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k UNITED STATES
DEPARTMENT OF LOCAL CLIMATOLOGICAL DATA
COMMERCE
PUBLICATION
ANNUAL SUMMARY WITH COMPARATIVE DATA
HUNTSVILLE, ALABAMA
■ I c nCDADTWlCNT Ac r'AWiMEDr'E NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION
1973 U.b. UtP An I Mt lx I Uh UUMIVItKUfc ENVIRONMENTAL DATA SERVICE
NARRATIVE CLIMATOLOGICAL SUMMARY
Huntsville has a temperate climate. Summers are
characterized by warm and humid weather, with
rather frequent thundershowers. Winters are
usually rather cool, but vary considerably from
one year to the next.
The city of Huntsville is almost surrounded by
the foothills of the Appalachian Mountains. The
Tennessee River winds its way westward about
7 miles to the south of the City, and the broad,
fertile Tennessee River Valley, with flat to
gentle rolling terrain, extends to the west. The
weather station is located at the Huntsville-
Madison County Airport, which is 11 miles
southwest from the center of Huntsville. Moun­
tain ridges, with elevations from 1,200 to 1,600
feet above m.s.l., are located some 14 miles
to the northeast, east, andsoutheast of the airport. latively dry weather of fall is an occasional
Cold airmasses from the continent are pre­
dominant over the area during the winter season,
but at times mild air from the Gulf of Mexico
spreads northward to Huntsville or beyond, and
may persist for several days in succession.
The contrast between airmasses frequenting the
region in winter provides a potential source of
energy for producing extensive periods of low
cloudiness and rain, the result being that four
months, December through March, account for
about 43 percent of the normal annual precipita­
tion. Severely cold weather seldom occurs.
Temperatures average dropping as low as the
zero point about once per year, usually under
clear skies with only light winds.
In the transition from winter to spring, appear­
ances of warm/ moist air in place of the cold
air become more frequent, and the greatest
variety of weather usually occurs during this
season. Spring season thunderstorms in the
vicinity of the boundary between warm and cold
airmasses are more likely to be accompanied
by locally severe weather conditions than thunder­
storms in other seasons.
Day to day weather changes in the summer season
are rather small other than the occurrence of
thundershowers that provide relief from the heat
on about one-third of the days. Temperatures fre­
quently rise to 90° or higher, but reach 100° only
on rare occasions.
During the fall the weather is usually dry and
pleasant. The airmasses are cooler in the
lower levels and the thundershower activity
of summer decreases sharply. The dry air is
very favorable for the harvesting of cotton
and hay crops, important items in the economy
of thb area. A major departure from the re­
rainy spell of one or more days associated with
a decadent hurricane drifting northward from the
Gulf of Mexico.
Precipitation amounts for the drier months of the
fall are appreciably less than for the relatively
wet season in winter; however, with the exception
of an infrequent long dry spell, precipitation
distribution is such as to provide adequate
moisture for plant growth throughout the year.
Precipitation is mostly in the form of rain, but
snow can be expected to some extent each winter
and seasonal totals have ranged from less than an
inch to over 20 inches.
In the Huntsville area, the average date for the
last occurrence in spring of temperatures as
low as 32° is March 30, and the average date for
the first occurrence in the fall of temperatures as
low as 32° is October 31, thus giving a growing
season of 214 days. The climate is suitable for
truck farming, as well as for staple crops and
livestock.