July 18th would be my last chase day for the month. We started the day in Bismark, ND. By early afternoon a boundary would set up over northern South Dakota. A tornadic supercell formed along this boundary southwest of Reva and anchored itself there for about an hour. We quickly went west and south on the Enchanted Highway and caught up to it in time to watch a substantial tornado. This supercell was fairly HP, but gave us a nice show with a moderately visible cone tornado. As it roped out, a new core on the south side of the supercell, pushed the tornado east as it became pretty visible. Most of the duration of the 12-14 minute tornado, it was poorly contrasted. Fortunately it occurred in a area that has little to no population. This storm was also highly electrified with numerous very close and intense CGs occurring.
We started EARLY in the day on July 18th, with a tornado warned supercell riding along and slightly north of an outflow boundary from previous night’s convection. This storm had that slightly elevated look but still was tornado warned almost its entire 6-8 hour life cycle from around 10am till about 4-6pm. It did produce one tornado we could confirm. We eventually blew it off and headed for another supercell, a big beastly HP storm, south of Jamestown, ND. This storm produced an EF3 tornado north of Berlin, ND, and was a monster. As this storm lined out, another tornado warned supercell formed on the outflow from the Berlin storm and became briefly tornado warned.
One thing to note, the first two photos, the Juanita, ND tornado, are from a friend who was with us. The menacing photo of the Berlin storm and rain wrapped tornado was nuts! During that shot there were amazingly rapid rotating rain curtains that you can see rotating from left to right (south to north). The tornado was occasionally partially visible through the wrapping rain curtains.
July 16th was probably my favorite chase day of 2011! We ended up in Bismark, ND, located just northeast of a mesolow and along a weak boundary that extended towards Grand Forks, ND. We ate lunch and waited in a local mall where it was cool. Temp and dewpoint were INSANE this day with my weather station reading 91/82! Crazy obs! The SPC mesoanalysis page showed a Sig Tor value in the teens and supercell composites in the 30s. Great number and not surprising based on the environment. With decent 500 mb winds aloft and respectable low level shear, we knew if any storm could get going in the capped environment, it would likely be a supercell and have a definite tornado potential. By mid afternoon, towers developed along the boundary and late afternoon, our supercell, the storm of the day, would form. Made it really easy for us to intercept since we were basically 30 miles from the congestus that ended up growing into our tornadic monster.
By 4:15 pm, our storm had developed a good updraft and downdraft, and it immediately developed on skinny pencil funnel that extended halfway to the ground. At 4:30 pm, a major wall cloud had formed, and was developing strong rotation. At 4:33 pm the first of 4 tornadoes touched down. It lasted until 4:38pm when it dissipated. The storm quickly cycled and dropped another much more significant tornado at 4:41pm and lasted until 4:55pm. This tornado was much stronger and developed a significant debris cloud. Both of these tornadoes occurred just northeast of Regan, ND. After the second tornado dissipated, the storm started its cycling process again, and this lasted quite awhile. It never looked like it would produce another tornado while we maneuvered to get back in front if it (lots of flooded roads to work around!), and it pummeled us with hail to golf ball size.
Finally, south of Bowdon, ND, we were able to get back in front of it and dropped south about 8 miles to get a view of the updraft. It looked in a considerably weakened state, with a strung out updraft and smaller core, but it managed to drop a truncated elephant trunk shaped tornado about 10 miles to our west. It was briefly on the ground, 2 minutes and fell apart. The southern end of the storm became very well organized as a lowering formed directly west of us and started spinning as it approached our location. You could hear the waterfall sound as the RFD blasted around the now rotating wall cloud. A substantial cone shaped funnel formed at 6:25 pm and touched down a mile to our northwest at 6:29 pm. It stayed on the ground and morphed from a truncated cone, to “Wizard of Oz” type tornado, to a stove pipe and then an amazing double walled beast as it passed less than a mile to our north! What an incredible tornado! At 6:41 pm it dissipated and the storm rapidly weakened.
At that point, we decided since we needed to be in Grand Forks for the night, we would leave our dying storm and head towards Grand Forks, only to be greeted by a tornadic supercell east of Devil’s Lake! We stayed with this cell for an hour, until it lined out and weakened. We made it to our hotel by 11PM, with all guests (and my guide!) in great spirits! It isn’t often you see what we did this day, and to have it over mainly open terrain is even better. Beautiful storm, magnificent tornadoes and little damage.
Not much to say about this day. Not a lot happened, except for a near midnight CG barrage north of Miles City that made me smile. The one shot below (first photo) of the old homestead with the CG next to it, is definitely one of my favorite of the year.
July 14th was a day that had a lot of promise. I didn’t think there was a tremendous tornado threat with the relatively weak low level shear from surface through 850 MB, but overall shear, moisture and instability were quite supportive of nicely structured supercells. It did not disappoint! We had several nice supercell storms to watch. The first storm of the day was an LP, then classic supercell, then almost died as it ingested tons of dry air, and finally came back to life and became the storm of the day. A couple other supercells were also very pretty and quite severe. Most storms produced hail up to baseball size and were very electrified as well.
Although nothing spectacular happened July 13th, a late show developed with a pretty shelf cloud/undercut supercell, that was fun to photograph. This storm was severe, and produced hail to golf ball size northwest of Miles City, MT. Later, after dark numerous CGs occurred that were also fairly photogenic.
One other photo included in the writeup (first image!) occured the day before, July 12th, east of Lewistown, MT overlooking a valley below. One of the prettiest pure scenes for me to photograph in ages. A young 11 year old farm girl named Jordan came out on a Gator 4×4 and chatted with everyone. She enjoyed meeting us all and couldn’t believe storm chasers were up where she lived. Everyone loved it!
July 11th resulted in a lot more than I thought we would get. Modest CAPE and shear ended up producing a few pretty supercells, one of which anchored east of Chadron, NE. Storms had decent structure and respectable electrification. We sat around Chadron for a big part of the afternoon until things finally started developing. Several funnel lookalikes occurred that were called in as funnels/tornadoes, but of course were later discounted.
Early July kept me close to home for a needed break between tours. It had been a long and rewarding season, but was far from over yet! Caryn and I stayed within a few miles from home and were treated with 4 straight days of great lightning!