Not nearly as common as long weekends in Paris, Spain, Italy, etc.

Now extrapolate that to "long weekend in California." and it's again much less common.

I remember at one point seeing ads in Boston for Icelandair that pretty clearly implied you might go to Iceland for a long weekend. It seemed a bit preposterous, but I was in Boston for just a couple days from San Francisco, and Iceland is actually closer to Boston than San Francisco is. And in the summer the Boston - Reykjavik time difference is only four hours.

If you google "long weekend in Iceland" there are articles (https://www.travelandleisure.com/weekend-getaways/long-weeke..., https://inspiralized.com/lifestyle/a-long-weekend-trip-to-ic...) that suggest doing this. It actually sounds not unreasonable if you can manage to power through that first day.