Storm Observing Drama in Four Acts
Southeastern WY near Cheyenne
7 Jun 12
This storm day was striking in that it unfolded as a four-act drama–each one quite distinctive, essentially a quartet of distinct chases in one day. Seldom have I experienced so much logistical and emotional ups-and-downs in such a small area in one trip! We went from intense frustration to elation and satisfaction, with one or two minor dollops of danger thrown into the storm-intercept recipe for good measure.
Act I: Early Poor Decisions and Frustration
Elke and I targeted southeastern Wyoming for the potential of a supercell or two forming in a region of decent upslope lift . As we headed W from Pine Bluffs WY toward CYS, a storm formed in the Laramie Range and stem-wound itself into an intense supercell while still in high, rugged terrain. It turns out that storm formed as a pyro-convective plume off the Cow Camp wildfire, and became tornadic while still sucking smoke up in the mountains.
[NOTE: The write-up in that link does contain one major error–tornadoes cannot “skip”. By definition, if it’s “not on the ground the entire time”, it’s not a tornado the entire time! As such, each segment had to be a different tornado.]
We arrived in CYS intending to head N on I-25 and intercept that supercell, or whatever was left of it, somewhere not far N of Chugwater. Then a new storm exploded into the Wyoming sky just to our NE. A bit of indecision followed, before we made the fateful choice to take a look at the younger cell. The storm farther away looked better on radar, but the new one was right there! How do you blow off a storm blowing up practically in your lap? We should have. This move ultimately cost us any shot at a decent view of the Wheatland/Chugwater tornado(es).
We headed the short distance back E toward Burns and then N, finding that the newer storm was shriveling, while the fire-generated, tornadic supercell to the NW still was going (and still had a likely tornado, given its radar signature). I was not happy. Still, zooming up US-83 toward the west turn to Chugwater, we thought we were in great position to intercept the big supercell while still tornadic. Indeed, given the official timeline for the event and our terrain-truncated vantages, Elke and I are now sure we caught some glimpses of a cylindrical, mostly rain-wrapped tornado just over the high ridge line in the distant WNW, while driving.
I turned the vehicle W on WY-314, seemingly in ideal position to catch the end of the tornadic stage, and then about 8 miles along…a one-lane road, pilot-car closure with no pilot car! This was about when it seemed that our chase day just wasn’t meant to be. One lone lady in an orange vest was standing there with a flag, stopping all westbound traffic–most unfortunately, in about the lowest bottomlands where neither she or we could see diddly-squat.
Diddly-squat, in this case, consisted of a tornadic supercell and its approaching forward flank. We told her about the storm, its likelihood of lightning, skull-cracking hail and flash flooding…but she seemed oblivious, and totally dependent on a radio dispatcher who was (quite irresponsibly) giving her no information at all about the storm. She finally assured me she would crawl into a nearby tinhorn if it “got bad”–which wasn’t much assurance with regards to her safety. Other than that culvert, there was nothing out there in which to take shelter! Alas, that was the best I could do to convince her she was in potential danger.
Thus thwarted, we turned around and headed E and uphill several miles, finally getting a view of the storm’s base less then 7 minutes after the tornado is on record as dissipating. [Without the closure, we easily would have gotten on the plateau E of Chugwater in plenty of time to see the last moments of the tornado, across a flat and unobstructed landscape.] The supercell appeared to be getting more disorganized, with newer development to the SW…so we headed back E to US-83 then SSW toward CYS. That turned out to be the first good maneuver we made all day!
Act II: Storm Structure Bliss
As we approached the newer storm, more and more chase vehicles appeared beside and on the road–the only decent road around for miles and miles. It was easy to see why–the storm erupted SE of the first one, right along the way for a lot of observers from Colorado and elsewhere who were zooming up toward the Wheatland storm when it fell apart. By contrast, we came around it from the NE and E, found a vantage to let it move toward us, and marveled at how the structure was getting better and better as it drew closer and closer.
The main updraft base sported a persistent, broad wall cloud with occasionally fast rising motion on the downshear (core-facing) side, but never anything I would call rapid or tornado-like rotation. Meanwhile, the storm-scale formation assumed a sweeping, curvaceous stack across several layers in the vertical.
With a dearth of road options in the general direction of storm motion (SE), we kept letting it come our way until the wide-angle lens needed switching from 24 mm to 17 mm. At one point, I recall telling Elke that I wished I could teleport Al Moller here–he would go absolutely euphoric over seeing this storm in person!
