Elevated threat of tornadoes detected for Wednesday, June 17th, 2026.
See attached map for details.
This forecast initialized on Tuesday afternoon. Follow for future forecast updates.
Elevated threat of tornadoes detected for Wednesday, June 17th, 2026.
See attached map for details.
This forecast initialized on Tuesday morning. Follow for future forecast updates.
Potential Tropical Cyclone #One Advisory 1 (10 AM CDT, Tue Jun 16): Very Heavy Rainfall and Dangerous Flash Flooding Expected from Potential Tropical Cyclone One. https://t.co/tW4KeGdBFb
It's soundings like this that spooks me the most. Pushing the edge of what's possible given a parcel of air is buoyant. Not robustly buoyant, but can be buoyant with the right lift. These types of very saturated/weakly thermodynamic and bonkers level hodographs, can generate strong, intense, and violent tornadoes. Wherever this boundary migrates northward will be a serious risk for EF-3+ tornadoes.
One such case that comes to mind is the Nashville, TN EF-3 and Cookeville, TN EF-4, where a weakly thermodynamic environment was paired with a very intense LL shear environment.
From a chasing standpoint, you essentially need to get in the bears cage of a 60 mph moving tornado to have any hopes of seeing this. You are essentially disaster chasing. Do with that as you will.
This isn't to spark fear, but rather inform of all the potential on the table, and if it were me, a tornado-driven high-risk upgrade 'should' be on the table. We have a lot to figure out, but surely, this may be an event worth considering the upgrade.
There is also the possibility, appearing maybe less likely, that most of the warm sector storms become a tad far removed from the better shear overlap, something SPC already laid out with the core of the LLJ more to the Northeast, so we may end up with a string of supercells, given the ambient 50-60 kts of bulk shear perpendicular to the boundary, that grow more tornadic with eastward extent. I think this is a possible outcome, but the probability is unclear. This would be the best-case scenario for folks living in the region. Minimize the tornado threat to a corridor rather than a large spatial area.
Regardless, it appears now to look primed and ready for a potential tornado outbreak across MO/IL/IN, maybe including a couple of tornadoes in IA/MN/WI.
Area-averaged sounding taken from NW Indiana tomorrow. Cookeville, TN, reanalysis sounding taken from the retired US tornado case archive.