Like Chase said, mig or arc are much worse, then you have to wear tons of leather and gear, where TIG you wear tennis shoes and a t shirt, and just worry about a sunburn.
This last summer, one of our weld stations is next to a west facing steel door, it got to be 140 degrees radiating off of that door in the afternoon.
We went to Lowes and got a patio mister kit and rigged it up outside and above the door to wet the door and evaporate. It lowered the door temp from 140 degrees to 60, and made the area bearable to work in.
I tried one of those big swamp coolers, and it just made my shop humid and hot. What are the tricks to making one of those big swamp coolers work good?