Supercell South of Woodward

May 13, 2010 by · Comments Off on Supercell South of Woodward
Filed under: Summary 

Briefly Tornadic (11 May 10)

SHORT: Intercepted brief storm attempt W of Cordell and briefly tornadic supercell S of Woodward.

LONG: Ryan, Corey and I trekked out again on the “day after the day” with hopes of finding a tornadic supercell somewhere near the remnant frontal zone, which was retreating north as a warm front across western OK, or the dryline not far to its S. Deep-layer shear would be more than sufficient to support this potential anywhere along or S of the warm front, and the frontal zone itself promised backed flow, maximized boundary layer vorticity and enhanced low-level SRH for any storm that could form along it, or the nearby dryline and interact with the front. A stout cap and more nebulous low-level forcing yielded considerable uncertainty for this day, which was reflected in the justifiably low unconditional tornado probabilities in early outlooks. Compared to the frantic racetrack nature of storms the day before, one advantage would be cell motions far more manageably interceptable.

We waited a long time at Clinton, watching the warm front pass to our N and gradually deepening Cu in the warm sector. With little of note happening along the warm front or its intersection with the dryline, we took a look at a short-lived Cb that erupted not far away, S of I-40 and W of Cordell. Disturbingly skinny, the updraft seemed to suffer from too much dry entrainment, and left behind an orphan anvil. We only messed with this briefly before hastening back up to the warm front to await any chance of diurnal initiation.

We passed the warm front near Leedey and sat at an overlook near Camargo, one apparently prized by the research community for its utility as well! Shortly afterward, a V.O.R.T.EX.-2 radar truck appeared, their occupants wishing to use our parking space to set up surveillance for the nascent storms bubbling along the front to our W. We were pleased to oblige, and I had some enjoyable conversation with a few of its occupants from NSSL (Kim Elmore driving, Conrad Zeigler and Gabe Garfield onboard).

We had sustained, deep-convective initiation, at long last…8 o’clock magic! The more distant young anvil in the previous shot became the easternmost of a storm pair in short order, and was targeted by the field project. Meanwhile, we instead targeted the more vigorous young storm to its immediate W, blasting W on US-60 from Vici and ignoring the crappy-looking eastern storm. Even though we got on it early in its lifespan, we still were almost too late! The western storm went from barely having a radar signature to a strong mesocyclonic couplet in just a few volume scans. While going rollercoaster-like through hills W of Vici, we began to see the distant base(s) of that more distant storm, as it interacted with the vorticity-laden environment of the warm-frontal zone.

The more distant of its two main bases — already deeply occluded, suddenly spawned a brief, fuzzy, but obvious condensation funnel that fleetingly made ground contact off to our distant WNW. The tornado was at 2025 CDT in SW Woodward County, N of Harmon. We were driving westward in a remote, somewhat hilly area with no AT&T service, about 7-8 miles W of Vici (pronounced Vy-sigh) at the time, and the tornado was gone before we could find a place to pull over and shoot, so…no photos. However, scanning StormTrack, I found one photo of it from C.D. Collura…
…which definitely was our tornado.

I did call it to the WFO in a few minutes later when we were in a window of some cell coverage. Unfortunately I had trouble giving a specific tornado location because my road atlas was falling apart in my hands as I was trying to call and while we were driving, with pages falling everywhere! By then of course the storm had cycled another (non-tornadic) occlusion, and had a cold, fuzzy, increasingly elevated look (also mentioned on the phone). That “cheeznado” was the storm’s first, last and only hurrah in that regard — truly, a needle in the haystack that shockingly few of the numerous storm observers chasers in the area appear to have witnessed. It would have been easy to miss. By the time we found a safe and closer pull-off, the old occlusion was decaying further (left, in this photo, looking NW-N), while the new mesocyclone (at right) never could tighten up enough, and had a colder, more stable appearance.

By the time we got back E to Vici and N again toward Woodward, we began to see some great structure in fading twilight, but most of the colors that other chasers (who had been farther E) photographed so well were about gone. We ate a late Arby’s dinner in Woodward with two Environment Canada meteorologists (Neil Taylor and Dave Sills) and Matt Crowther, then headed back on the long drive home.