Minnesota derecho moved at 50 mph

One week ago Monday night an intense and damaging derecho tore across northern Minnesota. Extensive wind damage blew down hundreds to thousands of trees and damaged docks, boats and homes.

The National Oceanic and Atmospheric Administration's Storm Prediction Center studies such events. Here's a nice look at the history of the July 21-22 Upper Midwest derecho. Note the forward speed, near 50 miles per hour.

So far 20 tornadoes have skipped across Minnesota in 2014. Thankfully no major towns or cities have been in harm's way. Most of the twisters have favored open country in western Minnesota.

Nationally tornado numbers (854 so far) are running above last year's record low pace, but below the longer term average.

So far we've been pretty lucky for severe storm season 2014. Flooding has caused much more significant damage in Minnesota this year.