Definitely cooler than the week we spent there in August this year.
We stayed at Portal RV (resort side) and it was definitely off season. Campground about 1/3 full. Nice concrete pads and nice showers and pool. You only get access to pool side if you stay in that area. The other side is gravel pads but still quite good. Lots of long sites.
Www.portalrvresort.com
Search "Moab" in campground recommendations section and you will get more info and reviews.