Updraft: July 15, 2009 Archive

Biggest severe weather event of the season pounds Minnesota

Posted at 8:25 AM on July 15, 2009 by Paul Huttner (1 Comments)

A rainbow graces the skies near Tracy, Minnesota last night.
MPR photo by Mark Steil.

That was a good one.

Long-lived supercell thunderstorms hammered central Minnesota Tuesday. The two part event featured tornadoes and funnel clouds on the southern edge, along with a heavy rainfall event to the north. Over 4 inches of rain drenched the Brainerd Lakes area as multiple storm waves moved through central Minnesota.

This was not your average severe weather event for Minnesota. Weather conditions featured an intersecting warm and cool front west of St. Cloud Tuesday. As the heat of the day built up, a strong upper wave ran over the top of the frontal zone, triggering the storms. Your average thunderstorm life cycle is about 30 minutes. The supercell that formed near Spicer Tuesday lasted over 6 hours. After dropping the tornado that caused damage in Spicer and near Green Lake, the same storm went on to produce flooding rains and multiple funnel clouds in St. Cloud.

St. Cloud dodged a bullet last night. The storm was showing rotation on doppler right over the city. It was very close to dropping another tornado similar to the Spicer tornado. That likely would have caused much more widespread damage in St. Cloud.

To the north, several waves of storms battered the Brainerd Lakes and the Bay Lake areas. Flash flooding occurred in those areas with 3 to 6 inches of rain in just a few hours. That's half a summer's rain in one evening. I think it was Mark Twain that said, "It takes a flood to end a drought." Three to six inches of rain will put a dent in drought conditions in those areas.

Here in the Twin Cities most areas got skunked again. The northeast metro got some much needed rainfall, but most other areas stayed dry. Most counties in and near the Twin Cities still have yet to see our first severe weather warnings of the season. At least there's a silver lining.

Look for a chilly end to this week before another nice weekend comes our way.

PH

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Fairbanks, Alaska warmer than much of Minnesota this July

Posted at 3:59 PM on July 15, 2009 by Paul Huttner

You would think it would be a safe bet that a Minnesota summer would be warmer than Alaska. This July you'd be wrong.

Take Fairbanks, Alaska. There have been 10 days so far this month at or above 80 degrees. In the Twin Cities? Only 9 days. Fairbanks cooked at 91 degrees on July 8th. In the Twin Cities that day? A cool 79 degrees. In fact the Twin Cities has not hit 90 yet this month.

Daily maximum temperatures have been warmer in Fairbanks than in the Twin Cities on 9 of the 14 days this month. Fairbanks is running 5.4 degrees above average for July at 68.4. The Twin Cities is running 1.7 degrees below average for the period.

It's not even fair if you compare Duluth with Fairbanks this month. The average temperature in Duluth is 62 degrees this month. That's a full 6.4 degrees cooler than Fairbanks this month.

So why is this happening? It would be nice to have an easy explanation like the developing El Nino, but the reality is we just don't know. A high amplitude jet stream pattern has put Alaska under a warm ridge of high pressure this month. Minnesota has had frequent northwest flow bringing cooler air from Canada. It's just one of those things unless and until somebody produces a study of finds a pattern that can make sense of what we observe as "weather chaos."

Many people from Minnesota are snowbirds and move to southern climates like Florida or Arizona in winter. This month makes you wonder if we should move north to Alaska in summer.

PH