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Our convoy of three minivans and eighteen chasers departed Blacksburg on time (0900) Monday morning May 18th to head out to the Great Plains. Little did we know the magnitude of the logistical challenges we – especially trip leader Dave Carroll – would face during this venture. The initial hint came during the first fuel stop in Tennessee. Two of the three VT Fleet Services gasoline credit cards wouldn’t work, so Dave pulled out his phone and eventually found out the cards had never been activated prior to their being handed to us. Thus a 15 minute gas stop turned into an hour and a half interlude. Another – chronic – problem was keeping the chase computers supplied with mobile internet access. Dave had purchased data cards with which to add balances to the accounts but each time the resupply required a lengthy phone call to the mobile data company…something not in the national advertisements.

Knowing that our day 2 target was likely to be the Texas panhandle we pushed to Conway AR the first night. Tuesday morning thus entailed a bleary-eyed departure for points west on I-40. However when the 1630Z SPC Day One convective outlook came out we changed plans on the fly. The target now was somewhere along the corridor between Lawton OK and Wichita Falls TX. We rolled through the Oklahoma City metro area and dove southwest on I-44 as storms fired early due to little or no capping. (This situation would continue during much of this trip.)

Just south of Chickasha OK we pulled off the interstate to seek shelter as a large hail-bearing cell loomed in front of us. On radar the biggest hail size looked to be windshield destroying stuff so we plunged underneath a bank overhang – after asking permission – with enough vertical clearance to allow us and our rooftop mesonets to fit underneath (an important point to keep in mind regarding events later that night). That intermission lasted a half hour or so before we poked our collective noses out from underneath shelter. Splashing through the flooded streets we made our way back out to the interstate and continued southwestward.

Unfortunately our delays, the lack of a cap, and the high precipitation (HP) nature of the plentiful storms all combined to frustrate our chasing attempts this day. We pulled off I-44 south of Lawton to watch radar and noticed a tornado-warned storm to our southwest. Stopping in a church parking lot east of the interstate we were in hopes the cell would cross left-to-right in front of us. However, even though we could see curved cloud bands overhead flowing into the storm the HP characteristics obscured our view of the inflow notch.

Tornadic storm inflow

As the rain approached we retreated eastward and southward, bound to pavement by the very wet conditions in southern Oklahoma. The overall road network in this region is fair but many of the soggy routes we would have taken were dirt or gravel and were thus impassible for our minivans. Thus we began a series of eastward and southward dashes, first in an attempt to see the business end of several storms and then eventually to escape the growing squall line / MCS. Several hours of this bobbing and weaving added to the general exhaustion of the group and we eventually booked rooms at a hotel in Ardmore to settle down for the night.

However Nature wasn’t through with us this day. After everyone found their rooms Dave and I kept watch on radar as we felt it was likely that we’d have to move the vans under cover somewhere to avoid hail from oncoming cells. The good news was we didn’t do that. The bad news was that a storm moving directly toward Ardmore became tornado-warned. We therefore gathered up all the chasers – including a few that had trudged through the rain to a nearby restaurant – and drove 20+ miles south of town to watch this storm blow through from a safe distance.

The snail-paced storm finally cleared Ardmore after a couple of hours and we drove three vans full of very tired people back to town amid heavy rainfall and a nocturnal lightning show. Dave peeled off to stop by the restaurant and let the students pick up their paid for (but not yet eaten) meals. Meanwhile the graduate student driving the third van went to the hotel with me to discharge our passengers. The grad student had eaten something for lunch that disagreed with him so he was not only tired but not feeling well. Even so he wanted to be helpful so he intended to drop off his crew underneath the hotel overhang to avoid the rain. Unfortunately that overhang wasn’t anywhere near tall enough to allow the mesonet to clear and the latter was almost totally removed from the top of the van. Fortunately neither the van nor the hotel suffered any discernible damage but the mesonet roof racks were toast.

The next morning Dave was afforded the chance to exhibit his considerable “MacGyver” skills as he concocted a method to strap the mesonet on top of the third van using materials from a neighborhood sporting goods store. This arrangement actually worked pretty well and lasted the remainder of the trip, but devising and installing it required Dave to arise very early on the third day of the trip to get us back on the road. That too, added to the challenges of the trip.

Wednesday the chase thus started a bit late but it wasn’t a big deal as conditions weren’t looking great. We motored our way south into Texas, diving south of I-20 to the village of Comanche southwest of Ft. Worth. Our plan was to intercept a triple point created by an outflow boundary and the dry line in hopes that the combination would fire up convection. To keep it simple…we busted. Calling off the chase early we traveled northwest to Abilene TX where we spent the night.

