South Dakota Tornado Outbreak and Intercept

Chase Day: June 24, 2003

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I never really thought that I would see a storm like I saw on Tuesday evening. Ever.  

On Tuesday, June 24, I watched the same storm produce tornado after tornado after tornado for more than an hour, with two or more tornadoes on the ground at the same time, THREE different times!  It was simply unbelievable. The Weather Channel is currently showing someone else's video of the storm that we saw --- it is Wednesday morning at 1 a.m. now in Sioux Falls ---- and the video shows three tornadoes on the ground concurrently, with even a fourth funnel beneath the large wall cloud. This activity occurred near Centerville, SD, in Clay County and Turner County, south-southwest of Sioux Falls.

Here is how the day went---and how darn lucky we were.

On Monday the four guests and Chuck Doswell arrived in Denver for the final tour of the season, Tour 6. Later that afternoon looked like a BIG supercell and tornado day near North Platte, and we were able to get there by 6 p.m. But, a strong cap prevented storms until dusk. We had some fun with severe storms south of Ansley after dark, and stayed in Kearney for the night.

The outlook for Tuesday appeared fantastic for tornadoes, if the cap would break. The cap was very strong again over Nebraska, and I was nervous that it might prevent storms again in and around my initial target area of Custer County, in the middle of the state. By late morning we were heading north from Kearney, and the thinking by then was that we probably would have to head farther, towards U.S. 20 in Northern Nebraska, where convergence was better. Very humid east winds were over SE SD, with more southerly winds in north-central Nebraska. Dew points were near 70F in NE, and mid 70s in SE SD!  

The sky during the early and mid-afternoon looked good, as flat cumulus and stratocumulus were widespread. This told us that, at least, there was no strong subsidence, and that the cap seemed more breakable than yesterday. After lunch in Ansley, the attendant at the gas station allowed me to sit down at the boss's computer in the filling station to check the latest data. We needed to go further north until we started to hit SE or E winds --- at least as far as U.S. 20 from Bassett to O'Neill. At Taylor I elected to take 183 to Bassett instead of 91 and 11 to Atkinson. This decision came back to haunt me. I like to error to the east when there are strong SW winds aloft, as on this day, but Bassett seemed to be a little closer to the best convergence at the time. When we arrived in Bassett around 4 p.m., radar began to show a blip of a cell southwest of Mitchell, SD, well to the northeast. Well, this was quite a ways outside of our original target area, but it was also obvious that the cell was in a fabulous spot, meteorologically, for tornado production. The observation at Mitchell was 86 over 77, with an east wind at 10 knots! It would take about two hours to get to the cell, IF it wasn't moving away too fast. We decided to commit to it, as there was nothing else going up yet that was within reach in Nebraska. About an hour later, near Naper, we could see the BOMB updraft to our NNE. It had overshooting tops one after the other, and soon we could pick up the Mitchell radio station. Their reporters were watching a tornado with the storm! Oh great --- we are missing the show, we thought. The cell was still a good 60-70 minutes away as we crossed the Missouri into SD. We decided to head east on 46 through Wagoner, and then go north on 37 to Mitchell where we could intercept the storm. The cell was moving NE at 20-25 mph, and we were despondent. If I had only taken the road to Atkinson, I could have been on the Mitchell storm an hour sooner! It seemed like it took forever to try to catch this cell, which was slowly moving away from us as we zigzagged to try to catch it. As we neared our north option, Road 37, another strong cell was developing to our SE, and it was a little closer --- maybe 50 miles away. We were also hearing of new tornado warnings in northeast Nebraska. Now we were REALLY down in the dumps. There seemed to be several tornadic storms, and we were driving and driving with nothing nearby.  

Tornado warnings flew for a cell between Yankton and Vermillion, to our SE, and new huge storm towers were in front of us, to our east. Along 46, near Lesterville, we had a monster updraft to our east, but it was moving quickly north. It was a "Left-mover"! The chances of this becoming tornadic were slim and none, and once again our hopes were dashed and we felt like we would wind up with little or nothing.

