Strike Three (Time for New Game)

August 5, 2013 by · Comments Off on Strike Three (Time for New Game)
Filed under: Summary 

Lindsay and Elmore City OK, St. Jo TX
20 May 13

SHORT: Strike 3, batter out for this system. Intercepted 3 supercells in 3 tornado warnings and 2 states, saw no tornadoes: 1) Lindsay OK, 2) between DUC-PVJ, 3) near St. Jo TX.

LONG:

Setting up “the day after the day after the day before the day”
Somehow, on consecutive Kansas/Oklahoma tornado days, we had come up empty-handed in that regard–and worse, with very few decent photos or positively memorable experiences to show for it, despite multiple storms intercepted. This third chance, a cold front was moving very slowly SE across central OK, into an air mass characterized by upper 60s to low 70s F surface dew points, and strong surface heating. Many long-time, seasoned storm observers, in their pre-chase forecast musings, targeted the cold-front/dryline triple point area, forecast to be near FSI by late afternoon. Rich T and I wanted to hang a little closer (CHK area) for starters, but as it turns out, not even that was “close” enough.

My last forecast offering before hitting the road summed up the pre-chase situation fairly well:

    In some ways, this is a messier, more difficult chase-forecasting scenario than previous two days, and we still somehow avoided all the tornadoes on them. What does today have in store?

    Could be an early-initiation scenario (relative to previous days), especially on the “northern” end of the regime from the CHK-OKC area NEward, given positioning of the upstream shortwave trough, high CAPE, rich low-level moisture and likelihood of CINH eroding fairly quickly in SSW-ward zippering fashion. This looks like one of those patterns that support fairly quick SWward backbuilding after initial mode of relatively discrete storms. Two big questions to answer today:

    1. How long will discrete mode last?
    2. Will storms go too early and get messy while the warm-sector flow still is somewhat veered, and before low-level SRH picks up later in the afternoon?

Rich and I were rather worn out from the two prior days, but decided to head out anyway, given that the threat was within a couple hours’ drive of home. By the time we left, shortly after 1 p.m., deep towers already were building along the cold front W and SW of the OKC area, and along the dryline farther SW.

What was and could have been
Migrating our way SW, we noticed two main areas of development–a multicellular splotch near FSI (later to evolve into the DUC-PVJ supercell) and a more discrete, fast-growing echo SSE of CHK, headed toward PRC. The latter was closer, moving into a high-CAPE, moderate-shear environment, and more isolated, so we migrated that way for starters. A nice vantage from just E of Lindsay offered this early view of the young storm to our WSW, still small and beginning to fall under the anvil shadow of the FSI-DUC cluster (the latter’s anvil being visible at distant left).

Had the Moore storm formed either first, or a little later (with more time to get there), we might have targeted it instead. However, it developed to our NNW near Blanchard, with a rather ragged early look for such a big-CAPE day, as seen through the anvil precip of the Lindsay storm. Being in the immediate inflow of the latter, which still held some promise of growing and maturing, we held position.

Questions about our storm’s current and future integrity arose with the dramatic sharpening of the appearance of the future Moore storm, the narrow updraft of the Lindsay supercell as it moved nearby to our NW, and the rain falling into the latter’s inflow from the anvil of the DUC cluster.

Before long, the Lindsay supercell weakened dramatically, leaving us sitting there stormless with this decision: zigzag back NNE to I-35 and try to catch the northern storm, now tornado-warned and sporting a hook as it moved toward western Moore, or head S on a more straightforward path to ahead of the consolidating and closer DUC convection, by now also sporting a radar-indicated mesocyclone and moving NE (much faster approach). Chasing in the metro area also was considered a negative; so we turned S.

Soon after doing so, we heard a frantic TV simulcast over the radio describing a growing and potentially violent tornado moving into Moore. This was terrible news on multiple fronts. Moore had been devastated multiple times in the past 15 years, and this was the last thing they should have to deal with. Secondarily, we were getting the vibe that, for the third day in a row, it just wasn’t our day to see a tornado (despite not reaching the DUC storm yet).

