San Francisco just had its second-rainiest day since 1849

Re:San Francisco just had its second-rainiest day since 1849 by Ozzie_osman on Sunday January 01, 2023 @03:15PM (#34210376)

I was driving back from San Francisco to the South Bay in the early afternoon. Parts of the 101 were apparently closed off, so we took the 280, and saw several accidents along the way. Visibility was quite poor and the roads were very slippery. Haven't seen it this bad since I moved to the area about a decade ago.

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Re:San Francisco just had its second-rainiest day since 1849 by arcticbull on Sunday January 01, 2023 @03:24PM (#34210469)

To be fair most of that decade has been a state-declared drought (2012-2016) :) and I believe the interceding years were also usually low in terms of precipitation even though they didn't meet the formal definition of a drought.

None of that detracts from this of course.

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Re:San Francisco just had its second-rainiest day since 1849 by cj on Sunday January 01, 2023 @03:46PM (#34210682)

> the roads were very slippery

This is one thing that surprised me when moving from NY (lots of snow) to SF.

Rain in SF seems to trigger traffic conditions similar to light snow or ice in the northeast.

I’ve always been curious what causes this. (My guess is people are slower to replace balding tires when there isn’t frequent rain or snow)

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Re:San Francisco just had its second-rainiest day since 1849 by maxerickson on Sunday January 01, 2023 @03:53PM (#34210758)

One theory is that oils build up on the road surface.

https://blog.response.restoration.noaa.gov/oil-water-and-dan...

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Re:San Francisco just had its second-rainiest day since 1849 by Manuel_D on Sunday January 01, 2023 @04:16PM (#34211001)

Infrequent rain means when it does rain lots of oil floats to the surface and creates poor road conditions. That, and drivers are less accustomed to driving in rain. By comparison, here in Seattle light to moderate rain and people still drive at full speed. A heavy downpour will slow things down a bit.

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Re:San Francisco just had its second-rainiest day since 1849 by Gibbon1 on Sunday January 01, 2023 @06:01PM (#34212025)

Life long Bay Area resident here. This is absolutely the case. When I used to commute over HWY17 I started taking the day off on the first rain of the season because it was way too slippery to be safe. Corners that were safe enough at 55 in the rain normally people would spin out going 35.

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Re:San Francisco just had its second-rainiest day since 1849 by colechristensen on Sunday January 01, 2023 @03:54PM (#34210766)

I’m pretty sure it’s just that people are so inexperienced when it comes to wet roads that the slightest bit of loss of traction causes chaos.

I’m sure buildup of dirt and oil on roads that isn’t regularly washed off with rain makes things a little worse.

But like in Minnesota there are always tons of accidents during the first snow of the year. Then people remember how to drive in the snow and everything is fine for the next 40 snows.

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