Last Chance near Last Chance
Wiggins to Cope CO
23 Jun 13
SHORT: Remained ahead of northeast CO convection as it metamorphosed from early, fuzzy slop near Hoyt and Wiggins to a supercell-infused squall line between Woodrow and Cope with several photogenic and beautiful scenes.
Final chase days of the season usually are known in advance to us, because we tend to take our Great Plains trips near the end of the traditional spring storm-observing season in a fixed time slot. As such, many last-chance chase days are known as such that morning, if not before. They can get sentimental. We focus and reflect on the possibilities with a renewed sense of wonder and anticipation, knowing this is the final opportunity for the season and probably the year (save the opportunistic fall chase that happens once every five years or so).
Northeastern Colorado was the target area, with the old outflow boundary from the previous day’s convection in WY and NEb having settled southward into eastern CO and weakened, leaving behind some upslope flow into the Front Range, reduced low-level moisture compared to the previous day in WY, and weaker (but still sufficient) shear for supercells. Cloud bases were likely to be high, with strong potential for outflow dominance and meager, conditional tornado risk.
Yet these reduced-moisture, upslope-flow days often yield scenic skyscapes festooned with interesting storm clouds of various types–especially if one is patient with often ragged, nebulous early convection and keeps apace until it organizes. Forecast storm motion toward the CO/KS border area also likely would take us toward I-70 and a one-day drive home the following day.
Our weather-dictated itinerary the previous several days had taken us from MT-ND-SD-WY-NEb, where we were starting the morning in Kimball, right by the CO border. It was as if a storm-intercept guide had been navigating us gradually homeward with amazing skies and fantastic experiences all along the journey. How fortunate! And here we were, ready to partake of one more afternoon of beautiful storms on the way home.
Proximity to the target area allowed plenty of time to eat brunch, analyze data, and watch the southwestern horizons. Early-afternoon towers erupting to our SW, in northern CO, were easy to see from IBM, so we cruised easily S to Ft. Morgan and saw the high, fuzzy bases even from there. Continuing SW through Wiggins toward Hoyt, we got a nice close-up view of the virga factories, appreciating the majesty of the High Plains even under soft storms, on scales large and small. Small? Oh yes. We enjoyed watching birds that Elke couldn’t identify hop through the stubbled cornfields of 2012, skittering along at a deliberate clip, pecking away at bugs, seeds, or other material unseen.
Next, we retraced the path back up to Ft. Morgan, then veered southward to get on proper road options that would allow us to stay ahead of whatever would evolve from the growing multicell complex to our W. While doing so, the convection slowly acquired visible, if still high, updraft bases, which gradually grew in areal extent and number along with CG flashes. I’ve seen this before. Usually, in these favorable deep-shear profiles, a supercell will develop unless the entire mass is blasted asunder in infancy by cold outflow. That wasn’t happening; the cores offered only feeble density currents, judging by the lack of proximal dust plumes.
Jaunting off the main highway between Brush and Woodrow, a couple miles down a dead-end dirt road, we found a good place right at the terminus where we could photograph wild sunflowers and a wild storm. Cores grew. Updrafts grew in front of the cores. Inflow strengthened. The whole raggedly beautiful storm pile got better-organized and backbuilt before our very eyes, ears and nostrils, as revealed during a stop just S of Woodrow.
East on US-36 4 miles out of Last Chance, and another mile N on a (barely) paved side road, led us to temporary solitude: us, a photogenic abandoned farmstead and the rampart of storms in the west. Whoa! What’s that back there to the NW behind the old house? You guessed it, brother–not just an old storage building, but a high-based wall cloud and mesocyclone.
Although short-lived, the line-embedded supercell provided some striking, picturesque scenery as it headed ENE, before getting disorganized in favor of other updrafts to our own W and SW. While watching that spectacle, a ranch mom and her kids drove up on an ATV to make sure we were OK; we chatted with them awhile before one of the little ones drove them all back to their house on the four-wheeler. Encroaching storms sent us eastward to the Anton area.
Even though the whole complex was becoming increasingly outflow-dominant in the fading daylight, a marvelous episode of deep twilight blues, slate to marine in hue, sandwiched layers of laminar cloud material to the SW…to the N…to the SW again. What a show! At least transiently intense, somewhat supercellular updrafts kept forming along its leading edge, with assorted notches (some rather sparkly!) and other circulations of varying scales.
Admiring the scene, we also noticed that the base surfing outflow to our SW was becoming increasingly circular, quickly. Within less than 30 seconds, and about a mile away (closer than it appears in this wide-angle shot), a small but tightly rotating wall cloud formed from a pre-existing, seemingly benign lowering under that base (annotated version). Quickly, dust stopped then rose beneath. The circulation started to hook toward its NE–right at us. What had been light westerly (but mild) outflow winds backed and accelerated from the ESE. Time to bail out of there!
Although I doubted any substantial tornado could develop in this circumstance, I didn’t want to be the guinea pig to test that hypothesis. Even though we only had to go less than 1/4 mile to get back on US-36 and gun it eastward, we still were not comfortably relaxed–no thoughts of rocking in hammocks beneath Caribbean tiki huts while sipping dewy beverages. Instead, the rising pile of dust, under a small area of cloud-base rotation, with screaming inflow winds, nearly overtook us. I can’t say for certain if that circulation ever tightened into a full-fledged tornado, but if not, it came precariously close.
Just as fast as it formed, deeper outflow from the west crashed through the feature and tore it up, leaving behind a dispersive dust pall over the highway behind us as we gained a few miles of headway. With daylight fading fast and eyelids growing heavier, we watched the mess become more linear and turned S toward I-70, out of the way of all storms. A night at our favorite motel in ITR, lightning flickering off to the N and NE, closed out our 2014 storm-intercept season with a lullaby after the atmosphere’s final flourish.
Driving home the next day, we reflected and remembered. What a season it was…rewarding for us photographically, educationally and spiritually through the unfailingly transcendent experience of wonder and awe before storm-tossed Great Plains skies. The sting of major missed tornado events practically in our backyard was healed during over half an hour of observing from one spot a nearly stationary, violent, yet ultimately harmless tornado in open country of northern Kansas. We made some great memories amidst the solitude of the prairies from North Texas to central Montana. With heavy hearts, we also thought of old friends killed just over three weeks prior by the vaporous forms we seek, on a day when we didn’t head out. Here’s to a safer and much less destructive, yet more photogenic and inspiring, 2014 storm season to come.
Our PING trail for this day. [PING date is ending date in UTC.]