In elementary or middle school, my class read excerpts from Kiowa author N. Scott Momaday's The Way to Rainy Mountain. I don't know why I remember that, but that same Rainy Mountain--not really a mountain at all--poked up over the farmland to our south-southwest as we launched a balloon north of Gotebo, Oklahoma. Storms had erupted off the dryline in the western part of the state and up into Kansas. Without enough low-level directional shear for the storms' induced pressure perturbation fields to favor right-moving supercells, they began splitting. A couple left-movers became dominant, including a visually impressive one to the south.
Left-movers are notorious hailers. We bailed east and south out of the left split's baseball hail swath, trying to get into the inflow of the lone healthy right-mover within striking distance. The other crew had started farther south and made it south of the storm near Lawton, but we found ourselves coming in on the north side of the hail core. We rolled slowly through Lawton on I-44 and had to stop a couple times in half-dollar hail and zero visibility. We turned east on Hwy 7 in heavy rain and intermittent small hail with strong rear-flank downdraft winds throwing leaves and twigs all over the road. At Hwy 65, our last reliable south option for over 10 miles, we were given a green light to continue east and possibly break out of the precip.
Radar showed a tight mesocyclone moving dangerously toward Hwy 7 ahead of us. Still unable to see any features of the storm in driving rain, we decided against going farther and dove south through the hook. Minutes later, there was a small, weak tornado just a mile or two south of Hwy 7 near where we would've been. We would likely have had an ideal view of it. But continuing between the precip core and a possible tornado, without visibility, is asking for trouble; the tornado could just as easily have been on the road and hidden in rain. The mobile mesonet dataset we collected in the core and RFD leading up to tornadogenesis is probably valuable in its own right. There are always other storms--and we had no idea how soon.
Monday, May 9
When we got the chat message to turn around and come back north after launching a 3 p.m. weather balloon behind a gas station at the Marietta, Oklahoma I-35 interchange, I had never seen a killer tornado. The dozen or so I'd encountered were weak, brief whirls over open country, except for a couple that did damage near Pampa last November. I was fine with that.
As we headed north, our sounding showed strong convective instability and more than sufficient deep-layer shear for supercells. Storm-relative helicity was lacking at our location near the Red River, but the sounding crew a county or two to the north reported a sickle-shaped hodograph supportive of strong tornadoes. Our target was a blip of reflectivity that had been floundering northeastward from the dryline near Duncan. We were thinking towers to our south on the opposite side of the river looked more robust. That was our own bias (though the Gainesville cell did go on to produce tornadoes in the Red River Valley). We just wanted to punch through to the south side of a maturing supercell. Instead, we rolled up I-35, wondering if the fuzzy anvil in the distance would survive or if we'd be going home empty-handed.
By the time we closed in on our next launch site, a hilltop east of Springer sprinkled with rain from a struggling cell just south, we realized the storm was going to do more than survive.
Successive distinct fingers of reflectivity appeared along the storm's southern flank and slid northward, congealing into an organized precipitation core. That's how the 2013 Moore storm evolved just after initiation. The similarities didn't stop there. As we turned north on Route 177 near Gene Autry, the other crew was watching a violent, highly visible cone tornado doing damage in Katie. Our next assignment came in: Mill Creek, back to our southeast and away from the storm. We had two choices to get there in time. We could double back to an obscure road of unknown quality that led directly east to Mill Creek. Or we could continue north into Sulphur, jog east on Hwy 7--maybe seeing the tornado--and drop south into Mill Creek on Hwy 1. Easy call. We caught a split-second glimpse of a high-contrast stovepipe tornado with a large debris cloud between stands of trees in the rolling, forested terrain south of Sulphur and flew into town.
Finally we emerged from Sulphur, where dozens of locals stood on street corners staring at the sky, onto a hill overlooking town. Several chasers and the other NSSL crew were there. We parked on the shoulder. I switched on my camera, jumped out, ran across the road, and got exactly one shot of the Katie tornado fully condensed in the distance.
The funnel lingered halfway to the ground for several minutes longer, but that was the end. We were just about to launch a balloon from that site when we realized the storm to the south was intensifying and sliding north toward our supercell, taking its developing mesocyclone directly over us. We had to dodge west and south away from the storm as it was clearly about to tornado again.
