Three States of Strangeness

July 6, 2010 by · 1 Comment
Filed under: Summary 

Slapout OK and vicinity
13 Jun 10

SHORT: Observed entire lifespan of supercell from SE of Dumas TX to near Coldwater KS including at least one tornado near Slapout OK. Also observed floods, beautiful clouds and bizarre cross-country cycling experience.

LONG: It was just another ordinary, ho-hum chase day with a rain-wrapped tornado to our south moving east, uncanny resemblances between the Texas Panhandle and the Everglades, a house propped up by a Frigidaire, and an Austrian bicyclist riding across the prairie to the beat of techno-dance music from a German-speaking mobile DJ. Nothing special or different here…

The strongest combination of moisture, instability, lift and shear was forecast along a segment of the former cold front (now gone quasistationary) from SW KS to the eastern TX Panhandle, dependent strongly on how far S storms could backbuild in a manner sufficiently discrete to permit cyclic mesocyclogenesis and greater potential for tornado development. The outflow-reinforced boundary lay from just S of Dumas to near Coldwater at 15Z, and wasn’t going to go far except where effectively shunted E by localized convective outflow pools. The 12Z AMA sounding had a very weak cap atop anomalously large dew points, with clearing skies, so early initiation (perhaps even before noon) was virtually certain.

After leaving our lodging, the question of the day became apparent:

Riddle: What do Chuck, Keith, Texas Beef, and Natural Gas have in common?

Answer: All are names of roads crossing TX-152 within 10 miles E of Dumas.

Heading E from Dumas toward the boundary, we saw towers already arising along it to our SSE by 1130 CDT (1630Z) — these would evolve into the eventual Perryton-Slapout area supercell. We got on the warm side of the boundary between Borger-Pampa, as the same towers deepened and glaciated to our NW. The chase was on, and it was only noon! The visit for fuel and burritos at a Pampa Allsups had to be succinct, so we could head N toward the projected storm target of Perryton.

Once back up out of the Canadian Breaks and atop the Caprock again, we found flooded fields everywhere from the wet spring, led by the previous day’s egregiously profuse rains. These cowboys S of Farnsworth had to herd their herd onto an island in what clearly wasn’t supposed to be a lake. Evapotranspiration was a given on this day! Every time I got out of the car — curiously, except near the tornado — mosquitoes descended in voracious plumes, bloodsucking varmints eager to draw sustenance from anything warm-blooded, and especially from storm observers. I wondered how many “skeeters” ended up advected into supercell updrafts and entombed in the cores of hailstones.

Our towers grew into a fuzzy supercell with a CAPE-starved appearance near Farnsworth, slightly behind the boundary. It probably was surace-based, but not in the best air mass at the time, but did exhibit occasional but not particularly strong cloud-base rotation from broad lowerings (looking NW).

Meanwhile, strong cells were firing back down between Dumas-Pampa again, which we easily could intercept if this supercell fizzled. Instead, updrafts continued to develop in a break between our activity and the southern convection, merging in with the rear flank of the nearby storm. It all remained rather disorganized for about an hour, backbuilding at a rate nearly equivalent to its translation up the boundary, but with a slight eastward net component toward Perryton. We headed S of Perryton and down a submerged US-83 before the storm reached the area. Trucks in front demonstrated the shallowest path through the dead-still water, and that the road remained intact beneath; this is where driving a high-clearance 4×4 pickup came in handy. Such positioning would get us into position to intercept the southern storms if this activity couldn’t get better organized, or if it did, to head E and N to stay with the original convection, without dealing with the town and nearby flooding again.

Our adjacent storm developed a large, sculpted shelf cloud, made even more scenic by the foreground of the huge flood S of town that I called Lake Perryton. The south side of the storm sported a classic shelf, while the N side still wanted to be a supercell, with a tail cloud and occasional, weakly- to non-rotating lowerings. None of this, land or sky, looked much like the High Plains that it was!

Most of all, this did not look like a storm that soon would produce tornadoes. I was getting impatient with it, but instead of bailing S forthwith, I moved a few miles away and examined an abandoned house S of town with an eye back to the N, while stiff, cold outflow winds pressed down adjacent wheat. Good thing we didn’t give up on the storm, too, as it started to look better-organized and more like a supercell again (wide-angle looking N over Perryton). Its own outflow had carved out a swath of convection-free air upshear, while SE winds to its SE maintained good storm-relative inflow. Looking N from SW of Booker, a very well-defined clear slot and wall cloud appeared, and we knew we had to keep this storm in our sights.

