Tuesday, April 16

Chicago’s Lousy Spring

By Andrew Spaulding

All of us boaters are suffering from the lack of spring 2013. Boat chores aren’t getting done. It's too cold outside (still!!) to finish gelcoat and paint work. Wax is clumping up instead of buffing nicely into the topside. It seems like everyone isn’t quite where they want to be for their spring launch. I wanted to do some research into our continuing lousy spring. So with a little help from Google, I found out that we shouldn’t be holding our breath while we're waiting for the spring of last year to arrive. Our problem so far has been the Greenland Block.

The Greenland Block is an atmospheric phenomenon that has occurred more often recently with warmer global temperatures. In March a high-pressure weather system over the Arctic brought higher than normal temperatures to Greenland while pumping cold air down to the mid-west and the eastern United States. Essentially, the blocking high over Greenland forces the usual Westerlies aloft, which over North America are known as the jet stream, into a very southerly route which exposes the eastern 2/3 of the United States to Arctic air (see picture).

The air flowing down from the Canadian Arctic got a little help to stay cold when it arrived over the United States. The snow pack from the Rockies across the northern Plains and Upper Midwest covers twice the area that it did last year. The good news is that lower soil temperatures should help lower the evaporation rates early in the season which will help Midwest farmers recover from last year’s drought.

One of the reasons for our great spring last year was a lack of spring thunderstorms. The meteorologists from Accuweather say that thunderstorm activity this spring should return to more normal conditions. From the look of the 10-day forecast, they are correct. We have rain or thunderstorms forecast once every few days (or more often!) for the 10 day forecast in front of us now.

NOAA publishes seasonal outlooks at three month intervals. The seasonal outlook for our area for April – June 2013 has a 40-50% probability that our temperature will be above average. This, I am all for…unfortunately, the seasonal outlook says that there is a 40% probability that we will have above average precipitation. So, I’m planning on getting some use out of my warm weather rain gear. On the bright side, I’d rather have warm rain than cold rain!

The other identified causes of peculiar weather, El Niño and La Niña, are in neutral conditions so far this year. This means that surface temperatures are near average across the Pacific Ocean. For us this means that we shouldn’t have any influence by either El Niño or La Niña, so our weather averages this spring and summer should be close to their long-term averages. Last spring was my first one in Chicago, so someone (hopefully with a good memory) is going to have to tell me what that means.

Thanks to AccuWeather.com, NOAA, NASA and the Chicago Tribune for the research into this spring’s lousy weather.

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