Heat — Waukesha, Wisconsin

1999-07-29 to 1999-07-31 · Waukesha, Wisconsin

Wider weather episode

The most intense heat wave since the killer heat wave of July 13-14, 1995, struck southcentral and southeast Wisconsin at the end of July, 1999. This most recent heat wave was responsible for directly killing 8 people (heat was the major cause of death), and indirectly killing (heat was a contributing factor) an additional 6 people. Most of these deaths occurred in or near the city of Milwaukee (Milwaukee Co.), possibly due to the fact that Milwaukee registered a minimum air temperatures of 70 degree or higher for the last 11 days of July. In addition, at least 150 people were treated at local hospitals for heat-related exhaustion or dehydration. Meteorologically, high pressure over the southeast U.S. pushed hot, muggy air into southern Wisconsin. Additional moisture was added to the atmosphere by evaporation of moisture from the Mid West corn belt. In fact, the dewpoint at Milwaukee Mitchell Field reached 82 degrees at 1200CST on the 30th, tying the record high dewpoint set back on July 4, 1977. Kenosha (Kenosha Co.) also hit 82 for a maximum dewpoint reading, while Madison (Dane Co.) came in with 79. On July 29th, maximum air temperatures ranged from 93 at the Wisconsin Dells (Columbia Co.) to 99 at Mt. Mary College in Milwaukee County. Minimum air temperatures for the morning of July 30th ranged from 68 in Juneau (Dodge Co.) to 76 at the Charmany Farm in Madison. Maximum air temperatures for July 30th ranged from 95 in Juneau to 104 in Kenosha. The 104 degrees in Kenosha established a new all-time record for that location! Milwaukee topped out at 95 and 99 for the 29th and 30th, respectively, while Madison topped out at 93 and 97. Minimum air temperatures for the morning on the 31st were in the lower 70s.Thanks to the high dewpoint levels, heat index values during the afternoon hours on the 29th and 30th ranged from 110 to 115. However, on the 30th, the city of Fond du Lac (Fond du Lac Co.) had heat indices of 116 to 119 for 3 hours, the city of Racine (Racine Co.) had heat indices of 115 to 119 for 2 hours, and the city of Kenosha had readings of 115 to 125 for 6 hours. Minimum heat indices during the nighttime hours were around 80.In Milwaukee County, the 4 direct heat deaths were: male 45, male 54, male 66, and female 73, all in their home or apartment. There were 6 other indirect heat-related deaths in Milwaukee County; again, all in their home. Other direct heat-related deaths were: in the city of Fond du Lac /male 65/, in Madison /male 53/, in the city of Racine /male 59/, and in the city of Waukesha (Waukesha Co.) /female 79/, all in their home.

Source: NOAA Storm Events Database, event_id 5710002. Narrative written by the NWS forecast office that issued the report.