Storm Structure and Lightning Extravaganza in Western Oklahoma

April 13, 2008 by
Filed under: Uncategorized 

Corn to Rocky to Gotebo to Anadarko OK,
30 Mar 2008

My storm observing comrades on this day were Melissa Hurlbut and Jason Levit. A protracted period of target indecision on my part continued well into the afternoon hours, even after Jason arrived at my place around 3 p.m. Two interesting areas presented themselves in the various mesoanalytic clues:

1. The western part of north-central OK, Woodward-Enid, near a cold front/warm front intersection and near and dear to my longstanding triple-point bias. I liked the shear up there, both in low levels and through aq deep layer, but surface-based buoyancy would be limited, and the warm frontal zone had a NNW-SSE alignment that was too perpendicular to the prospective mean flow and supercell motion vectors for my tastes.

2. A more nebulous but also more unstable zone near the dryline, over SW Oklahoma, where precise foci for forcing in the low levels would be rather diffuse, but where any storms that could form would have hours of room to roam in rotational enrapturement.

After picking up Melissa, we leaned toward the southwestern option, but decided to head out I-40 (via the Newcastle-Mustang bypass) in case some profound clue emerged in the interim that would change our minds. Jason hadn’t been out on a storm intercept mission since 2004; and this would be Melissa’s first since moving to Oklahoma (she previously had chased on Paul Sirvatka’s 2007 COD expedition to Old Mexico, among other trips).

A profound sense of responsibility silently inundated me: the need — truly, the requirement — to rush these faultless sufferers of supercellular deprivation straight to the smorgasbord of atmospheric violence, without further ado.

Mission accomplished, with a rare and stunning ease…

Towering Cu liberally festooned the warm frontal zone between Newcastle, Mustang and I-40, an encouraging sign. We cruised W along I-40 at a brisk pace, further encouraged by an increasingly dense and deep clump of towering Cu that Jason noted on I-Phone satellite imagery, just ahead of the dryline. As we approached Weatherford, we could see the agitated area to our SW-WSW, including a turkey tower and one nascent Cb. Turning S out of Weatherford toward Corn, the towers rocketed skyward and glaciated, forming a skinny but robust storm just to our WSW, seemingly on cue, as if the whole process had awaited our arrival. The appetizer was served, and we dined with gusto. We parked about 3 E Corn for over half an hour with a fine view of this storm, watching an absolutely classical, textbook storm splitting process to our W. The left mover peeled off to its NNE and our NW, while the right mover (christened “Jorge” by Melissa, in fine hurricane naming tradition) headed ENE toward us.

We jogged S a few miles to get out of anvil rain, to watch our western storm “Jorge” for at least a little while, and to get a better view of another growing Cb farther SW (wide angle view of both storms). Jorge was spinning cyclonically, but without much vigor, and exhibited a rather small, high base. Meanwhile, the distant base of the newer storm grew large and began to develop a pronounced wall cloud with suspicious lowerings, whereupon Melissa decided it was worth a name and asked me to take the honors. “Fabio” it was. Comparing the two storms, we decided the southern one had a better future, so we zigzagged past the S side of Jorge and headed toward Cordell and an encounter with Fabio. As we drove past Jorge for the last time, E of Cordell, it grew a larger but still high base, while Fabio obviously and rapidly had become a cyclic, right-moving anchor supercell — the main course on our convective feast.

Intercepting Fabio in this fantastic and traditional storm chase country, with such outstanding openness, road options and visibility, was a piece of cake. Steady, manageable storm motions and skeletal structure certainly helped! We cruised S out of Cordell on US-183 through Rocky, driving through a little anvil rain and melted/melting hail, then wheeled into a viewing spot just S of Rocky. Storm structure looked great — a striated, squat cylinder just to our W with a pronounced hail shaft streaming off the vault region to the NW. The upper reaches of the hail shaft streamed high aloft, nearly overhead, arching slightly north, and the updraft’s spinning stack of tires plodded along right toward us. We knew we couldn’t linger for long; indeed, a smattering of .75-.9 inch hail and the promise of even larger ice balls soon sent us along our way. By this time, Jason and Melissa already were exquisitely pleased with the offerings from the smorgasbord, but the feast was far from finished.

We turned E on OK-9 and stopped a couple of times between HBR and Gotebo so we could observe this increasingly spectacular supercell to our WNW, including a marvelous, sculpted storm and sunset scene and postcrepuscular rays behind us. In the fading twilight, Fabio whirled onward across western Oklahoma, at times looking something like a pair of horizontal flywheels with intermittent wall clouds and RFD cuts beneath.

I wasn’t concerned about tornado development before dark given the high base and lack of visibly tight low level rotation, but had increasing confidence Fabio would survive after dark and have a chance to get really mean once it latched onto the low level jet and drew in an air mass characterized by increases in both relative humidity and mixing ratio. Meanwhile, we had seen occasional chase vehicles here and there, but the lack of more dense crowds was a pleasant surprise. I guess the profusion of paved road options, and of unpaved section roads for viewing away from the highway, helped to disperse the storm chase hordes enough that they were hardly noticeable.

Fabio kept swirling on into the evening, and we kept the storm abeam to port through Gotebo and along the first few miles of the bypass road N-NE of town (the same road alternative that Rich, Jim and I found 28 days earlier) parallel to the closed section of Highway 9. We stopped for awhile to let Fabio move to the NE, where lightning could silhouette its features. Meanwhile, we started to make out a storm to the NW that also was developing supercell characteristics, both visually and on radar imagery that Jason was downloading into his phone. This time the naming rights would belong to Jason — Rico it was.

The new storm appeared to attach itself to Fabio’s rear flank outflow (a very disgusting and repulsive thing if these were people and not storms), and moved very deviantly rightward for awhile toward the SE until it was lined up alomst E-W with Fabio. These two storms would move E in tandem for an hour or so, then interact in a Fujiwara dance, with Fabio ejecting quickly N then NW around the forward flank of Rico. Although tornado warnings and one report came in from about 15 miles to our N, we decided not to risk plunging into the murk and perhaps being cut off along state roads 152 or 37 eastbound.

Instead, we pulled into a high spot E of Anadarko that I had used before, with a commanding view of the amazing electrical show now underway to our N. So-called “anvil zits” — zippy little filaments that zap hither and yon across supercells’ inner anvils — lit up the sky with astonishing frequency, at least one per second. I’ve seen many supercells at night, some of which left me spellbound at their electrical prowess. While a very few have matched the dazzling profusion and frequency of the middle-upper level discharges that Rico and Fabio were spewing in tandem, none have exceeded them, ever in my experience. Capturing them in photographs was laughably easy! See this photo or this one or this one, all looking NE, or this shot looking NNW? I took dozens more similar to those; and I kid you not, I possibly could have had hundreds. This was easier than shooting fish in a barrel, despite the strong and very gusty inflow winds that made me press my weight downward against the tripod to steady it, and yet, still find wiggles on the lights in several of the longer (10-11 sec) exposures.

After filling up my memory card, then culling out a couple dozen “lesser” but still good lightning shots, then filling it up once again, I noticed we all were getting tired, and didn’t bother to swap out cards. We enjoyed the lightning extravaganza for its own sake for a few more minutes, then called it a day and headed the short distance back to Norman, content with one of the best nontornadic storm intercepts to grace these parts in a long time.

Great company, great storms…ain’t that what makes a great chase? That it was.


Comments are closed.