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Derecho, summer windstorms – looking back (10yrs)

I moved back to the Twin Cities from Duluth, MN last September to help Paul Douglas start a company called WeatherNation. Of course, I was excited to be back home with family and friends, but more so to be where the action was at. I’m talking thunderstorms, with flashes of light and rumbles of thunder. A nice low roar to help put me to sleep at night. To my surprise, thunderstorms have been few and far between this year and in fact, the record for the latest tornado in Minnesota ever on record (since 1950) stands at June 23rd, 1952 – only a few days away. Storms have been nearly non-existent this year thanks to a prevailing northwesterly wind from Canada, ushering cooler air from the north. Storms are expected to make a return through the rest of the week with the severe potential creeping northward. So far, severe storms have stayed well to our south and last Friday, June 12th, a long-lived, straight-line wind storm (called a derecho) raced through the middle part of the country causing major damage across 7 states. The storm cluster actually began in the late evening hours on the 11th in Colorado, but gained momentum as it proceeded southeastward through the mid Mississippi Valley.

First of all, take a look at this incredible video from Memphis, TN (captured on Friday, June 12th). This is what nearly 100mph surface winds look like on video; equivalent to an EF1 tornado or category 2 hurricane.
Above is the damage path… below is the monster that created the, nearly, 300 storm reports.

This is what the Radar out of Little Rock, AR looked like on Friday at 4pm. Notice the backwards “C” shape to the storm complex or the boomerang shape to the intense orange and red colors. This is called a “bow echo” and since it was such a long-lived storm it is better known as a “derecho” (Spanish for “straight”) Another look at the same radar image with additions. Storms like this gather steam as cold, dry air aloft, plummets to the ground. The strongest of the winds at the surface tend to occur where the pinkish purple circle is drawn (at the nose of the “bow echo”). This is exactly what happened nearly 10 years ago in the Boundary Waters in northern Minnesota on July 4th, 1999
Doppler Radar from the Duluth, MN on July 4th 1999 below:
More information on the Boundary Waters Windstorm can be found here courtesty the National Weather Service in Duluth, MN

Hey, speaking of Duluth:

This will be the first year in four years that my wife, Sheena, and I won’t be in Duluth, MN for Grandma’s Marathon weekend. We’ve participated in the event the past three years, completing the half-marathon twice and the full-marathon once. Good luck to all the runners this weekend and a big thanks to all the volunteers that MAKE Grandma’s weekend happen. It is a big operation/undertaking and it wouldn’t be the same without you.

Weather Headlines

* Good chance of showers/storms Tuesday.

* Break in the showery pattern Wednesday midday into Thursday afternoon.

* Next chance of organized showers comes late Thursday into Friday.

* Saturday rain may linger over Wisconsin, clouds and showers can’t be ruled out over far eastern Minnesota.

* Sunday appears to be the sunnier, warmer, drier day of the weekend, statewide.

* Long-range guidance: highs mostly in the 80s the last full week of June. No more cold fronts in sight.

Todd’s Outlook

Today: Mostly cloudy, showers likely, even a heavier T-storm or two. High: 73

Tonight: Showers and storms possible overnight. Low: 59

Wednesday: Damp start, then becoming partly sunny. High: 74

Thursday: Sunny start, clouds increase PM hours. Some rain moving in late. High: 76

Friday: Unsettled with a few widely scattered showers. High: 74

Saturday: Mix of clouds and sun. Showers should stay well east of the St. Cloud area. High: 76

Sunday: Nicer day of the weekend. Sunnier and warmer. High: 82

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