20 degree drop in temperatures in last week or so in Northern California

I decided to ride my dualsport 2009 Kawasaki KLR 650 today along the coast. I didn't notice too much that it was in the low 50s but noticed I was chilled when I returned home. So, after Skyping with my son in another state with my wife I got into my hot tub that I had set for 100 degrees. I was really happy when I opened it up and looked at the temperature and it said 101 degrees (Fahrenheit).
So, I'm soaking in the Hot Tub now outside and the air temperature is 54 degrees Fahrenheit Right now even though the temperature today never got above the high 50s.

Last week I think it was I was writing and wondering when the temperatures were going to drop. I think I liked walking around in the sun in Bermuda shorts better than this. because now it is not only in the 40 to 59 range it is also cloudy every day lately as well. But, this is Halloween weather here on the Northern California Coast.