Altus Night Lightning

January 27, 2015 by · Comments Off on Altus Night Lightning
Filed under: Summary 

Altus OK
26 Apr 14

SHORT: Weak diurnal storms NW TX, brief supercell with lightning burst near LTS.

Elke and I were off on this day, so we decided to go for a country drive to enjoy a fine Saturday afternoon and evening. That country drive involved heading SW from Norman, specifically to the warm sector ahead of the dryline near Vernon.

Because of a lack of richer moisture, prospects for anything tornadic didn’t look promising, unless a ribbon of higher mixing ratios could arrive just in time for that “magic window” of evening hours, when the boundary layer starts to decouple but the surface parcels still may be available to storm inflow. That scenario appears in wishes more than in reality in springtime regimes involving early-stage or incomplete moisture return, so we simply headed out in hopes of seeing some photogenic convection.

Wandering some backroads S of Vernon, we saw several nondescript cells bubble up and down in a SSW-NNE-oriented train. Most appeared rather mushy, befitting the lack of more intense CAPE, and didn’t exhibit any structure that compelled me to take more than a few test shots to make sure the camera was working. Still, we found a couple of remote spots away from highway traffic and enjoyed some time in the great Plains wind, as we enjoy every spring.

As the sun set, a newer round of storms was firing on the retreating dryline farther W–mainly SSW of CDS. We headed back into Vernon for some dinner at a greasy-spoon cafe, monitoring convective trends and plotting a course to observe the most intense cell after dark near LTS (an easy drive to the N) if it survived. By the time we got to LTS, the storm had been a marginal supercell but already was weakening, and another one mostly hidden to its NW was ramping up, moving mostly away from us, and starting to produce hail.

Regardless, we parked off a dark dirt road a couple miles SW of town and watched the slowly decaying original storm sail NNE to our SW, W and N, producing a few photogenic lightning flashes along the way. The second of them that I chose to keep (above in the header, and linked here), was the most fascinating. It appears to be a downward-directed attempt at a step leader that never contacted the ground, then got lit up as a secondary branch by a conduction connection (crawler style) somewhere deep in the cloud material above. The groundward-aimed scythe shape, as viewed laterally, makes me wonder how it would have appeared to a fortunate observer standing directly beneath–fortunate not to have been touched by the leader!

A few more flashes and the storm was done…and so were we. We headed home after a decidedly stress-free storm-observing trip having spent plenty of quality hours traveling together as a happily married couple.

Our PING trail for this day. [PING date is ending date in UTC.]

Pray for Rain

January 22, 2015 by · Comments Off on Pray for Rain
Filed under: Summary 

Southwest OK
23 Apr 14

SHORT: Pleasant storm trek to southwest Oklahoma, intercepted three photogenic storms with varying supercell characteristics.

After a rather long chase-free winter and early spring, Rich Thompson and I has a rare juxtaposition of mutual days off with the potential for supercell development along the dryline, and in one of our favorite storm-intercept areas: southwest Oklahoma beyond the Wichita Mountains. We headed out the familiar I-44/FSI/US-62 path well-trodden by generations of intrepid storm observers, hooking NW out of LTS to intercept an early, promising cell that peeled off the dryline and across the Texas border to our WNW.

Sure, we figured this day to have low tornado potential, given marginal low-level shear and the likelihood of high cloud bases. Nonetheless, there’s nothing like the excitement of anticipation in drawing closer to a developing storm on the first chase day of the year. It’s a sensation that cannot be experienced more than once per year–the promise not only of a storm awaiting through the low clouds and a decreasing number of miles down the road, and of what my lie beneath still unseen, but of an entire new storm season now kicking off in earnest.

Our storm obviously had a high base as seen headed west on OK-9 out of Mangum, and we stopped a couple miles E of Vinson to admire the view. The storm turned rightward and moved almost due E, Nof Mangum and toward the Granite area, but with its core of rain and severe hail right over OK-9 near Granite. This forced us to loop around through Mangum and NE past the badly drought-depleted Lake Altus, meeting what now was a very wet, messy, windy, outflow-dominant storm near Lone Wolf.

Even with a mesocyclone apparent in person and on radar, we didn’t desire continued engagement with this storm given: 1) its chaotic, heavy-precip structure, 2) its projected core path right over the best road ENE toward HBR, and 3) other storms developing in a better environment to the SW. We plunged back SSW toward LTS, going through a couple of heavy flanking-line cores to the Lone Wolf storm that reinforced our decision to bail.

Positioning near Martha, we turned W toward a newer, also high-based storm, encountering this impassioned plea in a church parking lot. Southwestern Oklahoma was (and still is) mired in a devastating long-term drought, the last of this intensity being during the Dust Bowl days of the 1930s. Supercells or other isolated thunderstorms really aren’t the solution to the drought for the farmers and ranchers there. While a supercell can drop a narrow swath of temporarily beneficial heavy rain, that only briefly helps those who happen to be in that swath–that is, as long as the storm doesn’t also offer damaging hail, severe winds, and/or a tornado. Within a week or less, the ground is dry again.

A nearby spot away from the busy highways offered us a casual and quiet place to watch this initially nondescript storm develop a strikingly beautiful cloud arrangement, including a nicely tiered and textured arcus accentuated by the light of the magic hour. Meanwhile, to our N, the storm unleashed some CG action over the Okie red-dirt countryside.

With the sunset hour at hand, we did a small jog to the E toward Friendship, catching the weakening storm base’s permeation by a few minutes of warm rays, before heading back down to a newly showery US-62 for the ride home. We thought that was it for the chase day, until one cell developed near the highway, became dominant, and cruised NE toward the Wichita Mountains.

Even though Rich had to be back by midnight for a shift, we had just enough time cushion to do a zigzag N out of Cache, past the Wichita Mountains Wildlife Refuge visitor center, and E a short distance to a vantage for watching the storm drift over the Wichitas. It turned out to be a severely tilted, marginal supercell, the main updraft region completely displaced in the vertical from any part of the anvil–even most of the backshear.

Serenaded by the wind and occasional crickets, we watched the beautifully striated storm emit a few brilliant lightning flashes that illuminated its stacked low-level structure–all beneath stars that speckled the cobalt sky of deepening twilight. All in all, this was not a bad way to start the aught-14 chase season–one that would turn out to offer very few tornadoes but an unprecedented variety of striking storm structure.

Our PING trail for this day. [PING date is ending date in UTC. Any pings after 00Z were pasted onto this map as well.]

Last Chance near Last Chance

March 11, 2014 by · Comments Off on Last Chance near Last Chance
Filed under: Summary 

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 SWto the Nto 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.]

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