Laserfiche WebLink
2025 Hazard Mitigation Plan <br />Kittitas County, Washington <br /> <br /> <br />Chapter 4: Hazard Identification and Risk Assessment 153 <br />Strong winds not associated with thunderstorms are often referred to as gradient winds and are usually <br />a result of tight pressure gradients between strong areas of low pressure and high pressure. These strong <br />winds can be just as strong as thunderstorm wind gusts, but cover a much larger area, and can result in <br />widespread damage.191F <br />191 <br /> <br />In coastal regions a strong wind is called a gale. Gale winds are sustained surface winds between 34 <br />and 47 knots (39 to 54 mph). <br />Extreme Temperatures <br />Heat Wave/Excessive Heat <br />The definition of a heat wave varies based on different factors, such as location, weather conditions (e.g., <br />temperature, humidity, cloud cover) and the time of year.192F <br />192 However, excessive/extreme heat can be <br />defined as a prolonged period of excessively hot weather, with temperatures above the average high.193F <br />193 <br />Heat alone does not make high temperatures a threat; both humidity and heat combined is what makes <br />high temperatures a dangerous.194F <br />194 The Heat Index is a measure of how hot it really feels when relative <br />humidity is factored in with the actual air temperature (i.e., ambient temperature). <br /> <br />Figure 4-17 illustrates NWS’s Heat Index Chart. The NWS primarily uses Heat Index values to determine <br />excessive heat events and issue the appropriate advisories.195F <br />195 <br /> <br /> <br />191 National Weather Service. (n.d.). Non Thunderstorm Wind Hazards. Retrieved from <br />https://www.weather.gov/mhx/NonThunderstormWindHazards. <br />192 U.S. Environmental Protection Agency and the Centers for Disease Control and Prevention. (2016). Climate <br />Change and Extreme Heat: What You Can Do to Prepared. Retrieved from <br />https://www.epa.gov/sites/default/files/2016-10/documents/extreme-heat-guidebook.pdf. <br />193 Federal Emergency Management Agency. (n.d.). Extreme Heat | What. Retrieved from <br />https://community.fema.gov/ProtectiveActions/s/article/Extreme-Heat-What. <br />194 National Oceanic and Atmospheric Administration. (2022). Heat Index. Retrieve from <br />https://www.noaa.gov/jetstream/global/heat-index#. <br />195 National Weather Service. (n.d.). Heat Forecast Tools. Retrieved from https://www.weather.gov/safety/heat- <br />index.