Marshmallatus

Every year since 2010, I have co-led, with Dr. Josh Durkee, a storm-chasing field course for meteorology majors at Western Kentucky University. There are many learning objectives for this course, and few of them are related directly to tornadoes and the typical events associated with storm chasing. Therefore, we strive to give students numerous opportunities to test and reinforce their education while also rewarding them with memorable experiences that excite them about transitioning into their careers.

On May 15, 2022, our group awoke in Woodward, OK, after chasing a supercell for five hours across southwest Kansas and northwest Oklahoma the day before. At our morning discussion, the students targeted a diffuse boundary drifting southward near I-35 as the instructors reminded them that we preferred to stay on the westward extent of the day’s risk for severe storms. As usual, we wanted to avoid the denser forests and complex road networks so that students could actually observe the atmospheric processes in action.

As storms began to take shape around 5:00 p.m., we were drawn briefly as far east as Wetumka, OK, as we watched a mesocyclone cycle through a couple of iterations of ominous-looking wall clouds. Soon after, we realized that road and visibility options were unacceptable, so we retreated west to our hotel in Ada (~60 miles southeast of Oklahoma City).

After checking in, we headed south with hopes of finding some large hail left over from a recent cell that passed nearby. We also knew that there would be the chance for possible photo opportunities featuring the sunset, rainbows, lightning, or mammatus from the ongoing storms southeast of us. We quickly saw some anticrepuscular rays, a first for many students, as we searched for large hail along rural roadways and fields. After finding quarter- to golf ball-sized hailstones near Fittstown (~10 miles south of Ada), we pivoted to finding some elevated terrain or clear fields to maximize visibility of the horizon.

Almost immediately as we traveled west, we caught glimpses through the trees of impressive mammatus developing to our north. Approximately 3.5 miles west of Fittstown, we found a hill with a bit of a clearing. Trees still obscured much of our view, but we could almost see the western horizon as the sun was about to touch it. The mammatus were now well-developed overhead and visible in almost all directions. We spent nearly an hour in that location as the setting sun and the growing mammatus clouds combined to create a dynamic skyscape. Meanwhile, the ambient sounds added to the memorable moment as we heard nearly continuous coyote yips and howls, calls from Chuck-will’s-widows (often confused with whip-poor-wills), mooing cattle, humming pumpjacks, and distant thunder. 

The evening ended with students sharing their photos with each other and with the world via social media while the instructors reflected on the enduring value of these experiences for the students and for themselves. “Marshmallatus” is a keepsake of our wonderful visit to Pontotoc County, Oklahoma.