Storm Chasing Day 3: The Dust Front

We knew that the majestic, rotating supercell we saw yesterday (Tuesday 5/29/2018) would be very hard to surpass, but Wednesday ended up far exceeding our expectations. Even as early as the night before, the Storm Prediction Center only had “marginal risk” for severe weather over the Western Oklahoma/NW Texas region. But in the morning, the SPC had bumped this “marginal” risk all the way up to “enhanced” risk, completely skipping the “slight” category. Unlike Tuesday, the storms were expected to take the form of a strong, long-lived, and very fast-moving squall line instead of being discrete supercells. While these squall line setups generally do not create strong tornadoes, they can create extremely strong, straight line winds and large hail. And although we narrowly avoided some softball-sized hail, we were hit by several microbursts affiliated with a particularly powerful thunderstorm on the southern edge of this squall line, with the most powerful of these likely having winds in excess of 60 mph.

We started the day in Altus, Oklahoma and promptly headed nearly 250 miles northwest to Guymon, Oklahoma in the Oklahoma Panhandle, as this was where the most favorable conditions for storm development were. We had some entertaining discussions along the way, talking about everything from lucid dreaming and out-of-body experiences to simulated reality and artificial intelligence. We spent a lot of time debating whether objects as we experience them are objective realities or if the only realities in this universe are the atomic and subatomic particles that it is made of, with our experience simply being the “hologram” our body constructs from these physical objects. Yeah… there’s a lot to talk about when you are driving on the Plains in search of storms.

Along the way, we passed through Perryton, Texas – the town in which we stayed from Monday night-Tuesday, and from there, we took a turn back SW on Highway 15 to fill up on some grub at the Hungry Cowboy in Spearman, Texas. The food was alright, but they charged me 50 cents for a cup of extremely tappy tap water, so I won’t be going back. The drive along Highway 15 was noticeably flat, and that’s saying something for the Great Plains.

We also saw a super retro gas station in Spearman that I shot a photo of. It looked like it hadn’t been used in years, at least by non-commercial vehicles. Those big cylindrical buildings in the background store various types of grain (primarily wheat); we’ve seen dozens of them so far this trip. It’s tough to believe that you could fill a building that large with wheat, but then again, the Great Plains aren’t known as the “Wheat Belt” of America for nothing.

We left Spearman around 2:30 pm and continued heading west along the Oklahoma/Texas border towards the Rita Blanca National Grasslands. Storms initiated in Colorado around this time, and we could see their anvils to the WNW several hundred miles away. Oh, and did I mention how flat it was?

After taking a brief look at the radar, we noticed that these storms had ballooned in size and strength, so we ended up hooking north and going back through the Oklahoma Panhandle instead of hanging out in the Rita Blanca National Grasslands and waiting for storms to develop there. But storms soon began to fire to the southwest, and when we reached a T at road EE 0350 and I385, we decided to turn south and follow these storms.

While we were pulled over at the T and deciding what to do, a farmer whose farm was a couple miles north pulled up alongside us and asked us if we needed any help, and we said we didn’t but thanked him and struck up a conversation. He told us that the “famous dust bowl image” was taken a few miles “that way” (pointing west) and that farmers had learned lessons from the dust bowl. I found this image in Clayton, which was approximately 35 miles to the west in New Mexico, so I wonder if this is the one he was referencing.

Unfortunately, this storm quickly weakened and was hardly even producing any lightning when we got to it. The storms to the north, on the other hand, strengthened considerably, and because they were moving east extremely quickly, the route we took coming from the north was now cut off. We ended up having to go south on a narrow, muddy, and sandy road, but Chris is a fantastic driver and handled the road like a pro. Once we popped out near Perico, Texas, he took some gnarly pictures of his mud-covered Mazda 3. I have to say, the combination of the mud on the car, the mammatus in the sky, and the wheels turned at just the right angle make for a pretty sweet shot.

Mammatus clouds are the clouds that look like semicircular pouches in the top left of the photo and are formed when dense, cool air sinks from the cloud base in pockets. Mammatus clouds are frequently observed underneath the anvils of strong thunderstorms, and we can even get very weak ones in the Pacific Northwest on occasion. I ran across I85 (don’t worry, there was nary a car in sight!) to some railroad tracks on the other side (no trains in sight either) and snapped another picture of these mammatus.

