California Closes in on Driest Calendar Year on Record
In mid-October, and again mid-November, I posted blogs concerning how dry the year had been in California, ending each blog with the optimistic caveat that the wet season was just beginning and there was plenty of time to catch up precipitation-wise before the end of the year. Well, it turns out that was nothing more than optimism. With only 10 days left and the latest forecast models indicating a close to zero chance for any further significant precipitation to fall in the state, it now appears virtually certain to become California’s driest calendar year on record. Needless to say, California is one of the most water hungry places on earth.
As if to add insult to injury a very unusual late-season wildfire broke out in the Big Sur area along California’s central coast on Tuesday December 17th. The fire burned just 1000 acres but 34 homes were lost. This would appear to be the most destructive December wildfire in central or northern California history and the worst fire in all of California this past year (2013) so far as homes lost. Red flag warnings have never previously been issued for this region during the month of December.An aerial view of the Big Sur fire last Wednesday.
Still from video by KRON/NBC News, San Francisco.
Below is a chart of how much rain has fallen at some select California locations since January 1st (as of December 20th). The annual normal and percentage of such so far this year are in the other two columns:
With no more rain forecast for at least the southern two-thirds of the state until the end of the year, it appears that both San Francisco and Los Angeles will end up experiencing their driest calendar years on record. The previous record for San Francisco downtown was 9.00” in 1917 (POR back to Nov. 1849) and for Los Angeles downtown 4.08” in 1953 (with a POR back to 1877). It is simply astounding by how large a margin San Francisco will beat its previous record (a margin of about 40%!) and this for a period of record going back over 160 years, one of the oldest continuous records for precipitation in the U.S.
Many other locations around the state are also likely to record their driest year. Below is a summary of sites in the southern California area and where they stand vis-à-vis record territory:Since the table was created on December 15th some additional rainfall has fallen at a few of the sites listed including downtown Los Angels with .11”, Burbank with .18”, and Santa Maria with .03”. Notice how Paso Robles (which received no measurable rainfall since December 15th) is on track to beat its former driest year on record by more than 50% and may end up even drier than Death Valley this year (see charts above)!
Table produced by NWS-Los Angeles.
It is not just California that has been so dry but also much of the Pacific Northwest. Eugene, Oregon has received only 21.08” of precipitation so far this year (as of December 20th) against a normal of 46.10”. Its driest year on record was 1944 when 23.26” was measured (POR to 1891). Snowfall is also running well below average as the map below indicates:A map of the percentage of average water content of the snow pack as of December 15th across the western U.S.
I will have a comprehensive round up of the annual precipitation totals and records after the New Year.
Christopher C. Burt