A Championship Day (Even if Not for Storms)
High-based Storms in the Nebraska Panhandle
12 June 11
SHORT: From LBL, headed to the BFF area for high-based upslope action. Observed a few such storms from between BFF-AIA.
LONG:
The day wasn’t too spectacular convectively, but we saw storms and had a great time nonetheless.
Morning dawned to the analytic display of foci that were somewhere between muddy, nebulous and vague on the spectrum of precision. The surface map showed that the isodrosothermal field had been mangled by overnight and morning convection over southern Kansas, east of where we spent the night. When all else fails, the terrain just isn’t going anywhere–at least not for the next 20-30 million years or so.
We therefore headed toward the reachable area of the NEb Panhandle/NE CO, figuring that 50s F dew points in that area sometimes do good things as long as deep-layer shear is at least marginal. It also put us in position for day-2. Plus, Elke and I love that area for many nonconvective reasons.
After visiting an abandoned shack in western KS, we found a nice hilltop vantage about 5 SW Angora NEb, listening to assorted birds and photographing wildflowers (e.g., copper mallow, western wallflower, and veiny dock), as we waited for convective eruptions.
Assorted towers and turrets soon bubbled up to the W and SW. One persistent pile to our W evolved into a short-lived, high-based storm with a wall cloud to our NW, viewed across the rippled orographic musculature of the Nebraska Panhandle’s ash-bed grasslands. The storm exhibited weak cyclonic shear in the midlevels based on radar velocity output, but just for a few scans.
Other, smaller, junkier cells fired along the foothills in SE WY and over the western reaches of the Wildcat Hills to our SW, amounting to little except as a scenic diversion for aviators. We saw several contrails weaving between storms, including this scene over Minatare. The storms died off with the setting sun.
We settled into a charming little mom-n-pop motel in BFF with funky walls made of green quartzite from Utah. This also was the memorable night my hometown Dallas Mavericks won the NBA championship too–making up for a disappointing evening 5 years before in GCK when I watched them lose it to the very same team.
A very fine day, indeed…
2010 Chase Season Dénouement
22 Jun 2010
Southeast WY to North Platte NEb
SHORT: Outflow-dominant supercell observed twice — once in SE WY and another in NEb Panhandle. Gorgeous sunset supercell S of Paxton NEb.
LONG: We were hoping for one final photogenic supercell for our chase vacation, and instead got two.
A piping hot lunch at a local cafe in downtown Sidney NEb, featuring a platter of smashed and fried Rocky Mountain oysters, settled down hunger’s restlessness just long enough for us to watch satellite imagery on the mobile phone, seeking first signs of convective initiation on the Laramie Range to our W. This area would experience favorable upslope flow, decent low-level shear and deep-layer winds, along with sustained surface heating in the absence of any appreciable, antecedent cloud cover, but moisture seemed a tad on the scant side. Once the first towers started to fire NW of CYS, we hopped onto I-80 and roared westward.
By the time we got to Pine Bluffs WY, deep towers were visible with glaciation to our NW. We could see the cloud bases easily, so we fueled at a truck stop there as I chugged down a cold, delicious A&W float. I also reserved a room in LBF for the night using a combination of forecast storm motion and positioning needed to go back home the next day, while watching for a storm to congeal and organize from the agitated area. Soon, it did, and we took off W through Burns and then N, retracing in reverse a segment of our chase path from the tornadic Chugwater event two days prior.
True to the lack of more robust moisture, the bases seemed uncomfortably high, and I was troubled further by how fast the cells started moving E off the mountains as we approached. Was the convection already spewing outflow? Yes! We barely beat the storm to the intersection of WY-213 and WY-216 W of Albin, near which I shot this photo looking W. Yes, there were updraft bases all right, but they were being undercut very quickly by wickedly cold currents hurtling SE from the precip cores. We headed E on 216 to Albin, having to make a decision there either to:
-
1. Take unpaved back roads and stay closer to an outflow-surfing wind and ice machine, risking its outrunning us for good somewhere not far E of the WY-NEb border, or
2. Shoot back down to I-90 and bust eastward at higher legal speeds so we could stay abeam and eventually get back ahead of the storm on a north road.
