Ice Machine in Yuma, Colorado

August 13, 2010 by · 1 Comment
Filed under: Summary 

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):

  1. Variably opaque core, clear outer layer with numerous radial bubbles
  2. Same stone silhouetted against the sky to illustrate its translucence
  3. Different stone, larger opaque core
  4. Two hailstones: Entirely opaque and rounded, the other asymmetric, broken and of mixed opacity
  5. 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.

Tornadoes, Terrible Traffic and Thunderous Treasure

June 3, 2010 by · 2 Comments
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Loyal/Dover and Prague OK Tornadic Supercells
19 May 10

SHORT: After considerable waffling, targeted the eventual Loyal/Dover HP supercell and saw a couple of tornadoes. Got stuck in the epic traffic jam and left the storm in frustration. Intercepted a photogenic supercell in relative peace and quiet around sunset, near Prague.

LONG:
The Two Chumps, followed by Jack Beven in his rental car, left our lodging in Pampa around 1100 CDT with the notion of intercepting a supercell either along the outflow boundary from the previous night’s convection over central-northern OK, or if it could move into the better moisture and surface winds soon enough, any storm that formed near the dryline/outflow intersection near the OK border with the TX Panhandle. We drove to “Severe” Weatherford, watching the outflow boundary pass overhead and to our N with a gradually deepening and sharpening field of Cu and towering Cu along it and to its S.

A storm fired earlier than expected and farther W, back in relatively dry air with veered warm-sector winds near the border. This wasn’t too appealing to us at this point, so we waited for a spell for closer development near the boundary. We eventually wandered N, catching back up to the boundary as the original storm moved alng the boundary toward us in a rather awkward road network bracketing the Canadian River. Meanwhile, we could see the first deep towers of what would become the Hennessey storm going up 20-30 miles to our NE.

Now what? Faced with this choice, we were mired in an uncharacteristically protracted episode of indecision. Parked NE of Thomas, we sat about equidistant between the older western storm and the newer eastern one, both somewhat in view. We observed the sky, evaluated convective trends and surface data on our Internet connection, and photographed a wonderful little abandoned pumphouse and windmill.

Weather-wise, we just couldn’t decide between one option and the other, hoping for something to erupt in the “best” environment right overhead, even as both storms steadily matured into robust supercells — the eastern one in what seemed to be a better short-term environment, the western likely to struggle some but eventually move into a favorable regime for longer. The vacillation continued in our heads and in our travels for a long time, until the atmosphere forced our hand. Meanwhile we decided to wander NW toward Oakwood, a little closer to the tornado-warned western supercell, but keeping the eastern one in reach. Somewhere in our zigzagging of rural roads in the area, we lost Jack, though he did end up intercepting the western storm independently not far from us.

Meanwhile, we hit a dense deck of stratus and even fog, the temperature outside dropping into the 60s. The air N of this boundary was too cold and stable! S of the boundary, large dew-point depressions prevailed, a recipe for cold outflow development. Furthermore, by the time we got back S of the cold air again, our first view of the storm to the W across the river valley revealed a big but “cold” looking base with towers erupting over the top of what appeared to be a partly modified cold pool. The storm also was accelerating. Bad news!

We decided to get through Watonga and make a dash for the storm approaching Hennessey. Alas, it too accelerated, but away from us, tornado warnings and even reports starting to stream in over the TV simulcast on our vehicle radio. Damn, we thought…would we miss the show today? Glances back at the western storm indicated less stratified and more unstable structure, and it was moving toward the area just to our N.

Our decision had been made for us, so we ended the waffling and headed N past Omega to get in the western storm’s path again. As we headed N toward the optimal easterly escape position on the familiar E-W road through Loyal (a venue for tornado success on 4 October 1998), the supercell churned east toward us at disturbing speed, revealing itself as an HP “Stormzilla”.

It was assuring that we had a dependable east road, at least until it stopped at a T-intersection WSW of Dover, when where knew we would have to dive S. With an uncomfortably zesty component of forward-propagation, we couldn’t stay in any one spot long to observe and photograph the beast. The only realistic chance to see any tornadoes it would produce would be from about our latitude, E to ENE of the HP mesocyclone and NE of the onrushing drum of heavy rain and hail.

