Tag Archives: atmospheric science

A Tornado Outbreak in Wyoming

Wyoming is not exactly “tornado alley”. According to the National Oceanic and Atmospheric Association, the entire state averages only 12 tornadoes per year. Kansas, by comparison, receives eight times as many tornadoes each year despite being 15% smaller in area. Although a tornado in Southeastern Wyoming played a pivotal role in the VORTEX 2 project, Wyoming generally tends to be too dry for severe thunderstorms.

June 13th’s chase came up somewhat suddenly for me, based on a notification I had received about this outlook after being out of town, and not focused on the weather, the prior weekend. For some reason, before I even looked at anything else, weather models, discussions, etc., I had a feeling something major was going to happen.


This day somehow felt different, right from the start.

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By 2 P.M., storm chasers were all over the roads, and at places like this Love’s Truck Stop in Cheyenne, Wyoming, watching the storms begin to form and trying to determine the best course of action.


The decision we all were faced with was which set of storms to follow. The storms forming to the North were in the area previously outlined by the Storm Prediction Center as having the highest risk for the day, and in an area with great low-level rotation. But the storms to the South looked more impressive on RADAR.

Often, we need to continue to re-realize that the best course of action is to follow our instincts, and to follow them without hesitation or self-doubt. That is what I did, opting for the storms to the North.

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It did’t feel like a typical day in Wyoming. Storm chasers everywhere. Highway signs were alerting motorists to the potential for tornadoes and large hail. Moisture could be smelled in the air. With a moderate breeze from the East South East, the atmosphere felt less like Wyoming and more like a typical chase day in “tornado alley”

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When I  caught up with the storms in Wheatland, Wyoming, hail larger than I had ever seen had already fallen. One of the good things about following a storm from behind is the ability to see hail after it has already fallen, as opposed to trying to avoid hail out of concern for safety and vehicular damage.

I stayed in Wheatland as long as possible, knowing the storm would head Northeast and I would have to leave Interstate 25. One of the disadvantages to chasing in Wyoming, as opposed to “tornado alley”, is the sparseness of the road network.

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So I sat there for roughly 20 minutes. Looking at the storm, it felt like something was going to happen. All the necessary conditions were there, and the appearance and movement of the storm felt reminiscent of other situations which had spawned tornadoes.

I took a chance, using roads I had never traveled before, hoping the roads I was following would remain paved so I could follow the storm North and East.

There was a half hour time period where I had become quite frightened. I could feel the adrenaline rush through my body as the clouds circled around in a threatening manner less than half a mile in front of me. I lacked the confidence that the road would remain paved, or that I would have a reliable “out plan” if a tornado were to form this close.


After lucking out with around 10 miles of pavement, I suddenly found myself driving over wet dirt, and, at 20-30 miles per hour, gradually falling behind.

Luckily, I once again found pavement, drove by some of the natural features that makes Wyoming a more interesting place to drive through than most of “tornado alley”, and once again encountered large hail that I felt the need to stop and pick up.

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Almost an hour later, and significantly farther north along highway 85, I finally caught up to the storm, just as it had dropped it’s first, and brief, tornado. And, this time, I was a comfortable distance from the thing! Unfortunately, this tornado would lift off the ground in only a few minutes.

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Not too long after, I received notification that other chasers, following the storms that had formed farther South, had seen a much more impressive tornado, closer up, and had gotten better photos (the above is not my photo).

It was a strange day. Not only because Wyoming is not the typical place to see tornadoes. It also felt strange, as I had managed to do something impressive, yet still had reason to feel like a failure.

Most storm chasing is not like it is portrayed in the movies, with people getting close to storms all the time and getting in trouble. Most days, chasers do not see one. Seeing a tornado one day out of five is a very good track record for storm chasers.

Going out on a chase and seeing a tornado of any kind is impressive. Yet, to be truly happy with my accomplishment, I had to accept the fact that there was something better out there- something I did miss out on. This is a struggle we all face, in common life situations such as jobs, relationships, events, houses, etc. We often know we have done well, but always have this idea of something that is even better out there. Knowing this can make us indecisive, which will often leave us with nothing. In the age of text messaging and social media, evidence of such options has become extremely abundant, and quite hard to escape.

In a connected world, in order to be happy with ourselves, we need to find a way to both believe in ourselves, but also be accepting of the fact that someone else, somewhere out there, has done better. For that will always be the case, and we now have instant access to that knowledge. We cannot let knowledge of someone else’s more impressive accomplishments dampen our enthusiasm for our own. Otherwise, we will likely never be content.

Lessons Learned?


Some events in life are clear.  They can be clearly labeled a success or a failure.  The reason for the success or failure is clear, and there is a clear lesson to be learned from it.  One comes out of an event of this nature much like an idealized application of the scientific method.  A piece of new information is obtained.  It either strengthens a pre-existing theory or calls it into question.

