2012 Season-Opening Success in Southwest Oklahoma

March 21, 2012 by · 1 Comment
Filed under: Summary 

18 Mar 12

SHORT: Intercepted merging storms then resulting single supercell over SW OK, with spectacular structure and three short-lived tornadoes.

LONG: A little advanced planning made possible a splendid start to the 2012 storm-intercept season, on the 87th anniversary of the Tri-State Tornado.

Before Tornadoes

My daughter Donna and I headed out from Battlestar Norman at 19 Z, thanks to 1) her outstanding academic performance and judicious spring-break homework planning that freed her this time to chase, 2) her ability to drive to meet me at work, and 3) Greg Dial’s swapping shift hours with me from the previous day. It was a good day for some dad-and-daughter time on the highways and byways of southwest Oklahoma. We targeted the LTS/CDS area, well-advertised for a few days as part of a corridor of dryline supercell potential.
Forecast thinking was that early cloud bases would be somewhat high, but storms likely being discrete given the presence of modest capping and decent component of mean-wind orthogonality relative to the dryline. Low-level and deep-layer shear would be more than sufficient. Boundary-layer moisture would increase as storms moved off the deeper mixed layer air of the dryline environment, deeper into a moist sector.

As we cruised W across the N side of Lawton (S edge of FSI), we started to experience promising breaks in the low clouds, while the first robust reflectivity echoes sprang up SW of CDS and E of Crosbyton. I immediately targeted the northern echo because it would be moving into: 1) the forecast target area, with a somewhat more favorable environment slightly sooner, and 2) a better road network over SW OK than for the storm headed to the Crowell area. Both of these would evolve into supercells eventually, along with a third echo farther S.

As we approached Hollis, the small, young storm came into view, still well to our SW near CDS. Being a softie for abandoned structures of the Great Plains, I couldn’t resist parking at a wondrously decrepit old house, located 3 E of Hollis.

The westward-listing relic of the homesteading era creaked in the wind, as if mournfully moaning some of the last words in its long and mysterious life story. A loose strip of sheet metal on its roof flapped hither and yon in the prairie wind, its clanking noise advertising the structure’s vulnerability for all to hear, but with only us listening. Yes, the old house was well worth shooting, both in its own right and as a foreground for the approaching storm.

Moving generally toward us, the storm became better organized, until distinctively supercellular bands and striations materialized. We repositioned a couple miles east to distance ourselves from the vault’s lightning production, while its base expanded. Another rotating storm formed just SW of the Hollis storm’s flank and moved NE, dumping its own front-flank precip into the back edge of the first storm.

Cloud-base spin began anyway, along with intermittent pockets of faster rotation and rising motion with lowerings (looking W). The first serious occlusion wrapped a good deal of precip around the low-level mesocyclone, with a short-lived, conical, rotating lowering that might be termed a ragged funnel cloud.

Meanwhile, as our gradually merging storm(s) got messier, things got very interesting 60-70 miles to our S. The classical, flying-eagle reflectivity appearance of the middle (Crowell) supercell tempted me enticingly, especially when the red polygon showed up. Despite that storm’s digital allure, we stuck with the northern storm based on visual cues, even through its struggles with mergers and resultant HP-like precip cycles.

Here’s why. The storms’ merger cast a lot of messy precip across the scene, but somehow didn’t kill the initial supercellular rotation area. We would stick to our original target. This was purely an “eyeballs” decision. On reflectivity animations it did look like a disorganized mess. Visually, it still was conducting a series of occlusions. Good thing I trusted my eyes more than radar this time!

While I’ve found wireless radar access generally to be a benefit in the years since its availability, this event was a fine example of how onboard radar access sometimes can be a curse instead of a blessing. When visibility sucks, and all you have to work with is radar, you go for the storm with the best organization, if the environments are somewhat similar. In this case, however, the nowcast environment also was a little better for the northern storm in terms of slightly weaker CINH, and similar to slightly stronger SRH in another 2-3 hours. It was a gamble of patience that paid off.

First, however, the messy, temporarily HP storm character brought down contrast (wide angle view looking NW) as the whole process churned northeastward. A new area of rotation developed ahead of the old, rain-wrapped circulation, as the storm(s) gained distance from us. It was time to reposition N and E through Shrewder. This meant going N six miles on a narrow but hard-packed dirt road if we were not to lose visibility. One stop W of Shrewder afforded us a view of a new and old meso with rainy pseudo-nado (looking NW). Meanwhile, that portion of the second (merging) storm that appended itself to the flank of the first began to exhibit some wild striations nearly overhead to the SW.

