Heat Lightning
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Prior to America's entry into World War II, only two women were listed among the US Weather Bureau ranks as observers and forecasters. But during the war this changed dramatically. By 1945, over 900 women worked as observers and forecasters . Many weather offices were comprised almost entirely of women.

Women in the Weather Bureau During WW II NOAA Photo

Hi, I'm Bryan Yeaton and this is the Weather Notebook. Sometimes even the most astute weather observers are brought down to earth by the facts, as commentator David Laskin learned.

I have a wonderful memory of lying awake one muggy summer evening in a cottage off the coast of Maine and watching heat lightning flicker like enormous fireflies on the western horizon. "It's not really lightning at all," I assured my wife dreamily, "but an optical display caused by the discharge of hot air. Notice how there's no thunder? It's our version of the northern lights."

Great memory - too bad my explanation was totally off base. A quick Internet search reveals that heat lightning is really no different from ordinary lightning - only it's so far away that you don't hear the thunder. Those silent flashes that looked so romantic through our cabin's gauzy curtains were booming away like cannons on someone else's vacation. Another cool tidbit: heat lightning often looks pink, not hot white like ordinary lightning. Again it's because of the distance - as light travels, air refracts or bends the shorter wavelength blues, so the flashes that reach a far-off observer appear rosy.

I was also pleased to discover on the Net that I'm not the only one who has gone a bit moony over heat lightning. I turned up a 1934 movie called "Heat Lightning" about two sisters who run a gas station in the desert, a couple of radio plays, a poem with the refrain "Lord, send your light and your rains,/I still feel your thunder in my veins." And who says scientific research is boring?

David Laskin provides commentary from his home in Seattle, Washington. The Weather Notebook is a production of the Mount Washington Observatory and supported in part by Subaru, the beauty of all wheel drive.