Bighorns Boomers

January 2, 2014 by · Comments Off on Bighorns Boomers
Filed under: Summary 

Bighorn Mountains, WY
17 Jun 13

SHORT: Two rounds of morning to midday storms in beautiful Bighorn Mtns., rain from weak/dying convection WY/MT border.

LONG:

Today was intended to be a leisurely trek from Buffalo WY to MT, but not by the Interstate. Instead we had all day, thanks to a lack of substantial severe-storm potential until day-2 in central MT. As such, we aimed for a reunion with the Cloud Peak Skyway and its resplendent vistas of the Bighorn Mountains, followed by a trip across the Bighorn Basin to a stop somewhere in south-central MT for the night. We weren’t planning on a storm chase and didn’t have one, per se.

Yet storms found us–and in one of the most scenic of places. A line of elevated thunderstorms rolled through the mountains in mid-late morning. This unusually encountered but most welcomed situation offered forenoon storm-light, and very interesting backgrounds for wildflower-landscape photography that ranged from eerily brooding closeups to deeply textured, pastoral meadow scenes one might better expect in the Austrian Alps. Given Elke’s heritage from the latter area, is it any wonder that she so wondrously appreciates the June wildflower show in the Bighorns?

Adding to our gallery from 2007, we also focused up-close on some gorgeous floral displays, whether from just the ubiquitous lupines, lupines with arrowleaf balsamroot, smoke towers–towers of prairie smoke flowers that is, Nelson’s larkspur (a highly toxic plant belying its beauty), mountain goldenbanner, a variety of false dandelion, or the common white locoweed that is the bane of western stockmen. We even saw a double puff of smoke!

Round one of storms passed quickly and harmlessly NE of the Cloud peak area by midday, however it left behind two prime ingredients for further convective development in a weakly capped, high-country lift regime: an outflow boundary and moisture–each of which were cooked in sunshine at ten thousand feet. Duly primed, additional deep convection began towering upward throughout the central and southern Bighorns, including overhead. Safety considerations (don’t want the first lightning strike to zap one’s noggin) and lunchtime hunger prompted us to evacuate the high country and head toward the basin, whereupon we took one final look back at a now storm-blanketed range.

Late lunch in Worland (which was pretty good) preceded a trek NNW toward Montana, through Greybull and Lovell WY. This part of the basin is desolate, with a great deal of bare, rocky ground and salt deposits. That’s related to the very dry climate, a result of being surrounded by mountain ranges with only a small gap in the north. Even that small gap sometimes lets low-level moisture creep in; so the vegetation got a little greener as we cruised out of Lovell toward the MT border. An expansive area of mostly orphaned anvil wafted overhead from some earlier storms in the Absaroka Mountains to our W, dropping a light, gentle rain on us as we crossed the border. What a peculiar novelty this was!

Rain in such a dessicated area often cools the air a lot evaporatively and leads to a rich, earthy aroma, and this was no exception. We welcomed both as Montana welcomed us. We enjoyed the views of the Bighorn River from the highway, called in motel reservations in Roundup for the night, bought a road atlas at the Billings Barnes and Noble outlet, got a late dinner in Roundup, and settled in for the night…anticipating our first central MT chase day ahead. This northern Plains trek already had been richly rewarding, and the following day would pile on that reward with a good dose of adventure!

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Our PING trail for this day.

Pleasant Diagonal across North Dakota

August 19, 2012 by · Comments Off on Pleasant Diagonal across North Dakota
Filed under: Summary 

Rolla and Grafton ND areas
9 Jun 12

SHORT: Small convective towers and beautiful sunset Cb photographed along with abandoned structures and Northern Plains landscape.

LONG: This date loomed several days in advance, even in national forecast outlooks, as not just a potential supercell day, but tornado-outbreak day, across the eastern Dakotas. As time got closer, it became more and more apparent that the wind fields would be there–albeit in a smaller area mostly encompassing eastern North Dakota–but lack of robust moisture would be a major hindrance to storm development. So would capping, for much of the day, despite strong large-scale and frontogenetic forcing.

Elke and I had an additional logistic quandary in that the best low-level shear would be N of the Canadian border. We wouldn’t mind chasing there; but we didn’t bring our passports. So we undertook a strategy that, in essence, was: get ahead of the cold front and tuck ourselves just S of the border to jump on any storms that might develop to our S and mature before crossing the 49th parallel.

