We got a great question this morning from Tom in Cape Coral:
I live on SE Cape Coral and there is frost all over my yard and vehicles, but you are still reporting it is 36 degrees. I thought it took a temperature of 32 degrees to freeze?
And Tom is absolutely right, it does take a temperature of 32 degrees for water to freeze. But where that temperature is 32 is key. As you may know, the air temperature can vary significantly over a fairly shallow depth of the atmosphere. On a very cold morning like this, the reported air temperature (usually measured at 6 feet above ground level) might be 36 BUT, close to the ground the temperature is often several degrees lower. In this case, the formation of frost indicates that the temperature of the surfaces on which frost is forming (like blades of grass or a car's wind shield) are below freezing... even though the temperature just a few feet above the ground is a few degrees above freezing.
Great question!
Brian
