The flow around an area of high pressure over the eastern Great Lakes and ahead of an area of low pressure over the Northern Plains brought hot and humid conditions to parts of southwest Wisconsin July 27th. The apparent temperature at La Crosse (La Crosse County) and Prairie du Chien (Crawford County) topped out at or above 105 during the afternoon.
Every event with a place to put it; 2 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS ARX wrote it up.
The flow around an area of high pressure over the eastern Great Lakes and ahead of an area of low pressure over the Northern Plains brought hot and humid conditions to parts of southwest Wisconsin July 27th. The apparent temperature at La Crosse (La Crosse County) and Prairie du Chien (Crawford County) topped out at or above 105 during the afternoon.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS La Crosse, WI wrote its last area forecast discussion before the first event at Jul 27, 8:18 AM CST, 4 hours 27 minutes earlier.
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</html>The national radar mosaic for the moment the first event began.
2 heat. Local standard time, as filed.
The combination of the temperature and dew point measured by the automated weather observing equipment at the Prairie du Chien airport created a maximum heat index of 106.
The combination of the temperature and dew point measured by the automated weather observing equipment at the La Crosse airport created a maximum heat index of 105.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wisconsin in 2010Every state in 2010This day in weather historyWarnings in Wisconsin, July 2010
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-10-01. Each event’s entry at NCEI: 249231, 249232.