Friday, May 8, 2009 (North TX, 475 mi.)

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Extreme instability and marginal shear ahead of a cold front produce unremarkable borderline supercells/multicells.

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Brandon, Bryan and I left Norman around 1pm to take a chance on something mildly interesting unfolding ahead of a slow-moving cold front approaching the Red River, S of which existed a moist and highly unstable airmass. Flow in the mid- and upper-troposphere was absolutely anemic, but this was also the case on a couple other recent days that turned out worthwhile. The problem was that no outflow boundaries existed to conjure up any magic this time. We got down to Gainesville on I-35, at which point a pair of interesting-looking supercells were evolving W of Ft. Worth, significantly farther S than we had planned on chasing. To make matters worse, they were moving almost due S, having turned right almost immediately after initiation. We hedged SW to Decatur to keep our options opened if the cold front somehow failed to initiate convection near and N of the Red, but no sooner had we arrived than the entire length from Jack Co. up towards ADM lit up like a Christmas tree. We reversed course and met up with the strongest updraft near Nocona. It had to be about the ugliest, most unremarkable storm I've seen in >3000 J/kg SBCAPE (maybe the stuff on 2008-05-13 could give it a run for its money). As it drifted SE towards through Montague Co. to the S of St. Jo, we followed it until sunset, at which time we headed into town and got Subway. When we finished, a couple new storms (non-supercellular) were located just to our N along the river, and we wasted some time looking for large hail (unsuccessfully) while they pulsed up and down. We made it back to Norman a little after midnight.