Southern Iowa found itself north of a relatively stationary surface boundary, which was laid out across northern Missouri. An 850mb front was situated a bit further north, over much of southern Iowa, with a decent moisture fetch from the Gulf of Mexico.
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.
Southern Iowa found itself north of a relatively stationary surface boundary, which was laid out across northern Missouri. An 850mb front was situated a bit further north, over much of southern Iowa, with a decent moisture fetch from the Gulf of Mexico. Given the relation to the surface front, elevated showers and storms were the name of the game. MUCAPE values were generally around 1000 to 1500 J/kg, along with precipitable water values approaching 1.5 to 1.75 inches, climatologically anomalous for the time of the year. Lacking supporting parameters, no severe weather was seen, but heavy rainfall did lead to localized flooding. As thunderstorms moved through the Des Moines metro area, three individuals were struck by lightning walking to their cars in a parking lot.
The national radar mosaic for the moment the first event began.
5 heavy rain, 2 flood, 1 lightning. Local standard time, as filed.
Coop observer recorded heavy rainfall of 2.69 inches over the last 24 hours.
Coop observer recorded heavy rainfall of 2.51 inches over the last 24 hours.
Public reported heavy rainfall of 2.40 inches. Beginning time estimated from radar.
Public reported heavy rainfall of 3 inches. Beginning and ending times estimated from radar.
Trained spotter reported heavy rainfall of 3.08 inches. Beginning time estimated from radar.
Reported by an off duty NWS employee. Three individuals were struck by lightning walking to their cars in the parking lot. Minor injuries reported.
Iowa DOT reported water covering Highway 92 between Highway T17 and Highway 163 in Mahaska County.
Iowa DOT reported water covering Highway 92 between Highway T17 in Marion County and Highway 163 in near Oskaloosa.
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: 787218, 787219, 787222, 787221, 787220, 789920, 787217, 789911.