![]() We’ve also had 26 Octobers with more than 2 inches. Fourteen of those were completely dry, zero-point-zero. Going back to 1849, San Francisco has had 26 Octobers with 0.05 inches of rain or less. In the long-term record, October rain shutouts aren’t unusual in the Bay Area, according to rainfall records kept by Jan Null of Golden Gate Weather Services. My first-born daughter had just learned to walk in 2013 when, for the first time in my life, it failed to rain any amount in San Francisco in the month of October. But there was a caveat to those years, too: varied meant that sometimes it rained a little, and sometimes it rained a lot. The October rains varied, because that’s Bay Area fall climatology. Very wet again in 1984, with more than 2 inches. It was drier in 1983, around a quarter of an inch. Two-point-eight inches in 1982, a big El Niño year. San Francisco got 2 inches of rain in October 1981. That would turn out to be a very dry October. It rained 0.06 inches in the Bay Area in October 1980, my first experience of October rain. #CAwx #CAfire #CAwater /PHgOZEUWgb- Daniel Swain October 13, 2021 Before we assume it will happen, we can ask: where’s the conflict?Ĭalifornia, on statewide basis, is now experiencing its worst drought in observational record going back to late 1800s–narrowly beating out peak of last drought in 2014-15 (as measured by PDSI, a metric that takes into account both precip & temperature). And so, like the forecaster, we can look at what the weather models show us might happen, and watch them match so closely with what we need and want to have happen. This parched, tinderbox state desperately needs water. Now we’ve reached the middle of the month and there’s rain on the ground and in the forecast. On October 13 California surpassed the driest point of the 2013-2015 drought and was the driest it had been in the 126-year observational record. Two weeks after the forecast showed a chance of rain, a hair-raising north wind started dozens of new fires. October in California is the month when those states conflict the most. There is what weather we want, and what weather is supposed to be, and what weather happens. At the time the various weather prediction models all showed some chance of real rain two weeks out, and the forecaster stuck a caveat on the computers with this phrase: “we’re fighting climatology.” I read the Bay Area AFD with religious devotion three times a day (although I admit I still can’t explain a retrograding shortwave) because sometimes a line leaps out even to the lay reader. This bulletin, called the Area Forecast Discussion, goes into detail about various technical weather things like fronts and trough axes and cold air advection aloft as a consequence of retrograding shortwaves. Every eight hours or so, the forecasters at the National Weather Service office in Monterey write up and publish a summary of what they see happening with the Bay Area’s weather.
0 Comments
Leave a Reply. |