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.


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.