Front row for an atmospheric masterpiece (Part 1) » Yale Climate Connections


I soon realized that chasing storms is way harder than I could have ever imagined, especially solo. The sheer amount of driving time and analytical second guessing can cause anyone to doubt the whole grueling effort. It is an experience filled with many rather low “low lows” and some extremely high “high highs”. And after seeing the first of what could be even more tornadoes to come, for me anyway, it was worth it. 100% worth it.

Waking up that day in early May on the border between western Oklahoma and the begging of Texas, the morning weather surprised me. Huge calm filled with thick fog, making the other side of the small lake dark. Not super prone to tornadoes, and could I see them anyway? This feeling stayed with me for much of the day, just like the fog. I later realized the folly of that thought, remembering that the atmosphere is changing every moment. And that the biggest changes often happen during daylight hours, when an incredible amount of solar radiative energy added to the atmosphere literally stirs things up…and burns away the fog.

That early fog didn’t deter the National Weather Service’s storm prediction center. Scientists there had issued the second-highest level of warning on a 5-point scale (MODERATE) anticipating all potential severe hazards (flooding, large hail and potentially strong tornadoes) for a wide area of ​​north-central Texas and southwestern Oklahoma.

In large low-pressure systems like the one I was approaching that day, the boundaries of different air densities, temperatures, and moisture contents serve as starting points for severe storms. The interaction of these ever-changing variables within these boundaries mixes influencing their own particles and those of neighboring particles as a function of thermodynamics and fluid flow. The particular storm system that day had a highlighted area of ​​risk called the “dry line”: a generally north-south trending boundary of hot/dry and hot/wet conditions.

(Source: National Weather Service Storm Prediction Center)

I headed to my first target area just inside the Texas border and drove through a drought ravaged landscape. While bulletins on church signs asked people to “pray for rain,” this seemingly fertile valley of brilliant green, streaked through the red Texas dirt, offered at least that morning a moment of appeasement. He ended up being the only real one of the day. As I admired the silent landscape from a lookout before descending into the valley, I noticed two dead calves to my right, harbingers of the harshness of even the most beautiful vistas.

As I was parked at a gas station in Shamrock, TX eating a slice of fried pepperoni pizza (a natural wonder in its own right) and looking at computer models and chart/satellite scans , the first storm cells of the day began to fire nearby to my west, moving northeast. It was still quite early in the day, but the spacing and depiction of these storms aligned somewhat with one of the best “day of” patterns, the HRRR. I was hooked and my excitement for any storm exceeded any ability to wait and see how the larger situation further south would unfold. As thunderstorms approached, I pulled into the driveway of an abandoned farmhouse and got out of my van, quickly realizing I needed a sweater. That thought set off alarm bells in my head: cold air is the opposite of what a severe storm needs to sustain itself. Even though nothing had formed further south yet, I gave up on those storms and started begging down.

About an hour later, I rolled down my window and held out my hand: the air was now warmer, more humid. I got out of the van to get a better sense of the atmosphere around me and found an isolated supercell pushing about 50 miles to the southwest, basically moving towards me. From my experience with a cell in Arkansas a few weeks earlier, I knew to avoid getting stuck north of a severe cell: it was important to go south of the storm. I spotted it just as it was performing its first obvious atmospheric magic by dividing into two different cells, just like in biology. In the atmosphere, this division most often occurs when one cell breaks away and generally moves north, with the remaining cell generally moving east.

I saw this split happen with a storm chaser named Brandon, from Nebraska, who said he had been hunting for 13 years but worked at a pharmaceutical company. Seeing someone else hunt and chat excitedly as we analyzed and watched the storm was my first real shared moment with another hunter. This brought to light how unique this area is and how amazing it is that many are drawn from all over to experience these phenomena. Like butterflies to a flame. “Street smart” for observing many storms first-hand, he had gained extensive first-hand knowledge.

Sunlight shines through the gap between the splitting supercell, with the eventual storm tornado on the left, and its northward partner on the right.

As the storm began to look more ominous and the cloud-to-ground lightning intensified (a sign of a strengthening storm), Brandon and I parted ways, taking different approaches to stay ahead.

I headed east to a north-south highway from where I could easily observe the approaching supercell. When I pulled onto the lonely freeway, I was flabbergasted to see dozens and dozens of vehicles lining it, turning a normally desolate farm road into a teeming amphitheater of weather nerds watching a free show. This notion of hunter convergence doesn’t always happen, but when it does, creates a chaotic scene that is both beautiful in its culminating premise of collective observation of nature and its power, yet terrifying in its ability to create a sometimes incredibly dangerous driving situation.

A tornado warning for the storm had just been issued, the chirping warning ringing out in rounds from people’s cellphones. A lowering of large clouds had established at the base of the storm, known as a wall cloud, a usual but not always necessary part of a tornado’s descent after a storm. This ominous and intimidating progression was accompanied by hail the size of ping-pong tables which began to fall from the sky. I was inspired by an elderly hunter couple who had opened the back door of their vehicle, sheltered but still able to watch the storm outside, with no risk of headbutts or concussions.

Most of the vehicles started heading south to get ahead of the storm as it started to approach the highway where we were all staying. Didn’t want to rush too much and miss watching the storm from outside, better to drive all the time and watch out the window. But it was a needle to thread to stay between the rotating cloud wall to the south and the rain/hail core to the north. I succeeded, and as the storm passed to my south, I started looking for routes east to follow it. The map only showed a real road and when I got there, I followed several other vehicles down the dirt road, knowing instantly that what I had dreamed of seeing for years was finally unfolding in front of me.

Look for Part 2 of this story on June 16.

Editor’s Note: Photos and captions in this series by Charlie Randall, except where noted.

Charlie Randall, photojournalist, former meteorology student, and now storm-chasing enthusiast living in Toronto, travels across the United States to observe extreme weather conditions and their aftermath.

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