Sure enough, as we stopped alongside Bobby Prentice and Gene Rhoden 1 mile E of Loyal, a small but unmistakable tornado formed in the rain to a few miles our W. In a Keystone Kops moment, fumbling around for a zoom lens in a new photographic vest that I unknowingly wore inside-out and backward, I missed capturing the best ground contact of condensation, shortly after this shot at 1734. Fortunately Rich had just one lens with which to fumble, and snapped a shot at the right time. The irony was that my 200 mm zoom lens (for the only time ever) couldn’t reconcile itself with the camera, and the viewfinder settings somehow didn’t match what actually was shooting — by 3 stops or more! I hadn’t experienced this before, nor with numerous shots using the same lens since. Go figure. The zooms were underexposed crap, and I quickly reattached the 24-70 mm L-series glass.

By that time (1736), the tornado was vanishing in a major mesocyclonic wrap-up of rapidly rotating clouds and precip, and we had to go back E to stay ahead of the surge. As we headed S, 4 SW of Dover, we peered into the gorgeously turquoise-capped murk of rotating HP mess a few miles to our WSW and spotted another tornado. As we ran up an embankment to shoot, the curtains parted to reveal a fat cone with multiple vortices whipping around its base (time 1751, estimated tornado location 4 SE of Oneida). This was an eerie and beautiful sight, but with the mesocyclone now right-moving toward the ESE and us needing to get out of its way, we knew we couldn’t sit there sipping mango Slurpees and listening to Jimmy Buffett songs. A few more shots, including this wide-angle (can you spot the tornado?), and it was time to bail S.

Unfortunately, we took a little too long and got stuck behind a local lady whom we couldn’t safely pass, driving 40-50 mph in her pickup. She didn’t seem to grasp the urgency of the situation. We also inaccurately assessed the distance of the rain-wrapped tornado and the speed of translational motion, such that when we drove S through the E side of the precip, the tornado’s bottom unexpectedly appeared as a ferociously spinning cage of precip and condensation in the field about 300 yards to our W. Not cool. Rich was able to peer up at the funnel heading our way at a barely beatable pace. Fortunately, he gave a blow-by-blow update of its position as we scooted out of the way, letting the vortex cross the road just behind us. This was a definite misjudgment on our part, which certainly didn’t help our mood in what was about to take place.

Relieved to get out of that whirling cauldron, we headed E on a paved road 3 N of Kingfisher in order to get ahead of the storm while avoiding the traffic delays of the town, stopping quickly to look back at the deeply rain-wrapped supercell now off to our NW. Turning S to go to OK-33, we suddenly found ourselves one amongst many, many vehicles in a miles-long strand of brake lights and antennae, extending over the next hill, the one after, the one after, and the visible horizon.

I’m not talking about tens, or dozens, but hundreds, perhaps thousands of vehicles. Yes, we were part of the problem — if there were 2,000 cars, we were 1/2000 of the horde. I’ve got extensive experience on the streets and freeways of Dallas and Miami, and have seen the worst that their traffic snarls have to offer. After this, I rather would sit for four hours on a hot day in the parking lot of Central Expressway or Florida-836 than endure what happened on OK-33 again. Even with the great majority of these near-storm watchers behaving themselves, this was the most intensely stressful driving situation I’ve ever been involved with. Imagine mile after mile of vehicles in a long train on two-lane country roads, all moving at the speed of the slowest (around 40-45 mph on average) with a certifiably tornadic HP supercell bearing down hard. We already had been involved with one close call of our own doing, and wanted no part of another caused by a traffic jam.

At one point, while waiting behind a 30-40 vehicle line to turn left at a stop sign (onto OK-33, which also was jam-packed), a chase-yahoo behind us pulled into the left (oncoming) lane, raced past the line of cars up to the corner, ran the stop sign, drove in the oncoming (westbound) lane of OK-33, then jammed himself into a gap in that traffic about a quarter mile E of the intersection. This person thinks his life and car are more important than everybody else’s, and needs to be taught otherwise. [Only later did we find out about some wantonly dangerous behavior earlier in the afternoon by a separate “team” of chasers affiliated with a Discovery Channel production.] Yes, I was and remain angry about this. No TV footage or storm video is worth endangering innocent lives! Somewhere in hell I hope there’s a special slow-roasting pit set aside for selfish little cowards like that, and all who share such a mentality.