I was rather surprised to see the number of Southern Plains storm observers via SpotterNetwork attempting the long and dangerously sleep-deprived overnight trek from Oklahoma, Kansas and even Texas, for what looked to me like an ever more feeble setup for tornadoes. By contrast, we already were in the region and on vacation, with no particular place to be for a few days after the system departed. In fact, we fully intended to stay in ND after this day, until the next northern-stream weatehr system, and explore the state. North Dakota seldom was visited by us before now, and never in-depth, as true appreciation warrants. We had wanted to spend more than a couple of days in ND for many years, and now was the start of that chance!

Originating our trek from Bowman, in the SW corner of ND, involved an earlier-than-usual arousal from bed and crisscrossing the state on a diagonal. Fortunately, ND is not a particularly massive block of land (similar in area to Oklahoma), and the roads are plentiful and in good condition E and N of the Missouri River. Some short-range, convection-resolving models unzipped the front N-S across the eastern third of the state by about 4-5 p.m.; but I didn’t buy it. A simple examination of the 700- and 500-mb charts, surface chart and moisture-channel imagery indicated the strongest lift might not even occur before dark; and supercell initiation would be improbable before 0Z. For once, I was confident early development would not be a problem and storms would hold off before late afternoon, enabling a stop in BIS for lunch and procurement of a much-needed ND road atlas. [Yes, we still navigate chases exclusively with paper road atlases, though we found the BIS Barnes & Noble with I-Phone Google Maps–the best of both worlds!]

We zigzagged NNE from BIS through Rugby, stopping to visit the geographic center of North America. While heading E to stay ahead of the bent-back portion of the cold front, we crossed an outflow boundary from a strong morning MCS that was, in effect, acting as a warm front. Clouds on the NE side of the boundary were scuddy and more stratified than on the warm (SW) side that overtook us several minutes later. As the boundary crossed our location, we noticed that blades in the eastern portion of a nearby wind farm still were facing SE on the cool side, whereas those in the western part had pivoted to face S–a modern manifestation of “reading the wind”. Although those towers near the boundary were unlikely to build into a mature supercell before reaching the border, we had hopes others could fire farther S on the front and move our way.

Meanwhile, we stopped a few times between Rugby and Rolla to pass the time–enjoying the scenery of the Northern Plains‘ post-glacial landscape (closer shot of gaillardias with bumblebees) and that bit of Americana involving an old barn with glacial rocks. As seen from a spot near Rolla, as far N as we ever had been on a chase, convective towers kept bubbling along and ahead of the front to our W, but neither broadening nor deepening appreciably until crossing into Canada. Even then, they didn’t survive long upon crossing the remains of the outflow boundary.

Regarding the day as an increasingly probable bustola for sustained storms, but still wishing to stay ahead of the front, we headed several more miles E into Towner County. It was nearly 8 p.m., still plenty of (low) daylight left, and a few towers were erupting to our distant SE. Those appeared to be along the remnants of the outflow boundary, and a quick glance at a surface map confirmed that. But they also were on a sharply defined confluence line and the E edge of strengthening N-S baroclinic gradient ahead of where I thought the forward segment of the front should be by pure extrapolation of translation. The front was redeveloping (frontogenesis) ahead of its previous position–in effect, jumping E of us!

Zooming E on US-281 and ND-5, we realized that the first cell was moving fast and would pass our longitude before we safely could get there; it became a short-lived supercell just into Manitoba, N of the dying old outflow boundary. When realizing the futility of that pursuit, we stopped to photograph an abandoned farmhouse and barn in the warm, late-day light, with other frontal towers across the background skyline.

More cells fired to our SSE, this time reachable. However, since it would be just a little before sunset by the time we would intercept them along the now eastward-accelerating front, we chose to hold back W a little and photograph them from the side preferentially aglow. By the time we reached a point near Hoople (between Cavalier and Grafton), scuddy low clouds broke enough to afford us great viewing of the spectacle. As the sun set in the NW, a small cumulonimbus just past the Minnesota border reflected brilliantly in the eastern sky, turning deeper shades of peach and apricot before falling into shadow and growing dim. The convection softened, weakened and moved away rapidly after sunset, which was quite late in those parts (9:52 p.m. at our filming location); so we headed to nearby Grafton for lodging and a late fast-food dinner.

Elke and I had started the previous day in Cheyenne, WY, and ended it here in northeastern ND. That’s a long haul! Yet we had undertaken a scenic and rewarding trip, bisecting the central and northern Plains from SW-NE. The journey hadn’t been quite as tiresome as the many miles might make it seem, probably thanks to the many stops and small rewards bountifully scattered along the way. Still, we were ready for a few days of post-frontal rest and relaxation before the next storm-spawning system. I didn’t count on a fortuitous encounter with photogenic cold-core storms the next day…