Floods and Fires
Listen in RealAudio
Email your weather question

Hi, I'm Bryan Yeaton and this is the Weather Notebook. Floods and fires are the two biggest natural disasters in the Rocky Mountains, and they've got more in common than you might think. Here' s correspondent Bob Henson from Boulder, Colorado, to tell us more.

Tonight a strange south wind is howling past my window. It's laden with dust, and it's holding a faint whiff of smoke, the sign of a forest fire somewhere in the mountains to my west. We've been in the grip of a ferocious drought through most of this year. That makes a lot of people nervous, especially the people who live in alpine forests that could disappear with a single spark in the wrong place. A friend of mine took her family photos out of her mountain house and stashed them in her office just to be safe. But as bad as a wildfire is, there's a sequel to worry about. Once a fire burns out, it can leave behind a slick residue that clings to the ground beneath the tree stumps. It's as if the land were oiled down. The next time it rains hard, water rushes down the hill far more quickly than it could trickle through the forest. Fire scars are notorious for flash flooding. And our climate can swing from drought to flood before you know it. About 40 miles southwest of my home, in 1996, a springtime forest fire burned more than ten thousand acres near Buffalo Creek. Then, on July 12 of that year, a thunderstorm parked over the canyon. Before long, a flash flood was tearing down the hillside. Among the buildings hit by the flood was the local firehouse, the same one that buzzed with activity on a dry, hot day in May just two months earlier. Fire and flood. They even sound like siblings, but not the kind you'd want to meet in a dark canyon on a night like this.

Bob Henson lives in Boulder Colorado. The Weather Notebook is a production of the Mount Washington Observatory. It is supported by Subaru and National Science Foundation.