Upon seeing that, I knew the combined storm was evolving into a wedding-cake special, and we needed to get many miles farther NE to get enough of the storm in view for decent structure shots. We zigzagged through Russell and Mangum toward Brinkman, watching a couple more occlusions and short bursts of moderate cloud-base rotation. One stop near Russell afforded us this splendid view to the NW. We turned W from US-283 onto a paved road running S of Brinkman, looking SW toward the Reed area, and toward a stunning, sculpted supercell.

Tornadic Stages

While admiring the structure, I spotted something tubular emerging leftward (southward) from either within or behind a rain core under the base. Donna shouted over the wind, “Hey dad, is that a tornado?” I shouted back “Yes!” and managed to snap just one photo of the serpentine vortex (alas, with the 24-70 mm glass still attached…here’s a cropped version) before I reached into the car for the zoom lens. Time was 0004 Z. By the time I got the 300-mm lens on, the little tornado was gone, the area where it had been exhibiting only a scuddy lowering and some precip filaments. I don’t know how long the tornado existed before it popped out of the murk, but can’t imagine more than a minute or two. I called it in to the WFO, advising that the tornado had dissipated. [A couple of subsequent attempts to call during later events would be met with busy signals.]

Remarkably, this was Donna’s first tornado on a chase! She soon would add two more. Donna had been on 15-20 tornado-free storm intercepts with me over the years, and had seen three tornadoes while not chasing.
Staying in the same spot, we let the storm approach rather uneventfully, watching one more non-tornadic occlusion occur, then decided to head back east and gain more distance for structure shots. As I drove, Donna and I (she with direct sight, I via rear-view mirror) each noticed a smooth lowering forming in a somewhat rain-wrapped mesocyclone to the distant WNW. We turned around and pulled over at the first safe vantage, 5 E of Willow OK, right alongside Bruce Haynie and his chase partner Matt from LBB. The lowering was a funnel that rapidly became apparent as a tornado. Time was 0029 Z.

The condensation tube fattened into a tilted, tapered cone, while the clear slot eroded more ambient cloud material and a core dump grew to pseudo-tornadic form elsewhere in the mesocyclone area. A real tornado and a lookalike, all in the same view! Here was a 300-mm zoom at 0029 Z, seconds before the tornado appeared to dissipate.

Dense precip filled the entire mesocyclone below cloud base, and we started heading E again. We were just half a mile W of OK-6 and 7 N of Granite when another lowering showed up in the rain–tornado 3. This time, contrast was very poor, as was my attempt to photograph it (see deeply enhanced version). Time was 0039 Z.

Better vantages were had from both closer and farther away, and more to the NE. At this moment, I was located in that netherworld between close enough for a good shot of the tornado, and far enough to pull out structure. Sometimes a storm observer’s timing is off that way, but I’m not complaining…Donna got to see her third tornado of the day. Shortly after the tornado roped out (within a minute), we noticed a suspicious cloud lowering deeper into the precip, probably in an older occlusion. The feature was just too distant and low-contrast, beyond intervening trees, to determine its nature (severely enhanced crop).

Post-tornadic Period

On the way to Retrop, we stopped to view the majestic and now non-tornadic storm, exuding ghostly pastels in early twilight, here at wide angle looking NW with a mobile radar that wasn’t scanning. When we turned back onto OK-6 to head N, we saw that the radar truck was parked smack in the traffic lane–since then I’ve learned that they were broken down in that spot instead of stopped intentionally.

We stopped one last time, a few miles E of Retrop, to watch the storm go elevated and weaken in the deepening twilight. We were satisfied beyond measure with our first chase of the season, and fortunate to have experienced such a phenomenal storm with minimal hassle. We managed to avoid the worst of the chaser hordes, and saw generally safe behavior even in traffic.

Given the late hour by the time we reached the next sizable town (Cordell), celebratory steak dinner would have to wait until the next day. We did, however, enjoy some Sonic food, followed by a little more dad-and-daughter time on the couple hours’ drive back home.

[EDIT] Post-chase, I learned that my camera clock was 6 minutes slow. The clock has been reset, and the times above corrected.