We still had time to do a quick turn-around and maybe catch the Moore storm after it crossed I-35; but stern-chasing a destructive event through the suburbs seemed rather unwise. By contrast, Elke, who had stayed home and was watching the event unfold on TV, was able to get a safe, in-person peek of the last few minutes of the Moore tornado simply by driving a few miles N and finding a hillside vantage (E. Franklin Rd E of 36th Ave). Some trees and terrain were in the way, but she watched as the Moore tornado (by then well E of I-35) appeared to her NW, narrowed, then roped out in wild, loopy fashion.

Meanwhile, an hour to the south, we simply had to digest the fact that we were missing what sounded like the worst central OK tornado event since 3 May 99, while also hearing a report of a brief tornado from the DUC storm that we hadn’t reached yet!

Post-tornadic DUC-PVJ supercell
Heading W out of Elmore City, we caught the former Duncan-area supercell W of Foster. Finding reasonable vantages was difficult amidst the shoulder-deprived roads, hills, trees, an abundance of both real and imitation storm chasers taking up the best pullouts, and storm structure that looked very wet and messy via glimpses through the obstructions. What was left of the main mesocyclone got wrapped in rain and lost its identity NW of Foster, as very heavy showers flooded the main supercell’s inflow region with their own stabilizing effluent. A newer meso seemed to get undercut as it crossed the road nearby, and as we experienced cold RFD outflow to its immediate SE.

Nonetheless, the storm tried, amidst all the convective-scale slop, to maintain some supercellular identity as it headed ENE between Elmore City and PVJ. This view, looking NW, was about its most robust appearance, with moderate visual rotation and a concurrent reflectivity hook on radar, before it crossed I-35 just N PVJ. After short deliberation in town, we let the gradually shrinking storm go, and plunged S on I-35 to intercept whatever would remain of a big North TX supercell located SE of SPS. It was either that or give up and crawl home in shame. Not being easy quitters, we decided to make a go of it.

Takin’ the Tejas plunge and back
Radar showed the Texas storm right-moving toward Muenster, so getting safely ahead of it would be easy at legal Interstate speeds. First, however, we had to reach to a spot just S of the Arbuckles before the front wall of a formerly discrete supercell–by now a messy storm tangled up with a large load of other convection, and dominated by a deeply rain-wrapped/forward-flank circulation. We beat that electrically active mélange of amorphous slop by just a few miles (structure so fuzzy it wasn’t worth a photo stop), then proceeded across the Red River. A left-mover we had been monitoring SSE of the storm was closing in fast, leaving us with (at best) a narrow window of potential before mutually assured convective disruption.

Turning W on US-82 aimed us toward a dramatically darkening and increasingly lightning-splashed western sky. After we left Gainesville, the former fuzzy mess that we had ignored got tornado-warned NE of ADM. That’s right–kick us while we’re down!

Between St. Jo and Nocona, we found a temporarily good place to park, as the supercell–by now an HP stormzilla into which the large left-mover already was ramming with great force–closed in. While waiting, we encountered Matt Crowther and Vince Miller, and had a short but nice chat with them.

When the approaching half of the sky looks like this, and then several minutes later, like this (notice the long line of fleeing vehicles), it’s not a wise idea to stick around sipping frosty brews and smoking Cuban cigars from the comfort of lawn chairs. Having no such suds, smokes or seats anyway (just shamefully seldom-used cameras), we high-tailed it E back to Gainesville. Meanwhile, ransacked by all the cell mergers, collisions and outflow, the formerly imposing storm became a gusty heap of rain and lightning. Whataburger time…

We ate, let the heaviest part of the cores slide by to our N, then shot the convective gap northward before some heavy, training and elevated storms reached the Marietta/ADM area. Some beautifully colored sky, just before and after sunset, greeted us near Springer. That offered but a small modicum of cool relief on part of what felt like a substantially large chase burn. By the time we rolled back N on I-35, in despair over the disaster in Moore, and with Rich’s chase vacation having ended on three straight swing-n-miss days, we were quite ready to carry out the sentiment expressed by the following quote from 2006…after all, our chances of seeing Sasquatch seemed greater at that point.

