Very high humidity levels are normal locally, and have caused problems for several of our club members who had 2 - 6 month interruptions in there flying. In all cases they had not ensured their fuel jugs were completely sealed.... so, they had moisture get into fuel jugs. The symptoms you describe match what they experienced. Check your fuel to see if it is cleanly transparent, or if it seems cloudy or murky (which indicates water has been absorbed into the fuel).