I chased a storm from east Iowa, through Madison in Wisconsin, then toward east Wisconsin. It was quite the chase; while I had no confirmed tornadoes (though there were lots of ominous-looking lowerings of the clouds), the storm was visually stunning.
I first saw tiny flecks of radar reflectivity in east Iowa. I drove back to Wisconsin to get ahead of them, because I thought they might intensify. The did, but very slowly. Meanwhile, I saw a cell getting big in central Iowa, and had a difficult decision of whether to make that my target, or keep on the tiny Wisconsin cells in the hopes that they would develop. I decided to stick with Wisconsin, since I considered that Iowa cell to be much more likely to be undercut by the cold front, it would mean a lot more driving for me, and recent HRRR runs often showed supercells developing in south Wisconsin in a favorable parameters space (though those storms sometimes faltered). I spent the next 45 minutes wondering if I'd decided my way into a bust.
Finally, as they entered Dane County, the little storms consolidated and intensified. Initially, there was weak rotation on radar, both right- and left-handed.
However, this storm was already producing hail. I drove through hail fog that looked like the ground was on fire, it was steaming so rapidly.
As the storm entered Madison, it organized rapidly. Suddenly, it had a classic right-handed supercell look on radar, and I could clearly see the RFD in person, with a horse-shoe shaped updraft.


I chased that storm right through the middle of Madison, hoping desperately that it wasn't putting a tornado down in the middle of town. (Fortunately, the lack of tornado reports indicates that the worst Madison got was significant hail.)


Just after leaving Madison, I got a good chance to slow down and admire the storm for a little.
(I got a short timelapse here that I'll put in another post due to StormTrack's media limits.)
I continued with it east along the highway.

Another supercell had developed right in front of it earlier. Since my storm was now the last in a line, I guessed that its tornado potential was decreasing. As daylight started to fade, I turned around, to head back to Madison.
There were now linear-mode storms in my path back. I didn't want to take chances, so I sheltered in a gas station and ate supper. The linear storm treated me to one last ominous-looking cloud lowering in the sunset, but I could see that this one wasn't serious.