    “Let’s forget this tornado chasing and go look for Bigfoot.”

There still was some vacation time left for me, however. Soon, I would desire (and embark upon) some much-welcomed and soothingly corrective “High Plains Therapy”.

Easter Sunday Supercell along US-82

April 13, 2009 by · Comments Off on Easter Sunday Supercell along US-82
Filed under: Summary 

Wichita Falls to Gainesville TX
12 Apr 9

SHORT: Supercell intercepted from near SPS to Gainesville, severe hail measured, large evolutionary variations in storm character along with great structure witnessed and photographed.

LONG: I had been watching the next “cold-core” chase potential rather casually for a few days in advance, aware that it could be close at hand, but distracted by assorted diversions of life. Nonetheless, I had mentioned to Elke and my two teen-age kids that there could be some chase potential Sunday, and to be ready to head out with me, if desired. The kids do love to chase, and don’t get to do it much thanks to school, so they were hoping.

After Easter services, we went home, and I liked the narrow slot of clearing and heating that was occurring in VIS imagery, with only upper 50s to low 60s F surface temps needed to uncap the boundary layer, given such cold air and steep lapse rates aloft. Something loosely resembling an occluded front laid out near the Red River, arching NW across SW OK and into the SE part of the TX panhandle. Near and NE of that boundary, winds were backed; and to its W, surface winds were veered with very little SRH for most reasonable storm motions. A storm that formed in the clear slot would have to interact with that boundary to get happy and spin for a good while. We just needed a storm, and a favorable boundary-relative storm motion. Dew point depressions where there was decent heating and instability seemed a tad high for my taste; but when you’re off, it’s spring, and there’s a shot at a supercell nearby, then…go!

The storms probably wouldn’t be tornadic, but one could get lucky. At worst, with no meaningful storms, this would be a country Sunday drive and some family time, probably with some time hanging out in the Wichita Mountains. Given the very conditional nature of the event, to allow more room in the car, and because she had some work to do, Elke stayed home. I think she mildly regretted doing so after we (David, Donna and I) got back with some great chase stories and photos. 😉

We didn’t get to the Wichitas.

Breaking out of the grunge, mist and slop just N of FSI, we exited for gas and I dialed up satellite and radar on my I-Phone. Meanwhile, David and Donna helped a handicapped old man who was parked near us look for his lost car keys. His keys were found, and so was a necklace of reflectivity pearls on the radar scope, from near CDS ESE across the SPS area. While the cells SW of FDR would be closer and more convenient to intercept, the tail-end storm developing WSW of SPS would
1. Remain in the most unstable boundary layer air mass the longest,
2. Have unimpeded inflow, at least for awhile,
3. Remain closest to the larger gradient flows and stronger deep-layer shear vectors aloft (farther from the center of the vortex aloft), and
4. Have a great chance to interact with the boundary after maturity.

Such meteorological reasoning made the decision easy. We zoomed down I-44 through SPS, getting a visual on Tail-end Charlie by the time we got clear of the FSI area. From then on, I never needed the I-Phone radar app, but it helped in the early strategic decision, and I used it occasionally out of curiosity during stops, as time permitted.

While still in OK, the storm was visible from a long distance (>40 miles), with a high but robust cloud base, intermittent wall cloud-like lowerings next to or behind the translucent precip core, and a sharp anvil (sorry, no photos…driving on an interstate). We got through the SPS area and set up along FM-1954, 2 SE of Lakeside City, as the high-based storm (initially to our W over US-82) became somewhat more elongated, with a verticaly tilted base. This was the first of a few occasions when I thought the storm was losing organization, and that dinner might be imminent!

As the storm impinged upon our position, I headed E to the spillway area of Lake Arrowhead to watch it approach once more. The scene was beautiful, but the storm was very high based, with a skinny, shelf cloud-like appearance to the updraft region. We collected some dead mesquite (for my grill at home) and admired a long-abandoned trailer and boat (decal dated 1966!) while letting the storm go by to our N, across the SPS area and eastward toward Henrietta. As it was passing to our NNE, the E part of that elongated base broadened and thickened some, followed soon thereafter by a more HP supercell appearance. The storm did a small but intense core dump, complete with classical downburst rain foot, to our NE near Henrietta.

