Having passed the RV place on my way out of town yesterday, I can tell you that at 5:30 last night it was 103F or 39C there, and hot it was, too. This is unusually warm for us here in western Oregon.
Before air conditioning, folks here used a fan or more in every room, and sat in front of them with little or nothing on drinking cold drinks of choice. One of my college days cheap tricks (before car air conditioning) was to take along a spray mist bottle and squirt myself down every so often. This works particularly well in a breeze.
One of the variants of a swamp cooler involves setting up sprinklers on the roof to keep the house cool.
Blessings,
Barbara