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.

LONG:
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.]

Atmospheric Underproductivity

May 20, 2011 by · Comments Off on Atmospheric Underproductivity
Filed under: Summary 

NW OK and SW to Central KS

SHORT: Assorted convective towers over NW OK and central KS, mushy storms in SW KS, twilight macroburst in northern OK.

LONG:

One year to the day after a chase that was most memorable for all the right and wrong reasons, Ryan Jewell and I left Norman for the PTT area at about noon. We hoped to follow a dryline supercell across a narrow warm sector and then be there for its mature interaction with a pronounced warm front, and the mesocyclonic bliss such processes often entail. Alas, the atmosphere had other plans.

On the way up, early initiation (before 18Z!) yielded a mess of multicellular and occasionally supercellular storms in SW OK, the anvils of which we could see. We chose not to be distracted by those “sucker storms”, and instead forge NWward with steadfast resolve for our target area, where both low-level hodographs and deep-layer shear would be stronger.

Along the way, near Seiling, several deep towers erupted in the free warm sector, seemingly along nothing more robust than faint differential-heating patches. These would glaciate for 10-30 minutes, then dissipate, leaving behind residual anvil shadows and a few souvenir raindrops. The appearance of such midday convection, well-removed from either the dryline and the warm front, dichotomously encouraged us (no problem getting storms today!) and troubled us (too many storms today?).

As we headed N through P28, convection began erupting in a band up and down the dryline from NW-SSW, boosting hope for a targetable storm, since we still were well out of reach for the activity up near I-70. One storm crossing the KS-OK border quickly acquired flying-eagle structure in reflectivity and standout VIL, while darkening the skies to our SW. Although the low-level SRH wasn’t too favorable in the immediate area, thanks to some earlier veering of surface winds ahead of the dryline, the flow was starting to back a little again. We were excited that this could be our target storm, moving NNE then NE into a progressively better environment with time. Too bad several other storms formed in its immediate vicinity, messing up the structure before it got to us.

The most spectacular event of the whole trip then happened in a flash. As we waited just off the NE edge of PTT, a CG from one of the leading cells struck a sheet-metal building across the road from us, instant FLASH-BANG, its white-hot column dispersing into a vertical necklace of brilliantly glowing, golden-orange plasma beads that blew northward in the wind for a second or two before dissipating. What a pyrotechnic display!

Our target storm became entangled in the mess of surrounding convection and lost its structure before reaching PTT; so we targeted a tail-end cell and headed W several miles out of PTT. By the time we met the “anchor” storm, it was but a small, smooth updraft base with a short tail cloud. By the time we found a stopping place for me to take a photo, the updraft cloud column shriveled to a pathetically flimsy chimney, soon to vanish altogether.

Surely this couldn’t be our fate for a day of such promise?

We scrambled NE toward Lyons to intercept a small but intense storm that materialized from the southern portion of the same precip area N of PTT, but it too turned to mush by the time we got there. All that was left: a strand of towers that had no chance to mature before crossing the warm front. Game over.

Here we were just S of Lyons, on the warm front, breathing in some of the most deliciously refreshing, richly moist air a human or storm could ingest, all for naught.

On the return drive from HUT-ICT-OUN, we smacked into an intense gust front just S of the OK/KS border, then stayed in near-severe winds for at least 25 miles across a swath of Kay and Noble Counties. This was an impressive macroburst, one of the most sustained I’ve encountered, blasting northwestward from a SSW-NNE band of high-based showers. Overhead and to the S we could see a patchwork of virga and loose mammatus in the twilight, and also encountered intermittent light rain reaching the ground. The headwinds buffeted us hard, shaking the vehicle some and compelling a little white-knuckle gripping of the steering wheel on Ryan’s part. Dust and grit reduced visibility to less than a mile, making noise like sleet as it bounced off the windshield at times.

We also saw a sporadically splendid display of anvil crawlers and a few CGs from the northern cloud shield of the MCS that was moving across the OKC and Blanchard areas at the time. After retrieving my vehicle at Ryan’s, I went to eastern Norman and attempted some lightning shots ahead of the leading gust front, but nothing too spectacular…I kept missing the brighter and closer CGs before the electrical area got too close to shoot safely.

