Los Angeles Times
And on the 8th day, it was still pretty chilly in L.A.
Los Angeles is on track to experience its longest cold snap in almost 20 years this week as another winter storm blasts the region with more low-elevation snow, strong winds and significant rain.
If forecasts pan out, Wednesday will be the eighth day in a row that downtown L.A. hasn’t topped 60 degrees — a chilly streak not seen in the city since 2005, according to the National Weather Service’s daily forecast discussion.
Los Angeles’ normal average for the month is 69 degrees, making this recent streak well below normal, said Ryan Kittell, a meteorologist with the National Weather Service office in Oxnard.
“It’s been pretty darn cold,” Kittell said.
Though this streak could tie a similar eight-day cold snap in January 2005, it pales in comparison to the longest on record: 20
schalck, chief of the climate center’s operational prediction branch, said in an email.
In the coming days, the western United States is expected to be “dominated by upper-level low pressure,” Gottschalck said, which will probably deliver more low temperatures and low-elevation snow to California. That means “much of the precipitation, at least in the next week, will add to the snowpack.”
But the arrival of more precipitation in the weeks that follow could be some cause for concern.
UCLA climate scientist Daniel Swain said about 20% of forecast models project a very strong and warm atmospheric river storm in California around midMarch. A series of nine atmospheric river storms hammered California in early January, breaching levees and contributing to nearly two dozen deaths.
Should such an event occur in the wake of extensive snow, “that could indeed pose [a] significant flood threat,” Swain said on Twitter. However, he said that is “speculation at this early juncture” because the present odds of such a warm storm are about 1 in 5.
The recent winter storm already dropped heavy cold rain and snow in parts of California. Many Southland peaks received more than 50 inches of fresh powder, with the Mountain High ski resort in Wrightwood recording 93 inches, according to the National Weather Service. Daily rainfall records were set at Los Angeles International Airport and in Burbank, downtown L.A. and other spots.
Across the state, snowpack remains incredibly healthy — 186% of normal for the date as of Tuesday, according to state data. In the southern Sierra, it’s 224% of normal. Reservoirs are notably healthier too, with Lake Shasta nearly doubling its volume from two months ago.
The immediate forecast in the Sierra is continued icy conditions, including “a very cold pattern with multiple feet of snow this weekend,” said Wendell Hohmann, a meteorologist with the weather service in Reno.
“The amospheric river signals are pretty far out there, so predictability is pretty low and confidence is therefore pretty low on that,” Hohmann said, “but it does kind of open the door for us to keep an eye on it at this point, see how it evolves.”
In addition to flooding, a warm rain-on-snow event could pose challenges from a water supply perspective. Earlier-than-usual snowmelt, especially in the Sierra, can make it harder for the state’s water managers to plan ahead, and can have negative effects on hydropower and ecology, experts say.
Sweet, of the weather service, said he primarily focuses on short-term forecasts but has also been keeping an eye on the longerrange models, which are “starting to hint” at the possibility of such a system.
As it stands, the forecast for more precipitation of any kind comes amid a winter that has already defied expectations in California. In October, seasonal outlooks pointed to a drier-than-normal season driven by a rare third appearance of La Niña. The fact that conditions ended up so wet speaks to the challenges of long-term forecasting, Sweet said.
“We still don’t have an absolute razor-sharp focus, or way of looking at the extended forecast, and being really sure of it,” he said.
Despite its hazards, the wet weather has had many upsides in California.
Improved snowpack and reservoir levels have allowed the state’s water managers to tentatively increase State Water Project allocations to 35%. In December, they said they would be able to give only about 5% to 29 agencies, which together serve about 27 million Californians.
The U.S. Drought Monitor also moved nearly all of California out of its worst two categories — exceptional and extreme drought — this year for the first time since 2020.
As of this week, about 33% of the state remains in severe drought, the thirdworst category, according to the Drought Monitor. About 52% of the state is categorized in moderate drought and 15% as “abnormally dry.”
One small county — Del Norte, in the state’s northwest corner — has moved out of drought completely.