If A Little Farther

April 30, 2009 by
Filed under: Journal Entry 

Supercell near Matador TX, and Other Storms
20 Apr 9

SHORT: Intercepted briefly sculpted supercell N of Matador TX, under anvil of another storm farther W that produced a tornado that we saw, but didn’t realize was such due to distance. Observed HP merger and evolution of resulting “Pac Man.” Drove back in great light show.


After getting off shift and getting enough sleep to chase safely, I looked at a little data and called Rich, who was off and agreed to join me on what looked like a marginal shear/large CAPE setup. The target area was the outflow boundary from the morning MCS, sunny and cooking well on both sides, in NW TX. At last, the Two ChumpsTM were on the road again, brother, and ready to partake of the smorgasbord of atmospheric violence.

We left Norman shortly before 1330 CDT (1730Z) and took the I-44/US-62/US-183 zigzag to Vernon, through the cold, stratus-enshrouded outflow pool and past numerous flooded fields drainning with active runoff. [it was great to see SW OK so wet and green, for once!] While refueling with both gasoline and the usual regional snacks, a supercell already was apparent along the NW-ward curving segment of the boundary near Estelline, too distant to get to without interference from a newer storm going up to its SE.

Headed WSW out of vernon on US-70, we noticed the anvil from the southeastern “Dunlap” storm was getting rather robust, and the radar presentation looked decent with unimpeded inflow. It could have been a case where having onboard radar hurt us, in 20/20 hindsight. This was the “sucker storm” along the way to something better, and we fell for it. Naturally, had we known that, we wouldn’t have bothered.

We detoured N almost to Crowell then WSW toward Paducah to take a look, and while we measured low 70s temps in what had been its inflow region, the storm crapped out right as we got there. Hardly anything was left but fall streaks, beneath the thickening and spreading anvil of two newer supercells NW-W of Matador. The eastern of the two (Matador storm) was closer to us, very near the western segment of the old outflow boundary, all by itself (for a little while anyway) and crawling eastward very slowly in order to maximize its low level SRH on the hodograph. Sweet!

We roared W almost to Matador then NNE on FM-94 to get into the immediate inflow sector of the Matador storm. We could see it was under the thick anvil of yet another storm farther to our W, which was producing a copiously arching outflow boundary on reflectivity imagery. The western storm was the “Cedar Hill” tornado producer, despite all that outflow and unknown to us at that moment.

We saw a smooth-sided lowering from cloud base to apparent ground level way off to the WNW, under what seemed at the time to be either a very scuddy, ragged updraft base or rear-flank gust front with the “Cedar Hill” storm. We laughed at it, unable to see rotation at such distance (~15 miles), and knowing the storm was producing lots of outflow. Well, it also was producing a fat tornado, and that turned out to be one. Looking back at my phone and GPS logs, this perfectly matches one of the tornado report times.

This video capture, posted to Storm-Track by Matt Chatelain, shows what it looked like to us, but a little more distant, with some slight terrain rises and mesquite trees in the way — just enough to cast doubts. Our viewing angle and lighting were very nearly the same.

Of course, reviewing the facts post-mortem removed all doubts. Again, what’s that hindsight vision? We were driving up to the Matador storm and not taking photos of that feature far to the W, but had I bothered to stop, slap on the zoom lens quickly and shoot “just in case”, I would have had my first (very distant) tornado shot of the year.

The closer “Matador” storm beckoned, its base already visible with a bell-shaped structure above. We found a good parking spot and vantage at the entrance to the Stitch Ranch, soon joined by our forecasting colleague Jonathan Garner, then a few moments later, none other than the father of storm chasing himself, Dave Hoadley.

It was great to chat with Dave and Jon during our short time at the Stitch Ranch gates. We admired the nice structure above an elongated cyclonic shear zone at cloud base. Occasionally smaller areas of rotation would develop, but tornadogenesis never appeared imminent, despite being in an environment that didn’t seem appreciably different (except for having less outflow) than the “Cedar Hill” storm. Here’s a shot of the eastern side of the supercell, looking N up FM-94, showing the sinewy curvature of cloud banding with this storm.

Rich and I then cruised N a few miles to get closer to the occasional areas of cloud base rotation before the storm got E of FM-94 and into a gigantic road void. As we did, the bigger, faster-moving and more outflow-dominant “Cedar Hill” storm began to encroach upon and seed the hell out of the our supercell. That gave it more HP character, lowering light levels ominously, and turning it into a more prototypically North Texas MUN (mean, ugly, nasty) stormzilla. We bailed S to get back to US-70, taking one more look back through the turbulent and eerily colorful “whale’s mouth” and consigning the conjoining supercells to HP-from-hell status.

A left-mover developed in situ to the SE of the combined “Pac-Man” supercell (shot from Jon Garner), then split in its own right, the continuing left member being drawn into the forward flank of the cyclonic HP monster as we hurtled E in a thread-the-needle maneuver between them. Meanwhile, the rotation in SRM imagery got very intense and tight somewhere out there in the mesquite brush to our N and NW as we headed back to Paducah, but good luck seeing anything in the deep, dark murk!

We tried to circumnavigate the growing area of elevated nocturnal convection by driving E to SPS then N through FSI, but hit heavy rain and a barrage of CGs around FSI anyway. It brought back memories of our many chases from the late 1980s down to NW TX, then back on I-44 through rain and lightning bombs. The crawler show on the N side was fantastic when they did erupt, but very sporadic and intermittent. I stopped just W of CHK for lightning photography, trying the 17 mm wide angle at slightly higher than usual F-stop. This was in effort to catch some of the insanely bright crawlers that would sparkle nearly overhead from the MCS to our SSE, then slam a CG miles behind us with a deep, long, window-rattling report of thunder. I missed the best crawlers between shots and while setting up, but did get a few more distant crawler+CG combos.

If we had left earlier, if we hadn’t gotten sidetracked with the “Dunlap” storm…well, we might have seen the tornado from closer with much more confidence and certainty…or hit some fat, stupid cow and ended the day upside down in a flooded ditch, slurping mud and crying for mommy. Who knows? As we’ve said before: “If ifs and buts were candy and nuts, it would be Christmas every day.”

We got back to Norman fairly satisfied with the chase, tornado or not, having seen a sculpted storm and a fascinating morphology and interaction process. All in all, it was a worthwhile trip for such a distance, considering the constraints imposed by sleep rotation from evening shifts to overnights.

Three remarkable non-events happened on this chase that are absolutely amazing, if you know either of us:
1. Rich didn’t blow a head gasket and launch into a tirade the whole day!
2. I didn’t fill the car interior with buttgas even once, despite consuming two Allsups burritos!
3. We didn’t hit a single red light from Matador to my house in east Norman, including all the usual unsynchronized flytraps along Highway-9 around south Norman!

The odds of all three of those must be as low as the odds of seeing a fat tornado in a different county from NNE of Matador, and not believing it at the time.


Comments are closed.