The Northeast and the Great Lakes regions could be in for a cool and pleasant summer, with temperatures below those of last year, according to forecasts from the National Oceanic and Atmospheric Administration's Climate Prediction Center and other experts. That won't be the case across the country, however. Temperatures are predicted to be higher than normal in the south, central and western parts of the U.S.

One of the major contributing factors to the predicted cooler summer for some regions is the late winter in the Great Lakes region, where currently about one third of the lakes are still covered in ice. In previous years, when the ice lasted this late into the season, winter tended to be followed by cooler-than-normal summers in the central and eastern parts of the country, a situation echoed in corresponding regions of Canada. It's not the ice itself that causes the cooler summers but the winter weather patterns that cause the ice to form and remain so late into the spring.

Although the overall trend for the past few years has been less ice on the Great Lakes, this particular year bucks the trend. At this time last year only 6 percent of Lake Superior still had any ice coverage. This year more than two-thirds of the lake remains iced over. "It's quite unusual," Great Lakes Environmental Research Laboratory scientist George Leshkevich told Canada's CBC News in Thunder Bay.

The effect will be felt several states away from the Great Lakes. The Washington Post's Capital Weather Gang looked at past years and calculated that the District of Columbia's summers were "near normal during the icy winters and about 1 degree above normal during the ice-less winters." The Post's meteorologists link this to high-pressure systems over Alaska and low-pressure systems over Canada's Hudson Bay – some of the same patterns that created this past winter's polar vortex.

The cooler summer won't be extreme. Michigan Live meteorologist Mark Torregrossa said his state's history shows that the previous 11 cold winters led to summers that were an average of 1.2 degrees below normal – just enough to save us a few pennies on our air-conditioning costs this summer.

That doesn't mean the country as a whole won't feel some impact. Leshkevich pointed out that the late winter on the Great Lakes could have "economic, society and ecological" impacts. Most notably, he points out, the shipping industry had to wait a few extra weeks to really get started this year. But while that industry may suffer a bit, fish could benefit from having more ice because it can protect their spawning beds. Whitefish, in particular, could benefit – good news following this year's Passover gefilte fish shortage.

But there is, as the Capital Weather Gang puts it, a wild card in all of this: chances of an El Niño weather system developing this year are greater than 50 percent, which could throw the whole system out of whack. Oh boy.

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Cooler summer predicted for Northeast, Great Lakes
But the central and southern parts of the country could experience hotter-than-usual temperatures.