Thursday May 21st proved to be the nadir of the trip. The previous day the transmission in my van had made a couple of suspicious “clunks” while slowing to a stop. Since nothing else happened untoward my eyebrows slowly lowered and I gave it little additional thought. Thursday our plan was not to chase but to reposition for storms in southeastern Colorado on Friday. So we leisurely drove from Abilene up through the Texas panhandle to Amarillo. In that city we had to go through a series of traffic lights that put us in stop and go mode for several miles and the van’s transmission really didn’t like it. A strange “zipping” noise began to occur every time it changed gears. But once we got back out on the open road it settled down…for a short while.

However the problem quickly grew bad enough that my copilot both checked the Web and texted his brother back home. With that info in hand we determined that this was indeed a serious problem. My copilot then checked and found that the next town, Dumas, contained a Chrysler dealership. So I had the unhappy task of radioing ahead to Dave that my van needed to be looked at. Now late in the afternoon the dealership said they could take a look at it in the morning (Friday morning of Memorial Day weekend).

So we made an unplanned overnight stop in Dumas and Dave took the van in to the dealership first thing Friday morning. Long story short: the transmission was shot and needed major repairs. Of course nothing could be done over the holiday weekend so Dave pulled another rabbit out of his hat of tricks and I drove him back to Amarillo where he rented a six passenger SUV for the duration.

Leaving the broken van behind (and my stack of trusty DeLorme paper maps!) we continued the chase Friday, driving up to southeastern Colorado in hopes of finding some convective mayhem. Shear values were good but the instability was too weak. This is the best we could do:

Hokies watching a fading storm

However sunsets on the High Plains are always noteworthy and we caught a good one. This photo doesn’t do it justice at all:

High Plains sunset

Photo by Robert Stonefield

After overnighting once more in Dumas (the hotel was pretty good!) we set our sights for Saturday May 23rd on Colorado once again. We stopped briefly near Springfield but things looked good further west toward the Rockies so we jumped on a westward leading route to intercept. As we drove we could see some awesome towers going up and we turned north near the hamlet of Kim. This route paralleled the storm motion and I began to feel really good about our intercept chances. The road led through some incredible scenery which included mesas and small canyons but the excitement in the vans ratcheted skyward when a large wall cloud formed underneath the cell we were targeting.

Finally reaching La Junta we quickly filled gas tanks and utilized restrooms before retreating a couple miles east of town to a vantage point. As we watched the storm went tornado-warned and sirens began sounding in the area.

La Junta storm

Shortly thereafter the storm developed a large RFD cut which we kept a close eye on:

RFD cut

About this time someone reported a tornado on this storm in the general direction of the above photo. I have serious doubts that one actually occurred. The one photograph I’ve seen purporting to show the tornado was actually of the wall cloud we were watching at this time. Since then I’ve seen a video of dust kicked up by the rear flank downdraft that someone has used to claim there was a tornado. I’m really not a “tornado snob” but this one just didn’t happen.

We leapfrogged east of this storm for quite a while. At one point the inflow was so strong it was sucking up ground level dust and yanking it into the updraft. We kept ahead of the cell until it merged with others to form a squall line. At that point we pulled up stakes and continued east into Kansas before diving south of the line to overnight in Guymon OK.

Sunday May 24th dawned cloudy and cool, typical of the first half of this trip. I think it was this morning the next logistical snafu arose. Dave discovered that his credit card suddenly wasn’t working. The finance company had sent a new card (one with the new embedded chip) to his home and immediately activated it while canceling the old one he had in his wallet. Rectifying this entailed another hour or so on the phone while he convinced the representative on the other end that he really wasn’t in a position to retrieve the chip card.

Once that was cleared up we drove back to Springfield CO to briefly cool our heels at a local municipal park we’d discovered during a prior chase trip. Time outside the vans in the sun and on the grass did wonders for the group’s morale as we awaited convection to take hold. Once it did we pushed a couple miles west of town on a lonely road to check out a cell coming out of the southwest. I was able to snap this photo that represents (to me) the wide open spaces out that way:

a long lonely Colorado road to a storm

Although this cell looked good a number of other storms were popping up (no cap) and merging into a line so we decided to play the southern end. Moreover a number of other chasers were up north near Lamar and we wanted to avoid chaser convergence as much as possible. Thus we motored back south to Boise City OK to watch and wait until the “Tail End Charlie” cell took shape. When it began looking healthy we stayed with it, witnessing a wall cloud underneath the storm’s base.

Wall cloud on Tail End Charlie

As the cell continued its northeasterly drift we jumped in the vans and headed back north to Springfield where we turned onto an easterly route. We leapfrogged for a while ahead of the building convection and stopped literally on the Colorado / Kansas border to observe.

