Although it doesn't seem to be much of a problem with our cars, you should check and make sure that the A/C drain is not plugged.
The common practice is to probe the drain gently with coat hanger wire from under the car. It is kind of hard to locate since there is heatshield material sort of in the way. On mine it drops right onto the exhaust near the front of the main cat.
Also if you have a strong sweet odor along with it, you may have a heater core leaking. The odor should be obvious. If it is leaking enough to mess up the windshield the odor would be unmistakable.
Or maybe your just breathing too hard when you drive . . . or when your not driving.