November to Remember

November 13, 2011 by · 2 Comments
Filed under: Summary 

Tornadic Supercell in Southwest Oklahoma
7 November 11

SHORT: Intercepted two nontornadic supercells and one tornadic in SW OK. Witnessed multivortex tornado move through wind farm, among others.

LONG: This has been a very fortunate year for me for storm observing, and a rare juxtaposition of a day off with a November chase day offered the promise of icing on the fine tornadic cake that has been 2011.


For several days, a classical, spring-like, near-dryline supercell setup appeared to be looming…in autumn. Looking at the morning charts and RAOBs, the presence of very nearly surface-based effective inflow parcels even during early-mid morning (using FWD and OUN soundings) reinforced my main concern–the potential for early initiation, maybe too many storms too soon. Otherwise the foci for supercell and tornado potential looked fairly well-defined, the target area compact: approaching, progressive shortwave trough aloft with deep-layer shear strengthening throughout the day, adequate moisture return, backed winds, and enhanced low-level vorticity along an outflow boundary E of a dryline and cold front…all in the southwest OK/NW TX area.

After morning appointments (I try to avoid scheduling any immovable commitments for afternoons even in the “off-season”), visible imagery showed good clearing from the southern tier of OK counties (LTS-FSI) southward, and towers already starting to deepen in the weak CINH even before noon. The deepest warm-sector convection already was forming near 100W (TX/OK border longitude), with other clumps of shallower convection farther ESE over NW TX. Time to head out the door!

Early, non-tornadic supercells

Perhaps I left a little too soon; this is a longstanding bias of mine. Still, I targeted the LTS area via the NE (HBR) instead of E (FSI), in case any decent storm rode up the western fringe of OK and into the baroclinic zone. I’ve had a few successes with early-event tornadic storms tucked in the NW side of a SE-expanding storm regime, and a supercell SW of Mangum was getting larger.

By the time I reached Lone Wolf, on the way toward Mangum, a messy cluster of storms with some banding and supercellular tendencies had formed to the SW (wide-angle). I considered staying near there, and perhaps should have in hindsight, given a few observers’ later reports of a short-lived multivortex tornado with an eventual supercell SW of HBR. Instead, I headed to the western storm, somewhat concerned that my onboard thermometer indicated only the narrowest of slivers of diabatic warming between the HBR cluster and the now tornado-warned Mangum storm.

The western storm came into view NW of Mangum; I parked 2 WSW Brinkman to let the storm move just to my W and N. It was somewhat pretty, but not too promising. An earlier, distant wall cloud had vanished, and the storm looked rather strung-out. A new mesocyclonic cycle yielded a weakly rotating, nice-looking little wall cloud, but it couldn’t tighten up and produce. Moreover, the probability it would was dropping by the minute; inflow air was getting cooler! Naturally, the storm started to weaken.

By this time, a small cell I earlier had noted on radar, S of the Red River and S of FDR, had exploded and was taking on obvious supercellular signatures. I was out of position for anything it would do in the next 1-1.5 hours, and knew it. But I also knew it would have a long potential trek through vorticity-rich air of at least marginal buoyancy, all the way N of the Wichita Mountains, if no other storms erupted to its S or SE. For now and for hours, that southeastern storm would remain unimpeded that way.

I wasted no time in deciding to go toward the FDR storm, but two other supercells were in the way: one just SW of HBR (the early multivortex producer I missed) and the other slightly farther SW, also approaching HBR. My best chance at shooting the gap between these two supercellular obstacles and stay on course for the southeastern storm was to head back through Lone Wolf to HBR, around the northern flank of the southern-middle storm and S of the hook of the northern one (beautiful rainbow scene on their collective W side). I threaded between the two most dense core regions; but the gap was small and I did encounter some small to marginal-severe hail in the southern (nontornadic) HBR storm’s forward flank. Here’s a wide-angle look at the southern-middle storm between HBR and Roosevelt, looking WSW.

Turning S out of HBR, my timing looked barely adequate, and more likely too slow, to reach the FDR storm S of the Wichitas. By now, I already had heard of a couple of tornadoes it had produced; and the storm appeared to be trucking along nicely with a powerful low-tilt velocity signature. Instead of trying to stern-chase it on US-62, only to encounter a road void in the Wichitas, I chose to head E out of Roosevelt, skirt the storm’s northern flank, and wait N of the Slick Hills for the supercell’s business end to come toward me. I knew the massive, E-W oriented Blue Canyon Wind Farm was a couple miles S of OK-19 too, right in the meso’s path, and might provide an interesting foreground for whatever emerged from the rough terrain. It would be my first correct strategic decision all day.