About 10 minutes after this shot, taken looking NW from just E of Booker, the mesocyclone region became rain-wrapped from our perspective, then immediately spawned the long-lived supercell’s first tornado, visible mostly to observers who buried themselves deep into the immediate mesocyclone area on muddy backroads. By then we were repositioning E, then N, to stay ahead of the storm.

Recognizing this as an evolving, tornadic HP situation where one needs to get tucked into the notch NE of the mesocirculation to have the best shot at seeing a tube, we set up shop on US-412, in the OK Panhandle, between Elmwood and Slapout. That road provided a ready east escape, an option not available last time I was in a similar situation (with Rich T on 19 May). While watching the accelerating supercell approach, we spotted and photographed another abandoned house, this one strongly dependent on an antique, rusty refrigerator for its survival! When that porch overhang goes, the rest of the structure won’t take long to follow it down into the weeds.

We moved uphill and N 1/2-mile, watching the storm approach. A partly rain-wrapped, rotating, bowl-shaped lowering appeared to our SW (wide-angle view at 1611 CDT/2111 Z, left side) that looked like it meant serious business. We needed to get back down to US-412 then uphill again to the E, in case that turned tornadic (it probably was already), and in case we had to make the great escape. On the way down, we spotted VOF Doswell roaming the grounds of the very same house, but didn’t have time to stop for idle chitchat.

Just after we climbed E and parked beside 412, a brief funnel and some diffuse multivortex filaments appeared under the lowering at 1616 CDT, just before I could shoot. Although the interceding, non-condensational stage lasted a few minutes afterward, I believe this was one continuous, tornadic circulation with the next stage, which manifest as a bulbous, tapering cone, then a well-defined and rain-wrapped cone with filamentous elements whirling beneath. By 1620 CDT the visible tornado became elongated, tapered, curved, narrower in appearance (normal and wide-angle views, by which time the tornado was to our S, moving E). We lost sight of the increasingly ill-defined tornado in wrapping rain to our SSE at 1622, by which time the onset of precip overhead (in the inner-notch region) compelled us to bail E on 412.

Now look at any of the wide-angle tornado shots and imagine the tornado away. What do you see? Otherwise, it looks like an outflow-dominant, rather junky storm organization with a big gust front and some pretty turquoise coloring on its N side. I’ve seen perhaps hundreds of similar-looking storms with no tornado wrapped in there behind the ragged shelf cloud; but in this case, there it was. And that’s all the supercell had left in a tornadic sense.

From then on, the storm’s successive mesocyclonic occlusions ingested excessive amounts of rain and outflow for tornadogenesis. We weren’t sure of this yet, of course; so we zigzagged N and E toward Laverne, meeting Howie along the way (action shot) and nearly getting struck by a staccato CG — the first among a sudden barrage that erupted immediately NE of the mesocyclone(s) in an area heretofore bereft of such a deadly menace. The bolt in question, which was so close I couldn’t tell the direction it hit, gave off an audible “snap” a split second before the simultaneous flash and slicing report of thunder. That momentarily disturbing sequence sent me leaping back into the vehicle glad to be alive and unharmed! I wonder if the snapping noise was the audible effect of a ground-up discharge from some close-by object that preceded the actual return stroke by a fraction of a second.

Shortly after Howie left and before encountering the CG, this shot revealed a dark, HP “stormzilla”. Notice the stubby, translucently rain-wrapped funnel at lower left, looking WSW from N of Slapout (heavily-enhanced crop-n-zoom). That highly suspicious protuberance emerged at 1640 CDT from some heavier precip. It also resided beneath a small, obviously rotating tail/collar feature rolling northward along the E face of the storm, toward a broader but weaker mesocirculation in the dark area to its right (N). We cannot be sure whether or not this was a brief tornado.

Those were the last shots we took from the storm’s inflow region. It started to gust out, merge with adjoining convection, and evolve a bowing feature as it headed for the area between Laverne and Coldwater KS, hot on our tail. With a central-northern plains target to reach in a couple of days, our minds turned to the potential photo ops on the backside of the complex, so we rushed up to Coldwater and let the northern part of the storm roll over us with likely-severe gusts and a barrage of subsevere hail. After the requisite inland-hurricane experience, we cruised WNW toward DDC for lodging and supper.

