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<br />Damaging thunderstorm winds can produce life-threatening elements of severe storms. In 1995
<br />approximately 38 people were killed nationally and another 473 injured because of destructive
<br />winds. During a period between January 1, 1990 and February 28, 2002, 28 thunderstorms and
<br />high wind events were reported in Hays County, resulting in $6 million in damages and no
<br />deaths or injuries.
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<br />Normally the straight-line thunderstorm winds flowing out from a storm's downdraft do not
<br />exceed about 30 miles per hour. However, when such outflow winds reach 58 MPH (SO knots)
<br />or higher the thunderstorm is then classified as severe.
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<br />Damaging thunderstorm winds have been termed down bursts by renowned severe storm
<br />researcher Dr. Ted Fujita, and he further classifies these events as macrobursts when the
<br />damage area is larger than 2.5 miles, or microbursts when the damage area is less then 2.5
<br />miles. Downbursts can cause damage equivalent to a 'strong' tornado and are extremely
<br />dangerous to aviation, especially aircraft taking off or landing.
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<br />Many windstorm survivors often find consolation in saying they were in a tornado, when in
<br />fact downburst winds were in effect. Downbursts are characterized by divergent, broad, and
<br />diffuse damage tracks, and a lack of rotation about a vertical axis. Aerial surveys after the fact
<br />best reveal these facts.
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<br />The Waco, Texas Tornado, May 11, 1993, is ranked one of the deadliest tornados to occur in
<br />the United States, with a death toll of 114. For comparison, the City of Waco, Texas is only
<br />100 miles north of Hays County.
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<br />Hazard Identification:
<br />Drought can be defined as a water shortage caused by the natural reduction in the amount of
<br />precipitation which occurs over an extended period of time, usually a season or more in length.
<br />It can be aggravated by other factors such as high temperatures, high winds, and low relative
<br />humidity. The severity of drought can depend on the duration, intensity, geographic extent, and
<br />the regional water supply demands made by human activities and vegetation.
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<br />During severe droughts, agricultural crops do not mature, wildlife and livestock are
<br />undernourished, land values decline, and unemployment increases. Droughts can cause a
<br />shortage of water for human and industrial consumption, hydroelectric power, recreation, and
<br />navigation. Water quality may decline and the number and severity of wildfires may increase.
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<br />Droughts can be grouped as meteorologic, hydrologic, agricultural, and socioeconomic
<br />and are summarized below:
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<br />Meteorologic drought is defined solely on the degree of dryness, expressed as a departure of
<br />actual precipitation from an expected average or normal amount based on monthly, seasonal,
<br />or annual time scales.
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<br />Hays counl~', Texas
<br />Mitigation Plan
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