The old wall cloud and mesocyclone area began to assume a more shelf-like appearance as they passed our location, and the entire storm looked a little more disorganized. The only roads back ahead of the supercell led through the core; so we had to retreat away from it in order to reposition.
Act III: Outflow and Hail Machine
We went SW down US-85 and I-25, around CYS, then back E again, then S of I-80 between Burns and Carpenter, for an encore look at the increasingly messy storm. Another supercell also had developed to its east, its updraft base cloaked by precip for the time being; it was menacing Pine Bluffs.
We pulled onto a side road to observe the onrushing maelstrom, greeted by a big, very friendly and rambunctious chocolate Lab, muddy-legged but healthy and well-fed. He probably belonged to a farmstead about half a mile away. The pooch took a running, leaping jaunt through my vehicle and out the other side before we shut the doors! If you ever are traveling with me and happen upon dog-paw prints, that is the reason. He hung around nearby for a spell until the storm spooked him back toward home.
Since we had left it NE of CYS, the western supercell had become more elongated, with a somewhat surfboard-shaped base. Since it was riding its own outflow, this was appropriate! As that storm approached us from the northwest, the Pine Bluffs supercell weakened, shed some precip, and became higher-based. It also trailed a beautiful rear-flank arc cloud that curved right back into the updraft region of our storm (wide-angle view looking E).
Dropping S somewhat to get late-day light under the rear-flank gust front region, we had a decision to make: stay apace and just ahead of the increasingly messy storm and its neighbors southward into Colorado, thereby missing an opportunity for sunset light on the back (NW) side, or go for the colorful view. We usually choose the latter in such situations, and did here, with ease. What wasn’t easy was deciding how. The updraft and main core area each appeared to be weakening some, so one way was to head straight N through the precip and back to I-80. The other was to go W on an unfamiliar road zigzagging along the crest of the Cheyenne Ridge, and hope for a good view before reaching Cheyenne itself.
We chose to attempt the former, and if the hail started getting big, backtrack and do the latter. Just a mile or so into the precip core, we hit a very sudden wall of severe hail that started beating the hell out of the vehicle, somehow sparing the windshield. Spiked bombs of ice bounced high off the road, splashed in surrounding mud, and created sickening booms as they slammed into the metal skin above. So much for the “weakening” core!
Even the quickest of Bo Duke-style turnarounds on an empty road, in a vehicle that is not quite as nimble as the General Lee, couldn’t spare us from its first easily noticeable hail dents. I blasted back S and got out of there before the beatings became worse, then headed W out of Carpenter on Chalk Bluffs Road. We’re so glad too, and not just to avoid demolishing the outside of our ride…
Act IV: Amazing Stormy Skies on the Cheyenne Ridge
Eager to escape the ice monster, we bolted 12 miles W and NW on the road from Carpenter to Cheyenne, the stopped at a very nice 360-degree vantage for one last look back SE at what had tried to turn my finely tuned storm-intercept machine into Swiss cheese. The hail core is at left in the last shot. Yes, it was still a supercell…so what, and good riddance! It was almost time for sunset magic.
But wait…what happened to the sunlight that had been behind the storm we just got behind? All manner of cloud material had developed and masked much of the sky to the NW and W, and a small, left-moving storm was moving from my SW toward the NNE…dragging its precip core toward us. Furthermore, it was rather stinking cold up there on the High Plains ridge–low-50s temps and windy from the supercell’s torrent of outflow!
Just as I despaired over this seeming state of misfortune, two glorious happenings made our day. A mammatus field to our NE, its sunbathing not blocked by clouds, came aglow brilliantly for a few minutes, while casting reflected, bronze-toned front-light onto the landscape to our W.
Meanwhile, the left-mover to our WSW drew closer, strengthened, and unloaded a protracted, stupendous salvo of high-based, cloud-to-ground lightning strikes for many minutes more! Set amidst the warm chromatic ambiance the setting sun, the scene soothed the soul, even as sharp thunderclaps boomed across the miles of chilly High Plains air. Electrical jabs blasted to the ground, truncated up in the air and jolted forth at closer approaches, until we finally had to abandon our post
for safety’s sake.
Heading westward between Campstool and Altvan, through the edge of the left-mover’s translucent core and toward CYS, we encountered a second barrage of hail. Most mercifully were no bigger than dimes, but it was very hard and noisy. Leaving that barrage, our minds were firmly fixated on securing lodging and a hot meal, when a window of amazing color and light briefly opened in the southwestern sky, as if magically. The haunting vista seemed as if we were peering out from within a cave of darkness at an extraterrestrial world light-years removed.
