Weather Tidbits: Car Windshield Frost

This edition of weather tidbits will be discussing car windshield frost. The car windshield warms and cool diurnally faster than the surrounding air. For frost to form, the temperature must drop to the dewpoint at said surface with temperatures at or below freezing. If this criteria is met at night, the moisture air condenses, cools, and freezes on the cold windshield, much of the time lingering into the morning. Ice is fairly easy to scrape off and melt with the defroster with temperatures between 29-32 degrees, but becomes more difficult with temperatures below that. To get rid of the ice, start the engine and turn the defroster to full heat. Never us a metal scraper, hot water, or a flamed torch. A metal scraper can damage the window and wiper, while the hot water on the frosty windshield could cause it to crack.