Post-Wichitas phase of tornadic supercell

Heading E from Roosevelt, I could see some of the rear-flank convective wall of the FDR supercell to my S; while a very bright rainbow with secondary accompaniment festooned the fringes of its left-flank precip core. I zigzagged the necessary roads toward the area NE of Saddle Mountain, encountering more mainly sub-severe hail in the tornadic storm’s northern rim. The hook echo was very impressive on radar, when I had any phone data in this reception-deprived area, with one scan of ~100-kt gate-to-gate shear. By now, I was preparing for the possibility of a big tornado coming out of the mountains and through that wind farm.

A fine viewpoint appeared ~5 SW Alden on OK19, with a surprisingly green field of winter wheat leading SW toward the ridge-top wind farm. The mesocyclone’s orbiting rim of cloud-base scud came into view to the SW, circulating at impressive peripheral speeds that I’ve seen only with tornadic settings. The meso was translating directly toward me, but still with plenty of time to spare and a good escape route eastward. Time to rock and roll. Alas, a furious bombardment of close CGs kept me under within the vehicle for several more minutes. A group of unrecognized chasers showed up at the same vantage, standing outside rather unwisely despite the occasional CGs still hitting within hundreds of yards.

Fortunately the electrical attack from above abated fairly quickly, and we all could concentrate again on the approaching mesocyclonic menace. I was very confident a tornado still was lurking beyond the ridge line near Saddle Mountain; and within minutes, that suspicion was confirmed! The visible condensation funnel of the tornado, still beyond the ridge, vanished from obvious view for a minute or two, the visible parts of the cloud base seemingly boiling with furious movements. The tornado reappeared even better. I strongly suspect this was the same tornado as before, given
1. Its temporal and spatial continuity relative to the ambient mesocyclone circulation, and
2. Later TV-chopper videos I’ve seen of the Saddle Mountain tornado, which dissipated right before reaching the wind farm.

A new, strongly rotating wall cloud formed N of the dissipated tornado and over the western part of the wind farm. In fact, its base was so low that the turbine blades extended into the cloud! The new circulation also extended E of the visible wall cloud, which seemed to subsist on recycling of rain-cooled air from the precip wrapping around the N and NW sides of the hook. This fascinating process was about to get more so, and fast.

On the E (left) side of the mesocyclone, slightly displaced from the lowest part of the wall cloud, a multiple-vortex tornado, containing a dominant central condensation tube, developed over the wind farm. This was obviously separate from the earlier tornado. Since some of my home’s power comes from this wind farm, I was hoping against its destruction; in fact, as the tornadic circulation continued to swirl through and around the turbines (wide view and cropped), I saw no clear evidence of damage.

Small suction vortices occasionally formed and pirouetted gracefully among the turbines (wide view and cropped), as the main cone became more sharply defined (wide view and cropped). The entire scene was strange and ironic — a wind farm under siege from the ultimate in “wind power” (wide view and cropped).

Through the whole ordeal, the disabled blades held firm, not budging nor popping loose, despite the undoubtedly intense mechanical stresses. The functional turbines seemed to adjust their alignment (with some lag) to the mesocyclonic wind shift, but of course, couldn’t do so fast enough at tornado-vortex scale. The blades’ rotation speed seemed to remain fairly steady, which fits the purposeful design of such machines to brake the spin rates in order to minimize damage in extreme wind. This certainly qualifies as extreme wind!

A powerful, precip-laden RFD surge hit the tornado, weakening it while sending the remains of the circulation careening ENE through the N side of the wind farm, at an oblique angle. A newer mesocyclone was tightening up rapidly, immediately (just over a mile ) to my SW, so it was time to reposition a tad east. While driving, a glance in the right-side rear-view mirror revealed a new, entirely separate tornado developing as a tall, slender tube. This pretty, partially rain-wrapped tornado (the third for me so far) only lasted a couple of minutes, dissipating as it reached OK-19 near where I had parked before.