Stormy Sunset Salvation

June 30, 2009 by · 2 Comments
Filed under: Summary, Uncategorized 

9 Jun 9
Northwest Osage County OK

SHORT: Killed Kay County supercell as it moved into Osage County. Intercepted complex multicell/supercell cluster from two sides near Webb City, with brilliantly sunlit convection astern.

LONG:
A couple days of prognostications indicated the best play on this day would be the frontal zone from the central high plains to the Ozarks, preferably W of I-35 where the road network and terrain each are friendlier. Analyzing the situation from our prior night’s lodging in SLN, it became screamingly apparent the too-well organized morning MCS was spewing lots of cold outflow and shunting the effective frontal zone well southward across south KS. The western part was being shoved into drier warm sector air with more westerly sfc component, while at least the middle segment seemed to be interacting with a sfc moisture plume characterized by mid 60s to near 70s F dew points. A mesolow also was forming W of ICT, potentially concentrating convergence in its vicinity from the area S of HUT through the ICT region.

Armed with that concept, we (Elke and I in one vehicle, Two Fogels/Two Dogs team in the other) headed for our target area of south-central Kansas, with a great lunch at the IHOP in HUT along the way. Scattered Cu dotted the SE-SW horizon in a band obviously corresponding to the outflow boundary. As we waited for initiation near Cheney Lake Dam, the boundary continued to sag S, and the winds actually backed from ENE to N. Oh no…the mesolow not only was riding the slowly progressive boundary, but moving E thereon! Meanwhile the warm sector winds to our S still remained out of the SW, with a more southerly component hanging in there E of PNC to BVO. Time to move SE and stay ahead of the mesolow…

As we cruised E from Conway Springs, storms erupted to our E along the boundary, and to our S over north OK. The former would have a shot if it could stay on the boundary (big “if”), while the latter erupted in the hotter, deeper mixed boundary layer, but more discrete with less undercutting potential from the outflow boundary. By the time we reached WNF, we decided to go after the Okie storm, now right-moving over Kay County all by its little lonesome.

Dodging a few small, transient left splits, we maneuvered with steely determination E and S toward Webb City OK, in the beautiful, green-carpeted, southwestern Flint (Osage) Hills. The storm maneuvered E toward our location, into better storm-relative sfc winds, larger hodographs, and lower LCLs, with a stone cold death wish…for itself. Just as we got in good position to its ESE: shrivelus convectus minimus!

A messy complex of storms behind it, to our WNW-SW, became better organized, even sporting decent gate-to-gate mesos for short periods along a curving, embedded cyclonic shear zone. With sparse roads and a good W view (albeit with a hazy boundary layer), we let the initially distant assemblage of bases and cores — including one striated but small updraft cylinder — move our way. Very briefly — less than a minute, a finger of cloud condensate connected ground and ambient cloud base to the very distant WSW, but it was just too far away to ascertain whether this brief feature was rotating — a scudnado or the real deal. By the time I ran across the road for a better photo angle, it was gone.

After that, the storm cluster and its precursory anvil CGs drew closer, forcing our southward retreat to US-60. What appeared to be an anchor supercell on its SW flank grew feeble quickly (again, upon entering more backed surface winds and greater moisture…go figure), allowing us to “core punch” its moderately rainy and baseless carcass driving W on US-60.

By now, the sun was getting lower, and we decided to bunk down in PNC instead of driving up to 2.5 hours out of the way (to home), given the more western location of the next day’s forecast area.

The best part of the chase day, as often happens, came behind the storms, near sunset. The newly soaked, rolling green hills and valleys smelled a fresh and invigorating earthy aroma. Mild, moist air came to life with the calls of bobwhite quail and many wild songbirds, while a couple dozen nighthawks arose from the fields and flew off toward the setting sun.

Out across the big eastern sky, a beautiful double-rainbow festooned the back of the retreating storms to our E, followed by marvelous layers of light and shadow across the sides and tops of big new towers forming another anchor storm. Across a few fleeting minutes, the sunlight tones warmed considerably, reflections off the big towers in turn lighting those beneath and casting ever deeper hues across the scene. Finally the show ended, but not before a brief blaze of bronze from the final rays of the day.

It was a neat way to salvage an otherwise disappointing chase day and an egregious atmospheric underperformance compared to the 15% sig-tor outlook that had been issued for central KS early in the day. 😉