If your UTH is on a thermostat you don't need to unplug it. If set up properly it's not putting out heat anyway.
As long as you're not talking 90s or warmer for a stretch of time your snake will be fine.
Putting a water/Gatorade bottle of ice in the enclosure will help if temps get too hot. If you're talking high 80s you've got nothing at all to worry about short term.