A continuation of above normal temperatures and lack of rainfall contributed to a deterioration of drought conditions in additional portions of central Iowa with Severe Drought contitions widening. This was an expansion of a much larger area of severe or worse drought conditions over a large portions of Iowa.
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 DMX wrote it up.
A continuation of above normal temperatures and lack of rainfall contributed to a deterioration of drought conditions in additional portions of central Iowa with Severe Drought contitions widening. This was an expansion of a much larger area of severe or worse drought conditions over a large portions of 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 12, 5:30 AM CST, 1 hour 30 minutes earlier.
Area Forecast Discussion National Weather Service Des Moines IA 630 AM CDT Tue Sep 12 2023 ...Updated for the 12z Aviation Discussion... .DISCUSSION.../Today through Monday/ Issued at 312 AM CDT Tue Sep 12 2023 Key Messages: -Dense fog in the southeast this morning, a few light showers north today. -Tranquil and seasonal Wednesday into Thursday. -Threat of scattered showers and isolated thunder return late Friday into Saturday. Dense fog has developed in southeast portions of the forecast area where high dewpoints reside over locations which saw decent rainfall last night. The clear skies and light winds are promoting development and it is expected the fog will linger through mid morning before burning off after sunrise and a Dense Fog Advisory has been issued for this area. Otherwise, a shortwave was dropping southeast through the upper Midwest on the backside of a Great Lakes upper trof. A few light showers/sprinkles were occurring this morning in an area of stronger mid level kinematic forcing in southern Minnesota. Moisture is quite limited, therefore the rainfall is scattered and light. However, as the lift drops into the state today along with a weak surface trof, some light pcpn is expected during the day in northern Iowa. Any threat of rainfall ends quickly into tonight with increasing subsidence on the backside of the departing shortwave. Otherwise, another cool night is likely across the state with light winds once again. Weak upper ridging slides into the central United States by Wednesday and lingers into Thursday with quiet weather over Iowa and surrounding areas. Temperatures are likely to remain mostly seasonal during this time with main thermal ridging remaining west of the state. Much of Friday also appears to remain relatively quiet however a front approaches northwest Iowa by late in the day as an upper low drops into the northern Midwest. Models are suggesting some threat of showers/isolated storms late Friday into Friday night moving from west to east across the state in vicinity of the advancing front. Lingering spotty showers remain across portions of central and eastern Iowa on Saturday with cool mid level temperatures promoting development, especially by afternoon with daytime heating. Otherwise, the remainder of the weekend looks quiet with cooler temperatures into Sunday. Warm advection returns by next Monday ahead of a rapidly advancing front but the lack of significant moisture in the area is likley to limit any precipitation with this front late Monday/early Tuesday to mostly isolated in coverage. && .AVIATION.../For the 12Z TAFS through 12Z Wednesday morning/ Issued at 630 AM CDT Tue Sep 12 2023 MVFR to IFR fog will dissipate quickly this morning across southeast Iowa. Otherwise, VFR ceilings are expected in portions of northern spreading into central Iowa today with some sprinkles and scattered light showers. Winds remain light from the north to northwest today becoming light and variable tonight. && .DMX WATCHES/WARNINGS/ADVISORIES... Dense Fog Advisory until 9 AM CDT this morning for IAZ074-075- 084>086-095>097. && DISCUSSION...Cogil AVIATION...Cogil
Hazardous Weather Outlook National Weather Service Des Moines IA 331 AM CDT Tue Sep 12 2023 IAZ004-005-015-023-024-033>036-044>048-057>062-070>075-081>086- 092>097-130845- Emmet-Kossuth-Palo Alto-Pocahontas-Humboldt-Sac-Calhoun-Webster- Hamilton-Crawford-Carroll-Greene-Boone-Story-Audubon-Guthrie- Dallas-Polk-Jasper-Poweshiek-Cass-Adair-Madison-Warren-Marion- Mahaska-Adams-Union-Clarke-Lucas-Monroe-Wapello-Taylor-Ringgold- Decatur-Wayne-Appanoose-Davis- 331 AM CDT Tue Sep 12 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 Scattered thunderstorms will be possible again late Friday into Saturday, mainly over western Iowa. Severe potential remains low. .SPOTTER INFORMATION STATEMENT... Spotter activation will not be needed. IAZ006-007-016-017-025>028-037>039-049-050-130845- Winnebago-Worth-Hancock-Cerro Gordo-Wright-Franklin-Butler-Bremer- Hardin-Grundy-Black Hawk-Marshall-Tama- 331 AM CDT Tue Sep 12 2023 This Hazardous Weather Outlook is for portions of central Iowa. .DAY ONE...Today and tonight A few brief, isolated thunderstorms are possible this afternoon, but severe weather is not anticipated. .DAYS TWO THROUGH SEVEN...Wednesday through Monday Scattered thunderstorms will be possible again late Friday into Saturday, mainly over western Iowa. Severe potential remains low. .SPOTTER INFORMATION STATEMENT... Spotter activation will not be needed. Dodson
The national radar mosaic for the moment the first event began.
11 drought. Local standard time, as filed.
Above normal temperatures and lack of precipitation allowed severe drought conditions to expand into portions of Greene county during the later half of September.
Above normal temperatures and lack of precipitation allowed severe drought conditions to expand into portions of Boone county during the later half of September.
Above normal temperatures and lack of precipitation allowed severe drought conditions to expand into portions of Story county during the later half of September.
Above normal temperatures and lack of precipitation allowed severe drought conditions to expand into portions of Cass county during the later half of September.
Above normal temperatures and lack of precipitation allowed severe drought conditions to expand into portions of Adair county during the later half of September.
Above normal temperatures and lack of precipitation allowed severe drought conditions to expand into portions of Madison county during the later half of September.
Above normal temperatures and lack of precipitation allowed severe drought conditions to expand into portions of Adams county during the later half of September.
Above normal temperatures and lack of precipitation allowed severe drought conditions to expand into portions of Union county during the later half of September.
Above normal temperatures and lack of precipitation allowed severe drought conditions to expand into portions of Ringgold county during the later half of September.
Above normal temperatures and lack of precipitation allowed severe drought conditions to expand into portions of Decatur county during the later half of September.
Above normal temperatures and lack of precipitation allowed severe drought conditions to expand into portions of Palo Alto county during the later half of September.
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: 1139696, 1139697, 1139698, 1139699, 1139700, 1139701, 1139702, 1139703, 1139704, 1139705, 1139706.