Along the way, we noticed a peculiar and wonderful combination of visual effects: underneath the MCS’ trailing anvil (not seen in the photo), laminarity along the top of the boundary layer, marked by a hazy delineation, and backdropped by pastel light from and through convective towers. Seldom have I witnessed such a combination, soothing in its beauty. Then things got [i]really strange.

As we stopped to watch and shoot that scene, a few miles SE of Ford KS, a distinctive male voice could be heard, slowly rising in volume. Elke asked me what I said; I hadn’t been talking. In a few more seconds, the source became apparent: a car slowly driving southeastbound toward us, on the shoulder of US-400, lights on, following a cyclist. The cyclist, dressed in skin-tight uniform covered with colorful sponsorship logos, rolled on past, followed closely by a car even more festooned in corporate logos. These, however, mostly were unrecognized ads, and the voice booming from the car’s loudspeakers was German! It was hard for Elke (a native German-speaker) to make out what he was saying, however, beneath the pounding beat of Euro-tech dance music also booming from the speakers. It was a rolling DJ, following a European cyclist across the Kansas prairie into the backside of an MCS!

We stopped in Ford, and right there at the convenience store was an RV parked, with many of the same logos as the weird cyclist/car tandem. Overcome by curiosity, Elke and I asked them (well, she did, since she spoke their language). The cyclist was from Austria — indeed, from the same general area as Salzburg, where Elke was born. He was riding across the USA from San Diego, and was only about 8 days into the trip. This means he had ridden well over 100 miles a day, including over the Mojave Desert and the mountains of southern Colorado. You have to respect that! They exchanged pleasantries, but seemed disappointed when she had to answer negatively to their question about where a good dinner could be found in town. For that, for them, it was either head back to Dodge or go all the way to Pratt…

After our own good dinner (a celebratory steak) in DDC, we parked on a hilltop W of town for a short-lived but gorgeous display of mammatus in the sunset light. The clouds glowed somewhere between champagne, iced tea and bronze on the spectrum of hues, and made for a marvelous conclusion to one of the more bizarre but enjoyable storm-intercept days in a long time.

Clam’s Foot Surfer

July 1, 2010 by · Comments Off on Clam’s Foot Surfer
Filed under: Summary 

Dumas TX and vicinity
12 Jun 10

SHORT: Observed outflow-dominant line E of Dumas, elevated stage of supercell SW of Dumas that hailed over us at dinner.

LONG:
Elke and I began the day with a cold breakfast at our Burlington motel, joined by Chuck and Teresa Robertson, then Matt Crowther and Vince Miller, all of whom also had intercepted the Limon-area supercells the day before. The cold front was surging farther S, faster than forecast the previous day, so we all had to get out of town soon and jaunt down south to the Panhandles. For Chuck and his lovely bride, who live in the northeastern TX Panhandle, it would be a return home, with storms along the way.

After a couple of hours on the road, we stopped to pick up some provisions at the Wal-Mart in Lamar CO. On the way to the rear latrine, I spotted a familiar human form — there was Vince, picking out a shirt in the clothing section! What are the odds? A short chat with him and Matt outside, and we all were back on the road again. We wouldn’t see either of them the remainder of the day. Still, in storm observing, such are the unplanned, chance encounters one can have with familiar old friends and acquaintances.

By the time we got to Boise City OK, storms already were firing along the cold front to our S and SE in the TX Panhandle, with big towers erupting beyond the cool, foggy haze. The most robust of those went through a briefly tornadic supercell phase well before we could get to it, then turned into a large HP mess. We thought about “rounding the corner” on it E of Dumas, but by the time we committed to that plan and got near it, the entire complex had degenerated into this rather amorphous, outflow-spewing mess, all while dumping nearly a foot of rain from train-echoes near Morse.

Another fun serendipity of storm observing is being in the same place twice, hundreds of miles from home, on different days and different storms, in the same season. Such was the case with the last photo, which I took on FM-1060 while less than a hundred yards from where I shot the mesocyclonic merry-go-round E of Dumas the previous month (see You Decide, 18 May 10). We retraced steps from that amazing May day eastward through Stinnett and north a few miles, but without such intense atmospheric results.

