Resolution 7478 hazard mitigation

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2024 Hennepin County All -Jurisdiction Hazard Mitigation Plan Volume 2 — Hazard Inventory derecho was becoming a "high end" event. The derecho took a track similar to one of the previous nights, producing significant damage for the second night in a row from southeast North Dakota eastward across northern Minnesota to western Lake Superior. Damage was extreme across Minnesota, with over five million trees blown down and many buildings damaged, and some destroyed. Six campers were injured from the falling trees during the pre -dawn hours. Trucks with plows were needed to clear many of the roads, and some areas were without power for a week. Damage totaled well over $30 million in 1995 dollars. Extreme Thunderstorm Winds and Other Hazards, July 1, 1997 A complex of very intense thunderstorms moved out of South Dakota during the afternoon and approached the Twin Cities during the early evening, producing multiple tornadoes rated up to F- 3 (now EF-3), along with destructive winds that spread from central Minnesota into Wright, Sherburne, Hennepin, and Anoka counties and beyond. Although not long enough to qualify as a derecho, this storm was as destructive over a path that was over 100 miles long and 10 miles wide in some areas. Wind gusts estimated from 85 to 110 mph damaged small airports and planes; destroyed homes and garages; snapped or uprooted tens of thousands of trees; flipped trailers and mobile homes; blew down headstones in cemeteries; and produced over 100,000 power outages in the western and northern Twin Cities area, including Hennepin County. The storms also produced extreme rainfall rates, exceeding the threshold for 200 or even 500- years storms at the 1 and 2-hour duration, as 3-5 inches of rain occurred in 60-90 minutes. The rains overwhelmed drainage capacity across Hennepin County and stranded or submerged vehicles on parts of Interstates 94, 394, 494, 694, 35-W, along with parts of US Highways 10, 169, and 212, and literally dozens of other state, county, and smaller roads. The intense flash -flooding hampered emergency responses in the parts of the county damaged by winds. Hail Derecho, May 15, 1998 A severe squall line developed in western Texas around midnight and raced northeastward, making it to south-central Kansas by daybreak, southwestern Iowa by mid -morning, and the Twin Cities area by 16:00 local time. The storms produced widespread damaging wind along the 1000- mile-long track, and reached peak intensity in Iowa, Minnesota, and Wisconsin, with fast-moving tornadoes and 1-2" hail driven by 60-80 mph winds. This was an unusual extreme wind event, qualifying easily as a derecho, but not fitting easily into the "progressive" or "serial" categories. This is among the only known damaging thunderstorm events in Minnesota history to have originated in Texas. M