Excessive Heat — Kewaunee, Wisconsin

2025-06-21 to 2025-06-23 · Kewaunee, Wisconsin

Event narrative

The combination of hot temperatures and high humidity caused heat index values to rise as high as 107 degrees during the late afternoon on Saturday and 106 degrees Sunday afternoon.

Wider weather episode

A warm front lifted north through the region late Friday night (6/20) into early Saturday morning (6/21) allowing daytime temperatures to soar into the lower to middle 90s with dew points in the middle to upper 70s Saturday (6/21) and Sunday (6/22) afternoon. The high of 94 at the Green Bay Airport on Sunday (6/22) tied the record high for the day. The combination of hot temperatures and high dew points allowed heat index values to soar to 105 to 110 degrees both days. Temperatures on Monday (6/23) again soared into the lower 90s with dew points in the lower 70s, pushing heat index values to 100 to 105 degrees. Several highways buckled due to the extreme heat on Sunday (6/23).

In addition to the hot temperatures, overnight lows only fell into the upper 70s Saturday night (6/21) into early Sunday morning (6/22) as well as Sunday night (6/22) into early Monday morning (6/23), providing minimal relief from the hot temperatures. The warm overnight temperatures set or tied new records for record high minimums across much of the area for Sunday (6/22). The high minimum values on Sunday (6/22) of 79 in Green Bay, 78 in Wausau, and 76 in Rhinelander each tied the all-time highest minimum temperatures on record for those locations. The heat wave broke when a cold front moved through the area Monday afternoon and evening (6/23) along with showers and thunderstorms.

Source: NOAA Storm Events Database, event_id 1255142. Narrative written by the NWS forecast office that issued the report.