Bad Weather? Blame The City

"Scientists have known for 200 years that the temperature in a city can be higher than that in its environs....Hot city air, like hot air anywhere else, rises — even more so because of the turbulence caused by tall buildings. When that air is damp enough and collides with colder layers above it, water can condense out as a sudden burst of rain, especially if there are few frontal systems to disrupt the layers, as in summer. In a spot storm above a city or just downwind of it, it's likely that nature alone isn't behind the downpour....Hot, waterlogged cities can be cooled off in the usual ways — by limiting auto exhaust, for example. Using light-colored roofing and paving materials in place of black, heat-absorbing tar will also help."