Storm approaching the KS_CO border

Continuing east and south into Kansas we oohed and aahed at the structure as more storms built ahead of the line. At one point we were faced with plowing underneath a developing cell or stopping to let it cross our path and risk getting clobbered by very large hail from the storm behind us. We chose the former option and had to punch through hail that was “only” half-inch in diameter. This storm was summarily ingested by the main cell behind us, creating some eye-watering structure that I missed since I was driving away from the merger.

During one of our final stops the low sun angle afforded some marvelous coloring of both land- and cloudscapes. One of my favorite photos involved this sunlit roll cloud in the foreground and a menacing mesocyclone signature in the background:

Money shot at sunset

As darkness fell we pulled away from the action and rolled back south to spend a second night in Guymon. As we did so one of the storms to the east dropped a nocturnal tornado that some folks excitedly reported as a large wedge. The National Weather Service official survey conducted the next day rated it as an EF-1 so, again, I had my doubts as to the veracity of the preliminary tornado reports.

Monday May 25th – Memorial Day – wasn’t really a disappointment in that we weren’t expecting much from the setup to start with. Departing Guymon OK we maneuvered northeastward toward Great Bend in central Kansas. CAPE values were off the charts but shear was in short supply. Stir in very little capping plus cold air aloft and hail storms eventually erupted all over the map.

After determining that Great Bend wasn’t far enough east we pushed further to the town of Lyons where we enjoyed a mid-afternoon lunch/dinner stop while waiting for the convective picture to become clear.

Dinner stop in Lyons

A nice looking discrete cell did go up east of Lyons but we were wary of chasing it. A number of other storms had popped up to the south and we didn’t want to get caught in a squeeze play amid multiple hail cores. Thus we sat still for a while until an outflow boundary fired some activity almost overhead. We then retreated a couple miles west of town to watch and wait.

After the “Tail End Charlie” cell on the developing line crossed the road east of Lyons we piled back in the vans and headed after it. Unfortunately the rural road network in this part of Kansas is composed chiefly of unpaved roads and the monumentally wet conditions once again dictated that we remain on paved surfaces. In addition by this time the storms had begun to coagulate into an MCS and chasing that mess was untenable. So we called it a day and headed to Pratt KS (yay!!) to overnight.

As we waited in the parking lot for Dave to pick up the room keys from the motel office we were treated to an overhead view of mammatus:

Mammatus over Pratt KS

We were all hoping the evening sun would dip below the clouds to provide underlighting for these features but such was not to be.

The next morning – Tuesday May 26th – dawned bright and clear and I managed to squeeze in a leisurely stroll before our morning forecast meeting. Given the setup we reluctantly set our sights on southwestern Oklahoma hoping that area would be slightly less water-logged than points east of there. Diving into the Sooner state we continued south to Frederick to set up. Parking on a ridge top east of town we watched a couple of cells go up to our west.

Two initial storms

The left hand cell became severe-warned and actually produced a horizontal tube vortex which reinforced our assessment of the tornadic potential in this area.

horizontal tube_2

It was touch and go for a while as to which storm we would chase. When the rain shaft under the left-hand cell shrunk substantially we actually headed back west toward Frederick to go after the right-hand cell. But as we approached town the former storm quickly pulsed back upward and we reversed course to get out of the now-growing rain and hail shaft.

Motoring east amid the rain this storm was at our 7 o’clock. It pumped out a substantial wall cloud and then a nice funnel while we were speeding away from it. That meant only the folks in the back of the vans got a good look – and pictures – of it before the funnel dissipated. When eventually we came to a crossing route far enough ahead of the cell we dove in front to get south of its track. As we crossed its path we witnessed the very clear separation between the tilted rotating updraft and the precipitation shaft, a characteristic of a supercell storm.

Punching back west a bit we pulled off the highway to observe this storm in hopes it would cycle back up. Unfortunately a very large cell south of the Red River chose this time to spew a strong outflow boundary in our direction which undercut “our” storm, weakening it. The silver lining in this was the passage of an active gust front that kicked up quite a bit of dust, accompanied by a massive shelf cloud.

undulatus behind the outflow boundary

We followed this activity for a short while until it became obvious that the sheer number of storms was rendering chasing impossible. (We had anticipated this in our morning meeting.) Thus we pulled off these storms and rolled northward toward I-40 to obtain lodging and grab some dinner to assuage a number of growling stomachs.

