A continuation of above normal temperatures and lack of rainfall contributed to a deterioration of drought conditions across central Iowa. Severe Drought developed early in the month in portions of Dallas, Polk and Jasper counties.
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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 DMX wrote it up.
A continuation of above normal temperatures and lack of rainfall contributed to a deterioration of drought conditions across central Iowa. Severe Drought developed early in the month in portions of Dallas, Polk and Jasper counties. This was an expansion of a much larger area of severe or worse drought conditions over a large portions of central Iowa. Agricultural crops were mainly unaffected by this point in the season as many of the crops had already reached maturity. However, the drier conditions did hasten the dry down of crops with harvest in full swing by the end of the month.
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 Des Moines, IA wrote its last area forecast discussion before the first event at Sep 5, 5:37 AM CST, 1 hour 23 minutes earlier.
Area Forecast Discussion National Weather Service Des Moines IA 637 AM CDT Tue Sep 5 2023 ...Updated for the 12z Aviation Discussion... .DISCUSSION.../Today through Monday/ Issued at 319 AM CDT Tue Sep 5 2023 Key Messages: - Final hot day of the latest heat wave today with heat index approaching 100 central and east. - Storms this evening as a cold front moves across the area. A few stronger storms are possible. - Cooler through the end of the week with highs in the 70s to low 80s. Discussion: Quiet conditions across much of Iowa overnight as low level jet orientation has favored thunderstorms remain just west of the area thus far. Over the next few hours there is a chance that a stray storm or two may graze far southwest portions of the area per trends in recent CAM runs. Otherwise, expect today to be the final hot day of the latest late summer heat wave, with heat indices this afternoon forecast to approach 100 degrees across much of central and eastern Iowa. The heat will be accompanied by breezy south winds this afternoon as deep mixing develops once again into the afternoon. On our doorstep, however, is an approaching cold front which will move across the area this evening. Environmental parameters are better north into Minnesota and in Iowa will depend on whether we can mix out the cap most soundings show across the area. For any convection that does develop, expect wind to be the primary severe hazard with deep inverted-V characteristics in model soundings. Best placement for any thunderstorms activity would begin across central Iowa, with chances increasing into eastern Iowa later in the evening as the low level jet helps sustain convection. Wednesday will remain breezy, but much cooler as temperatures remain mainly in the 70s across the area. With a transition to northwest flow, RAP indicates smoke will curl around to the area so anticipate hazy skies on Wednesday. Cooler temperatures in the 70s to low 80s will last through the rest of the week with no precipitation chances to speak of. Next chances for rain are not expected to arrive until the upcoming weekend. && .AVIATION.../For the 12Z TAFS through 12Z Wednesday morning/ Issued at 636 AM CDT Tue Sep 5 2023 Winds out of the south to southwest will gust 20 to 25 kts through this afternoon. By evening expect scattered thunderstorms to develop with a cold front moving across the area. Due to the scattered nature of anticipated storms, confidence in impacts to KFOD/KMCW/KALO is somewhat decreased. Further south towards KDSM there convection should diminish, so have included just a VCSH mention. This will be fine tuned thorugh the day. Otherwise, following the storms, frontal passage will result in a wind shift to out of the northwest by Wednesday morning. && .DMX WATCHES/WARNINGS/ADVISORIES... NONE. && DISCUSSION...Hagenhoff AVIATION...Hagenhoff
Hazardous Weather Outlook National Weather Service Des Moines IA 346 AM CDT Tue Sep 5 2023 IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075- 081>086-092>097-060900- Emmet-Kossuth-Winnebago-Worth-Palo Alto-Hancock-Cerro Gordo- Pocahontas-Humboldt-Wright-Franklin-Butler-Bremer-Sac-Calhoun- Webster-Hamilton-Hardin-Grundy-Black Hawk-Crawford-Carroll-Greene- Boone-Story-Marshall-Tama-Audubon-Guthrie-Dallas-Polk-Jasper- Poweshiek-Cass-Adair-Madison-Warren-Marion-Mahaska-Adams-Union- Clarke-Lucas-Monroe-Wapello-Taylor-Ringgold-Decatur-Wayne- Appanoose-Davis- 346 AM CDT Tue Sep 5 2023 This Hazardous Weather Outlook is for portions of central Iowa. .DAY ONE...Today and tonight Thunderstorms are possible, mainly late today and into this evening. A few strong storms may occur over far north central Iowa and also areas east of Interstate 35. Damaging wind gusts over 60 mph and quarter sized hail are the primary threats. .DAYS TWO THROUGH SEVEN...Wednesday through Monday A few storms are possible Sunday and Monday. The threat for severe weather will continue to be accessed this week. .SPOTTER INFORMATION STATEMENT... Spotters may be needed briefly this afternoon and evening.
The national radar mosaic for the moment the first event began.
3 drought. Local standard time, as filed.
Severe drought conditions expanded into Dallas county in early September as above normal temperatures and below normal precipitation persisted into the month.
Severe drought conditions expanded into Polk county in early September as above normal temperatures and below normal precipitation persisted into the month.
Severe drought conditions expanded into Jasper county in early September as above normal temperatures and below normal precipitation persisted into the month.
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, September 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 2026-09-24. Each event’s entry at NCEI: 1139691, 1139692, 1139693.