An upper level trough was pivoting across the Northern Plains and the Canadian Plains August 17th, with a surface low reflection dragging a cold front through the Dakotas and northern Minnesota.  The aforementioned cold front triggered widespread storms during the afternoon hours of the 17th, slowly propagating eastward. By late evening, a portion of the line of storms formed into an organized linear convective system, with bowing segments, that entered northwest Iowa. Through the overnight hours, the system continued to move across Iowa from northwest to southeast, slowly losing its overall organization and threat for damaging winds. Even though it lost overall strength, with MUCAPE values in excess of 2000 J/kg, precipitable water values in excess of 1.7 inches, and strong low level moisture influx, efficient and heavy rainfall continued as it moved across the state. Many areas received between 2 and 3 inches, with the majority of it falling in around 90 minutes or less.

Heavy Rain in WAYNE, IOWA
From 18-AUG-19 01:35:00 to 18-AUG-19 06:30:00 (CST-6)
Location: HUMESTON
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter, via social media, reported heavy rainfall of 3.43 inches. Beginning and ending times estimated from radar.

Heavy Rain in POLK, IOWA
From 18-AUG-19 02:10:00 to 18-AUG-19 06:15:00 (CST-6)
Location: ANKENY
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

Public reported heavy rainfall of 2.15 inches. Beginning time estimated from radar.

Heavy Rain in POLK, IOWA
From 18-AUG-19 02:05:00 to 18-AUG-19 07:30:00 (CST-6)
Location: GRIMES
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Public reported heavy rainfall of 2.00 inches. Beginning and ending times estimated from radar.

Heavy Rain in LUCAS, IOWA
From 18-AUG-19 01:40:00 to 18-AUG-19 07:00:00 (CST-6)
Location: LUCAS
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Mesonet station recorded heavy rainfall of 2.77 inches. Beginning and ending times estimated from radar.

Heavy Rain in WARREN, IOWA
From 18-AUG-19 02:45:00 to 18-AUG-19 08:00:00 (CST-6)
Location: NORWALK
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Mesonet station recorded heavy rainfall of 2.11 inches. Beginning and ending times estimated from radar.

Heavy Rain in POLK, IOWA
From 18-AUG-19 02:30:00 to 18-AUG-19 07:30:00 (CST-6)
Location: COMMERCE
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

Public reported heavy rainfall of 2.25 inches. Beginning and ending times estimated from radar.

Heavy Rain in WARREN, IOWA
From 18-AUG-19 03:30:00 to 18-AUG-19 08:45:00 (CST-6)
Location: NEW VIRGINIA
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported heavy rainfall of 2.10 inches. Beginning and ending times estimated from radar.

Heavy Rain in CASS, IOWA
From 18-AUG-19 03:40:00 to 18-AUG-19 07:40:00 (CST-6)
Location: ATLANTIC
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Mesonet station recorded heavy rainfall of 2.22 inches. Beginning and ending times estimated from radar.

Heavy Rain in WARREN, IOWA
From 18-AUG-19 02:00:00 to 18-AUG-19 05:00:00 (CST-6)
Location: INDIANOLA
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported heavy rainfall of 2.1 inches roughly between 3am and 6am local time.

Heavy Rain in POLK, IOWA
From 18-AUG-19 02:37:00 to 18-AUG-19 03:07:00 (CST-6)
Location: ALTOONA
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

CoCoRaHS observer reported heavy rainfall of 1.04 inches in 30 minutes.

Heavy Rain in POLK, IOWA
From 18-AUG-19 02:25:00 to 18-AUG-19 07:00:00 (CST-6)
Location: ALTOONA
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported heavy rainfall of 2.52 inches. Beginning and ending times estimated from radar.

Heavy Rain in POWESHIEK, IOWA
From 18-AUG-19 02:55:00 to 18-AUG-19 04:22:00 (CST-6)
Location: MONTEZUMA
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported heavy rainfall of 2.15 inches. Beginning time estimated from radar.