Although I’ve seldom seen such an outflow-dominant storm recover to produce tornadoes, it has happened on one occasion. Furthermore, such storms can produce interesting and sometimes beautiful cloud formations, especially out on the high plains. The decision was easy.
Meanwhile, before zooming down to the Interstate, we watched the storm cross the road to our N, spying a suspicious-looking but very short-lived formation buried in a mesocyclonic notch region (enhanced crop-n-zoom of previous image). That feature quickly vanished, and the whole messy and wild-looking process roared past.
By the time we got just the few miles S to I-80, the storm already had gotten well off to the NE, brilliantly festooning a deep blue sky (wide-angle view from I-90 near the border), with a high and ragged base visible on the trailing flank. That, along with the main updraft base of the storm to our left, were visible as we cruised E to Sidney, then N toward Gurley — in the process retracing a late-day segment of our trek from the previous season’s intercept of the LaGrange WY supercell. For our nearly continuous view of the updraft while driving, and several chasers who were closer at that time and didn’t see any tornado, I had to question the “sheriffnado” reports just E of the border in NEb.
We got directly ahead of the storm again E of Gurley, watching its somewhat-lower base with a small, shallow wall cloud developing to our WNW (wide-angle view) while a deck of low clouds formed overhead. The storm itself was decelerating markedly, and its own outflow boundary appeared to outrun its main reflectivity area (and mesocyclone aloft). I got a dread that the supercell wouldn’t last much longer; and it certainly did not. A zoom view shows the wall cloud that was surrounded by translucent precip. Within minutes, a fuzzy gray bowl of precip appeared right in and under the wall cloud, descending and expanding and obliterating the wall cloud as it reached the ground, and making a splendid example of a tornado look-alike.
Was this a descending reflectivity core (DRC) that came down in a very deleterious place for any low-level mesocyclone’s development and survival? It sure seemed as such. Here’s the view 3 minutes later, when the precip core further expanded and utterly obliterated the cloud base where the wall cloud previously had dangled. Within 11 minutes more, the outflow had gone past, the low clouds cleared away to reveal an astonishingly rapid storm demise!
Thinking that was it for our chase season, we headed E toward LBF, only to see a stunning and spectacular convective eruption to our SE, S of Paxton, beneath a waxing gibbous moon and shortly before sunset. As this storm evolved into a short-lived supercell, we admired the amazing spectacle from a corn field a couple of miles S of the Interstate, until an inverse relationship between amount of sunlight and mosquitoes hastened our resumption of the trip. What a wonderful way to close out the last chase of Spring 2010!
When we settled into our room in LBF, the clerk remembered my call and said we were smart to do what we did many hours before; all the rooms in LBF were booked up solid! After 11 p.m., we noticed a dramatic increase in lightning to our N-W, as storms erupted along the outflow boundary. While cruising S of town in search of a good vantage in that direction, the storms weakened again, precluding any decent lightning photo opportunities, though we did salvage a nice look at lunar crepusculars around an altocumulus deck.
This was a rewarding day, one that left us in ideal geographic position to do something we had wanted for a long time: pick up a stone fencepost from one of the quarries near RSL. It would be right along the way home the following day. Our adventure in doing so was a marvelous glimpse of Americana, chronicled in more detail in this BLOG entry. The dénouement had been written on our chase season – one that was, at times, agonizingly frustrating, and at others, as fulfilling as can be. What adventures await in 2011?
Birthday Supercells in Northwest Nebraska
near Harrison, NE, 21 May 10
SHORT: Intercepted 4 supercells, 2 after dark, near Harrison NEb, with 2 funnels from twilight storm S of Harrison.
LONG:
My two main forecast areas on this day were in eastern Colorado, for any storms that could form and move ENE off the Front Range or eastward-extending ridges (Palmer and Cheyenne), and of course the classical upslope play into the Laramie Mountains. Since I began the day in Russell, the CO target was much closer, and more probable to reach by convective eruption time. The idea was to pass through, and if it looked dead, continue onward into SE Wyoming or Nebraska.
