Precip Can
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Hi, I'm meteorologist Dave Thurlow and this is The Weather Notebook. Part of what a meteorologist does is observe the weather. And what better place to do that than atop New Hampshire's Mount Washington, where, with weather, there's plenty of it. On a recent visit to the summit, I explained to some visitors about low tech, but highly accurate weather technology.

"It's basically, well, it's a round cylinder, one end closed, the other end open. The technical term that we use for this is a can. And then we put it outside, expose it to the precipitation. Let it sit for six hours. Then bring it back in and take this other very high tech piece of equipment that we have um, called a ruler. And we stick it in the can and measure it. And whatever comes up to one inch we have one inch of rain."

Of course, one weather element affects another, and on Mount Washington, the wind can be a bit of a problem. But wind and other less natural phenomenon notwithstanding, the precip can is still the way to go.

"Many a graduate student has spent probably too much time trying to figure out exactly what the capture rate is according to the wind speed. The way we figure it is, we can't control the wind so we just have consistency in our data.

This can has always been sitting in the same place, outside on the summit and we don't try to filter out anything like, like chunks of ice or anything like that. If it's in the can, it's precipitation. That's the way we look at it. We can measure the snow and the rainfall in here, too. In the winter we just take the snow inside and melt it. And that's how we get what's called the melted precipitation, and if there's anything in that besides cigarette butts or coffee cups, we'll filter that out. And if it's clear liquid we'll measure it as rainfall."

Low technology works just fine, even on a high summit. Funding for The Weather Notebook comes from the National Science Foundation, with support from Subaru, the beauty of all-wheel drive.