Austin McDowell Tornado Camp 2018

Tornado Camp Essay

by Austin McDowell

Another year, another tornado camp... this time successfully bringing back the University vehicle. I’d say it was a successful year based on that alone! Kidding of course, I was able to build upon what I learned from last year’s RiVorS (Rivers of Vorticity in Supercells) field project to this year’s NRI (National Robotics Institute) project. I was able to collaborate not only with Texas Tech students and faculty, but with University of Nebraska and University of Colorado folks as well. Being able to learn from so many people with differing backgrounds and expertise was truly invaluable. We were able to complete many datasets that I hope will be able to increase understanding and forecasting ability of supercell thunderstorms. In total we saw three tornadoes which all happened in the same thunderstorm in Colorado. These tornadoes were not your textbook tornadoes which form from the meso of a supercell thunderstorm, these were all lan. We were fortunate enough to see simultaneous landspouts, one cyclonic (counter clockwise) and one anticyclonic (clockwise) at a safe viewing distance on our first official day of chasing. On the last day of chasing we were able to observe a rather robust supercell in the southwest Kansas Northwest Oklahoma area that was nearly stationary for 45 minutes. The mesocyclone was strong, apparent by the large wall cloud, but rotation was not in the cards. Although we did not see a tornado in this storm it was valuable for research purposes comparing tornadic supercells to non tornadic ones. Although we travelled long distances for many ‘duds’ the trip was a considered a large success from the storms we saw on the first and last days.

I think tornado camp is a vital part of my experience in AOSS/CLaSP. The curriculum only has a handful of meteorology classes, the majority which focus on processes that are not directly thunderstorm related. Learning about severe weather that impacts folks across the country every day is vital to a meteorology education. I was able to apply what I learned from Dr. Marsik’s classes to severe weather forecasting in real world scenarios, ones that aren’t cut and dried like we see in a textbook. I used concepts from Dr. Keppel-Aleks boundary layer meteorology class to understand how eddies alter the moisture profile of the atmosphere as the day progresses. We saw scenarios in which one target area had better shear but lower moisture and the other had ample moisture but not enough shear. We, as a group of meteorologists had to discuss with each other why we should target one imperfect scenario over the other. This real world experience has amplified my experience with CLaSP.

I think all four of us, who started with different meteorology backgrounds, took large steps forward in our understanding of the complexities that com with severe thunderstorm set ups. I think the largest takeaways I had were that it is vital to consider the depth of the moist layer and how it will be modified throughout the day as well as observing outflow boundaries as setup points. The depth of the moist layer is important for a couple of reasons, the main one being mixing. As thermals grow larger and larger throughout the day there is air mixed down from higher and higher altitudes. If the surface observations tell us there are 70 F dew point temperatures at a location, we could get excited and think it is a viable target without considering the full picture of the boundary layer. There could easily be a layer above the surface with much lower dew point temperatures that can mix down and decrease surface dew point temperatures throughout the day. If this process occurs, we can expect the favorable

surface observation early in the day to become less favorable come time for updraft initiation. As for outflow boundaries we had many occasions where shear was not at the threshold we were hoping for. A target for 0-6km shear is 40 kts or higher for supercell thunderstorms. Due to anemic flow aloft we were only reaching 35 kts if we were lucky. Given this lack of shear we had to target outflow boundaries which gave us both a lift mechanism as well as a boost of shear necessary to reach supercell mode. We looked for outflow boundaries that introduced a backed surface wind. In particular. This backed surface wind both allowed for ample shear as well as made for a good-looking hodograph for storm relative helicity, a measure of potential updraft rotation. The tricky part about outflow boundaries is finding them on satellite imagery and observations. This skill I think I developed the most. It is critical to locate these boundaries to target the area with highest potential for robust supercells.

Overall, I learned even more than the first tornado camp I would say. I didn’t have much time to prepare for the trip, as I was added to the crew a few days before leaving but Dr. Weiss and crew down at Texas Tech got me back up to speed with severe weather quite quickly! Being able to build upon what I learned the first trip was fantastic, I was able to be more curious and ask deeper questions given my previous knowledge. I would strongly recommend going for a second time to anyone if internships fall through or if research allows! Thank you to all the faculty and staff at both Texas Tech and Michigan for making this possible, I hope this event can continue well into the future! Go Blue and Guns Up!