Unfortunately I got stuck at a long construction delay between Burlington and Wray, where US-385 is down to one lane with a pilot car driving 15-25 mph for about that many total miles. After getting out of that horrendous mess, I thought my Wyoming/Nebraska hopes were ruined, so I photographed an abandoned farmstead for a bit S of AKO, while waiting for storms to fire in northeast Colorado. The air mass kept looking too stable and stratified, and I gave up once storms E of the Laramie Range began to sustain themselves.
Unfortunately, because of the long intervening distance needed to intercept the resulting supercell, I never made it to the Wyoming phase of its life cycle, when the structure was best. Instead I cruised N from Mitchell on NE-29 to get ahead of the storm, knowing it would be moving into gradually more stable air. A portion of the legitimately scientific V.O.R.T.EX.-2 fleet came up 29 right behind me, along with some pseudo-scientific vehicle with a bogus-looking “TORNADO AND HURRICANE RESEARCH” sticker prominently plastered thereupon. I felt like stopping to ask the “TORNADO AND HURRICANE RESEARCH” crew what papers they’ve published with their “RESEARCH”, but knew the answer, and more importantly, had better things to do — namely, observe the supercell.
Lightning activity above me, in the anvil, was increasing, so I got back in my vehicle. Not a minute after I did, I happened to spot a CG hit within less then 50 feet of that “RESEARCH” vehicle, and about half a mile downhill from me! It even looked like the lightning might have hit them. I started the truck and was throwing it into gear to rush to their aid, when they abruptly pulled out of their spot and zoomed southward past me. It was a very fortunate thing none of them got struck! One of these days, however, under less atmospheric duress, I intend to query such crews in the field and find out about the nature of their “RESEARCH” publications. Anyway…
This shot fairly well represents my view of the old Torrington storm as it scooted across the border into Nebraska. At times it did develop weakly rotating, scuddy wall clouds, but its encroachment upon more stable air yielded the expected result with time ( here shown as a higher, flatter wall cloud with precip-filled occlusion-downdraft slot, behind a sticknet). That storm moved N and NE of me, and I prepared to head to Harrison to look for lodging.
Meanwhile, I parked for a spell to listen to the cheerful choruses of western meadowlarks and breathe the refreshingly rain-cooled High Plains air behind the first storm. V2 left the area, and in the twilight, a new, small supercell formed along or just a shade N of the outflow from the other one, SW of Harrison and about 15 miles to my WNW.
Rather quickly, some cloud-base rotation and lowerings developed under a broad, elongated updraft area, followed in quick succession by a skinny, scuddy funnel (deeply enhanced crop-n-zoom) and then a lower, more robust-looking and separate funnel (enhanced crop-n-zoom). Both of those funnels were quite transient, and I could not detect any dust or debris at the level of the (wet) ground beneath. If either was a brief tornado, it was too weak and short-lived to count as such, so I probably still haven’t seen a tornado on my birthday. Still, I’m glad to have had the experience.
The twilight supercell moved too deeply into rain-cooled air left behind by the first, and weakened considerably. I got a room at the only motel in Harrison — the Sage Motel, a friendly if rather forlorn and cramped place — and called Elke and my kids. One highlight of the day was my daughter and her friends singing “Happy Birthday” to me as a quartet serenade!
Meanwhile, two new supercells popped up in Wyoming, SW of town, headed that way! After getting off the phone, I wandered a few miles W of town to watch the nocturnal supercell pair move quickly past, their structures faintly illuminated at times by in-cloud lightning. I attempted photography, but it was just too dark out there, the lightning too faint. The rear-flank precip core of the second storm hit Harrison, but without severe wind or hail.
I had to be in Denver the following night to meet Elke and prepare for her mom’s public memorial on Sunday the 22nd, so the potential (and realized!) major tornado day in northeastern SD was too far for me to chase. Instead, on the 22nd, I photographed morning fog in the Pine Ridge area N of town, then drove from Harrison to DEN, stopping for a pleasant hike and photography excursion Agate Fossil Beds National Monument along the way. Meanwhile the ultimate tornado-feast was about to begin for other chasers 250-300 miles to my NE.