Do you have a basement?
Where are you keeping the snake?
A heatwave where I live doesn't really pose any immediate danger to the snakes because they are in the basement. We do have AC but sometimes I like a 95 degree, humid day so I let the place warm up. Unless my wife objects and then I turn on the AC.
If you don't have a basement to move the snake into, I would make sure there is no direct sunlight on the cage. Take regular readings of the in cage temps and adjust as needed.
Most snakes live in climates that are very hot and very moist. They regulate their body temps by moving into warm areas and then into cooler areas however, cooler is relative and doesn't mean "cold". South American jungles and African plains or Malaysian jungles are not typically cool but they are moist.
IF your snake is feeling overly hot it will likely find a water bowl and submerge to cool down.
I suspect you already have a big bowl or you can easily provide one?
Change the water frequently if your snake spends any significant amount of time in it.
Misting the cage with cool water can drop the cage temps a bit.
I don't know enough about your setup or the other options you have in the home. Because of that I can't offer much more advice.
If you have shade and don't expect cage temps to go much above the mid 90's, I don't think you have much to worry about.
A big, cool water bowl should solve you problems.