 |
| Courtesy NWS Chicago |
If you were watching the radar out of the NWS offices in Chicago this morning, you probably noticed quite a bit of activity. But wait... wasn't it supposed to be dry? Where's all this rain coming from? Turns out it isn't rain. It's actually traffic. Here's the explanation.
Typically, when a radar sends out a beam, the makeup of the atmosphere will cause it to bend a little. We call this refraction. Changes in the atmosphere can lead to changes in how much the beam bends, or refracts.
This morning, we had a temperature inversion (temps warming with height) and light winds across Illinois. This caused the radar beam to bend more than normal. We call this superrefraction. The beam actually bent so much, that it was hitting the ground and picking up things like cars and wind farms!
 |
| Courtesy NWS Chicago |
Here's the same radar image from earlier. Interstates are depicted by red lines and
wind farms are outlined in yellow. As you can see, vehicles on parts of Interstates 39, 55,
57, and 80 are all visible, not to mention a couple wind farms. Pretty crazy, right?
While this doesn't happen often, it isn't unusual. Radars have been known to pick up large groups of birds and even debris from tornadoes. So the next time you look at a radar, remember... sometimes it's showing you more than just weather!
No comments:
Post a Comment