Even though all others we saw in the huge traffic jam were more civilized, we were absolutely and completely at the mercy of the everyone else out there, and it was time to bail out of this asphyxiating and dangerous crowd. At one point near Guthrie, we caught a glimpse of the circulation that produced the last visible funnel with that storm, but we had enough of the circus and headed S on OK-74 and away from the supercell. It’s the first time I’ve ever left a tornadic supercell, on purpose, because of the presence of too many other people.

Initially hoping to get ahead of the messy supercell headed for areas just S of Norman, we headed E on the Kilpatrick and Turner Turnpikes, gaining great time, then S on 177. Instead, we slowed down a little to let a small but tornado-warned storm pass across the road to our S, then drove down through Jacktown, right behind the back edge of this most interesting supercell located between Meeker and Aydelotte. Through thin veils of precip wrapping around the NW side of its hook, we easily could see its rotating wall cloud to the SE. This was an unusual vantage of the business end of a supercell, given both the direction of view, and the dense crosstimbers that characterize most of the area E of OKC. Conveniently, a crew with the local fire department and county emergency management pulled up, so I explained to them what was going on, they radioed the news up the chain, and we watched the mesocyclone pull NEward to our SE and E for a spell.

Meanwhile, the clouds to our W opened just for a minute, casting a dazzling portal of late-afternoon sunlight over the landscape and a brilliant rainbow across the supercell to our E, still sporting a visibly rotating wall cloud through translucent precip curtains. This wide-angle view, pretty as it is, doesn’t do the scene justice. In the distance, below and behind the wall cloud, behold the CB for another tornado-warned supercell, located over far eastern Oklahoma. In the face of this kinds of atmospheric grandeur and beauty, all my tension from earlier simply wafted off on the rain-cooled breezes. It was as if another chase day was born, and a fresh opportunity for immersion in amazement of natural wonder had been set on our table.

Newly energized for one final intercept run of the day, we headed S and I on I-40, stopping for a piss break and an occasional look at the sculpted storm to our N in the fading daylight. An obvious mesocyclone with several suspicious lowerings appeared, then cut a pronounced clear slot while apparently consolidating its area of storm-scale rotation. This may have been the tornado reported 6 W of Prague at 2015 ( enhanced crop-n-zoom), especially if the report time was 4 minutes late (shot at 2011). It was in the right part of the storm — a matured occlusion area — and its apparent position, relative to ours at the time, matches the location of the report well.

That mesocyclone weakened and a precip surge to its NE obscured the new mesocyclone with more HP character. We watched it pass to our N from the North Canadian River bridge area on US-377, then returned to Norman, tired and spent, and ready for rest after one of the strangest and most draining chase days ever.

Pokin’ to Punkin Center

July 4, 2009 by · Comments Off on Pokin’ to Punkin Center
Filed under: Summary 

12 Jun 9
Punkin Center, CO

SHORT: Observed a couple hours of a high based, outflow-ish supercell in east CO. Heard later about weak nocturnal tornado that hit our property back in Norman.

LONG:
Too far from the central OK target area after our PUB-LAA chase the previous evening, we let others play that. Instead we decided to head toward my in-laws’ place outside DEN to position ourselves for weekend chase potential nearer to there. If we saw Palmer Divide storms along the way…great!

We stopped to photograph the abandoned 1899 Star School W of LAA (window shot), and spent a couple hours exploring and doing photography at Bent’s Fort (to be posted later). From there we cruised N out of Ordway toward the projected path of a small young supercell that had formed along the Palmer Ridge SE of DEN. When we let the storm pass to our N and then to our NE, at Punkin Center, it blasted us with a cold, wet RFD — one that surged well S and SE of the main updraft region. We played with that high based storm for a couple hours as it moved slowly ESE past US-287, observing intermittent wall clouds and a couple of cold outflow surges. Mostly the storm was rather high based and featureless while we were on it, and was surfing above its own outflow.

My chase desires gave way to my wish to be a good husband, so we broke off and headed to nearby DEN to see Elke’s mom. Along the way we got a fine rainbow 8 SE of LIC (17 mm wide-angle, and on the other extreme, 600 mm zoom), a CG barrage along I-70 from elevated storms near Bennett (no photos), and some non-critical but needed automotive maintenance slated for the following day.

It was shortly after we arrived that I found out about the supercell that has sprung up over Norman and quickly produced a tornado…which passed over my house. I’ve written about that entertaining saga in a Weather or Not BLOG entry!

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