Flash Flood — Carroll, Illinois

2022-08-19 to 2022-08-20 · near Chadwick, Carroll, Illinois

Event narrative

Law enforcement reports that Otter Creek is out of its banks over Telegraph Road, near the intersection with Elm Road. Also 2 bridges north of Highway 52, near Lanark are also about to be covered by water from Saddle Creek.

Wider weather episode

A cold core low moved over the area, dragging along a weak and slow moving surface low. Although weak, sufficient low level and upper forcing aided in developing strong to severe storms. Instability and shear were strong enough for a few supercell thunderstorms to develop and bring hail, strong winds, and heavy rain to the area. The storms were slow moving. which allowed some storms to anchor over locations for an extended period of time, resulting in flash flooding. Some repeated storms over the same area also led to similar results. Severe weather reports were mostly in the form of hail, as these storms produced hail very efficiently. The largest hail reported was 1.5, and there were some isolated reports of damaging winds.

View location on OpenStreetMap → (42.0200, -89.8100)

Source: NOAA Storm Events Database, event_id 1052925. Narrative written by the NWS forecast office that issued the report.