We are now two-thirds through meteorological summer. Summer 2013 is evolving much differently than last summer. Last summer was a real warm one over a good chunk of the country (Image 1 above). This summer is much cooler in the same areas including the U.P. (Image 2 only through June). July will end just below the long-term average. This makes the sixth consecutive month with below average temperatures at the National Weather Service (NWS) near Negaunee.
It is also wetter across the Upper Midwest. Last year, the area was in the grips of a drought (Image 3). This year, the same areas are wet (Image 4). In fact, spots in the Corn Belt from Iowa into southwest Wisconsin had their wettest spring on record. This makes a huge difference in temperatures and precipitation. Dry ground can cause the air above to heat up more effectively. The hottest summers in the Midwest are also the driest.
What??s ahead? It appears that August will at least start out cool. The CFS long-range model put out by the Climate Prediction Center (a division of NOAA) calls for a vast area of below average temperatures through much of the U.S. including Upper Michigan (Image 5). If this verifies, the pattern that developed here late last winter will hang on.