Heavy rain continued into mid October with many rivers going into flood again across much of the forecast area. Flooding was observed in the Des Moines, Iowa, Cedar, Chariton, Thompson and Raccoon River basins.
Every event with a place to put it. 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.
Heavy rain continued into mid October with many rivers going into flood again across much of the forecast area. Flooding was observed in the Des Moines, Iowa, Cedar, Chariton, Thompson and Raccoon River basins.
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 Oct 8, 10:53 PM CST, 3 hours 37 minutes earlier.
Area Forecast Discussion National Weather Service Des Moines IA 1153 PM CDT Mon Oct 8 2018 ...Updated for 06z Aviation Discussion... .SHORT TERM.../Tonight through Tuesday night/ Issued at 338 PM CDT Mon Oct 8 2018 Upper trough over the west that has plagued our weather for the past week or more is finally shifting over the next 36 hours. Model trends have slowed the progression of the upper trough access now until after 18Z Wednesday but the bulk of the precip will still fall by 12Z Wednesday with the eastern portion of the state still under the gun Wednesday morning. As the upper trough slowly lifts, it will push a surface low and frontal boundary from Kansas into Wisconsin by Wednesday morning. This will lift a quasi-stationary frontal boundary northward across Iowa through tonight then a cold front across us Tuesday evening into Wednesday morning. Models develop a couple of weak lows that ride up the boundary and associated with this are enhanced areas of forcing along the boundary. This will cause an overall increase of showers and possibly a few thunderstorms tonight. However CAPE values are best along the boundary but deeper instability is on the weak side. Countering this is some decent unidirectional deep shear of 30- 40kts. The shear and instability combined is enough to see isolated storms and if some better forcing comes up in conjunction with this, storms may become strong enough to produce some damaging wind gusts but coverage would be limited. Tuesday and Tuesday night, better instability pushes into southeast and central Iowa with CAPE values up to 2000 J/Kg. The GFS model is still weak with the NAM very aggressive and advertising the stronger CAPE values. Shear is also stronger Tuesday/Tuesday night with 40- 50kts of deep shear. If we realize the instability...which is still somewhat in doubt, we will see stronger storms Tuesday late day into the evening. Some of these will be severe. Damaging wind and to a lesser extend, large hail would be possible. An isolated tornado along the boundary also couldn't be ruled out. Soundings show PWAT's (precipitable water) values approaching 2 inches which is way above normal for this time of year. Heavy rain and flooding potential is still a threat and flood watches remain in effect for this reason, though just where the heaviest rain will occur is still somewhat in question. Tonight it looks like west central to northeast Iowa then Tuesday/Tuesday night central into eastern Iowa would see the best threat. .LONG TERM.../Wednesday through Monday/ Issued at 338 PM CDT Mon Oct 8 2018 Wednesday afternoon through much of Thursday night will be dry and cool as previously advertised. After 09Z Thursday night, a strong but progressive shortwave will cross the region and kick off the chance for showers mainly across the southern third to half of the state. At this point it does not appear that this will have much impact on rivers or any flood threat. A stronger shortwave will drop through the area Saturday night and Sunday. The main impact from these systems will be to dump shots of very cool air down across Iowa with light precip. The first wave will push highs into the 50s then 40s and 50s for Saturday/Sunday. On Monday a surface high to the south will bring low level return flow to the state and should bump temps up a few degrees but we are still looking at 50s on Monday as well. At least the non-stop periods of rainfall will be ending. As for temps...coldest temps Thursday night into Friday and Friday night into Saturday. Widespread frost is possible over at least the northern half both nights which will likely end the growing season. Lows are forecast to be around freezing to a couple degrees above. && .AVIATION.../For the 06Z TAFS through 06Z Tuesday night/ Issued at 1153 PM CDT Mon Oct 8 2018 Low to perhaps medium confidence forecast with rain/storms and fog/low ceilings impacting the terminals through this TAF period. Worst restrictions down to IFR or LIFR are expected over the northern terminals at FOD and MCW with more MVFR conditions at ALO and DSM. Have left out mention of thunder beyond Tuesday morning to avoid prolonged thunder in TAFs. Strong storms are possible over eastern Iowa Tuesday afternoon and may bring short duration restriction down towards IFR. && .HYDROLOGY... Issued at 