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A large part of the central and eastern United States can expect relatively cool conditions during June, July and August, according to the temperature forecast released by The Weather Channel Professional Division on Friday.

<img class="styles__noscript__2rw2y" src="https://dsx.weather.com//util/image/w/temperature-july-sept.jpg?v=at&w=485&h=273&api=7db9fe61-7414-47b5-9871-e17d87b8b6a0" srcset="https://dsx.weather.com//util/image/w/temperature-july-sept.jpg?v=at&w=485&h=273&api=7db9fe61-7414-47b5-9871-e17d87b8b6a0 400w, https://dsx.weather.com//util/image/w/temperature-july-sept.jpg?v=ap&w=980&h=551&api=7db9fe61-7414-47b5-9871-e17d87b8b6a0 800w" >

The forecast cites several factors that should limit big heat risks across an expansive area in the Lower 48. One of those factors is the potential development of a strong El Nino.

"The emerging El Nino event will be potent this year, likely stronger than the 2009 event and possibly rivaling the 1997 event. The downstream impacts from this event will likely drive decreased risks of big heat this summer in the eastern and central U.S., especially later in the summer," said Dr. Todd Crawford, WSI chief meteorologist. "Our current forecast for national cooling demand this summer rivals that for the cool summer of 2009, and even that may be a bit conservative."

(MORE: How Strong Will El Nino Become? )

<img class="styles__noscript__2rw2y" src="https://dsx.weather.com//util/image/w/temp-anom-1982-1997.jpg?v=at&w=485&h=273&api=7db9fe61-7414-47b5-9871-e17d87b8b6a0" srcset="https://dsx.weather.com//util/image/w/temp-anom-1982-1997.jpg?v=at&w=485&h=273&api=7db9fe61-7414-47b5-9871-e17d87b8b6a0 400w, https://dsx.weather.com//util/image/w/temp-anom-1982-1997.jpg?v=ap&w=980&h=551&api=7db9fe61-7414-47b5-9871-e17d87b8b6a0 800w" > Areas shaded in green and blue had below average temperatures June-August 1982 (left) and 1997 (right).

Two other years where a strong El Nino developed by late summer or later – 1982 and 1997 – were used as analogs for what might occur this summer. In those two years, temperatures were overall cooler-than-average across a large portion of the United States.

Another factor in the forecast for an enhanced area of below-average temperatures in the nation's midsection are the heavy rains that have occurred there this spring. This is due to the fact that higher levels of soil moisture can prevent temperatures from being hotter than they would normally be.

On the other side of the spectrum, warmer-than-average temperatures are expected in parts of Florida, the Southeast and the West. The Pacific Northwest and northern California could see temperatures much above average. This will only worsen the ongoing drought and wildfire danger in place across the western states.

Given that a large majority of the central and eastern United States are forecast to be cooler-than-average in the peak summer months, the demand for cooling nationwide is expected to be the weakest since 2009.

Monthly Breakdown

This graphic shows the breakdown of temperatures for each month separately this summer.

As you can see, cooler-than-average temperatures dominate the central states in all three months, while warmer-than-average temperatures stay entrenched along the West Coast.

In the Northeast, temperatures are forecast to be above average in the Northeast during June, and then stay below average in July and August.

<img class="styles__noscript__2rw2y" src="https://s.w-x.co/animation-temps.gif" srcset="https://s.w-x.co/animation-temps.gif 400w, https://s.w-x.co/animation-temps.gif 800w" >

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