Laserfiche WebLink
2025 Hazard Mitigation Plan <br />Kittitas County, Washington <br /> <br /> <br />Chapter 4: Hazard Identification and Risk Assessment 201 <br />4.6.10.4. Probability and Frequency <br />The probability of occurrence for winter weather in Kittitas County is high because significant occurrences <br />of this hazard occur annually throughout the County. The planning area can expect to experience <br />exposure to some type of winter weather event at least annually. <br /> <br />The winter weather annualized frequency value represents the average number of recorded winter <br />weather hazard occurrences, in event days, per year over the period of record (16.9 years). Table 4-154 <br />outlines the annualized frequency for winter weather, based on FEMA NRI data, for Kittitas County. <br />Table 4-154. Winter Weather Annualized Frequency (FEMA National Risk Index) <br />Location Events on Record <br />(2005 – 2021) Annualized Frequency <br />Kittitas County 124 7.7 events per year <br />Annualized frequency is defined as the expected frequency or probability of a hazard occurrence per year. <br /> <br />The ice storm annualized frequency value represents the average number of recorded ice storm hazard <br />occurrences, in event days, per year over the period of record (67.1 years). Table 4-155 outlines the <br />annualized frequency for ice storms, based on FEMA NRI data, for Kittitas County. <br />Table 4-155. Ice Storm Annualized Frequency (FEMA National Risk Index) <br />Location Events on Record <br />(1946– 2014) Annualized Frequency <br />Kittitas County 13 0.2 events per year <br />Annualized frequency is defined as the expected frequency or probability of a hazard occurrence per year. <br />4.6.10.5. Past Events <br />NCEI has reported five (5) ice storm events, 88 heavy snowfall events, one (1) blizzards events, eight (8) <br />winter storm events, and six (6) winter weather events between 1950 and 2023. There have not been <br />any notable winter weather events in Kittitas County. <br /> <br />Table 4-156 lists the ice storm events that have been recorded in Kittitas County between 1950 and <br />2023. <br />Table 4-156. Ice Storm Events (1950 – 2023) <br />Location <br />County / <br />Zone State Date Time Type Death Injury <br />Property <br />Damage <br />Crop <br />Damage <br />KITTITAS VALLEY <br />(ZONE) <br />Kittitas Valley <br />(Zone) WA 12/28/2017 15:30 Ice Storm 0 0 0.00K 0.00K <br />KITTITAS VALLEY <br />(ZONE) <br />Kittitas Valley <br />(Zone) WA 1/17/2017 15:00 Ice Storm 0 0 0.00K 0.00K <br />EAST SLOPES <br />OF THE <br />WASHINGTON <br />CASCADES <br />East Slopes <br />of the <br />Washington <br />Cascades <br />WA 12/4/2014 15:00 Ice Storm 0 0 0.00K 0.00K <br />E KITTITAS <br />(ZONE) <br />E Kittitas <br />(Zone) WA 1/17/2005 03:00 Ice Storm 0 0 0.00K 0.00K <br />E KITTITAS <br />(ZONE) <br />E Kittitas <br />(Zone) WA 1/8/2004 22:00 Ice Storm 0 0 0.00K 0.00K <br />TOTAL 0 0 0.00K 0.00K <br />