A winter weather event in which rain falls through a shallow layer of sub-freezing air near the surface and freezes on contact with roads, trees and power lines, coating them in a heavy, often destructive layer of clear ice. Even a modest ice accumulation can snap power lines and tree limbs under the added weight, and severe ice storms have left millions without electricity for days, as during the 1998 North American ice storm.
Facts
PeriodicityA winter phenomenon; in the United States most ice storms occur in the northeastern states, though damaging storms have reached much farther south, such as the February 1994 storm that brought heavy ice accumulation to Mississippi and damaged nine states. 1 ScaleThe U.S. National Weather Service classifies a storm as an ice storm once ice accretion reaches at least 0.25 inch (6.4 millimeters) on exposed surfaces. 1 Open Questions
First DescribedNo single first scientific description found in the source consulted.
No source found naming who first scientifically described or classified ice storms; the Wikipedia article gives the U.S. National Weather Service's modern 0.25 inch threshold and the notable February 1994 storm but no historical first description, checked this pass. Identification
Distinguishing AppearanceFreezing rain coats every exposed surface with a heavy, smooth glaze of ice, weighing down branches, power lines and utility poles until they break. 1 Connections
Demonstrated By
Source National Oceanic and Atmospheric Administration
Sources
1. Ice Storm (Wikipedia)
WikipediaFormation section (geography sentence)
In the United States, most ice storms occur in the northeastern region, but damaging storms have occurred farther south; an ice storm in February 1994 resulted in tremendous ice accumulation as far south as Mississippi, and caused reported damage in nine states.
lead section (threshold sentence)
The U.S. National Weather Service defines an ice storm as a storm which results in the accumulation of at least 0.25-inch (6.4 mm) of ice on exposed surfaces.
Effect section (glaze sentence)
The freezing rain from an ice storm covers everything with heavy, smooth glaze ice.
View the Source National Oceanic and Atmospheric Administration
National Oceanic and Atmospheric AdministrationDemonstrated By: Temperate ForestView the Source Reader Challenges (0)
No disputes yet. Spotted an error or a better source? Open the first one.
Sign in to dispute this or suggest a correction.