June 6, 2020
Statistics
Initial Target
Start
End
Storm Intercepts
Tornadoes
Hail
Wind
Features
Miles
Sioux Falls, SD
Springfield, IL 11:35 AM 6/5/2020
Sioux Falls, SD 2:35 AM 6/7/2020
Dell Rapids, SD
0
0"
0 mph
Updraft Base
762
Summary
Slight risk long odds warm front play in southeast South Dakota. Warm sector failed to initialize so briefly chased elevated yet pretty storm north of the warm front near Dell Rapids.
Crew and Equipment
Chase partners: Jennifer Brindley Ubl. Equipment: Sony FDR-AX100.
Video
Details
"Day 1 Today: Targets and setup outlined yesterday remain. There are 3 main tornado targets I'm focused on at the moment: 1. Far northwest SD maybe even into MT. West of the higher 700 mb temps hopefully, with some lower LFC and LCL heights making for some low level CAPE. A bit worried you're just going to see hailers with big cold pools out that way. I'd probably put the highest overall tor probs on this target, but it has the lowest payout.
2. Laramie, se into CO. Still seeing that 0-3km CAPE bubble and strong dynamic forcing for the full strength of that shortwave could get a small/mini-sup spinning up a tornado in the mountains or adjacent plains.
3. Well down the warm front in central to eastern SD. Getting away from the better upper level shear here, so lift and excessive capping are all major problems. These storms tracking through Nebraska and a bit of showering action up in South Dakota are a big wild card. I'm watching that closely to put down an outflow boundary that could air in late afternoon/evening initiation of more robust, hopefully surface based storms. Three recent runs of the HRRR had this happening near the Sioux area. Thermodynamics may yet preclude a sig tornado play, but the low level speed and directional shear is otherwise extremely favorable, and coupled with some extreme instability... something big is possible. Long odds, high risk of bust, highest payout gamble.
Kind of a fourth target... Still seeing helicity tracks through Rapid too, but worried that's going to be mainly an MCS with early initiation in WY and taking hours to make it northeast to Rapid. Those storms are going to be difficult to track through the Black Hills and road holes north of Rapid. You'd have a couple of shots to intercept right in Rapid or unless you get lucky and it tracks right up the highway to Mud Butte. "
Exiting at Dell Rapids we watched flat updraft bases with sculpted downdraft cuts and plumes of dust being kicked up by outflow winds. There was some sort of interesting wave pattern running down the flanking line to the south with these repeating circulations.
Conclusion
The high risk, high reward play didn't pay out this time, but we thought it was worth a shot. The elevated storm was pretty and with interesting structure too. We were out for the next day as well, so more chances awaited.
Lessons Learned