In Oregon, we don't get high heat and high humidity like you are seeing in that forecast. I found a chart on Granger's site that gives me context:
View attachment 5400878
Uck. 97 F, 75% RH feels like 132 F or 56 C. I hope you have a safe place to ride it out. Stay safe.
Back when I had the bike, I saw a peak of 118° on the thermometer I’d mounted on it. This was the Sierra foothills, so humidity 20% tops. Not a problem in my summerweight riding jacket (no way would I throw a leg over my ferrous steed without jacket and helmet).
In ‘03 I had the experience of riding through south-central Texas. It was 98°, but muggy. At some point riding through the flatlands to the left of the middle of nowhere, I started to hallucinate.
A few miles on, there was a roadside diner. I spent an hour in their AC, dumping heat and taking on a rather large amount of soda. The rest of the day went fine, but it was full dark when I trundled into Eagle Pass (recently in the news for anti-immigrant shenanigans.)
West coast heat is nothing like East/Gulf heat.