okay 100F equals about 37C, which is hotter then any weather we have had this year (35C was the hottest)
i put my ducks outside, there about 9 weeks out in that weather (right now its like 31C) and there outside, i just give them lots of water (my ducks dislike pools they freak out when ever i try to get them to swim) but i did splash them with water, i got out the old Nerf super soakers and had a water fight with my ducks (they where about 8 weeks old at the time) they then tried to eat the water i was spraying them with and they then enjoyed playing in the mud.
again i might not be much help on this subject, just what i have done.