Eight years ago today, a localized tornado outbreak occurred across central Illinois. Synoptically the setup was pretty classic with the left exit region of the midlevel jet squarely over the area and a deep surface low. However marginal/"just-in-time" moisture was an expected issue with dewpoints only reaching the mid-50's by go time. However with cold air aloft and the excellent kinematics, it was enough. Although, my chase partner and I thought our tornado chances were done for the day when we pulled into the Casey's gas station on IL-116 at the west edge of Hanna City, ahead of the "tail-end Charlie" cell on the next cluster of storms north of the one that would produce the tornado just west of Springfield around the same time. The storm wasn't looking that impressive on radar and our plan was to gas up, get snacks and drinks, and let the storm roll over us, sheltering his car under the gas station canopy if there was hail and then shoot lightning on the back side on the way home (I never uploaded any of the video from before the tornado encounter until now, I'd forgotten how electrified the storm already was at that point).
It was at this point that several things happened in rapid succession. We felt a gust of warm inflow toward the storm still off to our immediate west (when, based on the prior radar presentation, we were expecting cool outflow), which should have been an "Oh s***!" moment but we just kind of shrugged it off "huh, that's interesting." What we didn't know was that the storm had just undergone a constructive cell merger. The radar updated to reveal, while not quite a classic hook on reflectivity, a definite RFD gust front curling back into an inflow notch, with an intense velocity couplet colocated with it, just off to our northwest! Both our cell phones alerted simultaneously with a WEA for a tornado warning, and the town's sirens blared to life! I'll let the video and its accompanying description tell the rest of the story...
I'm conflicted about counting this as my first tornado, since we weren't 100% sure of it in real time, and it cannot be confirmed from my imagery alone due to the intervening tree line at the ground. NWS ILX surveyed a 7.1 mile path of up to EF2 damage from northwest of Trivoli to north of Hanna City that matches up with the time and direction of our view. This was one of three EF2 tornadoes to occur with the event; the best-known is probably the earlier one that occurred near Good Hope.