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2025 Hazard Mitigation Plan <br />Kittitas County, Washington <br /> <br /> <br />Chapter 4: Hazard Identification and Risk Assessment 160 <br />Force Wind <br />(knots) Classification Appearance of Wind Effects <br />On the Water On Land <br />12 > 63 Hurricane <br />Air filled with foam, waves over 45 <br />feet, sea completely white with <br />driving spray, and visibility greatly <br />reduced. <br />See Saffir-Simpson Hurricane <br />Wind Scale. <br /> <br />Tornado rating, based on the Enhance Fujita Scale (EF Scale), is assigned after tornado-related damage <br />is surveyed. The EF Scale is based on the estimated wind speeds and related damage. Table 4-99 <br />outlines the EF Scale. When tornado damages are surveyed, they are compared to a list of Damage <br />Indicators and Degrees of Damage which help to better estimate the range of wind speeds the tornado <br />likely produced. The EF Scale was revised from the original Fujita Scale and became operational in <br />February 2007.202F <br />202 <br />Table 4-99. Enhanced Fujita Scale <br />EF Rating 3 Second Gust <br />(mph) <br />0 65 – 85 <br />1 86 – 110 <br />2 111 – 135 <br />3 136 – 165 <br />4 166 – 200 <br />5 Over 200 <br /> <br />The NWS HeatRisk Tool Prototype is a color numeric-based index that provides a forecast of the potential <br />level of risk for heat-related impacts to occur in a 24-hour period. This serves as a supplementary tool for <br />official NWS heat products and is meant to provide risk guidance for decision-makers and heat-vulnerable <br />populations who require certain actions at levels that may be below the NWS heat product thresholds. <br />Table 4-100 outlines the NWS HeatRisk categories and risk of heat-related impacts.203F <br />203 <br />Table 4-100. NWS HeatRisk Categories <br />Category Risk of Heat-Related Impacts <br />0 Green Little to no risk from expected heat. <br />1 Yellow Minor: This level of heat affects primarily those individuals extremely sensitive to heat, <br />especially when outdoors without effective cooling and/or adequate hydration. <br />2 Orange <br />Moderate: This level of heat affects most individuals sensitive to heat, especially those <br />without effective cooling and/or adequate hydration. Impacts possible in some health <br />systems and in heat-sensitive industries. <br />3 Red <br />Major: This level of heat affects anyone without effective cooling and/or adequate <br />hydration. Impacts likely in some health systems, heat-sensitive industries, and <br />infrastructure. <br /> <br />202 National Weather Service. (n.d.). The Enhance Fujita Scale (EF Scale). Retrieved from <br />https://www.weather.gov/oun/efscale. <br />203 National Weather Service. (n.d.). NWS HeatRisk Prototype. Retrieved from <br />https://www.wrh.noaa.gov/wrh/heatrisk/.