Heavy Rain in JASPER, IOWA
From 18-AUG-19 02:35:00 to 18-AUG-19 05:48:00 (CST-6)
Location: PRAIRIE CITY
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Mesonet station recorded heavy rainfall of 2.49 inches. Beginning time estimated from radar.

Heavy Rain in POLK, IOWA
From 18-AUG-19 02:35:00 to 18-AUG-19 05:54:00 (CST-6)
Location: (DSM)DES MOINES INTL
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Des Moines International Airport ASOS recorded heavy rainfall of 1.97 inches. Beginning time estimated from radar.

Heavy Rain in POLK, IOWA
From 18-AUG-19 02:25:00 to 18-AUG-19 05:59:00 (CST-6)
Location: CAPITOL HGTS
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Mesonet station recorded heavy rainfall of 2.17 inches. Beginning time estimated from radar.

Heavy Rain in CASS, IOWA
From 17-AUG-19 06:00:00 to 18-AUG-19 06:00:00 (CST-6)
Location: ATLANTIC
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Coop observer recorded heavy rainfall of 2.36 inches over the last 24 hours.

Heavy Rain in JASPER, IOWA
From 18-AUG-19 02:35:00 to 18-AUG-19 06:00:00 (CST-6)
Location: VANDALIA
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Mesonet station recorded heavy rainfall of 2.49 inches. Beginning time estimated from radar.

Heavy Rain in POLK, IOWA
From 17-AUG-19 06:00:00 to 18-AUG-19 06:00:00 (CST-6)
Location: ALTOONA
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

CoCoRaHS observer recorded heavy rainfall of 2.05 inches over the last 24 hours.

Heavy Rain in POWESHIEK, IOWA
From 17-AUG-19 06:00:00 to 18-AUG-19 06:00:00 (CST-6)
Location: MONTEZUMA
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Coop observer recorded heavy rainfall of 2.17 inches over the last 24 hours.

Heavy Rain in LUCAS, IOWA
From 18-AUG-19 01:45:00 to 18-AUG-19 06:07:00 (CST-6)
Location: LUCAS
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Mesonet station recorded heavy rainfall of 2.50 inches. Beginning time estimated from radar.

Heavy Rain in WARREN, IOWA
From 18-AUG-19 02:45:00 to 18-AUG-19 06:19:00 (CST-6)
Location: NORWALK
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Mesonet station recorded heavy rainfall of 2.03 inches. Beginning time estimated from radar.

Heavy Rain in CASS, IOWA
From 18-AUG-19 03:40:00 to 18-AUG-19 06:20:00 (CST-6)
Location: ATLANTIC
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Mesonet station recorded heavy rainfall of 2.1 inches. Beginning time estimated from radar.

Heavy Rain in POLK, IOWA
From 18-AUG-19 02:20:00 to 18-AUG-19 06:20:00 (CST-6)
Location: ALTOONA
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

Mesonet station recorded heavy rainfall of 2.07 inches. Beginning time estimated from radar.

Heavy Rain in CASS, IOWA
From 17-AUG-19 06:45:00 to 18-AUG-19 06:45:00 (CST-6)
Location: ANITA MUNI ARPT
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

CoCoRaHS observer recorded heavy rainfall of 2.90 inches over the last 24 hours.

Heavy Rain in DALLAS, IOWA
From 18-AUG-19 02:00:00 to 18-AUG-19 07:17:00 (CST-6)
Location: ADEL
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

Public reported heavy rainfall of 2.6 inches from the home weather station. Beginning time estimated from radar.

Heavy Rain in DALLAS, IOWA
From 18-AUG-19 02:20:00 to 18-AUG-19 07:48:00 (CST-6)
Location: ADEL
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

Public reported heavy rainfall of 2.10 inches. Beginning time estimated from radar.

Heavy Rain in POLK, IOWA
From 18-AUG-19 02:20:00 to 18-AUG-19 07:25:00 (CST-6)
Location: ALTOONA
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

Public reported heavy rainfall of 2.25 inches. Beginning time estimated from radar.