5/26/09: Anticyclonic Supercell in North Texas

Today, we started the day in Childress, Texas. It was my last day in the field coordinator vehicle, and so I was hoping to end with a bang. The day looked somewhat promising: a southern stream wave was forecasted to impinge upon a highly unstable airmass by peak heating. Additionally, a well-defined outflow boundary was becoming unstable on its cool side. I hoped that this would locally enhance the shear since environmental shear was fairly low.

We hung out in Gainesville for the better part of two hours. We socialized as we watched the weather. Most of the armada gathered at a single gas station, which I thought was a pretty bad idea (since it was difficult to exit the gas station in a timely manner). Nevertheless, we were all able to get on the road swiftly when operations began.

A supercell thunderstorm developed northwest of Fort Worth, and there was some debate among the principal investigators as to whether or not we should pursue the storm. The FCs were not exactly thrilled about the idea of chasing in an urban area. Personally, I thought the idea was ludicrous, considering my previous experiences in the greater Dallas metro area. Fortunately, good sense prevailed and the PIs left that storm alone.Later on, we targeted a left-moving storm – associated with the aforementioned supercell WNW of Ft. Worth – that was moving toward Decatur. The storm was an anticyclonic supercell: instead of spinning counter-clockwise, this storm spun in a clockwise manner. We approached the storm from the northeast, and at some point, we were able to obtain a visual on the base of the storm. Sure enough, there was a wall cloud on the north side of the storm! There was some rotation, but it was relatively slow. The low-level organization of the storm was poor, but the upper part of the storm was obviously rotating – and that, anticyclonically! It was quite a sight! Not a bad day...

Cool clouds associated with the anticyclonic supercell.