Karl the fog San Fransisco

[Anyislandwilldo]

I've read that Karl the fog can roll in around 3 in the afternoon so be prepared.  Can you tell how the fog is?  Is it thick like pea soup or visibility of a mile or so. I suppose the temp will drop rapidly as well.   Thanks.

Edited December 17, 2022 by Anyislandwilldo

[CruiserBruce]

The fog will be above your head most of the time, not pea soup. Yes, the temps will drop into the 50s. 

 

Of course, you didn't tell us when you will be in SF. Fog isn't a year around, or every day thing...for example, today (and for the last couple of days, and most likely the next few), it was crystal clear in SF. Spring and Fall are typically the least amount of fog.

[ATSEAMYLIFE]

Fog in San Francisco is a crap shoot.  We have sat at the bar atop the Hilton Financial District (highest hotel bar in San Francisco) and watched it go from clear to you can't see anything within 20 minutes and then do that three more times before the sun goes down.  It's not so much the air temperature drops as the radiant heat from the sun disappears and the fog is wet so you get chilled.   Fog is inversely related to the temperature and dew point between the SF coast and the inland valley.  While it might have been crystal clear today in SF, as CruiserBruce points out, less than 30 miles to the east in the central valley it was 100 yard visibility.  If the dew point and temperatures flip then the valley will be clear and SF fogged in.  That being said, San Francisco even on a cold, but clear sunny day is spectacular.  Watching "Karl" dance across the City is part of the charm.