Entry 4 - Storming up to the Canadian border

jallen's picture

22 May 2012: We departed Clayton New Mexico on the evening of May 21, with the idea of storm chasing through the northern part of South Dakota. We knew it was going to be painful to make the journey and would require hauling through the night to make it in time.

To put it into perspective when you are in the states only for a fixed part of the season you become a little more willing to do the hard yards as you don't want to miss anything. By the time the sun rose we were mostly through Nebraska.

We had breakfast at Winner, South Dakota, hoping that a little bit of that would rub off on us and continued to push north...and further north with things eventually setting up for a 5% tornado risk in northern North Dakota.

The first cell quickly formed literally on the Canadian border near the corner with Montana and began to track east. It looked nice but was just too far away. A second cell formed west of Minot, ND developing the telltale highly sheared supercell structure on radar and we quickly closed to approach it north of Minot.


Superb colours and powerful updrafts of the Minot, North Dakota supercell as it intensifies. Picture: John Allen

On first glance we were a little surprised in the elevation of the base, but it's a long way for the moisture to come from the Gulf of Mexico up to the Canadian border. Still, the cell was nicely structured, and had some severe hail (1.25 inch, 3 cm) along with reasonable rotation.


The dynamic motion was impressive but the supercell was just beginning to warm up. Picture: John Allen

It tried a few times to produce more substantial wall clouds, but it wasn't until it approached the Canadian border that it really dropped down and formed a strong tail-cloud and wall cloud right in front of us, after most chasers had bailed south.

Shortly afterwards in the distance in fading light we saw what we believed to be a tornado just over the border with Canada. Unfortunately the distance from us when it finally decided to happen made really difficult to really get what we were looking for, but the structure was definitely worth the effort.


The supercell is approaching the Canadian border as it is lit up by the setting sun. Picture: John Allen

One of the more odd aspects of the day was when a Customs and Border Protection agent pulled up to ask what we were up to (about 10 miles from the border) right after we observed the possible tornado. He mentioned that if we were looking for something to photograph that he saw a Moose on the road about a mile from us, before we explained we were chasing storms, much to his amusement.

On another day the same system might have produced tornado after tornado...even on the particular day you are never really quite sure what you will get dished up with.

Its interesting that two years ago on this date (May 22), a cell in a slightly more moist environment in northern South Dakota produced a violent tornado near Bowdle.

Stepping back to last year, a cell produced the Joplin EF-5 tornado which killed 162 people. Its funny how particular dates seem to produce these powerful storms more often than not. It does make you wonder whether its just our nature to see patterns or whether there is really something to it.

I guess missing the Bowdle storm when chasing here two years ago made me more hesitant about not make the long drive as I really didn't want to miss out again. When it comes to thunderstorm environments, the differences can be quite minute but the results can be poles apart, which makes it interesting to look at the similarities with historical events and the climatology.

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