338 PM CDT Mon Oct 8 2018 The heaviest rainfall last night fell across southeast Iowa. Tonight showers and storms will move across western and northern Iowa then shift east through the day Tuesday and over the southeast Tuesday night. With the light to moderate rain that Iowa has seen nearly daily for the past week or more, soils are saturated and a potential for 1 to 3 additional inches of rain has set the stage for potential flooding. The flood watch will continue. No changes were made to the areal outline of this for now but if more rain falls over the southeast, that may need to be included. As of this afternoon, WPC places the heaviest rainfall and the moderate flood risk mainly central and west. && .DMX WATCHES/WARNINGS/ADVISORIES... Flood Watch through Wednesday morning for IAZ004>007-015>017- 023>028-033>039-044>050-057>062-070>075-081>084-092>094. && SHORT TERM...FAB LONG TERM...FAB AVIATION...Ansorge HYDROLOGY...FAB
Hazardous Weather Outlook National Weather Service Des Moines IA 421 AM CDT Mon Oct 8 2018 IAZ004>007-015>017-023>028-033>039-044>050-057>062-070>075- 081>084-092>094-090930- 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-Taylor-Ringgold-Decatur- 421 AM CDT Mon Oct 8 2018 This Hazardous Weather Outlook is for portions of central Iowa. .DAY ONE...Today and tonight Areas of heavy rainfall are possible today and tonight. Reference the Flood Watch for additional details. In additional, isolated severe storms are possible this afternoon and evening. Damaging wind gusts are the primary threat. A Flood Watch is in effect for the area in addition to other localized River Flood Watches. Please refer to the National Weather Service website at weather.gov/desmoines for further details. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday Heavy rainfall will remain possible through Tuesday night. A slight risk for severe weather is forecast for Tuesday afternoon and evening. Damaging wind gusts are the primary threat. A Flood Watch remains in effect for the area through Tuesday night in addition to other localized River Flood Watches. Please refer to the National Weather Service website at weather.gov/desmoines for further details. .SPOTTER INFORMATION STATEMENT... Spotters may be needed for flooding and heavy rain reports through Tuesday night. IAZ085-086-095>097-090930- Monroe-Wapello-Wayne-Appanoose-Davis- 421 AM CDT Mon Oct 8 2018 This Hazardous Weather Outlook is for portions of central Iowa. .DAY ONE...Today and tonight Showers and thunderstorms are possible today and tonight. Locally heavy rainfall and and isolated severe storm are possible. .DAYS TWO THROUGH SEVEN...Tuesday through Sunday Periodic showers and a few thunderstorms are forecast through early Wednesday. The primary threat is locally heavy rainfall which may lead to overland flooding, ponding water and even localized flash flooding. There is a Slight Risk of severe storms Tuesday afternoon and evening with the primary threat being damaging wind gusts. .SPOTTER INFORMATION STATEMENT... Spotters may be needed for flooding and heavy rain reports and possible severe weather late Tuesday.
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE DES MOINES IA
1048 PM CDT MON OCT 8 2018
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1030 PM HEAVY RAIN UDELL 40.78N 92.74W
10/08/2018 E2.00 INCH APPANOOSE IA TRAINED SPOTTER
RAIN 0700-2230.
&&
AKThe national radar mosaic for the moment the first event began.
11 flood. Local standard time, as filed.
The Thompson River at Davis City crested at 13.07 ft on 9 October 2018 at 13:00 UTC.
The Iowa River at Marshalltown crested twice, the first crest was at 15.05 ft on 10 October 2018 at 08:15 UTC, the second was at 15.28 ft on 11 October 2018 at 10:00 UTC.
The Raccoon River at Des Moines at Fleur Drive crested twice, the first crest at 15.13 ft on 11 October 2018 at 02:30 UTC, the second crest at 15.06 ft on 13 October 2018 at 09:45 UTC.
The Chariton River at Chariton crested at 19.82 ft on 9 October 2018 at 01:15 UTC.
The Cedar River at Cedar Falls crested at 92.63 ft on 13 October 2018 at 00:30 UTC.
The Cedar River at Waterloo crested at 15.09 ft on 12 October 2018 at 21:45 UTC.
The Iowa River at Tama Highway E49 crested at 13.23 ft on 12 October 2018 at 19:15 UTC.
The Des Moines River at Fort Dodge crested at 10.81 ft on 11 October 2018 at 09:15 UTC.
The North Raccoon River at Perry crested at 17.86 ft on 12 October 2018 at 05:45 UTC.
The West Fork of the Des Moines River at Estherville crested at 8.92 ft on 12 October 2018 at 23:45 UTC.
The West Fork of the Des Moines River at Humboldt crested at 10.11 ft on 12 October 2018 at 17:00 UTC.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Iowa in 2018Every state in 2018This day in weather historyWarnings in Iowa, October 2018
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: 789592, 789580, 789591, 789593, 789596, 789595, 789576, 789587, 789577, 789589, 789584.