A surface low pressure system that moved across South Dakota and Minnesota, dragging behind it a cold front that moved into portions of northwest and central Iowa on the 30th of September. As the surface front moved through Iowa, it stalled out and effectively divided the state in half as it oriented it self from southwest to northeast across the state. While the itself stalled, it separated two distinctly different air masses with temperatures in the 50s to low 70s prevailing on the north side and 80s to around 90 prevailing to the south. Surface moisture was also divided with dew points in the 50s on the cool side and low to mid 70s on the warm side.
Showers and storms persisted north of the front overnight of the 30th into the 1st and during much of the day of the 1st. That activity yielded little more than periods of moderate to heavy rain and sub-severe thunderstorms. Along and south of the front, thermodynamic and kinematics yielded much more vigorous storms and ultimately heavy rainfall and severe weather. SBCAPE profiles yielded 2000 to 3000+ J/kg by early to mid afternoon along with effective bulk shear around 50 to 60 kts, and persistent strong moisture flow yielding precipitable water values around 1.75 to 2.0 inches. Additionally, in the lowest 1 to 3 km, CAPE values exceed 100 J/kg and was accompanied by enhanced low level helicity due to frontal proximity. As a result, virtually all modes of severe weather were possible. In the end, the majority of reports revolved around severe hail, nearing 3 inches in diameter, and heavy rainfall in excess of 3 to 4 inches. A handful of funnel cloud and damaging wind reports were also received.

Heavy Rain in WARREN, IOWA
From 01-OCT-19 06:00:00 to 02-OCT-19 06:00:00 (CST-6)
Location: SPRING HILL
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

CoCoRaHS observer recorded heavy rainfall of 3.49 inches over the past 24 hours.

Heavy Rain in POLK, IOWA
From 01-OCT-19 06:00:00 to 02-OCT-19 06:00:00 (CST-6)
Location: DES MOINES
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

CoCoRaHS observer recorded heavy rainfall of 2.58 inches over the past 24 hours.

Heavy Rain in DALLAS, IOWA
From 01-OCT-19 04:00:00 to 02-OCT-19 04:00:00 (CST-6)
Location: HADDEN HILL
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

CoCoRaHS observer recorded heavy rainfall of 2.17 inches over the past 24 hours.

Heavy Rain in POWESHIEK, IOWA
From 01-OCT-19 07:35:00 to 02-OCT-19 07:35:00 (CST-6)
Location: GRINNELL ARPT
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Grinnell Municipal Airport AWOS recorded heavy rainfall of 3.19 inches over the last 24 hours.

Heavy Rain in JASPER, IOWA
From 01-OCT-19 07:35:00 to 02-OCT-19 07:35:00 (CST-6)
Location: NEWTON MUNI ARPT
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Newton Municipal Airport AWOS recorded heavy rainfall of 3.35 inches over the last 24 hours.

Heavy Rain in POWESHIEK, IOWA
From 01-OCT-19 05:00:00 to 02-OCT-19 05:00:00 (CST-6)
Location: GRINNELL
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Social Media

Public reported heavy rainfall of 5.78 inches over the past 24 hours.

Heavy Rain in JASPER, IOWA
From 01-OCT-19 15:30:00 to 01-OCT-19 23:45:00 (CST-6)
Location: NEWTON
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported storm total heavy rainfall of 5.16 inches. Beginning and ending times estimated from radar.

Heavy Rain in JASPER, IOWA
From 01-OCT-19 16:00:00 to 01-OCT-19 18:46:00 (CST-6)
Location: NEWTON
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Public reported heavy rainfall of 3.06 inches so far. Beginning time estimated from radar.

Heavy Rain in WEBSTER, IOWA
From 01-OCT-19 05:00:00 to 02-OCT-19 05:00:00 (CST-6)
Location: FT DODGE
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

CoCoRaHS observer recorded heavy rainfall of 2.10 inches over the past 24 hours.

Heavy Rain in BUTLER, IOWA
From 01-OCT-19 12:09:00 to 02-OCT-19 12:09:00 (CST-6)
Location: NEW HARTFORD
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported heavy rainfall of 2.47 inches since yesterday.

Heavy Rain in DALLAS, IOWA
From 01-OCT-19 15:30:00 to 01-OCT-19 23:30:00 (CST-6)
Location: HADDEN HILL
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Employee

Retired NWS employee reported heavy rainfall of 2.70 inches. Beginning and ending times estimated from radar.

