I am obsessed with weather, especially in winter, and so I got this very cool weather app on my iPad. See those little snowflakes there in Illinois? As you scroll along through the hours and days it tells you what’s going to happen to those snowflakes, and whether or not they’ll reach where you live. “It” is really one model, called the GFS, or Global Forecast System; there are two or three others that meteorologists use, which is why forecasts are so contradictory sometimes.
Even just one model keeps on changing so, for example, a few days ago the GFS predicted heavy rain for the Superbowl, but as of today it looks clear – and, by the way, those snowflakes are going to be swept up into Canada, as you can probably figure out by looking at the lines.
I sound more expert here than I really am, as evidenced by my need when I first opened up the app to look up the word for all those lines (isobars) and to try to figure out what they indicated. Wind, I believe. When they’re really close together there’s a lot of wind (I don’t think I’d do too well on TV).
And the first time I saw that circle I asked Chip (who suddenly found out his senior year of college that he had to take a science to graduate and so took meteorology, a “gut” course that he never studied for, but he’s helpful in explaining how wind circulates around a low and a few other mildly useful things like that) what it was, and he said “It’s the famous Polar Vortex!”
So there you have it.