A tornado warning was issued for northern Winnebago County in northern Illinois early Wednesday afternoon as a storm cell strengthened, moving out of Stephenson County and into northwest Winnebago County. Scattered thunderstorms developed along and ahead of a cold front currently moving through the Stateline. While atmospheric conditions were not favorable for long-lived, long-tracked tornadoes, there was just enough veering of the wind field (turning winds with height) right along the front to cause the storm to begin to rotate.
Meteorologist Joey Marino was out watching the storm as it moved north of Ridott (Stephenson County), and east towards Durand. It was at that time he noted the storm did begin to develop a wall cloud with very slow rotation, as well as quite a bit of inflow (warm, moist air moving into the storm itself). Shortly after, a tornado warning had been issued for northern and northeast Winnebago County based on radar rotation within the storm.
Joey did witness a couple funnel clouds but they were higher up and there didn’t appear to be any ground circulation or debris. The funnels were also quick to evaporate. As the storm moved into northeast Winnebago County it did begin to weaken, but continued to show a little broad rotation with it. Gusty winds from the outflow boundary also kicked up quite a bit dust, with winds gusting 40-50 mph.
As we head further into Wednesday evening our risk for strong to severe thunderstorms remains low. However, scattered thunderstorms will continue through sunset across northern Illinois and southern Wisconsin. A cluster of storms currently moving into northwest Illinois are capable of producing torrential downpours, as well as 30 mph wind gusts. This particular storm will move into northwest Carroll County from near Savanna to Mount Carroll. It is currently move east at 30 mph.