wow Stevo... that's really high. And you say your snake spends time in that hide!?!?!?
What is the cool side of you viv at?
Is there another hide for your snake to move to on the cool side (when he's over-cooked)?
As I have learned by reading a lot of posts on temps in the last few weeks the hot spot shouldn't be more then 90 degrees, and 80-85 is better. Some snakes like it a bit hotter then others (my hot spot in the day is usually around 92 degrees, but Zea naver spends too much time there).
If you are using an under tank heater then you need to get a rheostat to reduce the temp.
If you are using a light as your source of heat then you need to reduce the wattage.
You can also try poking holes in the top of the hide so the heat can escape (it seems to me like it's being trapped in there).
Be careful with high temps and your snake. Read some posts about high and low temps and the effects on your snake. And, if you don't have the Corn Snake Manual by Bill and Kathy Love, get it!
Hope you snake cools-off.............