I followed the storm toward Henrietta, and after seeing the core get more translucent (looking ENE from 6 WSW of town), decided to penetrate it and maybe get some interesting late-day lighting under the other side of the base and shelf cloud. I asked the kids if they wanted to get into some hail (they have before, several times) and told them we might find some going through the “thin” core, since it was so cold aloft. Did we ever…

As we drove E into the precip (on US-82) it seemed to thicken considerably, as if another core dump was taking place. I expected lots of small hail, and maybe some technical-severe cheese, but this hail was nearly significant. A large amount of hailstones around an inch diameter pounded us as I pulled over right alongside the Montague County line sign, at its border with Clay County. David reached out and brought in several of the biggest stones, lumpy oblate spheroids that uniformly measured 1-3/8 inch on their long axes. I called this report in to WFO OUN, but it didn’t show up in the rough logs. [Estimates of larger sized hail came from nearby.]

The hail continued for a few miles past Ringgold and thinned near Belcherville…and man, did it ever get dark in that core for something that looked so benign when we were west of it. After we popped out the other side and pulled over, 3 W of Nocona, we saw why. Once again, it had reorganized, this time into a MUN (mean, ugly, nasty) monster, looking much like the prototypical north Texas HP Stormzilla, with a wall of scud roaring up the leading edge of the the outflow surge. And we had just gotten out before it became really intense. Whew!

Cows, placidly oblivious to the impending experience of hail bouncing off their skulls, grazed in the field as the supercell clawed onward toward us. We cruised E through Nocona, finally seeing a couple of chase vehicles (one belonging to a chaser that the kids and I know, Scott Peake, with whom we briefly spoke). I was mildly but pleasantly surprised at how few chasers were out there, especially considering I was on a major U.S. highway just ahead of what had become the only supercell in the region.

The road took a right turn more to the SE, and so did the storm — right into a hilly and more forested area of the Western Crosstimbers habitat, where good views would be hard to find. Fortunately, I stumbled upon a great westerly vantage about 3 NW of Saint Jo, at a roadside picnic area set atop a hill. We watched the storm from there for awhile (wide angle view). It actually shed some of its densely HP visual characteristics, acquiring more sculpted structure aloft and maintaining a convergent, slowly rotating wall cloud under the main updraft area. At no point did I see any cloud base accelerations that suggested imminent tornadogenesis, despite having a good view through zoom lenses; nonetheless, we observed it with keen vigilance for any rapid uptick in angular motion.

The storm then became somewhat less organized (wide angle view while lying in bluebonnets), but we stayed just ahead of it, aiming now for dinner in Gainesville and a ride home up I-35. With the ongoing loss of diurnal heating, I figured this would be the storm’s last hurrah. Still, it treated us to some spectacular twisting and banding (horizontal and vertical shots at 17 mm full-frame) between Saint Jo and Muenster. The last shot was deja-vu, in that it reminded me a lot of a wondrous scene that Elke and I witnessed a few years back outside of Hyannis NE — similar vertical banding, but without the residual supercell updraft at its southern root.

We ate dinner in Gainesville while the dying storm moved overhead, spitting a little lightning and rain, but not much else.

This was a fun, interesting and at times quite scenic intercept of a long-lived, non-tornadic “cold core” supercell in north TX. [Yes, I know there’s a tornado report by a local fire department in the rough log. I have seen no confirming evidence as yet. We had excellent views of the storm throughout that phase, and there were lots of hangy-downy scud foolers under the wall cloud at times. So I await unambiguous photos or video before believing the report.]

It was the best storm observing trip of the year yet, with hopes for many more! It also was a great dad-kids time. Last but not least, I ought to mention that Al Moller came to mind while I was belly-down in the bluebonnets, and those who know Al know why: It’s exactly the sort of scene he has specialized in shooting with amazing skill for a long time; but he’s got far better shots than that one in his slide collection.