June 24th had potential. Good deep layer shear, decent moisture, high instability and a mesolow along an outflow boundary would provide all the ingredients to produce several supercells in South Dakota. We spent part of the afternoon in Murdo and waited for something to happen. Finally by early evening, a tornado warned supercell formed and right turned strongly into far south central South Dakota and eventually into Nebraska. This storm had great structure and tried several times to produce a tornado. It did produce hail to baseball size.
June 16th was a surprise day. We were figuring on a down day or a day that had very marginal potential. By late morning, several storms developed along the east side of a surface low in northern South Dakota. Many were tornado warned. We couldn’t get there in time coming up from Salina, Kansas, but we did manage to catch the storm that was the largest and longest tornado warned in South Dakota. It had beautiful structure and very large hail. Also it produced a large, but weak tornado that ripped through the Menno area causing lots of tree damage and damage to several tin buildings.
From mid through late May, nature did not cooperate with an active severe weather pattern. A large ridge of high pressure, along with a persistent gulf coastal frontal boundary would prevent decent moisture from returning to the plains states. When you operate a tour, you still have to find the little nuggets nature gives you. The pictures below are those nuggets from May 19 through 31st.
July 15 and 16 took me to northern Nebraska and South Dakota to play storms along the dryline. Shear wasn’t expected to be very strong, but enough to help generate supercells, and to my surprise tornado warned supercells. July 15th took us to Nebraska where a large supercell developed west of O’Neill. This storm was fairly high based, but rotating nonetheless. It produced golfball sized hail and had very high winds once it lined out. July 16th took me to central South Dakota along the Missouri River where numerous severe storms formed near dark. Lightning was decent and the hail was large, also to golfball sized.
June 26th ended up being my favorite chase day in June. Good moisture, a boundary and strong shortwave energy would set the stage for supercells across North and South Dakota. I started the day in Rapid City and ended up near Mobridge as two tornadic storms formed not far from the North and South Dakota border west of the river. It was absolutely stunning scenery watching this storm interact with the surroundings! It produced at least two tornadoes, possibly more as it wrapped in rain. It also produced tons of hail to tennisball sized. The structure later in the evening was stunning!
It is a rare occasion that you get woken up at 6 AM with a TORNADO WARNED supercell out your window! June 21st was one of those days! A cluster of supercells developed overnight and moved southeast across south central South Dakota. We intercepted one near Kimball, SD that produced 4.25 diameter hail! Later that day, an old boundary would provide the lift and convergence to develop the best storm of the day, that also produced hail to 3.5″ in diameter!
June 12th was the worst of nightmares weatherwise. Great shear was all the was present this day, as too many overnight thunderstorms would not allow much instability to form. Storms formed along a boundary, with no cap, and became outflow dominated quickly. Too many storms would form from Nebraska, northward through North Dakota. Despite several tornado watch boxes, no decent tornadoes developed this day. The images here were taken within 50 miles of Murdo, SD.
June 6th had all the ingredients for significant severe storms, including tornadoes. Good shear, a strong wave, good instability and respectable moisture would set the stage for supercell storms. SPC issued a MODERATE RISK and associated tornado watch box for western South Dakota. By 1 PM we had arrived in Wall and stopped for lunch. A couple of small towers were going up south of us. After 45 minutes of our lunch break, a supercell rapidly developed south of town. As we gathered the clients and headed out, it didn’t take long for a tornado to form. This tornado, although not terribly strong, stayed on the ground for 25 minutes. We could never get any closer than 15 miles from it. Later, the storm turned into a monster HP supercell before lining out.
What an event!! After watching model run after model run I couldn’t resist the 1700 mile round trip to eastern South Dakota from Denver to chase this one!!! I arrived in Sioux Falls, SD around 3 PM. I couldn’t decide whether to sit tight, head to southern Minnesota or head west towards the advancing front. Each situation had its positives and negatives. After much analysis and some very quick driving, I decided to head west towards the front, which now was firing a string of supercells along it. I targeted the southern supercell coming across the Missouri river north of Pierre. I caught up with it east of Oneida and what a sight it was!!! It took about 10 minutes for it to drop its first of 7 tornadoes that I saw. The structure was second to none as this beautiful striated updraft produced one tornado after another. The largest and strongest tornado developed southwest of Wessington and tracked southeast near Wolsey to southwest of Huron before dissipating. It stayed on the ground over 40 minutes and resembled the Manchester, SD tornado from June 24, 2003 (which I saw from the south side). Finally, the storm produced one last tornado southeast of Huron as it weakened moving towards I-29.
I wasn’t expecting much this day, but couldn’t resist a play off the Black Hills of South Dakota. By mid afternoon a VERY high based supercell formed near Hot Springs. As it moved off the hills, it weakened and almost died. Then, not far from the western edge of the Pine Ridge Reservation, it intensified and became a wonderful high based hailer. The structure was as textbook of an LP as one could get. The most beautiful part was right at sunset as the sun lit the updraft and anvil, complete with reflected convection in the anvil.