Epilogue: Dinnertime Hailstorm
After getting a motel, we found a Perkins near downtown CYS that still was open, and headed in for a supper that was late, but most welcomed, after a day of wildly fluctuating fortunes out on the road. As we did so, I saw lightning flashes outside, then flipped on the phone radar to see that a high-VIL core was almost upon is from yet another elevated left-mover. The resulting heavy pounding of small hail reverberated through the building, as a small flash flood washed down the low spots. Drifts of the stuff washed through the parking lot and against the wheels of my vehicle–all for our entertainment.
Our third encounter with a hail core was the most fitting way to end the storm day! Everything we had seen since leaving the destructive supercell supported the ideal that long after the main supercellular action concludes, the storm-observing day can proceed with wondrous and spectacular results. For all the lackluster results of the previous day’s storms, this one made up in multiples. Moreover, as of July 28th (this post date), we saw more rain in half an hour in Cheyenne than in Norman during the nearly two months since.
Ice Machine in Yuma, Colorado
Yuma CO, 21 Jun 10
SHORT: Observed 3 supercells ultimately merge into one over Yuma CO — damaging hail, beautiful post-storm skies.
LONG:Join us on this fine, toasty day for a tale of three supercells that became one, the hellish hailstorm that resulted, and a storm-observing couple who chased them.
Elke and I began the day in Sidney with a target area of NE Colorado, in the region of relatively backed low-level flow. We were uncertain whether the storm(s) of interest would fire on the Front Range or on a convergence boundary farther E, in somewhat more moist air SW of Sterling. The answer: yes, and yes! From Sterling, we observed the growing anvil from a storm near DEN that was high-based but starting to rotate aloft (based on radar velocity imagery), along with multiple towers bubbling just to our SW, beneath and S of the anvil canopy.
The tower at left, in the last shot, erupted into a pre-supercellular supercell, before anvil shadowing had a chance to mitigate diabatic heating of its immediate inflow layer. We dropped S to stay ahead of both this storm and the more distant and growing beast roaring out of DEN. Even in this early stage, the new storm displayed nice corkscrewing action (the base of the DEN storm becoming visible at distant rear), looking W from the N side of the Colorado Plains Regional Airport (AKO). The storm spun around for a short while, moving slowly closer to us without growing a very large updraft. Meanwhile the DEN storm churned along essentially straight toward us, with a wall cloud and lowering becoming faintly visible in the distance under its southern flank. I sensed this closer storm wasn’t long for the world.
We headed E through Yuma, taking note of potential hail shelters for four reasons:
-
1. The combination of the big western storm and any merger with a foregoing supercell could spawn some healthy ice bombs,
2. I still had a good windshield and didn’t want to bash the hell out of my new vehicle with gorilla hail this soon,
3. We deemed it wise to plan sheltering options in case we didn’t have time to bail S of Yuma and ahead of any storm acceleration, and
4. The next major town to the E was Wray, its S escape option (US-385) known to be under heavy construction with a surely nerve-wracking and possibly vehicle-destroying situation of one-lane, pilot-car closure for many miles!
Meanwhile, another tower went up in some slightly more strongly heated air several miles farther S (to our SW), also evolving into a skinny supercell rather quickly, and likewise coming under the sprawling and thickening anvil of the onrushing western storm. In the last shot, from just E of Yuma, the outflow-surfing updraft base of the massive western menace is visible at distant left, and its downshear anvil canopy distant right — dwarfing the nearer but much smaller supercellular plume. The older tower (spinning down to its N) eventually merged with the northern part of the newer, closer supercell as the latter expanded. Then it expanded further and assumed some sharply sculpted structure, moving slowly E and expanding its updraft still further.
One thing it did do, before being absorbed by the big bad brute impending, was glow forth an eerie, ghostly layering of light and shadow, interspersed with subtle pastel hues, a weird sight that I’ve seldom seen to this extreme. Back under its SW flank, the near storm developed a circular, slowly rotating, mottled texture to its main updraft region, and even sported a ragged, conical lowering for a short time. What could this storm have done with an extra hour or two before being swallowed by the expanding, ever-intensifying convective Pac-Man stampeding eastward toward us…and it?
The western storm charged onward, turning more deviantly rightward such that its main mesocyclone region — now an HP “stormzilla” with suspicious lowerings in its “notch” area (actual view and deeply enhanced zoom) would go just S of Yuma — while the value or near-forward flank region would absorb our nearby supercell virtually overhead. A short-lived lowering that preceded those photos raised a tight little plume of dust, but due to distance and poor contrast, we’re unsure if it was tornadic.
