It's not the heat that holds me back...quite the opposite actually. One year we were there 2nd week of August, and I was wrapped in a towel at Typhoon Lagoon, drinking hot chocolate. One dip in the shark encounter did me in!

I was more along the lines of the crowds and changes....I will need a whole new arsenal of tips before we head back.
rkmassa: We had a mixed bag of crowded days in Dec. We did a split stay WL/DOLPHIN trying to work the location angles. Itwas crowded on the 18, 19 at MK as we expected being the weekend, a ton of people arrived the same weekend as just about every school was out for break by then. Monday we did AK and it was not too bad, but the weather was cold. Tuesday (21) cold, crowded, Wed beautiful day, mid 70's swam at WL and did the resort switch, hit MGM that night, pretty crowded but I think because the weather was so nice. Thurs (23) Did Epcot, doable, but def needed fast pass and PS for eating/jumped over to MGM, again, prettty crowded, most FP were gone for TOT, RRC, INDY JONES, but saw the Osborne lights and just hung out. On Christmas Eve it was rainy and chilly, we bummed around AK and Epcot, had 8:30 PS for O'Hana's...FANTASTIC time, meal, seats, saw a couple get engaged, fireworks from table...and the best part, we decided to try MK around 10:30...what the heck we thought, we're right here, yes it's freezing....but we walked on just about EVERYTHING we had time for! SM, HM, BUZZ, PeterPan, Dumbo,BTMRR, (skipped SM but could've had the ride to ourselves) Philharmagic.we were exhausted from running from ride to ride. All the little ones were at their resorts waiting for Santa, and the cold must have kept others away! Being on MainStreet at midnight when it turned to Christmas was so cool...best moment of the trip. Xmas day we went to Epcot, it was not too bad, again, weather (rainy chilly) held folks off. That was our last maneagable day crowd wise...the 26, 27 were jammed, and we just hung around the Dolphin on the 28 before our evening departure. We loved that the parks were open later, but we really like the daylight hours too and wished it was summer for the longer sun hours. Glad we did it, even MORE glad we had 10 days and had been before so did not feel too much pressure if we missed something. We did have PS for each day, it was a lifesaver, and we had our ponchos, gloves, winter coats so we braved the elements. We even commented that id we were back in Il NO WAY would we be at a theme park in this weather...but WDW is so much more than a theme park. It did wear us out tho, so waiting 'till next summer is o.k. w/us....just can't wait for E. Everest and to try Soarin'!
Pam