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Heat wave of 2006 derecho series

Northeastern Ontario derecho
Date(s) July 17, 2006
Peak wind gust 80 mph
Fatalities At least 1
Central Great Lakes-Upper Midwest derecho
Date(s) July 17, 2006
Peak wind gust 70 mph
Tornadoes caused 3 confirmed
St. Louis area derecho
Date(s) July 19, 2006
Peak wind gust 100 mph (St. Louis, Missouri)
Mississippi-Ohio Valley derecho
Date(s) July 21, 2006
Peak wind gust 80 mph

The heat wave of 2006 derecho series were a set of derechos — severe winds with powerful thunderstorms — that occurred on July 17–21, 2006. The first storms hit a wide swath of north-central and northeastern North America that stretched from the Upper Midwest through much of Ontario and into the northeastern United States. Another round struck the middle Mississippi River Valley, including two derechos that hit St. Louis, Missouri. The storms left more than 3 million people without power, some more than once and some for weeks.

The derecho originated from a severe thunderstorm that was forming across portions of the Upper Peninsula and the northernmost parts of the lower Peninsula of Michigan in the early afternoon hours of July 17. It crossed the North Channel into Northeastern Ontario near Sault Ste. Marie, where it quickly developed into a derecho line. As it crossed Manitoulin Island just southeast of Sault Ste. Marie in Lake Huron, numerous trees were uprooted and some homes sustained heavy damage. An official wind gust of 128 km/h (80 mph) was recorded at the Killarney weather station on the north shore of Lake Huron. Tornado warnings were issued for the area, but damage was consistent with severe straight-line winds.

At about 15:30-16:00 EDT (19:30-20:00 UTC), the storm raced through Sudbury, toppling hydro poles and trees. Highway 69, the major highway linking Sudbury and Toronto, had to be shut down because electrical wires blocked the highway. At that point, the storm system started to take the form of a comma, signature of a fast-moving progressive derecho.


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Wikipedia

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