Not to be outdone, NBC's new web site has an article on warm summer nights proving Global Warming.
A top federal research meteorologist said he "almost fell out of my chair" when he looked over U.S. night minimum temperature records over the past 96 years and saw the skyrocketing trend of hot summer nights.Maybe he would have kept his seat if he had heard about urban heat islands . Forests and farms tend to be cooler and to lose their heat faster at night. Buildings and roads soak up the sun and radiate it back at night. You can verify this for yourself - just put your hand or a bare foot on a driveway after dark. It will be warmer than nearby grass.
This effect can cause a local shift in temperature of 2-10 degrees - equivalent to moving a hundred miles south. As our cities expand, it would be amazing if nighttime temperatures did not climb. But that wouldn't scare people.