy snow, strong winds and blizzard conditions forecast into Monday.
Snow was piling up across parts of California, Oregon, Washington, Montana, Idaho, Nevada and Utah. The National Weather Service, calling the storm “historic,” said temperatures in some areas would drop as much as 30 degrees below normal.
Dust off your windshield wipers, L.A. The first rain of the season dripped from the skies Thursday morning, sprinkling morning commuters.
Extreme fire warnings across California have officially expired, thanks to a slight chance of light rain through Saturday, with low clouds and much cooler temperatures than in the last few days, said Tom Fisher, a meteorologist with the National Weather Service in Oxnard.
