From the Weather Center
by John Simon
According to the National Weather Service in Blacksburg, VA, freezing rain occurs when “the layer of freezing air is so thin that the raindrops do not have enough time to freeze before reaching the ground.”
Instead, the water freezes on contact with the surface, creating a coating of ice on whatever the raindrops contact. Freezing rain is dangerous because the ice can create slick spots on roadways, causing motorists to lose control of their automobiles with little to no warning. Also, ice on tree branches and power lines can cause them to snap or break.
The National Oceanic and Atmospheric Administration (NOAA) says that freezing rain is “most commonly found in a narrow band on the cold side of a warm front, where surface temperatures are at or just below freezing.”
The accompanying diagram shows a typical temperature profile for freezing rain.
In the United States, most ice storms are in the northeastern part of the country, but damaging storms have occurred farther south. An ice storm in February of 1994 resulted in tremendous ice accumulations as far south as Mississippi, and caused reported damage in nine states.
The worst ice storm on record occurred on December 4 and 5 in 1964.
Freezing rain caused ice accumulations of up to 1.5 inches and crippled east central New York. Many residents were without power for up to two weeks, and schools had to be shut down for a week.