Manhattan, 2010.

During the run-up to Wednesday’s debate, I remember seeing kids in the background of live shots wearing shorts and thinking, “Huh. Looks pretty nice in Denver.” Friday morning, it snowed there. It snowed this week in Minnesota and North Dakota, too, in some places, more than a foot deep. The New York Times notes that such a snowfall is rare.

Well, then so much for global warming, right? Nope.

For one thing, it’s not snowing all that early for these places. For another, as we constantly note, isolated weather extremes are different from the long-term trend. And, third, some scientists are expecting a bad winter — thanks in part to global warming.

The Weather Channel has a nifty tool that shows the average date of the first snow for America’s major cities. In Fargo, N.D., the average first snowfall is on Nov. 3, a month away. But the earliest was on Sept. 25, 1912 — more than a week ago. Likewise Denver. It usually snows for the first time a couple of weeks from now, but it’s far from unusual that it should have snowed already.

That this year’s snowfalls are earlier than the average doesn’t mean anything anyway. Again, we point you to the “walking the dog” analogy. No matter how the weather is on any given day, the climate is doing the same thing: getting warmer.