Fall is in full swing, and while most of the country experienced a very summer-like start to the season, that's changing this week.

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A large cold front is moving across the eastern two-thirds of the country, bringing in some cooler, fall air.

This round of cooler air likely won't last long, though.

Long-term forecast models have warmer than average air returning to the eastern half of the country as cooler air moves into the western half.

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