California, and Southern California in particular, is bone dry.
The calendar says spring officially begins with the equinox March 20, but the meteorological winter — consisting of December, January and February — is already in the record books. In other words, the wettest months are over. Let’s take a look at where the Golden State stands.
How dry?
Downtown Los Angeles received 1.84 inches of rain in December, when it normally would get 2.33 inches. Some 2.44 inches of rain fell in January, when L.A. normally expects 3.12 inches. And just a trace (that is, not enough to be measured) fell in February, when 3.80 inches normally falls. January and February are normally the two wettest months in L.A., after which the chances for rain diminish rapidly with the approach of spring and the end of the rainy season.
Disappointing rainfall in downtown Los Angeles reflected a dry winter in Southern California.
(Paul Duginski / Los Angeles Times)
Just 4.55 inches of rain fell over Los Angeles as of Thursday, when it normally should have received 11.68 inches to date.
It’s not just Southern California
Los Angeles and Southern California have lots of company in this respect. The state and the West are gripped by persistent drought, including large areas of exceptional drought in the Southwest, where the 2020 monsoon was a no-show, as the most recent U.S. Drought Monitor report shows. Many water agencies are discussing water conservation measures, and the North Marin Water District is considering voluntary and mandatory water conservation orders.
California’s rainfall picture looks bleak as the meteorological winter — the state’s wettest months — comes to a close.
(Paul Duginski / Los Angeles Times)
Talk of conservation is likely to spread if the drought persists, as is expected, according to the outlook below.
Persistent drought will continue in the West.
(Paul Duginski / Los Angeles Times)
Why is this happening?
California has been plagued by an unusual and persistent upper-level ridge of high pressure in the Pacific off the West Coast. This has been blocking the storm track since last fall, making for a dry pattern that favors Santa Ana winds.
The predominant weather pattern since Oct. 1 has favored dry weather with more Santa Ana winds in Southern California.
(Paul Duginski / Los Angeles Times)
This pattern is consistent with La Niña, which is still in effect in the equatorial Pacific. La Niña occurs when the sea surface temperatures in the central and eastern equatorial Pacific are below average. Easterly winds over that region strengthen, and rainfall usually decreases over the central and eastern tropical Pacific and increases over the western Pacific, Indonesia and the Philippines. This pattern favors warmer, drier conditions across the Southern tier of the U.S. and cooler, wetter conditions in the northern U.S.
La Niña continues in the equatorial Pacific, indicated here by the blue area of cooler sea surface temperatures.
(NASA Jet Propulsion Laboratory and Los Angeles Times)
In the big picture, the drought in the West can be seen as a long-term event, interspersed with a few wet years, that has continued over the last two decades. The longer it lasts, the worse it gets, as climatologist Bill Patzert points out. It affects groundwater and the wildfire situation, and the impacts build over time. The longer it goes, the more push there is for conservation.
Except for a few wet years, the West has been suffering drought for the last two decades.
(Paul Duginski / Los Angeles Times)
The chart above shows not only that the drought is stubborn, but the dramatic rise in extreme and exceptional drought after 2020, compared with the extremes in other years since 2000, is notable.
What are the chances of a March Miracle?
The outlook for March isn’t overly encouraging. Cooler-than-average temperatures are favored in California, and the Southwest either looks drier than average, or has equal chances of being wetter or drier than average. In other words, no March Miracle appears to be in the offing.
The temperature and precipitation outlooks for March.
(Paul Duginski / Los Angeles Times)
“Now that the Ides of March are approaching, the snow and rain drama is whether California will have March misery or a miracle,” Patzert said.
Last-minute relief in March and April 2020 brought Southern California up to about normal, but record-breaking heat in the summer and fall intensified the existing widespread drought throughout the West.
Given that the seasonal average for downtown Los Angeles is 14.93 inches, “there is only one March in the historical record that would put downtown L.A. above average. That was the super El Niño year of 1884, the wettest March and rain year in our history,” Patzert said. “That El Niño delivered colossal March rains of 12.36 inches. In the present modest-to-strong La Niña year, that would be the longest of shots. Think of shooting a basket from the Forum to Staples Center.”
The Link LonkMarch 06, 2021 at 07:24AM
https://www.latimes.com/california/story/2021-03-05/california-is-bone-dry-will-march-bring-more-misery-or-a-miracle
Will March rain help California winter drought conditions? - Los Angeles Times
https://news.google.com/search?q=dry&hl=en-US&gl=US&ceid=US:en
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