A layer of smoke blanketed Austin this morning. But it wasn’t, as some people may have feared, a fresh wildfire down their block. It appears that a weather event caused the smoke from a 34,000 acre wildfire in Bastrop County to descend on the Capitol City.
“My best guess right now is this is smoke that originated generally from the Bastrop County area and got trapped underneath the inversion, which set up in the overnight hours,” Lower Colorado River Authority meteorologist Bob Rose told KUT News. “That’s when temperatures near the surface cooled off more than the atmosphere just above it, so as that smoke hit that inversion layer, it really kind of spread out in all directions.”
“As that smoke hit the inversion layer, it really spread out in all directions,” Rose said.
Wikipedia has this explanation of meteorological inversions, and this TV meteorologist from Birmingham, AL explains inversions using an animation.