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\ " \. L I ' I 2.11 Ice/Winter Storm Hazard Identification: Winter storms originate as mid-latitude depressions or cyclonic weather systems, sometimes following the path of the jet stream. A winter storm or blizzard, combines heavy snowfall, high winds, extreme cold and ice storms. Many winter depressions give rise to exceptionally heavy rain and widespread flooding and conditions worsen if the precipitation falls in the form of snow. The winter storm season varies widely, depending on latitude, altitude and proximity to moderating influences. The occurrence of large snowstorms, ice storms and severe blizzards can have a substantial impact on communities, utilities and transportation systems, often resulting in the loss of life due to accidents of hypothermia. Heavily populated areas are at high risk because the severe weather can cause communication and power lines to go down. High levels of snow can accumulate, building faster than it can be cleared and heavy icing can impact utility systems and transportation routes. Damage to buildings often occurs in areas where the normally anticipated snowfall depths are not considered in building codes. Roof collapses damage residential, commercial and industrial structures. I The degree of exposure to severe winter storms depends on the normal severity of the region's winter weather. Nearly the entire United States, with the exception of the extreme southern states, Hawaii and the U.S, territories can be affected by severe winter storms. Alaska, the Upper Midwestern and Northeastern states tend to be more, susceptible than others, but generally these regions are better prepared for severe winter weather. The regions where extreme winter weather is less common tend to experience more damage and disruption when the storms hit. Areas along the Gulf Coast and Southeast regions of the United States are generally unaccustomed to snow, ice, and freezing temperatures. Once in a while, cold air penetrates south across Texas and Florida, into the Gulf of Mexico. Temperatures fall below freezing killing tender vegetation, such as flowering plants and the citrus fruit crop. Wet snow and ice rapidly accumulate on trees with leaves, causing the branches to snap under the load. Motorists are generally unaccustomed to driving on slick roads and traffic accidents increase. Some buildings are poorly insulated or lack heat altogether. Local municipalities may not have available snow removal equipment or treatments, such as sand or salt, for icy roads. While snowstorms are not frequent in Texas, ice storms create dangerous driving conditions, may freeze pipes and down power lines. In January 2001, a severe ice storm caused Hunt County to declare a Presidential Disaster Declaration. A north eastern Texas ice storm ending on January 2, 1979, which had lasted 6 days, was said to be the worst ice storm in Texas in 30 years. An eastern Texas ice storm ending on January 1, 1999 caused power outages lasting more than two days. I The Hays County Mitigation Planning Committee classified Ice and Winter Storm as "limited" in severity and "unlikely" in frequency. Hays County, Texas Miligalion Plan 80