Around 2 p.m., the field coordinators sent the word that we would be repositioning toward Watonga, OK. The FC vehicle hadn’t filled up on gasoline, so we searched around Clinton for a place to fill up on diesel fuel. After what seemed like a very long time, we were on our way to the target. I think the armada was halfway to Watonga by the time we got out of Clinton. As it turned out, it really didn’t matter, since the next target was a bit further to the west, so we all met in the middle (at Canton, Oklahoma).
Just west of Canton, Jeff Snyder, Jana Houser, and others shot the breeze while waiting for storms to develop. At first, development was very slow, and had all the earmarks of a squall line in the making. For this reason, I wasn’t too optimistic. In fact, I had every hope of making it to Norman in the evening. Alas! The atmosphere had different plans. With each failed attempt at convective initiation (thunderstorm development), the new attempt would exceed the previous attempts ever so slightly. I suppose it kind of reminded of a battle scene: the men on the front line would sacrifice their lives and bodies to make headway for the troops behind. These “sacrificial” attempts at initiation would go up in a seemingly identical way: at first, they would “cauliflower” as a group of towers, then they would get “choked” by the capping layer, then they would become horizontal with a laminar appearance. Methinks that these successive attempts would each cool the capping layer by just a little bit, until any remaining convective inhibition was removed.
After the cap broke, several different updrafts formed. The storm evolution was very slow – in spite of the extreme instability – probably, because the deep-layer shear was just too weak. At any rate, we drifted east to Okeene, and then dropped just south of town to observe the storm. After about a half hour and a few “repositionings” south and east, the storm began to show some slight signs of rotation at cloud base. After not too long, the storm became a full-fledged supercell. Unfortunately, new cells grew to the southwest of the updraft along the front, which then precipitated into the supercell’s updraft and weakened it. However, a new circulation began to develop to our southwest as convective development occurred further down the cold front.
This new mesocyclone was quite intense at the mid-levels, and one of our FCs (Erik Rasmussen) was quite certain that it would “tornado.” The frustrating part of the deal was that I couldn’t see what was going on behind me during this period (we were driving south at the time). Finally, we stopped just north of 40 on the 281 spur NE of Bridgeport, OK. The structure was really fantastic, and for a while there, I thought it might actually produce. The RFD began to move around the circulation, but it was quite rain-filled. I think this may have reduced the buoyancy somewhat. At any rate, darkness was settling on us, so the FCs called it day. The same storm complex we saw produced a tornado in Anadarko, Oklahoma. An earlier storm in NC Oklahoma produced a tornado near Tonkawa. It was somewhat disappointing – but then again, that has been the theme of 2009.
The field coordinator vehicle just south of Okeene.
New convection developed to the southwest.
Ominous -- but benign -- wall cloud near Bridgeport, Oklahoma.
The structure was amazing.
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