Admittedly, the setup for this chase looked pretty marginal to me from a few days out. If it had been May or June instead of March and my first chase of the year, I probably would've sat this out. As it happened, I'm glad I didn't. However, it still stands that this was not a slam dunk event.
I chased with Ben Holcomb and his friend Cory Watkins. We left Norman at around 11:30 AM with an initial target/staging area of Shamrock, TX. There was only a narrow window of opportunity according to the model forecasts - only in a narrow, meridionally-oriented band would sufficient 500 mb flow overlay the 850 mb speed max. Although this was right at the dryline, forecasts suggested moisture would progressively mix out east of the dryline resulting in surface dewpoints in the 50s at the dryline. It didn't quite go down that way, as about 60° dewpoints survived up to the dryline througout the afternoon. As a result, analyzed CAPE was much higher than forecast.
We took a food break at the DQ in Shamrock waiting for the skies to clear for the onset of heating and for a more specific target to come into focus. Eventually we saw clearing preferential to our south and decided to mosey down U.S. 83 after sitting on a hill just southwest of Shamrock briefly. On our way south we observed initiation of a cell southwest of Childress.
This cell became dominant as we approached it from the north. We met it in Childress. The storm wasn't particularly strong or organized in Childress. It seemed to be having trouble throwing off a few left splits. However, it was isolated with little indication of other convection developing nearby. Therefore, we decided to stay on it, moving with it on dirt roads in far northwest TX.
We were chasing in Ben's Ford F150, so crappy/rough roads were not a problem. It seemed we were mostly alone while on FM268. The storm continued to seem to struggle in the environment it was in: it remained high based and was spitting out downbursts, but nothing would sustain itself. Even as we turned north towards the Red River on Hollis Rd., the storm continued to look like nothing more than an ordinary thunderstorm.
The bridge across the Red River into Oklahoma was fun - crosswise wooden planks with wooden trusses and two rows of 2-by-8s for tire treads to cross the 75 yards of mostly sandy pit that was the dried up river. A sign said, "Weight Limit: 3 tons", and there were three vehicles on it at the same time! Fun. We made it across fine, though. Back to the chase...
The storm finally started to organize once it crossed into Oklahoma. From a vantage point a few miles southwest of Hollis, we observed the storm, which had developed a healthy flat, rain-free base, develop a shallow wall cloud that began to rotate. In a few minutes, it went from no wall cloud to a rapidly rotating one!
The storm did not produce a tornado on that cycle, but even after seeming to lose organization, it quickly reorganized. We had only moved east a mile or two before we thought it was going to produce, this time just two or three miles south-southwest of Hollis.
Again, it did not produce, but it seemed closer than before. Again the storm appeared to temporarily become disorganized before reorganizing, now as we were passing just west of Hollis on our way north. A few miles north-northwest of Hollis, the storm became organized enough to spit out a few funnels not too far from us. This occurred as a storm to the southwest of our storm had begun merging with our storm causing aberrant behavior of our storm. Road options forced us to watch the complex behavior under our storm from probably no more than one mile to the east of where the funnel clouds were forming. Strangely enough, the funnels were forming under what appeared to be an anticyclonic wall cloud, as the cyclonic member was several miles farther west-northwest still, with a strong precip-laden push of possibly RFD air separating the two. This could have also been a stream of air from the other storm impinging on our storm. Anyway, although none of these funnels touched down, the rotation and motion was pretty intense for a few minutes at this point.
We moved north and east just a little bit more, where the storm gave one last hard attempt at producing before going on a break.
As noted above, the storm visually became the most disorganized since it first developed a wall cloud southwest of Hollis. At this point I was beginning to think we were out of luck for a tornado this day. We began driving east on E1550 Rd. to reposition in a better road network. As we drove east and pulled away from the low level structure, amazing storm-scale structure came into view. I told Ben to stop so we could get shots of the stacked plates structure that had formed on the storm!
As we continued east and got far enough away from the storm for it to fit into our camera lens view, even more stunning structure emerged. This alone was satisfying enough for me. Seeing this, I didn't mind so much not seeing a tornado.
I'm fortunate to say I've seen structure like this before. In fact, the structure on this storm bore an uncanny resemblance to that from the western Nebraska supercell (the one that produced the La Grange, WY tornado) on 5 June 2009.
After sitting in this spot taking structure shot after structure shot, we noted that the storm appeared to be reorganizing. So we progressed east and north to Mangum. We lost sight of what was going on under the base as we passed through Mangum. However, once we got north of town, an ominous sight appeared under the storm. We had no idea what was going on given the precip shrouding, but suddenly the prospects for tornado production from this storm seemed much better.
And just as luck would have it, some miles north and west of Mangum, we saw the storm spit out a tornado that appeared from behind the left side of the heavy rain shaft. It was brief, but its motion suggested there was something else in there. Other chasers claim to have seen a wedge in there at around this point. It seems plausible, but we never saw it.
Somewhere in this sequence of events, we were nearly struck by lightning as a close bolt (perhaps a positive stroke) struck close enough to cause a snapping sound of electricity arcing amongst the power lines on the other side of the road we were on just a second or so before a deafening crack of thunder with no rumble. I've heard this crack before...it sounds like a cannon or rifle being shot. The lack of a rumble seems to me an indicator that the bolt was close enough so that the sound waves propagating from the channel all passed us at the same time and/or canceled each other out through destructive interference. We were fairly exposed where we were, so we ran for our lives back to Ben's truck. Ben giggled as he held his camera in my face to get my reaction as I fled for safety. We had a good laugh to lighten the mood when we got back in the truck.
Likely in response to increasing shear from the intensifying low-level jet as evening set in, the storm kicked it up a notch, going fully tornadic. It would go on to produce at least two other tornadoes that we saw. The second of these last two was quite photogenic as it twisted, writhed, and roped out a few miles to our west. It was dead silent as this second tornado roped out.
We decided to call the chase shortly after this. The storm was starting to die anyway as the loss of daylight also brought the loss of instability despite the synoptic conditions (the setup was only minimally acceptable for supercells and tornadoes, not incredibly supportive). Interestingly, as we were making our way back towards I-40 via state highway 6 east of Carter, Ben drove us under some kind of very small-scale (i.e., hardly larger than the highway) and nearly-tornadic strength circulation that popped up out of nowhere. We weren't really near where the mesocyclone would be (if there even was a distinguishable one anymore), so we're not sure exactly what it was. It was strong enough to rock the truck slightly as it passed over. Our ears didn't pop, though, so the pressure drop must not have been very strong.
Despite my reservations towards this setup, this ended up being a great way to start the season!
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