This newest mesocirculation, with wrapping rain curtains, shot toward the NNE beyond OK-19. I headed E a little over a mile to OK-58 then N, watching it weaken as it obliquely approached the road to my immediate WNW. The mesocyclone dissipated fast. Still, rain curtains seemed to be moving fairly quickly in assorted directions around me. Frequent glances at the cloud base above revealed strengthening, convergent westerly flow. I soon saw why.

Yet another quick occlusion was about to occur, as another mesocyclone developed a short distance to the E. This was not the optimal position for any storm observer to occupy, so I searched for a good E option that would take me out of the backside of the hook. [Fortunately, the storm continued its trend of producing non-damaging hail with respect to my vehicle.] Now WNW of the new circulation, I turned E on E1380 Road toward “Pine Ridge”, a crossroads with neither a ridge nor pines. The road was reasonably well-drained, alternating between paved and hard-packed gravel with occasional shallow puddles, and was good to go at 50-55 mph in high 4WD.

Right after my turn, a fuzzy cone tornado materialized to the ESE, allowing a brief stop to photograph it before the rear-hook firehose started dousing me. The white smudge in the last shot, below and to the left of the tornado bottom, was a hail splash.

Back on the road again, I carefully approached the mesocyclone and tornado from the W, watching the latter dissipate and the former rotate intensely as it crossed E1390 about a mile away. This circulation moved N, and yet another one (the eventual Ft. Cobb tornado producer) developed just to its E. By now, the storm definitely was translating poleward and speeding up, getting away from me even as I drove the short few miles to my N turn on N2550 at “Pine Ridge”.

Seeing occasional multivortex filaments form under the new circulation (the Ft. Cobb tornado), I stopped briefly to photograph the storm structure with the mesocyclonic cloud base below (deeply enhanced crop-n-zoom). Heading N toward Ft. Cobb, I could see occasional plantings of full ground-cloud condensation; but every one of the 4-5 times I tried to pull over and photograph them, the condensation would go away. Daylight and contrast each grew dimmer also.

After escaping Ft. Cobb, I drew closer to what was left of the circulation near Albert, its cloud base still rotating and low-hanging in the twilight, but obviously weakening. I couldn’t complain much, though, I had found my fifth tornado of the day, a pretty remarkable feat considering some poor tactical decisions early in the afternoon that caused me to miss a fantastic tornado show SW of the Wichita Mountains.


The trip back was mercifully short, as the former FDR-Ft. Cobb supercell got absorbed ingloriously into a building band of storms near Okarche. How often does one arrive home by 7 p.m. after a multi-tornado intercept? Despite what I had missed, these were my latest tornadoes seen in a calendar year, and multiplied by six the sum total of lifetime November tornadoes.

To make the day truly unique, I got to experience an earthquake too. Not long after settling in at the house, a low, thunderous rumble and weak vibrating of the house signaled the magnitude 4.7 aftershock from the Sparks earthquake swarm that had been rattling off and on for several days. I had felt the Oklahoma-record magnitude 5.6 shaker a couple of nights earlier while in a cabin at Greenleaf State Park (my first ever). With multiple earthquakes and tornadoes witnessed in a 3-day span, it was a marvelous time for an earth scientist in Oklahoma. 2011 also has been, by far, my most prolific tornado year.

As with the 20 June tornado-fest in Kansas and Nebraska, I sent an itemized table of tornado times and estimated locations to the WFO, with embedded links to many of the same photos as above. That table includes times, locations and links to the photos. What had been listed as one tornado on coarse-resolution maps, from S of the Wichitas to OK-19, should become three in the final record. The tornado log file is in the public domain, and linked here in MS Excel format, freely accessible for anyone interested.

Central Oklahoma Tornado Outbreak

June 4, 2011 by · 1 Comment
Filed under: Summary 

El Reno/Piedmont, OK EF5 with Satellite Tornado
Dale, OK EF1 Tornado
24 May 11

SHORT: Intercepted tornadic supercells NW and E of OKC, the first with a violent tornado in progress, the second offering a scenic rope-out.

Welcome to a “High Risk” outlook and “Particularly Dangerous Situation” watch scenario that verified, weather-wise, exactly as such for central Oklahoma: in summary, three different violent (EF4+) tornadoes arose beneath three different supercells, with a fourth big tornado rated EF3 in northwestern Oklahoma (NWS Summary). Through both skill and luck, we witnessed what has been rated as the biggest and baddest tornado of the lot; yet we are respectfully mindful of the human toll that it took in spite of absolutely outstanding forecasts and warnings.