Our van stopped several miles south of Sulphur and, with a local man excitedly showing us the video he'd just shot, we attempted another launch. That sonde promptly got ingested by the massive storm (now producing a wedge tornado) and stopped transmitting in midlevels. Mill Creek became our target again, and we decided to get there the same way we'd tried to get there before. On the hill east of Sulphur, this time there was no chance of seeing the large tornado through the rain wrapping around the south side. The only view was to the tornado's east, and that was directly out of our way. We reluctantly turned south toward Mill Creek.
We were closing in on the town when a sunlit funnel or tornado suddenly appeared in the back side of a new supercell due east of us. Open views are nearly impossible to find in southeastern Oklahoma, so we settled for a field where we could see all but the lowest part of the funnel. We ran up to the fence and started taking photos. I wasn't sure if there wasn't a tornado warning yet or if Radarscope just hadn't shown it because of our spotty cell service, but I called NWS Norman. They seemed to know about it.
Then we launched near Mill Creek, sped eastward behind the southern storm, and put up a final sonde near Atoka as that storm dissipated.
After further review, the sunlit tornado wasn't the EF3 Connerville-Bromide tornado as we and the NWS had originally thought. This was a freakish circulation hanging off the west side of the cluster, between the Sulphur and Bromide storms, weak and barely detectable by radar. KFOR chopper video showed it on the ground toward the end of my series of photos, but it may or may not have been down at the beginning. The path was never surveyed.
I made three stupid storm reporting mistakes that I won't make again. First, I didn't even think to call it in until a couple minutes had elapsed. (As it turned out, this tornado didn't hit anything and the deadly one to the south was warned a couple minutes before my call, so it didn't make a difference, but it could have.) Second, I didn't nail down the location of the possible tornado, going along with NWS Norman's understandable but wrong assumption that it was on the next storm south. Third, I reported a tornado without confirming that it extended all the way to the ground, even though I've never seen a funnel get so close for so long without making it.
Later, we found out the EF4 Katie tornado had killed an elderly man toward the end of its path, which is hard to fathom because every local TV station was carrying a spectacular live stream and at least some were simulcasting on radio. The skinny little tornado we saw from miles away was the worst thing that ever happened to someone. Everyone in the weather community deals with that differently, but for now, I don't want that one hanging on the wall.
Wednesday, May 11
Wednesday wasn't a supercell day and we didn't operate, but a boundary draped across central Oklahoma kicked off some nocturnal storms that produced CG lightning in south Norman. The thunder from this one was an immediate crack.
Friday, May 13
Mini-MPEX passed on Friday, a marginal and somewhat unorthodox setup for the middle of May with a narrow window for high-based supercells ahead of a cold front. By midday, the HRRR locked onto a small target area at the far southwestern corner of Oklahoma. I made for Hollis, the last town before Texas on Route 62 out of Altus, and stopped on the north side of town just in time for the show. A few other chasers were scattered around the storm, but I saw none within a mile of my spot. That's rare for a kicking supercell in May on the Plains even with tornado probabilities near zero.
The storm was evolving from a small multicell cluster into an intense right-moving supercell as it came into view. At times the lightning in the forward flank had so many return strokes I could hit the camera button when I saw a flash and still capture the last few strokes.
As I headed south to get back ahead of the storm, which was taking a hard right toward the Red River, a thin laminar cloud appeared near the updraft base right before I lost sight of it in Hollis. Having just seen dust blasting south in outflow near that spot, I couldn't believe it was a tornado, but I cut back west to make sure. Nothing was there. A Warning Decision Training Branch scientist who saw it tweeted that it could've been a small rope, but nobody confirmed it and the official count for the day remains 0 tornadoes.
A new core had appeared almost directly over Hollis, and I raced east out of town in 50 dBZ big drops and what sounded like a couple small hailstones. For the next hour of escaping south into Texas, Verizon data was nonexistent. I wound up in Crowell before it magically reappeared. The supercell had faded after diving west of Hollis and was growing upscale. Showing a little shelfy structure, it came close enough for some sunset lightning shots that don't approach doing justice to the anvil crawlers overhead.
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