Of all the things that arrive in Los Angeles and spread across America, rain has very rarely made the list. But since Christmas, it has been southern California's most conspicuous gift.
This weekend and beyond, the weather report is a familiar one for many areas of the country: unseasonably warm in the Southeast, the threat of more cold, snow, and slop from the Great Plains to the Northeast, and rain in the so-called Golden State.
None of the weather patterns is all that rare. But their confluence and persistence have made for peculiar weather since the holiday season began, with snow in Texas, early blizzards in Indiana, and monsoons in San Diego. Moreover, with each weather system locked into place, there appears to be more of the same on the way.
"Everything is a little exaggerated," says Robert Kelly of the National Weather Service's Hydrometeorological Prediction Center in Camp Springs, Md. "All [the systems] are unusual in their own right, so to have all three at the same time is more unusual."
The three weather systems emerged just after Christmas and have hardly budged since, held in place by consistent conditions in the upper atmosphere.
Warm, wet air from the Gulf of Mexico is pushing north, bringing springtime temperatures to Dixie. A cold air mass has pushed down over the northern US from Canada, keeping the region susceptible to cold snaps. And winter storms continue to form in the Pacific, then ride the jet stream over southern California to the rest of the country.
During the Christmas weekend, the conditions brought snow to Brownsville, Texas, for the first time since the 1880s. This week, they've brought the wintry mix that hit the upper Midwest and Northeast. Both events were the remnants of southern California storms - and more are coming this weekend.
For the past few years the storm pattern "was that everything appeared to be in the East," says Paul Kocin, a winter-weather expert at the Weather Channel in Atlanta. "This year, it has flipped.... Southern California is getting blast after blast of these Pacific storms, and it normally doesn't get them for years at a time."
Indeed, for all the power outages and school closings across the rest of the country, southern California is catching the brunt of this season's winter weather - and it is not accustomed to such conditions.
Polluted runoff water led to beach closings, authorities shut down one of the region's main highways for 35 hours when two feet of snow fell in the mountains north of Los Angeles, and police in San Diego have reported more than five times the normal number of car accidents.
John Forsythe of the San Diego Harbor Police recalls an SUV stuck in four-foot floods on one downtown street recently. "It looked like a hurricane, like one of those scenes from the East Coast," he says. "In 17 years, I've never seen such crazy weather."
For their part, meteorologists compare this storm season to the winter of 1997-98, when El Niño was at its strongest, causing mudslides across southern California. This year, El Niño doesn't seem to be much of a factor, which puzzles scientists. Yet the signature of a big storm season is apparent.
"The whys of these shifts [of storm patterns from East to West] are not very well known," says Mr. Kocin. "But the tendency in shifts like this is to get storm after storm."