In the real world is not ideal like that.  Many observations, an many of our life experiences do not even produce a clear cut data point, a clear “success” or “failure”, or a clear lesson to be learned.  This was certainly the case on my first storm chase of the 2016 severe storm season, on Saturday, May 7th.

It was a day that did not require me to travel far to chase.  In fact, I returned home to Denver less than eight hours after departure, something that cannot typically be expected.  If I lived in a City right in the heart of “tornado alley”, such as Oklahoma City, Topeka, or Lincoln, I would expect to be able to regularly see great storms without having to allocate an entire day.  However, Denver is a bit West of the region most prone to severe thunderstorms, much the same way Chicago is a bit East of that region.  When I moved to Denver, I did have to make some adjustment with regards to storm chasing, but I did not significantly alter my expectations regarding time spent or distance traveled on a typical one-day storm chase.

Saturday’s severe storm setup provided me with a somewhat familiar dilemma, and one that is even more common chasing storms in Colorado, where many thunderstorms are initiated by orographic features.  Severe storms need a certain environment to thrive, one that is warm an moist, but also with some kind of boundary to create low-level wind sheer, which creates the rotation necessary for supercells, and tornadoes, to form.

Saturday was not that kind of day in the Denver metropolitan area. The Denver area spent the entire day in a thick field of low level cloudiness that prevented the air from warming up.  The high temperature at Denver International Airport was only 53.  Ideal conditions were farther East.  That day the high in Fort Morgan, close to where a lot of the violent storms would hit, was 68.  As is the case with any storm chase, it is important to get into an area where the environment will be favorable for storm development.  So we drove East of the cloud deck.


But then it happened, forced by the Palmer Divide, thunderstorms formed just to the North and East of Colorado Springs, in an area where conditions were not favorable for severe storms.  Sitting in Byers, roughly 40 miles East of Denver, we had a choice; do we go South and West to catch the storm now, or do we hang back and wait for the storm to reach our current location, in a more favorable environment?

Staying back means potentially missing what the storm does in its early phases.  However, being more aggressive means possibly missing a different storm, that may form in an area with better conditions for severe storms.  On Saturday, after some deliberation, we decided to go after the first storm.  We felt cold air, possibly the coldest I have ever been in while observing a thunderstorm, and saw a strong downdraft.  This is consistent with an atmosphere that is cooler and drier than the ideal one for producing severe weather.


The storm raced northward.  We ended up being a little bit limited by the relatively sparse road network in Northeastern Colorado, having to follow the storm along a series of dirt roads that connected Strasburg, CO (along I-70), to Wiggins, CO (which is along I-76).


In fact, there was even a time when we were pretty much directly under where the RADAR echoes showed the center of circulation to be.  This situation sort of made me nervous.  At the time I was thinking that if a tornado were to form, it might form quite close to my current location.


For roughly an hour, it seemed like the storm was kind of teasing us.  One minute, these clouds would appear to be lowering and rotating, as if a tornado were ready to form, the next minute it would all just simply disappear.


It was around this time that the storm reached I-76 near Wiggings.  Here, the storm interacted with a previously existing boundary, and, according to sources, went tornadic.  However, we were never able to observe the tornado.

After this, the storm transitioned, as many severe storm clusters often do, into a large bow echo.

This is a clear indicator that the storm is entering a different phase, often associated with decay.  It has become dominated by downdrafts.  The most likely result is severe straight line winds.  At this point in time, the best thing to do is simply observe this gigantic thunderstorm, as despite no longer having the low-level rotation necessary for tornado formation, it is quite breathtaking in its own way.

Storm chasing, and storm observation is about more than just tornadoes, and it is quite unfair to describe all chases that do not result in viewing a tornado as a “failure”.  We really could not have picked a better place.  There was only one other cluster of storms that day that produced numerous severe storm reports.  That one formed farther East, a bit later, and produced tornadoes when it interacted with the same East-West oriented boundary.  We also still observed some interesting severe convective storms.

But still, it is frustrating to know that there was indeed a tornado, verified, within ten miles of where I was sitting, and I somehow did not get to actually see it.

I know being in position to view this storm was quite challenging, and it is likely that few chasers found themselves in such position to view the tornado.  But I wonder, had my group reached the I-76 corridor 15-20 minutes earlier, would we have been in the right position to see it?  We knew this boundary was there, and it was in the area with the most ideal conditions.  Was going after the storm initially an exercise in impatience?


The day ended with a return trip, along I-76, back to Denver, through the area that was clearly just recently pelted with hail.  I returned knowing that there are aspects of this chase that can be considered a “success”, but others that can be considered a “failure”.  I also returned still wondering how to strike that proper balance between aggressively chasing after storms that initiate, and patiently waiting for storms to form or reach the location where the conditions appear to be most favorable.