Get a big jacket an bypass the heater core!I treated the interior glass with anti-fog stuff to try and keep the windows clear, but it's depositing a lot of coolant on the windshield - and it's blowing hot air even if the heater is turned off. Interior of the windshield was difficult to see out of with all the moisture on it.
Edit: I know I'm a SoCal weenie but I've had the top off and been snowed on in the Jeep more than once.