Dickinson County Tornadoes July 27, 2010

Two EF0 Tornadoes Confirmed in Dickinson County

Thunderstorms that moved across Upper Michigan on Tuesday evening, July 27^th produced two tornadoes in Dickinson County.

The National Weather Service in Marquette conducted a ground survey of storm damage and analyzed aerial photographs provided by the Michigan DNRE. The result of the analysis and survey indicated that the storm damage in the eastern sections of Norway and one mile northeast of Vulcan was caused by tornadoes. Here is the map of the approximate track of the two tornadoes.

The same parent supercell thunderstorm produced both tornadoes. The first tornado touched down at 8:34 PM CDT on Tuesday, July 27th along 7^th Avenue in the eastern sections of Norway. The tornado crossed US2 as it moved east northeastward towards Norway Mountain. The tornado was on the ground for about a third of a mile (.33 miles) and had an average width of about 100 yards. The maximum wind speeds were estimated at 70 mph, which made it an EF0 tornado on the Enhanced Fujita scale. Several trees were knocked down or snapped off from the tornado. Some minor damage also occurred to structures from falling trees and tree limbs.

The second tornado touched down around 8:40 PM CDT in a wooded area about one mile northeast of Vulcan. This tornado was on the ground for about a quarter (.25) mile and had a width of less than 100 yards. Numerous trees were uprooted and snapped off from this tornado. The maximum wind speeds were estimated were estimated at 70 mph, which also makes it an EF0 tornado on the Enhanced Fujita Scale.



Reflectivity (top) and Storm Relative Velocity (Bottom) Images from 932 pm CDT 7/27/2010. In the top image, note the hook structure of the reflectivity. In the bottom image, the circulation from the tornadic mesocyclone can be found where the red color are outbound winds and the blue/green colors are inbound winds. Click on any image for a zoomed in look.	Reflectivity (top) and Storm Relative Velocity (bottom) images from 941 pm CDT 7/27/2010. Click on the image for a zoomed in look.



Arial Pictures from the Michigan DNRE.	Pictures of damage in Norway (courtesy Paula Petrick)