Monday, January 22, 2007


Where have I been the past week? I, along with thousands of other meteorologists converged on San Antonio for the 87th annual meeting of the American Meteorological Society (AMS). The AMS consists of meteorologists who are scientists and researchers, government employees and of course, broadcasters. Approximately two hundred of my brethren attended training classes and gave presentations on trends in our industry and examples of how we cover various severe weather episodes.

It is an AMS tradition that strange weather occurs in the city where the annual meeting is held. This year was no exception, as an ice storm arrived in the Alamo City. Nearly everything outside of the main loop around town (similar to our I-285) was shut down and schools were closed. The normally busy shops and restaurants that line the picturesque Riverwalk were vacant as natives bundled up as best they could. Freezing temperatures arrived on Monday morning and didn’t lift until mid-day Wednesday.

In many ways, the ice that formed in San Antonio happens in a way that is similar to the kind of ice we can get in North Georgia with one notable exception. To get ice, you need two ingredients – low level moisture at around 3 to 5 thousand feet and cold air at the surface. This way, rain falls out of the clouds, but it freezes when it collects on surfaces at the ground, like trees, highway overpasses, etc. Its one of the most deceptive weather threats because it looks like its just raining. The icing occurs over the course of a few hours and before you know it, everything is covered in a cold glaze. San Antonio sits just south of an elevated piece of land called the Balcones escarpment. Cold air coming in from North Texas will cool and sink as it flows south of the escarpment. In Georgia, we sit at the tail end of the Appalachians and our cold air source comes from a wedge of air that is pushed down the east coast that banks up against the Appalachians.

Having lived in Texas for a number of years, I know how beautiful San Antonio can be, but this time around, it was a kind of winter wonderland.

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