Severe drought conditions were alleviated by generous widespread rainfall late in October.
Every event with a place to put it; 3 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.
Severe drought conditions were alleviated by generous widespread rainfall late in October.
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 30, 10:47 PM CST, 1 hour 13 minutes earlier.
Area Forecast Discussion National Weather Service Des Moines IA 1147 PM CDT Thu Sep 30 2021 ...Updated for the 06z Aviation Discussion... .DISCUSSION.../Tonight through Thursday/ Issued at 343 PM CDT Thu Sep 30 2021 Key Message: -Scattered shower/thunderstorm threat to persist into the weekend. -Cooler and dry into early next week. Overnight and morning thunderstorms produced generous rainfall in portions of western and central Iowa. Audubon cooperative observer came in with 3.17" and another public report of 3.70" near Audubon as well. This activity has exited into Minnesota this afternoon with partly sunny skies in many locations. This has pushed temperatures well into the 70s and 80s across the area along with CAPE value of ~3000 J/KG in western Iowa. Scattered convection has recently expanded in central Iowa where little capping exists but overall organization is low. This is a result of paltry shear across the area with top winds of 22kts in the entire forecast sounding above KDSM this afternoon. Therefore, severe weather threat this afternoon into tonight appears quite muted unless a developing storm can produce a sufficient updraft for some hail development before collapsing. In addition, in far western portions of the forecast area, low level (0-3KM) CAPE values of 125 overlie some low level vorticity. There is some outside threat of a funnel cloud or two with developing cells as well but should be limited to late this afternoon/early evening. Otherwise, the scattered convection persist overnight mainly along and west of the I35 corridor as a weak surface wave passes north through the Missouri River Valley in western Iowa. PWAT values of 1.50-1.75" and relatively deep warm cloud layer should lead to efficient rain production and locally heavy rainfall also remains possible. A break in activity is once again expected by Friday morning into early afternoon prior to additional development as daytime heating progresses. Forcing pushes farther east with this activity with expansion into eastern portions of the forecast area by afternoon into early evening hours. Coverage is likely to remain scattered and with lax shear, the severe weather threat remains limited. This activity continues into Friday night before increasing subsidence ends precipitation by Saturday morning. Models continue to indicate forcing increasing once again later Saturday into Saturday night across mainly southern Iowa with GFS remaining farther north than the Euro. Showers and a few embedded storm are expected across southern Iowa up to the I80 corridor or so. This activity persist into Sunday morning before ending. Thereafter, an upper low cut off southeast of Iowa with the state in generally cool and dry northeast flow. This is likely to produce near seasonal temperatures into early next week along with little chance for precipitation. && .AVIATION.../For the 06Z TAFS through 06Z Friday night/ Issued at 1137 PM CDT Thu Sep 30 2021 Scattered TSRA has largely wound down across the area, with SHRA lingering at KFOD for another hour or so. A break in conditions should yield predominantly VFR conditions through around 18z before additional scattered storm/VCTS activity overspreads and moves across all TAF sites. Prevailing MVFR/IFR ceilings expected to develop overnight west of the area should mostly remain out of TAF sites, but may encroach KFOD/KDSM and need to be monitored. && .DMX WATCHES/WARNINGS/ADVISORIES... NONE. && DISCUSSION...Cogil AVIATION...Curtis
Hazardous Weather Outlook National Weather Service Des Moines IA 308 PM CDT Thu Sep 30 2021 IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075- 081>086-092>097-012015- 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- 308 PM CDT Thu Sep 30 2021 This Hazardous Weather Outlook is for portions of central Iowa. .DAY ONE...This afternoon and tonight There will be chances for thunderstorms into tonight, but the severe weather potential is low. Locally heavy rainfall is possible at times. .DAYS TWO THROUGH SEVEN...Friday through Wednesday Chances for thunderstorms will remain in the forecast through Sunday. Severe weather is not expected. .SPOTTER INFORMATION STATEMENT... Spotter activation is unlikely. Bury/Cogil
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
1255 AM CDT FRI OCT 1 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
0900 AM HEAVY RAIN 1 NE AUDUBON 41.72N 94.92W
09/30/2021 M3.70 INCH AUDUBON IA TRAINED SPOTTER
REPORT FROM FRIDAY MORNING.
&&
BSSThe national radar mosaic for the moment the first event began.
3 drought. Local standard time, as filed.
Portions of Carroll county had severe drought conditions through much of October. These conditions improved with generous rainfall late in the month.
Portions of Greene county had severe drought conditions through much of October. These conditions improved with generous rainfall late in the month.
Portions of Webster county had severe drought conditions through much of October. These conditions improved with generous rainfall late in the month.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Iowa in 2021Every state in 2021This day in weather historyWarnings in Iowa, October 2021
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: 989485, 989486, 989487.