Geoscience Reference
In-Depth Information
Snow Squalls—Brief, intense snow showers accompanied by strong winds.
Accumulation could be significant.
Snow Showers—Snow falling at various rates for brief periods of time. Some
accumulation is possible.
Ice Jams—Long cold spells can cause freezing of lakes, rivers, and creeks. A
rise in water level or a thaw can lead to the breaking up of the ice into chunks,
which can act as dams when lodged up against man-made structures such as
weirs or bridge pilings. This can lead to significant flooding.
Snow Melt—The sudden thawing of a heavy snow pack that often leads to
flooding.
Wind Chill—How wind and cold temperatures feel on exposed skin. As the
wind increases, heat is carried away from the body at a faster rate, causing the
body temperature to drop.
Historical winter storms include what's become known as the “Storm of the
Century” on March 15, 1993. The death toll from this winter storm is approxi-
mately 270, with 48 people lost at sea. Because of the widespread nature of this
storm, the estimations of damages and casualties were difficult. Thousands of peo-
ple were left isolated by record snowfalls, especially in the Georgia, North Carolina,
and Virginia mountains. In general, all interstates from Atlanta northward had to
be closed. Hundreds of roofs collapsed because of the weight of the wet snow. More
than three million people were without power at one time. At least 18 homes on
Long Island fell into the sea due to pounding surf eroding away the shore. Florida
was struck by at least 15 tornadoes, and 44 deaths were attributed to the tornadoes
and other severe weather. About 110 miles south of Cape Sable Island, Nova Scotia,
a 177-meter ship sank in heavy seas, with all 33 of its crew lost at sea. Sixty-five-foot
waves were reported in the area. The highest winds recorded for this storm included
a 144 miles per hour reading at Mount Washington, New Hampshire, and 109
miles per hour in the Dry Tortugas. Snowfall accumulations included 56 inches
on Mount LeConte, Tennessee, and 50 inches on Mount Mitchell, North Carolina
(with 14-foot drifts). Some damage and cost estimates for this storm exceed $6
billion.
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Consequences of Winter Storms
As discussed in the preceding subsection, winter storms can have a myriad of effects
on an area. These effects include flooding, storm surge, blocked roads, damaged
homes and businesses (from roof collapses), blocked roads, homes isolated from
assistance, power outages, agricultural losses, debris issues (primarily from downed
trees and limbs), damaged infrastructure, structural fires, transportation accidents,
and mass casualties due to exposure to the cold and carbon monoxide poisoning
(Figure 5.7).
