Istria in November

With this message I would like to ask you few questions regarding weather conditions in Istria during November. My idea is to take few days off and travel by car to Istria for good slalom and wave windsurfing. I have been following windguru.cz and there is nice forecast coming there.

What temperature may I expect and where should I go to find right spots. Will I find there some fellow windsurfers? Traveling by car from Austria / Slovenia - will you reccomend any roads to follow?

Thank you in advance for speedy fedback.
Regards