Decided to chase a marginal day in Southern IL for supercells and possible tornadoes along a warm frontal boundary. SPC went with “enhanced risk” probabilities on this day noting large hail and isolated tornadoes as the main risks. Instability was forecast initially to be quite strong (~3000 J/KG) however early day convection limited this to more in the way of (~1000-1500 J/KG). However with 50 knots of deep layer shear this was still sufficient to produce a severe thunderstorm and transient supercell from Thompsonville, IL to near Corydon, KY. The storm exhibited greatest rotation near the Thompsonville area where we observed strong low level rotation in what appeared to be the “inflow notch” region of this storm. Surface inflow was great however despite this, the storm fought outflow characteristics and high precipitation nature reducing any tornado threat that would have otherwise existed. ***I should note NWS Paducah is reviewing the Thompsonville area for a possible tornado touchdown, nothing is conclusive yet though***.
SPC Day 1 outlook
Here are a few images that I shot during the storm’s life. I caught this cell near Thompsonville south of I-64 and followed it into Western Kentucky. Low level structure was decent enough at times and we encountered sub-severe (~50 MPH) winds and marginal hail (0.88-1.00″) near Morganfield, Kentucky before heading home.
Wide angle shot of the HP storm near Thompsonville, IL.
Thompsonville, IL wide angle shot. Low level Rotation ramping up on the left side of the image
Close up shot (85mm) of the rotation developing near Thompsonville, IL
Wide angle shot of the HP storm west of Morganfield, KY
Morganfield, KY HP storm.
