California and Florida both have lots of shoreline, and therefore lots
of fog and low clouds. Plenty of IMC and not as much ice in the lower
altitudes as colder just-as-wet areas, like Michigan.

I live on the coast in northern California. I plan to get an instrument
rating simply for proficiency, but it will come in handy on those days
when the ceiling is 400 feet but you can see sunshine looking straight
up, because the layer is only 100 feet thick. It is particularly
pernicious in the summertime.


One thing I find remarkable is that "sunny" Florida and
California each have a higher percentage of instrument
flyers than "rainy" Oregon and Washington.