Near the western Oklahoma border, we broke out of a thick deck of low stratocumulus and the temperature jumped. We arrived at the interchange where Hwy 70 goes south to Clarendon and surveyed some high-based thunderstorms that for some reason were barely clinging to life. It could have been that the strong heating west of the cloud deck had mixed out too much low-level moisture, but we weren't sure. Regardless, a supercell had formed between Amarillo and Lubbock, and it was becoming clear from radar data that that storm was our only chance of seeing anything worthwhile before dark.
The Texas Panhandle is not the iron-flat, grid-road holy land of storm chasing I once thought it was. That does exist on the Llano Estacado, the high plain west of the Caprock Escarpment. But the eastern half of the Panhandle is dominated by river valleys--the Canadian and the forks of the Red--all of them extensive obstacles for chasers. We found ourselves stuck southwest of Clarendon on the rim of a wide, shallow valley where the Prairie Dog Town Fork and its tributaries flow (at least when it rains). The supercell churned behind the opposite rim of the valley, maybe 20 miles distant. As the sun sank along the storm's southern flank, it provided adequate contrast for us to see a rain-free base with fingers of cloud reaching down, moving around, and changing shape. At such a distance we could only speculate about what we were seeing.
Desperate to intercept somewhere before nightfall, we backtracked to Clarendon and headed northwest on U.S. 287, a wide open stretch of highway with which we'd become familiar on a PECAN deployment in the summer. With the storm moving northeast, we pushed on until we approached the forward flank. A funnel appeared in front of us and reached toward the ground; by the time we pulled over, it had almost retreated back to the cloud base. Other chasers confirmed a brief tornado.
We stopped just short of the RFD gust front at Goodnight (where Charles Goodnight of the Goodnight-Loving Trail is buried) and observed for a few minutes before turning north on Ranch Road 294. The outflow was bearing down from the west, a second storm was forming behind ours, and darkness was gathering. By lightning we saw things beginning to happen far to our north-northeast and pulled over. The first photo had to be brightened a lot and shows a pronounced clear slot wrapping around the incipient funnel cloud. Rain and wind slammed us while we tried to document the tornado. It's not visible in my photos, but we saw a debris cloud at the surface backlit by lightning. Addison called it in to NWS Amarillo. This tornado was very close to Groom, the target we had set in Norman and the site of my 16 April tornado intercept.
This tornado dissipated and we continued north to I-40, on which we headed east. The supercell was gaining forward speed and we weren't sure how long we could stay with it, or if we'd be able to intercept again at all. But as we went east through Groom and Alanreed, lightning allowed us to view another tornado maturing to our north. It grew from a cone into a stovepipe and persisted until it moved out of view. Addison called AMA again. We didn't take photos, since there were few stopping places on I-40 and we hoped to catch the storm again. Watching radar, we continued to eye a second storm right on the heels of the first.
We turned north at McLean, TX, on Hwy 273. The first part of this highway was straight and desolate. This was the little Pontiac's first storm chase, and it got to stretch its legs with storms racing away from us at 50+ mph. We caught a break, though: the second storm organized quickly and produced a tornado. The velocity signature wasn't immediately obvious as it was passing near a wind farm, but one scan showed a long faint hook in reflectivity and the next showed a high-reflectivity ball at the end of it. We decided to let the lead storm go, even though the tornado we'd seen from I-40 was now a monster near Pampa, and play the closer one.
The road turned northwest toward Lefors and Pampa. Coming over a rise, we saw the wedge on the lead storm far to our north. By the time we got out and took photos, it had all but disappeared over the horizon, but at least the top of a big tornado is evident.
There was a single power flash to our west with the new tornado as we flew northwestward. Where 17 Road meets Hwy 273 just north of Lefors, we got our best look at Pampa tornado #2 as it moved along the southern fringes of Pampa about eight miles to our northwest, doing EF-3 damage. Rapid rising motion along the edges of the condensation funnel was visible even by lightning. It was the strongest tornado either of us had seen in person to date, with peak winds estimated at 155 mph and a maximum width of 750 yards. AMA got a third phone call and a tweet, but everyone in the Panhandle knew what was going on by that time.
We decided the storm, which was still blasting northeastward at highway speeds, was worth following farther into the night. Getting to the southwest-northeast U.S. 60 would offer us a chance to stay with it. The northward jog on the gravel 17 Road was hairy at times. The remote farmland was extremely dark, and sharp curves caught me by surprise. We were lucky to stay on the road. Driving on unfamiliar roads in a hurry, distracted, and/or at night is a greater danger than the storms, especially for conservative chasers. After thumping over several cattle guards, we emerged on Hwy 152 and cut over to U.S. 60 east of Pampa.
At this point we became concerned. Emergency vehicles with lights flashing were hurrying back and forth. It was evident that significant damage had occurred somewhere. We later learned that the tornado had destroyed a Halliburton plant less than five miles west of the intersection. Just after turning northeast on U.S. 60, all at once we noticed power lines lying on the road, a defoliated tree, and the pungent smell of freshly ripped grass. In hindsight, this was likely the track of the first Pampa-area tornado, not the second. Seeing no structures in the area where our help might be needed, we continued behind the storm. Lightning periodically showed us a large tornado; a damage survey would conclude that the Pampa tornado had actually dissipated and we were following a new one.
We stopped somewhere near Miami for a final view. Far off on the horizon, there appeared to be two tornadoes side by side.
The town of Canadian, farther northeast on U.S. 60, marked the end of the chase. We were running low on gas and unable to make out any more interesting features on the storm. We dropped south to get gas and snacks in Wheeler, then raced through Shamrock to I-40 as a congealing QLCS spun up weak mesovortices all around us. Even with a speed limit of 75 in the Panhandle, not until the Oklahoma border was there a comfortable cushion between us and the leading edge.
Per NWS Amarillo's final public information statement on the event, nobody was injured in these tornadoes, even though two EF-3s brushed Pampa. Photographically it was a rough night, but it's impossible to complain about catching nocturnal wedges in November. No tornadoes as strong as these had ever been recorded so far west and so late in the year. Five or six tornadoes in a day is also a personal best.
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