Though expected, this event still lit a sense of foreboding within, as if billions of icy little swords of Damocles dangled high above. This merging maelstrom of mayhem accelerated too, sure to turn into a destructive tempest of a nastiness and ugliness that we cared not to endure unsheltered. Time to get into town and under that covering!
Surprisingly, we scooted under the canopy of an abandoned drive-in restaurant after only one other car: the county sheriff. Only once the hail began did other vehicles seek room there — most in utter futility. Much as when it was the place to go in Yuma for icy treats of another kind…first-come, first-served! Within ten minutes, hail up to 2 inches in diameter started hammering away on the tin roof, becoming dense in coverage and ear-splitting in loudness. Vehicles that couldn’t fit got a glass-busting, steel-denting beatdown.
Although we had been hailed on while in a vehicle on several occasions, Elke and I hadn’t yet experienced a rip-roaring hailstorm together from under outdoor shelter. It was quality time as a married couple — at least, once I stopped yelling over the deafening din about the camera lens I couldn’t find. We had a blast.
I actually remembered to shoot some video of this with our new HD camcorder (video being something I’m not accustomed to doing after several years without), while also firing off a few hi-res DSLR stills with the lens that turned out to be in my left hand the whole time prior. One of those stills captured the a rare, split-second scene indeed: a hailstone exploding upon striking the pavement. It reminds me of some artist’s conception of an asteroid striking the moon, minus the fireball in the locus of impact.
After the beating was over, we secured a room at a little yellow motel. The lady who ran the motel mentioned that her daughter owned a restaurant and bar in town, Main Event, that was open and serving dinner late. Outstanding…we could avoid the usual storm observer’s conflict between getting dinner before early, small-town closing times and heading out for photography!
We headed a few miles SE of town to examine field hail and photograph the beautiful late-day, post-storm light (looking NE and looking WNW). Here are a few nice examples of that hail, about 45 minutes after it fell (culled from grassy, protected areas):
- Variably opaque core, clear outer layer with numerous radial bubbles
- Same stone silhouetted against the sky to illustrate its translucence
- Different stone, larger opaque core
- Two hailstones: Entirely opaque and rounded, the other asymmetric, broken and of mixed opacity
- Right before the sun sets, four hailstones on a gravel road [Would this compel Lucinda Williams to re-title one of her best-selling songs accordingly?]
While looking down at the hail, don’t forget to look overhead! Upon doing so, we saw sunset-lit fractocumuli shedding condensation vortices, including this ragged funnel and a separate, fishhook-shaped horseshoe vortex that wandered off to the E, slowly spinning down on its own for many minutes in the warming colors of the late-day rays (zoom). Here’s the western sky at the time.
All manner of fascinating processes were happening. Off to the SE rose a skinny, tilted tower, elevated atop the shallow stable layer from the earlier storms, seemed to be divided into two stepwise manifestations of the same convective plumes — one rooted just above the boundary layer, and a second slanted along some higher surface, with a backshear on the W side of the upper layer. Meanwhile, off to our E, dark wisps of scud passed placidly in front of a gorgeously glowing tower in the back side of the MCS. All of this while immersed in the luxuriantly earthy scent of rain-soaked farmland, while western meadowlarks sang from all sides…
We were getting hungry, though; so we cruised back into town for what turned out to be a very good meal at Main Event. I recommend the place for a late dinner if you end up anywhere near Yuma after a chase.
Chugwater Tornadic Supercell
Chugwater WY, 20 Jun 10
SHORT: Observed tornado from second of two supercells E of Chugwater.
LONG: Since Scotts Bluff National Monument was just a few blocks from our motel doorstep, we had time for some late morning through midday hiking, as well as photographing wildflowers and other interesting scenery near the top, before grabbing a quick lunch and heading west to our target area of southeast WY. See, for us, the so-called “storm chase” vacation isn’t just about storms, but about appreciation of as much of the Great plains’ offerings of beauty and wonder, large and small, as possible — storms being the major component, but not the entire experience. And so it was that we strolled atop the bluff o’ tuff, pondering the view up this way from the Oregon Trail’s wagon trains rolling up the North Platte valley below, while also occasionally looking at surface maps and satellite images on our I-Phones, and considering the effect the stable air represented by this stratified overcast would have on the day’s convective potential.