After we reached Perico, we needed to get further east so that we could keep ahead of this rapidly-advancing line of storms. We headed east towards Stratford, and from there, we headed slightly north and took some awesome pictures of an incoming gust front/microburst. Gust fronts mark the boundary between the warm, moist air from within the boundary layer (the layer of the atmosphere close to the surface that is heavily affected by daytime heating and the effects of terrain) and the denser, evaporatively-cooled downdraft from the storm. Microbursts are simply a particularly strong downdraft that spreads radially when it hits the ground and causes strong straight-line winds in the process. The gust front is the “leading edge” of the storm’s downdraft and an advancing gust front is a great example of a “gravity current”, which is where a mass of high-density fluid flowing along a horizontal bottom displaces a fluid of lower density.

I think a more apt name for this particular gust front was the “dust front,” as the microburst in the downdraft kicked up quite a bit of dirt as it propagated over some recently-tilled farmland.

This dust was quickly approaching us and we braced ourselves for impact, but it ended up splitting to our left and right. I dashed out along a dirt road to try and experience the brunt of this microburst, and though I was a little late, Chris got a picture of me wistfully gazing towards the storm’s downdraft, complete with a weak mesocyclone to my left.

After stopping here for this view of the gust front, the line of storms had advanced to the point that we could no longer simply cut north but had to go east first. We headed back south to Stratford and began heading NE on Highway 54. But we got sidetracked by the three beautiful, back-lit, very weak local centers of rotation associated with this storm and stopped to take some more pictures.

After we finished, the line of storms we had initially planned to cut in front of had progressed so far east that we had no choice but to backtrack SW towards Dalhart and head east on Highway 15. But thankfully for us, this ended up being one of the best decisions we’d make throughout the entire trip, as we saw an absolutely spectacular double rainbow straddling the road on the trek east along Highway 15. We stopped to take some pictures, and it persisted long enough for us to drive through the darn thing. It was a truly incredible experience for us.

We eventually reached Spearman, Texas once more, and we decided to pull off and take some pictures of the storm’s shelf cloud at sunset. Shelf clouds are ominous, wedge-shaped clouds that form on the leading edge of a thunderstorm (aka: just ahead the storm’s gust front). They form because cold air from the gust front undercuts and lifts the warm, moist air ahead of it upwards, cooling this air to the point of saturation and creating a cloud in the process.

Fortunately/unfortunately (depending on how much of a thrill-seeker you are), we stayed a little too long in Spearman, and by the time we left, the storm’s intense hail core was just a couple miles away and was quickly approaching.

While we were able to avoid the hail by continuing our trek eastward on Highway 15, we bore the full brunt of several intense microbursts in the lee of the storm’s gust front. These microbursts sent tumbleweeds flying across the road, temporarily dropped visibility to less than 200 feet, and pushed our car sideways on the highway. I’d estimate these gusts were at least 60 mph and probably more. Once the mayhem finally calmed down near Perryton, Texas, I looked back and snapped a picture with my cellphone. Despite the graininess, this was my favorite photo of the day, as it clearly shows how defined the gust front associated with this storm was.

After we had gone through Perryton, things were getting pretty dark, but Chris got some fantastic photographs of the storm’s shelf cloud illuminated by lightning. Both of these were taken east of Perryton along Highway 15.

Instead of continuing to outrun this storm (which had, by this time, developed into a larger squall line and was moving east between 30 and 40 mph), we took advantage of a small break in the rain to our south and took shelter under a gas station in Shattuck, Oklahoma to ride out the storm with some other chasers. We were blasted by a heavy dose of wind, rain, and pea-sized hail as the squall came through, but this was nothing compared to the 4-inch hail that was reported in Higgins approximately 10 miles to the SW. The cashier at the gas station told us that his mom lived in a trailer in Higgins and that the trailer was likely destroyed, but that he wasn’t too concerned because she was renting the trailer from a school nearby and that they were not liable for the damage.

After this storm had passed, we headed northeast to Woodward, OK and called it a night. If Tuesday featured incredible, rotating updrafts, Wednesday featured intense, ominous downdrafts and the brightest rainbow we’d ever seen in our lives. Both days have been exhausting, and we’re all looking forward to a day of calm tomorrow.

Charlie, Chris, and Joey