While shooting time lapses N of Stinnett, David Hoadley pulled up and chatted with us for awhile in the cool outflow. It’s always a pleasure to see Dave again, as I seem to do about once a season at some random rural pull-off near a storm. Some new cells were trying to fire south of the outflow boundary and W-NW of AMA, so Dave and I agreed that was the only remaining viable target, and parted ways, independently heading the same general direction. Along the way back to Dumas, Elke and I stopped to shoot a couple of peculiar, fascinatingly illuminated and somewhat convective scud formations (first and second).

One longer-lived cell had crossed over the arching outflow boundary SW of Dumas but remained intense on radar, so after grabbing a motel room there, we drove a couple of miles S of town to take an unobstructed look. We still were in cold NE outflow from the massive complex to our NE, and this storm was obviously elevated at the time, exhibiting laminar formations and riding atop an elongated, clam’s-foot cloud formation (wide-angle view looking WSW) as the chill breeze at our backs strengthened further. Ribbed texturing to the main low-cloud band, glowing in twice-reflected, late-afternoon light, formed an uncommon and striking visual backdrop for the wind farm SW of town.

Thinking somewhat erroneously that the storm would remain elevated, we ate dinner in Dumas as it rolled over us, profusely peppering the restaurant windows with a protracted blast of hail near an inch in diameter. I was tempted to run out and grab some hailstones as ice for my drink, though the Moore County Health Department might not have approved of this item on the menu. It turns out that the supercell backbuilt and right-moved, once again getting close to the eastern segment of the curving boundary, and becoming surface-based again to our E, after it left town. We finished supper and headed a few miles SW of Dumas hoping for sunset photography, but with all the various clouds in the way, all we could salvage was some twilight pastels over ripened wheat.

We slept well that night, knowing that the next days’ target would be in the Panhandle also, but not knowing that we would see both a pretty tornado-producing supercell and the largest amount of standing water we’ve ever witnessed on a High Plains storm intercept.

Panhandle Unchase

June 10, 2010 by · Comments Off on Panhandle Unchase
Filed under: Summary 

Channing/Groom TX, 25 May 10

SHORT: Observed supercell get munched by outflow-dominant multicell complex NW of Amarillo. Pretty sunset.

LONG:
This wasn’t specifically intended to be a chase day; but if we happened to see a decent storm along the way, that was acceptable! We had a truck bed full of cargo from Elke’s late mom that we were bringing home from DEN-OUN. Even though most of it was well-covered by plastic, getting in a bunch of rain and especially hail was not a palatable option. Therefore, even though the most dense concentration of convection promised to be along the Kansas segment of the dryline, where tornadic storms did occur, we opted to use the southern route through the Panhandles in hopes of more discrete activity.

We could see the first towers erupting along the dryline, early in the afternoon and to the distant E-ESE, while still on I-25 in southern Colorado. After turning ESE on US-87, a series of big towers grew into storms to our ENE and NE, including some of the Kansas activity that provided the joy of rich and abundant data to V.O.R.T.EX.-2 scientists. Near Des Moines (the New Mexico town, that is), we saw a classical, atom-bomb style of thunderhead eruption in the western Texas Panhandle, off to our SE (here photographed beyond one of the area’s numerous, inactive cinder cones). Given the favorable shear and discrete nature of this storm, its destiny as a supercell was assured, and our destiny was to intercept it — preferably avoiding most of the precip.

It took us a long time to get around to the E side of the slow-moving storm, even via the fairly direct CAO-DHT-Hartley route on US-87. As we approached DHT, radar imagery indicated that a left-split off of some storms N of Clovis was growing into a large, northward-moving multicell cluster — headed directly for our intensifying supercell! Just our stinkin’ luck! Tracking our course and that of the raging multicell cluster from hell, it was obvious the solitary supercell with so much potential would be snuffed out like a match in a fire hose, not long after we got in viewing position.

Our viewing position turned out to be virtually the same spot N of Channing from which Rich T and I first observed the tornadic Dumas-Stinnett supercell from 18 May. Unfortunately, this textured and colorful little storm was about to be absolutely destroyed by the onrushing wall of outflow and convection from its S. We had about 15 minutes of viewing as that happened, then headed to AMA.

There was too little daylight left to attempt to intercept Jeff Passner’s tornadic storm near Dimmit, so we stopped in AMA for dinner, drove E, photographed the Leaning Water Tower of Groom in some nicely reddening sunset light, then drove on home in the dark of night. So, in effect, we were able to observe the shortest-lived and most decidedly nontornadic supercell in between all the longer-lived, tornadic ones.

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