However Nature had other plans. As often happens a low level jet formed as the sun dipped toward the western horizon, intensifying some nearby convection as we motored northward. When the sun dropped low enough the lighting angle created some eye watering views that we couldn’t resist. Thus we pulled off the highway and jumped out with cameras in hand. This was the best photo I took at the time:

sunset supercell_2

As this storm continued strengthening we swapped directions and headed south to an eastern route to get closer, empty stomachs temporarily forgotten. We pulled off this road amid quiet pastures with wind turbines eerily groaning nearby. As dusk fell this was the back edge of the cell:

dusk storm and wind turbines

A cell to our north later produced both a brief tornado (which we didn’t see) and quite a lightning show (which we did see):

northern cell at dusk

As darkness settled over us the mosquito swarm grew to epic proportions (remember all the rain that had fallen over Oklahoma?) so we escaped back into the vans to head north once again. Our collective frustration at having mostly missed the funnel under the earlier storm had vanished…but the hunger hadn’t!

Our last day of chasing was to be Wednesday May 27th. The tentative status of the stranded van in Dumas TX was that the transmission parts would be provided to the dealership this day and the earliest we could pick it up was sometime Thursday. That would mean a long two day drive back to Blacksburg for a Saturday arrival. Thus during our morning meeting in Elk City OK we knew we needed to swing for the fences. It was – almost literally – the bottom of the ninth inning with two outs.

Our initial target was Arnett OK with the thought that storms would fire west of there over the Texas panhandle, making that a good location to start from. We drove northwest and arrived around noon, searching for a park in which to cool our heels. We actually found one and set up shop for lunch and relaxation while awaiting convective mayhem to begin. (While there Dave talked with the dealership in Dumas and found that the van with the mangled transmission didn’t just need a part replaced. It needed a completely new transmission and wouldn’t be ready for several more days. Thus after Wednesday’s chase was finished we would head straight to Blacksburg for a Friday arrival. The second Hokie Stormchase trip would pick up the stricken van on their way out.)

After a relaxing time of eating, basking in the sun, and watching radar I ventured a couple of blocks to a convenience storm that had a bathroom (none available in the park). When I rounded the corner I immediately noticed puffy white updrafts bubbling to the west, an indication that our location was right on target. We waited a bit for the convective situation to unfold before jumping back into the vans. When one cell became dominant we rolled out of the park toward the action.

Just outside Arnett we had a choice of a southwesterly or a western route. Partly (probably mainly) on my recommendation we turned west to intercept the storm as it cruised northeastward. When we found a spot to stop and observe the storm a few miles down the road I had a chance to study the structure. I was first puzzled and then a bit alarmed at what I was seeing:

First view of storm base

The white arrows point to two separate rain-free bases, and what I quickly realized was this storm – due west of our position – was in the process of splitting. If the southern updraft intensified it would likely turn right, probably accelerating and changing to an east-southeast trajectory while leaving us in its tracks. Once we all agreed on this potential we climbed back into the vans and retraced our steps back to the southwestern route we should have taken originally.

Unfortunately by the time we got ourselves straightened out the storm had indeed turned right and the precipitation (hail included) began encroaching on the road several miles ahead of us. However we could see a large wall cloud now under the rain-free base and when a funnel began taking shape underneath it we hurriedly pulled off the road to watch and snap photos.

first funnel

After this funnel dissipated without touching down we debated our road choices. The only real choice we had to get to the southern side of the storm without core punching was to retreat 40 miles east, catch a south route for 20 more miles, and then push back west. None of us were happy with this but we swallowed hard and did it anyway, hoping this storm would hold together long enough for us to get into position to watch it cycle.

As it happened instead of accelerating the storm actually slowed down dramatically near Canadian TX but maintained its intensity. Thus our hour plus journey to get south of it wasn’t a real problem. We found an open vista on a bluff overlooking the Canadian River valley and piled back out of the vans to watch and wait…and we weren’t disappointed. The storm was roughly 14 miles northeast of us here:

Overall storm structure with wallcloud over Canadian TX

As we watched a funnel dropped out of the wall cloud and touched down as a cone tornado:


It stayed on the ground and grew into a stovepipe:

Still down

And we got to see the ropeout stage:


Overall this tornado was on the ground for 14 minutes and was rated an EF2 by the NWS Amarillo survey team. Unfortunately it injured three people and damaged some oil rigging.

However this storm wasn’t finished. And because it wasn’t we didn’t give up on it quite yet. We pushed further west until we were directly south of the town of Canadian, wandering around a while to find another decent vantage point. (Most pulloffs were already full of other chasers.) We finally stopped at a less-than-optimum spot and witnessed another funnel ten miles to our north:

final funnel

Overall this storm pumped out four verified tornadoes, and the time on this photograph roughly corresponds with the final tornado (rated an EF0). Thus this funnel could very well have had circulation on the ground that we couldn’t see.

As darkness settled in we pulled the plug on the chase and began our long journey back to Blacksburg. That day may have been the bottom of the ninth with two outs but the bases were loaded and we’d just hit a grand slam. Not a bad way to end the chase!!