Intense heat and low precipitation led to continued expansion of severe drought over portions of Iowa.
Every event with a place to put it; 9 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 DMX wrote it up.
Intense heat and low precipitation led to continued expansion of severe drought over portions of Iowa.
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 Aug 29, 5:06 AM CST, 1 hour 54 minutes earlier.
Area Forecast Discussion National Weather Service Des Moines IA 606 AM CDT Tue Aug 29 2023 ...Updated for the 12z Aviation Discussion... .SHORT TERM.../Today through Wednesday/ Issued at 250 AM CDT Tue Aug 29 2023 Forecast Impacts for the week: ...Seasonal and dry most of week ...90s return Friday into Weekend ...Heat lingers into early next week Confidence Short Term: High A weak boundary is entering northern Iowa at 05z with patchy clouds in northeast Iowa. Ahead of the front, southwest winds continue at 5 mph while behind the front, winds are now northwest at 5 mph. Another weak system is located in southern Canada with a trailing front over North Dakota. Today will see an increase in wildfire smoke/haze aloft and have continued the trend to add that to the forecast through Wednesday. The HRRR smoke model keeps the area tracking into and about the state through at least 00z Thursday. Today will be mild again with afternoon highs in the lower 80s north to mid 80s across the remainder of the region. With high pressure building south into Wisconsin tonight and early Wednesday, a renewed push of cooler air will move into the region tomorrow. This will keep overnight lows in the lower to mid 50s northeast tonight and in the upper 50s central to south tonight. Highs Wednesday will be pleasant with light east winds becoming more southeast over the west by afternoon. Highs will be comfortable tomorrow in the upper 70s north to the lower 80s south. && .LONG TERM.../Wednesday Night through Monday/ Issued at 250 AM CDT Tue Aug 29 2023 Confidence: High For now, the west northwest flow aloft will continue through Wednesday night, then as an area of low pressure tracks through the Northern Rockies, we will see a shift to more west southwest winds aloft. Much warmer air which continues over the southwest/west will gradually shift into the area as we move into later Thursday and Friday. The Great Lakes high will hold on into Thursday and provide the region with another banner day. H850 temperatures warm to the mid teens over the region with upper teens just entering far western Iowa. This will keep afternoon highs in the comfortable range and generally in the lower 80s over the forecast area. The impacts of the approaching Northern Rockies low will be felt from Friday into the holiday weekend. By later Friday, H850 temperatures will warm to the upper teens on our eastern border with lower 20s over the west. Thus a return to afternoon highs near 90 west is anticipated Friday afternoon with a few other areas that remain rather dry, also nearing 90. Warm air advection will increase Friday night into Saturday with southwest flow increase to 10 to 15 mph overnight and likely seeing a more brisk 15 to 25 mph wind on Saturday with the higher winds over the west/northwest. Along with H850 temperatures now in the mid 20s over most of the area, highs will vault into the lower to mid 90s. Little change is expected for Sunday into Monday with a general lack of moisture return until later Monday afternoon. For Saturday and Sunday, we remain capped aloft with H700 temperatures around 14C and little forcing in the immediate area. Dew points Saturday into Sunday should remain in the 50s to lower 60s in the afternoon hours. This will put a cap on heat indices, keeping them closer to afternoon highs. Though rather uncomfortable for early September to see highs in the mid to upper 90s, the heat will not be as severe as our previous episode. Though this will likely be true for Saturday and Sunday, there is some hint that by Monday, dew points will be increasing to the lower 70s and that combined with another day of mid 90s or slightly warmer, could bring us closer to heat indices nearing advisory criteria. Unfortunately, we see no chances for any precipitation through the period which means our dry conditions will likely worsen a bit in the next 5 days. && .AVIATION.../For the 12Z TAFS through 12Z Wednesday morning/ Issued at 606 AM CDT Tue Aug 29 2023 Patchy mid level clouds will move across eastern sites prior to 15z. VFR conditions expected with some mixing aft 15z. Haze from wildfires in Canada may bring 6sm to FOD, MCW, and DSM at times. Confidence on coverage/timing still uncertain, but aft 18z through 00z more likely. Winds decouple around 00z with light north northeast thereafter. && .DMX WATCHES/WARNINGS/ADVISORIES... NONE. && SHORT TERM...REV LONG TERM...REV AVIATION...REV
Hazardous Weather Outlook National Weather Service Des Moines IA 354 AM CDT Tue Aug 29 2023 IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075- 081>086-092>097-300900- 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- 354 AM CDT Tue Aug 29 2023 This Hazardous Weather Outlook is for portions of central Iowa. .DAY ONE...Today and tonight No hazardous weather is expected at this time. .DAYS TWO THROUGH SEVEN...Wednesday through Monday No hazardous weather is expected at this time. .SPOTTER INFORMATION STATEMENT... Spotters will not be needed. REV
The national radar mosaic for the moment the first event began.
9 drought. Local standard time, as filed.
Severe Drought expanded into Hamilton county as hot temperatures and low precipitation persisted late in August.
Severe Drought expanded into Hardin county as hot temperatures and low precipitation persisted late in August.
Severe Drought expanded into Marshall county as hot temperatures and low precipitation persisted late in August.
Severe Drought expanded into Poweshiek county as hot temperatures and low precipitation persisted late in August.
Severe Drought expanded back into Clarke county as hot temperatures and low precipitation persisted late in August.
Severe Drought expanded into Warren county as hot temperatures and low precipitation persisted late in August.
Severe Drought expanded into Carroll county as hot temperatures and low precipitation persisted late in August.
Severe Drought expanded into Audubon county as hot temperatures and low precipitation persisted late in August.
Severe Drought expanded into Guthrie county as hot temperatures and low precipitation persisted late in August.
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, August 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: 1123348, 1123349, 1123350, 1123351, 1123352, 1123353, 1123355, 1123356, 1123357.