This almost classical Southern Plains tornado outbreak was so well-forecast and so thoroughly handled by SPC, local offices, local media and EMs, that I’ll eschew discussing meteorological details, offer a few prototypical 21Z (4 p.m.) mesoanalysis graphics that pretty much speak for themselves…

    MLCAPE and CINH | Effective Bulk Shear Magnitude | Effective Storm-relative Helicity | Observed ~850-500 mb Crossover | Effective SCP | Effective Sig. Tor. Parameter

…and now go straight to “the chase”. And what a “chase” it was, right into the area of maximized parameters you see on those linked mesoanalysis graphics, and at about that time.

Phase 1: Intercepting the Piedmont Supercell

After looking at some data at home, and at Ryan Jewell’s house, Jack Beven and I targeted the area near and just N of I-40 in west-central OK, mindful of the likely fast storm motions of the day and the need not to get too close, to soon, to developing storms. As we headed W on the big slab, the earliest cell of consequence erupted SW of Fairview, not too far from the previous day’s tornadic intercept. Indeed, though we didn’t target the storm due to incompatible relative motion vectors of it and us, it would produce a couple of tornadoes over and near Canton Lake.

Storms were forming closer to each other than I like, causing some interference and precip-ingestion problems. We waited just E of Watonga for the next supercell in a broken band of them, hoping to get a quick look while ultimately targeting the southern storm in the same grouping–the storm that would become the El Reno/Piedmont supercell. A quick jog back W to the fringes of Watonga, as the storm passed, revealed an outflow-dominant heap; so we flipped the vehicle back eastward, heading for Kingfisher and the next decision point.

As we got to Kingfisher, the big deliberation was: wait for the storm E of town on a good E-W road and risk that it would right-move to the morass of stoplights and traffic of Guthrie, or head S on US-81 to Okarche and risk munching some of the forward-flank hail along the way?

The radio station was blaring frantic TV simulcast reports of a “wedge” headed for El Reno. We vacillated for a couple of minutes, and I had my doubts; but Navigator Jack’s front-of-the-map calculations convinced me we could pull it off. We headed S toward Okarche into dreadfully darkening murk, intensifying rain, and ultimately, some hail, while hearing of the same “wedge” crossing I-40. Often such tornado descriptions are exaggerated; but I knew that, on this day, violent, large, and long-track tornadoes certainly could happen. Unknown to us, at the time, the tornado was sideswiping the El Reno Oklahoma Mesonet site with an 18-mb pressure drop and measured gusts to 151 mph–the strongest winds yet clocked by that network of weather stations.

Rounding the SE turn onto OK-3, we vectored an intercept position for any tornado coming NE out of El Reno. Blistering barrages of close CGs hammered the ground all around us, a fusillade so furious that I pulled my radar-delivering I-Phone out of the car jack, and we refrained from touching anything metal. A few hailstones clunked off the roof–none ultimately large enough to do damage, though we did see stones around two inches in diameter bounding off the road. The really huge and destructive hail was no more than a couple of miles to our S and SW; we had left Kingfisher in the nick of time to get around it!

We pulled S off OK-3 at Cimarron Road, about 5 WSW Piedmont, and drove S about a mile to a fine hilltop vantage. CG activity was backing off a lot, and we were (for now) out of precip. I could commence photography in relative safety. It was so stinking dark under that storm that I had to crank the ISO up to 1600 just to hand-hold shots with 1/25-1/60 sec shutter speed at f2-f4! At a time like this, I was so thankful for having invested in a top-end Canon DSLR and the L-series glass on the front. Using lesser equipment and especially with my old slide camera (which usually contained 100 ASA film), successful collection of the following shots would have been impossible.

And so we waited, looking along a lengthy cloud base from W-SW, footed by some dark murk well to our SW. We knew where the tornado was from the constant TV reports–buried in that murk–but couldn’t quite see it yet with our eyeballs. In fact, it was only after I took this 34-mm shot at 1630 CDT, then looked at the viewfinder presentation of it, that I finally could ascertain the outline of the tornado embedded in that murk to our SW (severely enhanced crop of same photo)! It was moving NE (toward us) at 40-50 mph. We had several minutes to hold position before having to decide whether to jog S on our paved, N-S road to get out of its way.

