Strong high pressure and elevated near surface moisture resulted in a multi-day heat wave across southeast South Dakota, southwest Minnesota, northwest Iowa, and northeast Nebraska from July 25-28. With air temperatures rising into the 90s and low 100s and dewpoint temperatures in the 70s and low 80s, afternoon and evening heat indices generally peaked from 100 to 120 degrees with little…
Every event with a place to put it; 11 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 FSD wrote it up.
Strong high pressure and elevated near surface moisture resulted in a multi-day heat wave across southeast South Dakota, southwest Minnesota, northwest Iowa, and northeast Nebraska from July 25-28. With air temperatures rising into the 90s and low 100s and dewpoint temperatures in the 70s and low 80s, afternoon and evening heat indices generally peaked from 100 to 120 degrees with little overnight recovery. The most widespread opressive conditions occurred during the afternoons and evenings of July 26 and July 27.
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 Sioux Falls, SD wrote its last area forecast discussion before the first event at Jul 25, 5:31 AM CST, 4 hours 29 minutes earlier.
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<title>Service Notice</title>
<link rel="stylesheet" href="index.css">
</head>
<body>
<main class="wrap">
<section class="card" role="status" aria-live="polite">
<div class="status" id="status">Temporary Notice</div>
<h1 id="headline">This service is currently unavailable.</h1>
<p id="message1">
The site you requested is temporarily down for maintenance or an unexpected outage.
</p>
<p id="message2">
Please try again in a few minutes.
</p>
<p class="small" id="detail">
If you are an administrator, restore upstream service and remove the redirect/fallback rule when normal operations resume.
</p>
</section>
</main>
<script src="index.js"></script>
</body>
</html>Hazardous Weather Outlook National Weather Service Sioux Falls SD 452 AM CDT Tue Jul 25 2023 IAZ001>003-012>014-020>022-031-032-MNZ071-072-080-081-089-090-097- 098-NEZ013-014-SDZ038>040-052>056-058>062-064>071-261000- Lyon-Osceola-Dickinson-Sioux-O'Brien-Clay-Plymouth-Cherokee- Buena Vista-Woodbury-Ida-Lincoln-Murray-Cottonwood-Nobles-Jackson- Pipestone-Rock-Dixon-Dakota-Beadle-Kingsbury-Brookings-Jerauld- Sanborn-Miner-Lake-Moody-Aurora-Davison-Hanson-McCook-Minnehaha- Douglas-Hutchinson-Turner-Bon Homme-Yankton-Union- 452 AM CDT Tue Jul 25 2023 This Hazardous Weather Outlook is for northwest Iowa, west central Iowa, southwest Minnesota, northeast Nebraska, central South Dakota, east central South Dakota, south central South Dakota and southeast South Dakota. .DAY ONE...Today and tonight. There is a chance for some strong to severe thunderstorms to begin late Tuesday afternoon and continue through the evening. Storms will move from the northwest to the southeast beginning around Huron and continuing through Sioux City. These storms are most likely to begin as scattered thunderstorms capable of producing hail 1.5 to 2 inches, and damaging wind gusts. As they progress, the threat will transition from hail to strong wind gusts 60 to 65 mph. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Heat continues across the region Thursday. Heat indices may top 100 degrees, in localized areas through the Missouri River Valley on Tuesday, then becoming more widespread by Wednesday and Thursday. Prepare now to ensure you are ready for the combination of dangerous heat and humidity. There is a chance of thunderstorms Thursday night. While the risk of severe weather is low, a few stronger storms are possible, with hail and gusty winds as the primary threats. .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected at this time. SDZ050-057-063-261000- Gregory-Brule-Charles Mix- 452 AM CDT Tue Jul 25 2023 This Hazardous Weather Outlook is for south central South Dakota. .DAY ONE...Today and tonight. Highs in the mid to upper 90s coupled with dew points in the upper 60s to 70s will result in heat indexes breaching 100F. Prepare now to ensure you are ready for the combination of dangerous heat and humidity. There is a chance for some strong to severe thunderstorms to begin late Tuesday afternoon and continue through the evening. Storms will move from the northwest to the southeast. These storms are most likely to begin as scattered thunderstorms capable of producing hail 1.5 to 2 inches, and damaging wind gusts. .DAYS TWO THROUGH SEVEN...Wednesday through Monday. Heat continues across the region Thursday. Heat indices may top 100 degrees, in localized areas through the Missouri River Valley on Tuesday, then becoming more widespread by Wednesday and Thursday. Prepare now to ensure you are ready for the combination of dangerous heat and humidity. There is a chance of thunderstorms again Thursday night. While the risk of severe weather is low, a few stronger storms are possible, with hail and gusty winds as the primary threats. .SPOTTER INFORMATION STATEMENT... Spotter activation is not expected at this time.
The national radar mosaic for the moment the first event began.
11 excessive heat. Local standard time, as filed.
Daily afternoon and evening heat indices ranged from 100 to 113 degrees with a maximum heat index of 113 degrees at the Iowa Department of Transportation site near Storm Lake on July 26.
Daily afternoon and evening heat indices ranged from 100 to 118 degrees with a maximum heat index of 118 degrees at the nearby South Dakota State University mesonet site near Baltic on July 27.
Daily afternoon and evening heat indices ranged from 100 to 111 degrees with a maximum heat index of 111 degrees at the Automated Weather Observation System site at the Sheldon Regional Airport on July 26.
Daily afternoon and evening heat indices ranged from 100 to 119 degrees with a maximum heat index of 119 degrees at the Remote Automatic Weather Station site near Elk Point on July 26 and July 27.
Daily afternoon and evening heat indices ranged from 100 to 114 degrees with a maximum heat index of 114 degrees at the Automated Weather Observation System site at the Sioux County Airport (KSXK) on July 27.
Daily afternoon and evening heat indices ranged from 100 to 120 degrees with a maximum heat index of 120 degrees at the Iowa Department of Transportation site near Moville on July 27 and July 28.
Daily afternoon and evening heat indices ranged from 100 to 111 degrees with a maximum heat index of 111 degrees at the Automated Weather Observation System site at Cherokee Regional Airport (KCKP) on July 28.
Daily afternoon and evening heat indices ranged from 100 to 111 degrees with a maximum heat index of 111 degrees at the Iowa Department of Transportation site near Spencer on July 26.
Afternoon and evening heat indices ranged from 100 to 111 degrees with a maximum heat index of 111 degrees at the nearby Minnesota Department of Transportation site near Lakefield on July 26.
Afternoon and evening heat indices ranged from 100 to 112 degrees with a maximum heat index of 112 degrees at the Iowa Department of Transportation site near Ida Grove on July 28.
Afternoon and evening heat indices ranged from 100 to 109 degrees with a maximum heat index of 109 degrees at the Iowa Department of Transportation site near Sibley on July 26.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Iowa in 2023Every state in 2023This day in weather historyWarnings in Iowa, July 2023
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: 1128509, 1128521, 1128526, 1128530, 1128533, 1128534, 1128511, 1128515, 1128516, 1128519, 1128529.