Thunderstorm Wind — Waseca, Minnesota

2023-07-27 · near Janesville, Waseca, Minnesota

Event narrative

Strong thunderstorm winds brought down a 10-inch diameter tree limb which blocked a roadway in Janesville, MN.

Wider weather episode

Prolonged hot and humid conditions coupled with dry mid-levels in the atmosphere, led to extreme amounts of mixed-layer convective available potential energy (MLCAPE). The existence of deep layer shear allowed for numerous strong updrafts to develop across East Central MN with the primary hazard being hail in the afternoon hours. Later that evening in Southwestern MN, a surface boundary would converge on a cold pool which then would produce a line of thunderstorms capable of producing damaging wind gusts.

Hail measurements ranged between penny (0.75 inch) to Hen-Egg (2.0 inch) size. The highest measured hail was reported in the city of Morgan, MN or 13 miles SE of Redwood Falls located in Redwood County.

Strong winds uprooted trees, broke large tree branches across much of the region affected by these storms. The areas with the most damage occurred in Chisago County as well as a line from Nicollet to Waseca Counties. The strongest gust (57 mph) was recorded at 11:56 PM at the Mankato Regional Airport.

View location on OpenStreetMap → (44.1200, -93.7100)

Source: NOAA Storm Events Database, event_id 1119818. Narrative written by the NWS forecast office that issued the report.