At first a multivortex containing a fat, tilted stovepipe, the tornado took on a wider configuration with a fat barrel and adjoining cone being two of the more persistent, larger tornadic vortices involved. Even at that distance, we began to make out wild cloud motions and rapid revolution of vortices around each other. The barrel temporarily vanished at 1632 CDT to reveal a fat stovepipe within an obviously significant, broader tornadic circulation.

Despite all the precip evident to the left (SW through SE) of the tornado cyclone, it maintained enough of a weak-echo moat around its immediate vicinity that our view kept getting better and better. The tornado also was growing larger as it got closer, closing in fast, not moving much right or left. This meant we likely would have to bail S sometime soon. But first, more observation and photography ensued as the tornado’s form fattened into a wide, dust-flinging barrel, then a bonafide wedge. The ambient wall cloud and occlusion-downdraft slot also became more apparent, contrast and visibility continually improving for the time being. We were impressed…very impressed. I told Jack, “Congratulations…your first violent wedge tornado.” Jack has been taking chase vacations to the Great Plains since the mid-1990s, often with the most deplorable luck in weather patterns. This was a new and potent experience for him.

As this grinding behemoth drew closer, I was supremely confident in its violence, while dearly hoping nobody was sheltering above ground inside its path. [I didn’t know it at the time, but this monster had killed several folks already around I-40.] The motions in and around the tornado were of a ferocity I’ve seen, in person or on video, only with tornadoes ultimately rated F4 or F5. As the sides of the condensation wedge appeared to froth and oscillate wildly, chunks of scud materialized at ground level in incomprehensible fractions of a second and raced diagonally up the and around the vortex at breakneck speed.

Given its slight rightward translation, I was reasonably confident the tornado would miss our location–but not my much. Any rightward turn, however, and we would be in grave peril with precious little time to spare. At 1635 CDT we turned S and drove a mile. As we pulled back onto Cimarron Road, a well-defined, horizontal accessory vortex formed on the near (NE) side just above ground, coiled around the N side, and rolled vertically up the rim of the tornado. This was a new experience for me, having seen the phenomenon only on videos of violent events such as Red Rock OK (26 April 1991), Golden Gate IL (2 Jun 1990) and Tuscaloosa AL (27 Apr 2011). Had I stayed at the previous location 30 more seconds, I could have photographed that too.

As good luck would have it, the tornado took a temporary NNE jog as we rolled S, maintaining safe distance. As bad luck would have it, torrential rainfall began wrapping around the SE and E sides of the mesocyclone, thoroughly dousing me in a veritable firehose of water after I jumped out and ran into photographic position. Barely able to stand in the roaring inflow, I hoped for just a shot or two before the camera would get too wet. It grew into a very wide, menacing wedge all the while, its collar cloud blasting around the mesocyclone with amazing speed. As the tornado moved to our WNW and NW, I clearly heard its roar–a throaty, primeval rumble somewhere in pitch between the closed-mouthed growl of an angry bear and the muffled booming of continual heavy-artillery fire.

This was one bad, bad, bad mother.

I reeled off one final good shot at 1638 CDT–capturing a satellite tornado that had just emerged from behind (W of) the big one, and was orbiting around its near-SSE side, throwing up a dust plume of its own. The satellite then turned NNE in front of the main event’s E side, and became lost in worsening contrast. The last and only other satellite tornado I saw was on 3 May 1999, near Chickasha.

Within seconds, the big tornado right-turned ENE again and got so wrapped in rain that we barely could see it anymore. It crossed OK-3 just W of Cimarron Road, and as we cautiously crept N back toward OK-3, crossed Cimarron road less than a mile to our N. Needless to say, I was glad it was moving away from us, while glancing overhead and around often for more satellite vortices. Furiously wrapping rain curtains parted just enough to reveal the E edge of the condensation vortex to our near-NNE, rightward of some power flashes. This was my last clean view of any part of the tornado, at 1640 CDT.

Meanwhile, the combination of inner-edge RFD plus southern-rim inflow to the tornado was severe at our location. The forward housing for my outside rear-view mirror launched itself like a rocket off my vehicle and sailed airborne for hundreds of feet out into a field to our NE, as the vehicle shook in the gusts. We were safe (barely), but also, not inclined to go any further N for a minute or two.

Even though the tornado did miss our initial photographic location, it wasn’t by much. I’m still glad we moved…under half a mile from the edge would have been unsafely close for a certifiably violent, still-expanding, precip-wrapping monster with proved tendency for satellite tornadoes and accessory vortices writhing around its rim.