Thin breaks and occasional peeks at the sun indicated some destabilization was occurring, in an area of nicely backed surface winds from there westward, and automated mesoanalyses of CAPE and CINH fields bore that hunch out. As we descended from the hill, as if on cue, the first towers began to erupt over the Laramie Range, where the clouds had been eroded over the highest terrain in the area, allowing maximum heating. We couldn’t see them through the stratus, of course, and I had doubts about how far E convection could make it off the mountains before getting into grunge and weakening There was no doubt we needed to follow Horace Greeley’s old advice and “go west”. As we did so, two storms started to rotate:
-
1. A cell in the Wheatland/Dwyer area, headed NE toward Jay Em but also toward some decidedly stable air, and
2. A storm moving somewhat more slowly and seemingly anchored along the foothills near Chugwater.
We went through Torrington along the way, then SW, catching a brief view of the distant and uninspiring base of the northern storm, before moving SW toward an area of obvious darkness above and beyond the intervening stratus deck. By the time we got to a good vantage W of Yoder and S of veteran WY, the southern storm, which had been a supercell, already was losing definition in its base and soon would turn into a strung-out, most likely elevated plume of convection.
Fortunately, the strong heating continued off the W edge of the stratus deck and the E edge of the mountains, firing additional convection still farther SW. With the boundary layer continuing to get more unstable in that direction, we backed through Yoder and S again past Hawk Springs. Then we then headed up the beautiful bluffs E of Chugwater along one of my favorite drives in the region (WY-313), only to greet an already well-developed and obviously surface-based storm by the time we arose on the high plateau E of I-25. The storm was calving off left splits, one of which can be seen beyond an abandoned farm structure in this shot looking WNW. Turning our attention to the WSW, the large, robust right mover quickly cut a clear slot and formed a broad, rotating, bowl-shaped lowering
behind it (and above the letter “s” ending my name in this wide-angle shot). This was only a few minutes after we had arrived at our location, and then, at 1624 MDT (2224 Z)…
T-TIME!
You see, in most years, a tornado is such a rare and amazing event to witness for any storm observer. This year, I had experienced lousy luck with tornado photography in what has been a banner season for some others. In most cases (e.g., Bowdle SD, Faith SD, Campo CO), I wasn’t available to chase on the fantastic day in question. On one (10 May, OK), I (along with some other very talented chasers) got on the one storm that refused to produce anything more than a brief spinup while observable. On another (16 Jun, SD), the storm blocked the only safe road access to it with flooding and hooks filled with both precip and precip-wrapped tornadoes, while also going nuts on the other side.
After all that tornadic frustration, then, it surely felt good to see one that was not low-contrast, rain-wrapped and/or too brief to photograph, even if it was a small and otherwise not very newsworthy hose. The tornado slowly roamed wide-open land and, to our knowledge, hit no structures of consequence — just the way we like it. As seen from about 3-4 miles to its E, the tornado manifest initially as a tapering cone (zoom), with two episodes of visible ground contact. The first is shown in this zoom (see wide angle structure view), followed by a few minutes where neither condensation nor dust was evident under the base of the funnel (wide angle structure view), followed by a few minutes where full condensation planted again.
That vacillation was described by some observers as separating two tornadoes that occurred from the same vortex (by definition, a tornado must have ground contact), while others deemed it as one tornado with a weak interlude. What is a tornado? The ground was soaked out there, minimizing dust, although it did lose full-condensation again before lofting some combination of spray and dust (super wide, with storm structure). The tornado started to wrap deeply back into its occluding mesocyclone, then roped out.
Tornado-wise, that was all the storm could do. We felt fortunate to get there just in time! We also had to bail east, off the high plateau, because hailstones of 2 inches and larger in diameter started falling around us with discomforting splats and thuds right as I was shooting the last rope-out photo. We got out from under the vault with no hail impacts, then headed S and E in a very difficult effort to find a good W-NW view of the weakening supercell that wasn’t overly obstructed by terrain. Some others we know weren’t so lucky with hail. At that vantage, we encountered the Tempest bunch with Chuck, Chad Cowan, and Bill Reid, here shown calling for lodging from behind two giant hail craters patched with duct tape. Not far to our W, as the tornado began to narrow, that part of the vault immediately downshear from the low-level mesocyclone unceremoniously heaved forth gorilla hailstones up to 4 inches in diameter. It’s a good thing nobody was hurt by that hail (a vastly under-appreciated injury hazard in storm observing)!
The supercell moved over progressively more stable low-level air while attempting to backbuild, and eventually just died. That left us with no storm and some daylight, which we used for traveling to our motel in Sidney. On the way down toward I-90, we stopped to photograph an abandoned farm with soft stratocu and baby-blue sky in the background. We then hopped on the Interstate for a very unusual (for late June!) plunge through a late-afternoon regime of cool fog and mist, in the stratified air mass E of where the supercell had been.