Friday, June 30, 2006

Freezing rain

Freezing rain begins as snow falling from a cloud towards earth. It melts completely on its way down through a layer of warm (above freezing) air and then supercools in a small layer of cold air just before it impacts the surface. Due to it being supercooled the water freezes again upon impact. The ice can accumulate to thicknesses of several centimetres. The METAR code for freezing rain is FZRA.

Ice storms often cause major power outages. Power lines coated with ice become extremely heavy, causing support poles, insulators and lines to break. Tree limbs, with branches heavily coated in ice also can break off under the enormous weight and fall onto power lines. The ice that forms on roadways makes vehicle travel nearly impossible. Unlike snow, wet ice provides almost no traction, and vehicles will slide even on gentle slopes.


Post a Comment

<< Home