Then hit a horrifying realization-–this tornado was headed generally toward the residence of my friend (and fellow storm observer) Rocky Rascovich, N of Piedmont. I tried to call and nobody answered; fortunately, it turned out they already were in shelter. His wife assured me later that it (barely) missed them and they were OK. It was the sort of tornado–fast-moving, expanding, wrapping in rain–that is the most dangerous and hardest to observe safely.

Later news of the deaths near El Reno and Piedmont humbly counteracted any sense of gratification I had that evening at getting the good-contrast, big-wedge shots about which I had dreamed since childhood. This is the ethical paradox and dichotomy of conscience for any storm photographer.

Phase 2: Intercepting the Dale Supercell

Cruising along the mostly empty Kilpatrick Turnpike (around N OKC) we briefly debated whether to go up I-35 and meet the storm at Guthrie; but its deep precip-wrapping and messy radar appearance convinced us to jump SE for newer storms headed out of the Chickasha area. Early reports of tornadoes from those sealed the deal.

Jack and I tried to get S of Norman, but were stopped by a traffic jam on I-35 in town (flipped car unrelated to tornadoes) and couldn’t get to Goldsby readily to observe that event. Had the Goldsby tornado turned slightly more leftward and gone up I-35, it could have plowed through hundreds of stopped vehicles up and down the highway!

Instead we waited a short time near the North Base for what was left of the Newcastle storm (by then, nearly nothing), then backtracked some back roads to I-240/40. Along the way I spoke to Elke; they headed to my neighbor’s underground shelter as the Goldsby event headed for Norman. In northern Norman and along I-240/40, Jack and I encountered occasional marginal-severe hail and falling small debris (insulation, leaves, small twigs) that had been launched by the Goldsby tornado into the supercell’s far-forward flank.

The Goldsby storm also had been slammed by a left-mover, temporarily disrupting its organization, dousing the once-violent tornado before it could grind through some part of Norman. I was glad of this, as it spared a lot of destruction in the town in which I reside!

As the supercell reorganized, we vectored the new mesocyclone to cross W of Shawnee near Dale, in a mostly hilly and forested area. Fortunately I knew of a large, flat, open field just S of the I-40/OK-102 (Dale) exit, from which I had photographed the OKC ice-machine storm of 16 May 2010. We headed there and waited for the reorganizing mesocyclone region from the approaching supercell to come into view.

From the murk, at 1830 CDT, a low-hanging, conical cloud form appeared to our W, hard to see at first beyond the red farmhouse in the last shot (super-enhanced crop). This feature had good temporal continuity with what would emerge more visibly by 1832 (super-enhanced crop)–the Stella-Dale tornado, as a tilted cone beneath a deeply clear-slotted wall cloud. We weren’t totally sure yet by our eyes, even then (given the hazy conditions); but by 1833, it was obvious that a tapered cone tornado with debris fan (super-enhanced) was moving in a general ENE direction to our WNW, very close to I-40.

As the tornado grew closer, its form gradually became sharper and also more sinuous, contorting spectacularly into a long curved tube. I was so mesmerized by the wondrously serpentine evolution of the visible vortex that I didn’t think to slap on the zoom lens until the tornado roped out at 1836 CDT. What was left of the mesocyclone next moved N of us, got undercut by rain and outflow, and vanished into the murk N of I-40.

We cruised E on I-40 to look at two more supercells near Prague and Okemah; but their structure was more amorphous, with little evidence of robust low-level rotation by that time. Along the way back, we noticed mostly minor (Ef0-1) damage alongside I-40 2.5 W of the Dale exit, where the tornado crossed. The wreckage of the big rig, whose trailer got blown to pieces, still was being hitched up to a towing vehicle.

By the time we got back to Norman, we were thankful that my home (and those of others in Norman) was spared, and that we got a high-contrast view of a violent wedge…but also, once again saddened for the casualty toll from yet another deadly tornado day among far too many this year. We met up with the Fogel crew for dinner (they had far worse luck than we with tornado observing on this day), as well as Elke and my kids, swapping stories of a great chase (us), a frustrating one (DF’s crew), and another Norman scare (my family). Aside from a dollop of mental exhaustion, my other impression was: “I’m about ready for the High Plains!”