In the Dust Bomb
Protection KS
18 May 13
SHORT: Intercepted outflow-dominant mess of storms in SW KS with gustnado and dusty air currents.
LONG:
Favorably strengthening mid-upper level winds were expected to boost deep shear atop an increasingly well-defined dryline that, by mid-late afternoon, would set up on the east edge of the central and southern High Plains, near 100W. We had diagnosed an 850-mb dry slot left by an earlier wave aloft that was likely to lead to a shallower and more easily mixed moist layer over potential NW TX and western OK dryline targets, leaving is with western KS. The closest available part of western KS to us was southwestern KS. Hence, that was our rough target on this “day before the day”. Very rich moisture and backed surface flow were expected to reach parts of west-central and southwest KS before dark, but could it get there in time to be tapped by storms that likely would fire off the dryline beforehand?
Out the door early enough, Rich and I headed up the Northwest Passage, fueling and meeting the esteemed storm-observing firm of Fogel, Fogel, Weitzberg and Brown (and two heavily panting leonbergers) in WWD. There, we all were greeted by the full-body, hair-dryer feel of 96 degree F air blowing past. When the car thermometer (which is fairly well-calibrated in Norman to the nearby mesonet site) hit 101 deg F just across the KS line, between Sitka and Protection, we knew that was just too warm to preclude serious outflow from eventually taking over any storm that developed in that environment. However, we also expected richer moisture (supporting 70s F surface dewpoints farther E along the border) to advect into the area after peak heating, thereby lowering LCL and boosting CAPE. Which process would prevail first?
We all headed E back into the mid-90s heat, and a shady rest area near Coldwater where the big dogs could get out and walk some without suffering heatstroke. There we also met Ryan Jewell, watching towers bubble up and occasionally glaciate along the dryline from NNW-W-SW. The gathered crew (four of whom are pictured here) represented a large collective of storm-observing experience, which makes some of our decision-making this day even more peculiar! Since they may not wish to be positively, pictorially identified with this chase day, we may only know their monikers (l-r) simply as Big Dog Daddy, Downtown, The Roach, and Jumpin’ J-Hawk, with Gran Rogelio behind the camera.
Patiently this motley bunch awaited the arrival of the better moist layer that we could see in the form of haze and lower-based cumuli off to the E and SE. One of these, the high-based little Cb pictured here, moved NNE and eventually evolved into the Rozel cell. Had we known what it would do, we would have followed this seemingly pathetic little plume with mouth-foaming fervor. Alas, on this day, we simply did not. With this cell moving closer to the moist axis, I still can’t fully explain why we chose to go SW toward the bigger, messier activity coming out of the Panhandle and still in the drier air, except for some hopes it would not get outflow-dominant before reaching the richer moist layer we could see to the ESE.
Meanwhile, a storm farther N (and legitimately out of reach) was already tornado warned and apparently producing rain-wrapped circulations as it approached I-70. Longstanding convection in the northeast TX Panhandle and extreme northwestern OK was growing in size and depth, glowing with blood-red reflectivities on radar and a deepening visual darkness in the southwestern sky.
Someone mentioned the possibility of anvil shadowing cooling the temps, lowering LCL, weakening mixing, and perhaps allowing the moist layer to advect into the inflow region relatively unadulterated. It wasn’t bad reasoning, per se, but the large size and SW-NE, quasi-linear orientation of the cluster to our SW should have been a clue that it wouldn’t wait for the rich moisture before spreading its load of outflow all over the surrounding countryside.
As we approached via southwesterly zigzag, the cluster seemed broad and disorganized with some updraft area on the south and east sides. When we stopped, S of Protection, the updraft area obviously was getting undercut by outflow, and the high-based, multicellular mess started its predictable forward-propagational heave. Cold outflow blasted past us to the E and SE, and a weak gustnado buzzed eastward across a field to our NE.
Dust rose from roads and fields, jacked skyward and forward in dense plumes, scenes from the Grapes of Wrath swirling through our minds as ribbons of fine soil blasted past. J-Hawk photographed and sepia-toned two of us pathetically immersed in the lofted dirt.
Massive dust-bombing wasn’t why we drove over 200 miles, though it did offer its own interesting photographic adventures. Nonetheless, this was the hand we pulled from the deck. Richer moisture did move into the inflow layer of this storm complex, but by then it evolved into a raging, N-S squall line that ate up every other convective attempt in its path (including the tornadic Rozel supercell that had gotten entrained into its N edge). One last view of the convection at sunset, from near Camp Houston OK, and it was time to plod home, regrets over choosing the “wrong” storm tempered by hopes for the next couple of days of potentially significant tornadic potential closer to home.