Spring is on its way, but we have to waitPublished 9:26am Tuesday, March 19, 2013
Column: Pothole Prairie, by Tim Engstrom
It’s true. Punxsutawney Phil didn’t see his shadow on Groundhog’s Day last month, thus predicting an early start to spring.
How wrong was he?
Oh, and last year, the rodent saw his shadow, forecasting a long winter. But last year, spring came early. The observed high temperature in Albert Lea for St. Patrick’s Day in 2012 was 78 degrees. There was no snow. Golf courses were opening.
This year, it was 30 degrees, and a blizzard warning was issued. This groundhog thing isn’t working. And nearly everyone I meet is dearly — and direly — sick of winter. I needed more information than the five-day forecast. I needed the long-term stuff. The real deal.
So I decided to call up our weather partners at KIMT and spoke with meteorologist Tyler Roney. I inquired when will the weather warm up.
Not for a couple of weeks, he said.
He said the weather likely will feel like spring the first week of April or mid-April. The long-term models he follows show Alberta clippers will keep storming through the region out of Canada, delivering Arctic air for at least the next two weeks. He said it doesn’t help the air temperature when there remains snow on ground.
So what was the deal with the groundhog? Why was he wrong?
“You can’t trust a groundhog,” Roney said.
Truer words were never spoken.
I couldn’t stop with Roney. I hunted around weather sources on the Internet and learned a few more details about the present state of our weather:
• There will be days above the freezing point that will melt some of the hard white snow-and-ice cover that blankets our region of the earth, but as long as the clippers keep sailing, even the weak ones, we will get snow and cold air.
• An Alberta clipper starts as a low-pressure system that forms on the leeward side of the Rocky Mountains in Alberta, the province in Canada. That system gets dragged into the jet stream and delivers snow. The slower it moves, the more snow we tend to get. It also can deliver rain or snow to places like Kentucky and Virginia. It’s what brought snow to Washington, D.C., earlier this month.
• The jet stream is the real culprit. We can blame it for our wintry weather heading into spring. Some folks might recall last spring when weather watchers were gabbing about how the jet stream traveled farther north than normal, dumping loads of snow on Ontario and Quebec and treating Europe to a long winter. (Or should I say mistreating?) The bright side was that here in the Upper Midwest we got to have sunny skies and grass under our feet. This year, the jet stream is back to its old self.
• The jet stream I am talking about is the polar jet stream for the northern hemisphere, not the subtropical one. You probably knew that anyway. This is how Accuweather.com describes the jet stream: “The jet stream is a fast river of air high in the atmosphere that marks the boundary between cool air to the north and warm air to the south. It is essentially the highway that storm systems travel on.”
• There is one thing strange about the jet stream, though. It is hanging lower than usual over Europe. They seem to be waiting for spring to spring, just like we are. However, the weather models show they should get some relief as soon as next week, when warmer Atlantic air is forecast to push through and battle Old Man Winter.
• Perhaps the most-detailed answers I could find about when spring is coming came from James Zahara of TV station WQAD in the Quad Cities of Iowa and Illinois. He explained the North Atlantic Oscillation. When it is in negative mode, high and low pressure systems that exist near Iceland and the Azores cause the jet stream to deliver cold and snow to us. When it is in positive mode, we get warm weather. Zahara writes that models show a change in the NOA should come on the 29th of March, pushing cold temperatures back into Canada. That means warm weather just might arrive in time for Easter, which falls on March 31.
Now we have something to hope for. Let’s keep our fingers crossed that the Easter bunny will deliver springtime weather at last.
Tribune Managing Editor Tim Engstrom’s column appears every Tuesday.