IEM Daily Feature
Wednesday, 08 December 2004

Beware of frost

Posted: 08 Dec 2004 08:34 AM


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8 AM pavement temps on 8 Dec 2004
As most Iowans know, road frost is very dangerous to drive on. Basically, frost forms when the below freezing temperature of the pavement surface is less than the dew point of the air immediately above the surface. The IEM produces a number of plots to help diagnose frost including the featured plot which maps the 4 pavement sensor temperature with the sub surface temperature shown in red. During this time of year, the subsurface temperatures are still very warm, so it often helps to warm the pavement surface from below and keep our roads in better driving condition.