Walker's Travels: 5/22/2010 -- South Dakota Supercells and EF4 Bowdle Tornado

Saturday was an almost perfect storm chasing day ... it featured a plain-as-day target, multiple tornadoes, and simply amazing storm structure. The day began (early) in Alliance, NE, which meant I needed to cross the Nebraska Sandhills and half of South Dakota to reach my target region of north-central South Dakota -- an area that was forecast to experience huge CAPE and nice backed winds ahead of a surface low. I was a bit fearful I had to travel too far and may be late to the show, but the timing was (luckily!) perfect. As I neared by target region north of Pierre, SD, I witnessed the initial cu bubbling northeast of the Lake Oahe area. The cu continued to grow and, after a bit, exploded in the rural Lowry, SD region. As I approached from the south, the first tornado warning was issued.

Initial cu well north of Pierre, SD

Storm goes tor-warned as I approach from the south.

I was a bit unsure of storm motion early on, so I continued north and then scooted east on SR-20, and then north (on a dirt road) toward Lowry. I slipped under the dramatic wall cloud for a few, where I witnessed a funnel to my immediate north. I high-tailed it east along back roads north of Swan Lake where I witnessed one of the weirdest scenes ever -- huge, towering swarms of bugs that almost appeared as though little miniature tornadoes everywhere. My brain was confused for a second --are these lil' tornadoes starting up? -- it was like a scene out of Lost with smoke monsters coming out everywhere. Dead calm at this time under the rotating wall cloud. Weird! I only wish I had the time to stop and take a picture of this weirdness. I'm sure it will reappear in a nightmare in my future.

As I moved onto payment (thankfully!) on SR-47, it was quite evident that the wall cloud to my west-southwest was getting real mean, real quick. I goosed up into the notch -- north on SR-47 -- so as to get ahead of the imminent tornado by taking US-20 east. I was about three miles south of US-20 when the thing dropped -- a couple times. Hard to drive and take pics at the same time -- but I wasn't about to slow down, jump out, and take a few leisurely pics. This thing was looking nasty and heading for me. Cloud motion in the wall was extreme, which meant this thing was gonna go big. I made it up to US-20 and then east a few miles -- at this point, I was safe and was afforded the rather amazing perspective to watch the tornadoes dance and congeal into a large, EF4 wedge as it crossed 20 to my west. I sat for a bit, but eventually moved east down US-20 so as to stay ahead of the trail of chasers and to get some structure shots. This was a good decision as I was able to gather the entire storm structure -- as well as tornado -- into my viewfinder. For this structure freak, it was heaven.

One of the initial tors -- wide angle perspective. Not sure I have pics of the first tornado or two -- too busy trying to get to the north and east during that time.

Getting ready to drop the monster.

Wedge commences ...

Sorry for all those pics -- I just love storm structure!

Anyway, I stayed with the storm for a while, stopping intermittently along US-20 and then just a bit north of Roscoe. The wedge eventually dissipated north of Bowdle, but the storm went on to produce a couple more tornadoes to the northwest of Roscoe. Eventually, I could tell the thing was getting more and more HP, so I broke off and headed south to intercept new storms firing.

Storm cycles northwest of Roscoe.

A couple more tornadoes formed before it trended toward an HP beast.

Last tor from my perspective. Rain wrapped hereafter -- so I headed south for "new" storms.

Storm transitions to an HP bomb -- note the notch and inflow. I would have headed northbound at this time, but I didn't like my road options up there.

These (secondary) storms were visually spectacular! As the gif animation below illustrates, at one time, the storms appeared to be spitting out these little mesos. Truly phenomenal structure to witness.

How cool are those things!?

After sitting for a bit, I raced east as the storms tended to line out and was treated to a nice laminar banded, zit-filled show toward sunset. Despite having a pheasant splatter across my windshield and almost running into a bunch of loose black cows on a dark, dirt road ... the day was about as fulfilling as any storm chasing day I've experienced. I'm thankful no injuries occurred in this event. The towns of Bowdle and Roscoe were very lucky on this Saturday in May.