The story goes that when Jule Gregory Charney, at Princeton's Institute for Advanced Study, ran an early numerical weather prediction in 1953, he and his colleagues managed to correctly hindcast a big snowstorm that had hit Washington, D.C., the previous year (fooling forecasters at the time). The quotation above is what Charney apparently said in a late night call to Harry Wexler, research director of the U.S. Weather Bureau. The moment has come to be regarded as a kind of turning point in meteorological history. I couldn't help thinking of those words as our first snowfall--or at least, the first to which I've been a witness this winter--arrived in D.C. less than an hour ago. I've been living here 5 years now, and I don't remember a year in which the first snow came so late. Neither do I remember anything analogous to the seriously balmy days that have preceded it in recent weeks, one of which forced me to go home to change clothes because I'd dressed too warmly. None of which is to say that my memory is trustworthy on such matters of past weather. My anecdotes can be more or less ignored, but the fact remains that weird winter weather has generally been a persistent theme of the past several months, across the country and the world. Weather in one place is never "global warming." But rightly or wrongly, weird weather in enough places will surely help convince the public that something is afoot--thus adding still more momentum as we head into what I suspect will be a pivotal year for the climate issue...