Well, Blow Me Down! Why the Hell Has S.F. Been So Windy Lately? We ask a Scientist
Windy day got you down? Well, get used to it.
By Joe Eskenazi
The last few days have been the sort that leave toupee-wearing San Franciscans thanking God (and Sy Sperling) for that money-back guarantee.
High hemlines and higher winds have combined to turn city dwellers into impromptu gynecologists. Less salaciously, your humble narrator has personally witnessed both a walk/don’t walk sign and the F-Line Trolley’s marquee being blown into the street. And, tragically, 50-year-old Kathleen Bolton was killed when a redwood branch landed atop her as she loaded her dog into the car (the dog was unhurt — we know you were wondering).
That San Francisco is a windy place has been a matter of national consensus ever since Stu Miller was supposedly blown clear off Candlestick Park’s mound during the 1961 All-Star Game.
And yet, the last few days have been exceptional — and, as Bolton’s survivors can tell you, the results have been a bit more dire than the balk and unearned run charged to Miller.
What’s up with the bluster? I asked a scientist to explain it — and he did.
Norm Miller is a professor of Geology at U.C. Berkeley and a staff scientist in the climate department of Lawrence Berkeley National Laboratory. And his explanation for San Francisco’s temporary conversion into a wind tunnel is so simple he only had to run it by me three times.
You remember that beautiful weather we had over the weekend, right? Well, apparently it came with a cost.
“On Friday, it was really hot and cooking and there was a big, high-pressure buildup just inland,” he said. Meanwhile, a low-pressure storm system developed north of San Francisco — it was raining in southern Oregon and northern California on Friday, which explains the coolness we feel now. And, just as a watermelon released atop California Avenue will roll toward the Bay, an air mass will run from high to low pressure. In other words, hold on to your hats, San Francisco.
And, Miller notes, be prepared to lose a few hats in the future. Computer models based on probable global warming trends indicate more and more high-pressure systems will build up over the Great Basin in Nevada. When low-pressure systems develop offshore, San Francisco will be converted into the Highway 101 of wind.
“The typical rule of thumb is that you take the temperature difference in Sacramento and San Francisco and you can always calculate the wind speed for sailing in the Bay,” explains Miller.
So, in other words, the fallout from global warming won’t be bad news for everybody. If you have access to a sailboat, good for you. If you have access to tall trees (or, more accurately, they have access to you) — not so good.
Photo | Courtesy of funny.co.uk