Well, this is a forum on the internet…. I’m not publishing a paper for peer review…. But I’ve produced evidence below if that makes everyone happy.Having lived in 2 decades in a western state with a lot of rain, I've never seen any kind of road signs like you say.
I'd like to see any links to "experts" saying "you are *never* supposed to use any type of cruise control, TACC, auto pilot or FSD in rainy or snowy weather on any car". If not, it is just your opinion - which is fine. But when you start saying thats what "experts" say, you have to produce evidence.
That being said….
I don’t know where you live but…. Interstates in Colorado often flash signs when snow and rain are happening to take your car out of cruise control. When I lived in Fort Collins these were prevalent in winter on I25 and I70. You will also see this on Interstate 80 in WY where I lived for 8 years prior to FOCO and then SFNM. I believe I’ve seen this in KS, NE and SD as well but wont swear to that. My highlander and tundra both say very clearly in the owners manual not to use crsuse control in rain and snow conditions. I can take a picture of the tundra OM if you like. I traded the highlander on the MY so you won’t get that one... Both of these vehicles can and do accelerate very hard in corners and on hills when cruise in engaged… Even the smart cruise control has this characteristic in Toyotas and in my previous Audi and Lexus vehicles. It’s just not safe and you should not do it.
A quick google search finds advice from AAA. On the topic. I’d classify them as expert.
or Allstate insurance also probably has some expertise in this space and experience in what happens if you don’t use common sense.
or, or, or…. You can find more if you like with an easy search. More importantly I’d say you can’t find anything from a reputable source saying it’s okay to use cruise in inclement weather. It’s also common sense and something my father thought me when I was learning to drive in WI. I’d classify him as an expert being a fireman and EMT for 30 years driving large fire truck and ambulances. Besides, if dad said it, it’s true…. That last sentence was supposed to be funny just so we’re clear.
Like I said, you can agree or disagree but the fact is that it’s dangerous. Experts do say so. I don’t want to argue or have a pissing contest about this so everyone, please, do as you like and disregard sound advice from experts. That works so well in so many other aspects in our society today, why not keep it up!
Have a great day…