June 7, 2020
Statistics
Initial Target
Start
End
Storm Intercepts
Tornadoes
Hail
Wind
Features
Miles
Jamestown, ND
Sioux Falls, SD 9:51 AM 6/7/2020
Springfield, IL 10:28 PM 6/8/2020
Kulm, ND
0
0"
0 mph
Possible Funnel, Wall Cloud, RFD Clear Slot
1315
Summary
Dryline setup in central ND. Targeted Jamestown for evening tornadic supercells. Intercepted tornado warned cell near Kulm noting possible funnel cloud and scud look-a-like tornado. Chased second storm noting block wall cloud structure.
Crew and Equipment
Chase partners: Jennifer Brindley Ubl. Equipment: Sony FDR-AX100.
Video
Details
"Day 1 Today: Hemming and hawing on the targets here, but still leaning on Jamestown, ND 22 to 0z/5 to 7pm. Was looking hard at the warm front in far northwest Minnesota. CAMs consistently initiate supercells on it, and the directional shear is maximized up there. However, I'm worried that the air aloft is still quite warm and formidable cap exists on the cool side of the boundary. Midlevel flow is perpendicular to the boundary. So I'm worried that even if storms go up south of the boundary, they're going to quickly cross the front and head into an elevated environment. It's just close enough to the trees and Canadian border, that I'm also worried that the storm could escape and leave you stranded. Would not at all be surprised to see some stovepipes reported just north of Thief River Falls. If you're playing that target, you're hopefully already moving on it. Expect that show to go a little earlier than the other plays, say midafternoon. Capping and low level instability looked maxed at 21z with the cap filling in by 0z.
Otherwise there's a moist axis running southwest from that target down across the Missouri River in central SD. I expect that to erupt like a dryline per CAM guidance. Signal has been consistent on an evening initiation of 22z with mature storms by 23z. Flow isn't quite so southerly so not expecting storms to back up as badly into an MCS. Yet that's what the CAMs show, upscale growth and a large MCS forming by evening. Good model agreement on the HRRR, RAP, and NAM on a 0-3km CAPE pool lifting from the Pierre area now into south central ND by evening. That would be my focus for getting a tornado today. Worried that cells to the south might interfere with a cell trying to hold out for better shear later when the low level jet ramps up or as it makes for more backed winds to the northeast. Kind of bummer we're not seeing the nice backed winds along 94 atop the surface trough, but the warm sector is just generally veered southerly surface flow until you get to the warm sector. That's keeping the helicity modest across the Dakotas until evening when the low level jet ramps up. But hopefully there is a window of opportunity for a discrete supercell to organize in decent shear around that 23z to 0z time frame before it's interfered with or the inhibition starts to fill back in. So that's my thi
There's a secondary target: play down the line say east of Pierre, SD. Rocking low level jet, winds are a bit more backed at the surface, and a more discrete Tail End Charlie. It looks great supercell wise, but the models say the low level instability is absent due to high LCL and LFC heights, and large T/Td spreads may otherwise preclude the sig. tornado show here. Tornado still possible here, especially the dust whirl or embedded circulation kind, but I'd put the the higher tornado probs to the north just because of the thermodynamics. Probably the best structure play is here.
UPDATE: Noted SPC putting all 10 hatched chips on the Thief River Falls bet. Hemming and hawing intensifies. "
We intercepted an organizing supercell near the town of Kulm. We missed a brief tornado, but the storm still looked promising with a scuddy funnel on the north side of the horseshoe.
Conclusion
We couldn't pull off the tornado shot on this Plains run, but the supercell catch was dramatic and photogenic nevertheless.
Lessons Learned