Snow continues to challenge
weather experts across the country. It is still very difficult to predict
and is surprisingly hard to measure once it has fallen.
Based on National Weather
Service records for 1961 through 1990, Rochester, New York averages 94 inches
of snow annually and is the snowiest large city in the United States. Rochester
has a population more than 200,000 and annual municipal snow-removal budget
of $3.7 million (1995 figures).
Buffalo, New York, is
a close runner-up in terms of U.S. large cities with the most snow. A 39-inch
snowfall in 24 hours in early December 1995 cost the city nearly $5 million
for snow removal.
Each year an average
of 105 snow-producing storms affect the continental United States. A typical
storm will have a snow-producing lifetime of two to five days and will bring
snow to portions of several states.
In the early 1900s, skiers
created their own terminology to describe types of snow, including the terms
"fluffy snow," "powder snow," and "sticky snow." Later, the terminology expanded
to include descriptive terms such as "champagne powder," "corduroy," and "mashed
potatoes."
Fresh snow is an excellent
insulator. Ten inches of fresh snow with a density of 0.07 inches, seven percent
water, is approximately equal to a six-inch-layer of fiberglass insulation
with an insulation R-value of R-18.
Practically every location
in the United States has seen snowfall. Even most portions of southern Florida
have seen a few snow flurries.
Snow kills hundreds of
people in the United States each year. The primary snow-related deaths are
from traffic accidents, overexertion, and exposure, but deaths from avalanches
have been steadily increasing.
The greatest snowfall
officially reported at the Phoenix, Arizona National Weather Service Office
was one inch. That occurred twice. The first time was January 20, 1933. It
happened again four years later on the same date.
In the western United
States, mountain snow pack contributes up to 75 percent of all year-round
surface water supplies.
The commonly used ten-to-one
ratio of snowfall to water content is a myth for much of the United States.
This ration varies from as low as 100-to-one to as high as about three-to-one
depending on the meteorological conditions associated with the snowfall.
Nationwide, the average
snowfall amount per day when snow falls is about two inches, but in some mountain
areas of the West, an average of seven inches per snow day is observed.