It was almost 7 p.m. now, still two hours left until sunset. I elected to head south on 81 towards Yankton, as strong cells were around Yankton. But, there were several cells, and none seemed particularly dominant. Before getting to Yankton, we went east on the road to Volin. This led us to a couple of strong cells, and we could see some lowerings. Finally---things were looking up a bit! Between Volin and Wakonda we were watching three cells, one to the NNW with a good wall cloud, one to the SW with a ho-hum, non-rotating lowering, and a bigger cell just to the east. The cell to the east was raining into the inflow of our wall-cloud storm, and this basically turned the WC storm to mush. But, I think the cool outflow from the east storm helped to energize the southwest cell...or at least gave it a boundary to work on. The southwest cell's updraft was now just to our south and southeast, and was growing very large. We were east of Volin again, west of Highway 19 in Clay County. Within minutes, a strongly rotating wall cloud was just to our northeast, and a couple of slender funnels were approaching the ground! This was only a mile or so away. We cleared some trees and stopped, and watched as funnels kind of danced around with perhaps brief touchdowns, but the main show was the strongly rotating wall cloud. We were getting blasted by strong westerly RFD winds, and Chuck's hat blew towards Iowa.  

After a few minutes and with no tornadoes for the moment, we got back in the van and blasted east and north, towards the wall cloud. Another tornado was forming---a large tornado! This was south of Centerville a few miles. The tornado kicked up some debris, went up a little, and came back down......it seemed a little shy about kissing the earth. We went further north, towards Centerville, and the same tornado, or a new one from the same wall cloud, started to crank up really good. This one was on the ground near Centerville for about 10 minutes, and we watched it from the west side of Centerville as it moved to the northwest, NNW of town. Meanwhile, another wall cloud formed on the east side of the mesocyclone's updraft, to the ENE of Centerville. Suddenly, another elephant trunk-shaped tornado was solidly on the ground to our ENE, at the same time that the old Centerville tornado was moving off to the NW! We tried to go east of Centerville to get a better look at the new tornado, but the road was blocked by a big tree. The house nearby was damaged, and someone drove up and said he had just sold that place a few weeks earlier! I decided to go back to Centerville and then north, but Chuck said that there were now two tornados going at the same time just to our northeast.  We stopped again, and there were actually three tornadoes going at once in the same area!  These again drifted northwest, and we went through Centerville and northward to keep up. We passed a lot of gawkers and went north, as a NEW wall cloud to the northeast began as the old one and its tornadoes fizzled out to the NNW. There was light to moderate rain on us during much of this time, but we were close enough to have a great view of everything that was occurring. Several miles north of Centerville, we had two large tornadoes in front of us at the same time AGAIN, one with the wall cloud to the NNW, and one with the new wall cloud to the NNE. These funnels and tornadoes were mostly skinny and ropy, but would occasionally become a bit fat and start throwing a bunch of debris into the air. Occasionally they would quickly disappear, with new ones suddenly appearing in the same place or not too far away beneath the same wall cloud. Towards 8:45 p.m. we were near Davis. We had passed through at least one minor damage path along the road north out of Centerville, and the sky was now very dark, and the tornado, or tornadoes, were low contrast. Another low storm base loomed to the SW, so we went back south to watch. This cell did not produce any tornadoes that we could see, but it evolved into a beautiful spaceship updraft! And, as we watched from near Lennox, it put on a drop-dead C-G and C-C and multiple-fork dagger lightning display! Mosquitoes were feeding on me, so we went farther north to catch up and to find stronger inflow winds. This was accomplished west of Sioux Falls, and the lightning was even more constant and incredible, and the storm structure even more jaw-dropping! Inflow winds were 30 mph, but, as I was trying to call for motel rooms, we were suddenly getting swamped by heavy rain and strong west winds.  

We went into Sioux Falls, as tornado warnings continued for our vicinity. It was a little nerve-wracking as the wind and rain blew sideways......but the radar showed a primarily linear complex over the city.  

What an unbelievable day.....I have no idea how many tornadoes we saw from this one storm.  Well, I DO have an idea ---- at least 7 or 8.....maybe as many as 9 or 10. I'll figure it out later. Our group went from the depths of despair --- thinking we had royally messed up the chase --- to incredulity and elation --- as the atmosphere suddenly decided that it was showtime, right where we were. Right up until the time that the tornadoes began I was thinking about all of the dumb decisions that I had made that day. They actually weren't dumb, but they seemed to be leading me into a horrible bust on a great tornado day. It was bonafide dumb luck that we
wound up on the Centerville storm. This was about 200 miles from my original target area! By the way, I think it was our Mitchell storm (that we never reached) that went on to wipe out a small town called Manchester, between Huron and Brookings.

Our lucky horseshoe worked again.

I wonder if Chuck's hat has come back down yet.