A supercell spins in west-central Illinois near Kirkwood, IL
On May 11th, Vicky and I ended up chasing in southeast Iowa and west-central Illinois. This day featured a whole lot of tornado potential from southeast Nebraska stretching east through southeast Iowa. We couldn't make it out to the Nebraska target on this chase day due to a late start so we decided to chase somewhat locally seeing potential for a tornado report or two in southeast Iowa or west central Illinois along a warm front. The area we targeted in southeast Iowa along the warm front featured 2,000J/kg of CAPE, 0-6km shear at 40kts, a supercell composite of 8, and a moistening boundary-layer along the warm front with dew points near 67°F. By early afternoon, severe thunderstorms including an elevated supercell had initiated along the warm front in Iowa. This storm would continue to develop and we decided initially to chase this supercell as it moved toward our location outside Mt. Pleasant, IA along U.S. 218. Despite this being a tornado-warned supercell it was rather obvious visually that it was elevated so we decided to move back east along U.S. 34 to catch some new supercells developing along the warm front as they moved northeast toward Burlington, IA and Monmouth, IL. We were quite interested in a supercell near Burlington, IA and positioned just east of the Mississippi River to catch this supercell. While positioning for that storm supercells began to develop nearly overhead along the warm front. We caught the backside of one of these supercells near Kirkwood, IL along U.S. 34. It surely had some rotation as it was tapping surface-based instability to its immediate south as well. We ended up quickly pulling off the highway to escape some hail about a mile up the road. We snapped a few photos as the mesocyclone began to tighten a little bit nearly dropping a nice cone funnel within a mile of our location. It really was teasing us at this point! Unfortunately, it just wasn't enough as cool rain-cooled air wrapped into it chocking it off from the north. Yet, it still was quite photogenic! We would later talk to another spotter in this area informing us that the storm we were waiting to cross the river near Burlington, IA had a brief tornado reported with it. Damn rivers! Storms never seem to tornado where you want them too! We turned around and headed toward this once supercell, but it had quickly fizzled out as it crossed the Mississippi River. We then waited for storms to congeal to our north and they did just that providing a rather picturesque shelf cloud near sunset in west-central Illinois. After that we called it a chase after grabbing some dinner. I've added photos from the chase day below:
Backside of this supercell providing some great contrast!
A beautiful storm on this late-afternoon!
Would of made a much better photo with a cone in it! Mother Nature's way of trolling I guess...
"Spin and Twist"
It didn't produce, but a nice catch though!
Everybody likes a selfie well how bout a "shelfie"...
That will end this chase post. This was a rather fun chase! We didn't grab a tornado on this day, but it wasn't for a lack of trying and good forecasting. We targeted the right area locally since we couldn't make it to southeast Nebraska so I can't complain at all. I also chased the following day on May 12th as well. I'll update soon with that post as well.