Heavy Rain in JASPER, IOWA
From 01-OCT-19 16:00:00 to 01-OCT-19 21:11:00 (CST-6)
Location: NEWTON
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported heavy rainfall of 3.91 inches so far. Beginning time estimated from radar.

Hail in BLACK HAWK, IOWA
From 01-OCT-19 16:54:00 to 01-OCT-19 16:54:00 (CST-6)
Location: CEDAR FALLS ARPT
Magnitude: 0.75 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported nickel sized hail.

Heavy Rain in KOSSUTH, IOWA
From 01-OCT-19 05:40:00 to 02-OCT-19 05:40:00 (CST-6)
Location: ALGONA
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

CoCoRaHS observer recorded heavy rainfall of 2.09 inches over the past 24 hours.

Heavy Rain in WARREN, IOWA
From 01-OCT-19 06:00:00 to 02-OCT-19 06:00:00 (CST-6)
Location: NORWALK
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

CoCoRaHS observer recorded heavy rainfall of 3.40 inches over the past 24 hours.

Heavy Rain in POLK, IOWA
From 01-OCT-19 15:30:00 to 01-OCT-19 23:30:00 (CST-6)
Location: URBANDALE
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Public reported storm total heavy rainfall of 2.5 inches. Beginning and ending times estimated from radar.

Heavy Rain in TAMA, IOWA
From 01-OCT-19 06:00:00 to 02-OCT-19 06:00:00 (CST-6)
Location: VINING
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

CoCoRaHS observer recorded heavy rainfall of 2.15 inches over the past 24 hours.

Heavy Rain in POLK, IOWA
From 01-OCT-19 06:00:00 to 02-OCT-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 2.23 inches over the past 24 hours.

Heavy Rain in POLK, IOWA
From 01-OCT-19 06:00:00 to 02-OCT-19 06:00:00 (CST-6)
Location: SAYDELL
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

CoCoRaHS observer recorded heavy rainfall of 2.44 inches over the past 24 hours.

Heavy Rain in POLK, IOWA
From 01-OCT-19 06:00:00 to 02-OCT-19 06:00:00 (CST-6)
Location: URBANDALE
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

CoCoRaHS observer recorded heavy rainfall of 2.32 inches over the past 24 hours.

Heavy Rain in POLK, IOWA
From 01-OCT-19 06:00:00 to 02-OCT-19 06:00:00 (CST-6)
Location: WINDSOR HGTS
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

CoCoRaHS observer recorded heavy rainfall of 2.22 inches over the past 24 hours.

Heavy Rain in POLK, IOWA
From 01-OCT-19 06:00:00 to 02-OCT-19 06:00:00 (CST-6)
Location: SAYLORVILLE
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

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

Heavy Rain in POLK, IOWA
From 01-OCT-19 06:00:00 to 02-OCT-19 06:00:00 (CST-6)
Location: URBANDALE
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

CoCoRaHS observer recorded heavy rainfall of 2.22 inches over the past 24 hours.

Heavy Rain in POLK, IOWA
From 01-OCT-19 06:00:00 to 02-OCT-19 06:00:00 (CST-6)
Location: BONDURANT
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

CoCoRaHS observer recorded heavy rainfall of 2.14 inches over the past 24 hours.

Hail in ADAIR, IOWA
From 01-OCT-19 15:05:00 to 01-OCT-19 15:05:00 (CST-6)
Location: ORIENT
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Public reported dime to quarter sized hail and small branches broken in the street.

Heavy Rain in POWESHIEK, IOWA
From 01-OCT-19 06:20:00 to 02-OCT-19 06:20:00 (CST-6)
Location: GRINNELL
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

CoCoRaHS observer recorded heavy rainfall of 4.25 inches over the past 24 hours.

Funnel Cloud in JASPER, IOWA
From 01-OCT-19 17:05:00 to 01-OCT-19 17:05:00 (CST-6)
Location: METZ
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Emergency manager reported a funnel cloud.

Hail in POLK, IOWA
From 01-OCT-19 16:34:00 to 01-OCT-19 16:34:00 (CST-6)
Location: DES MOINES
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Amateur Radio

Amateur radio operator reported quarter sized hail.

Heavy Rain in BOONE, IOWA
From 01-OCT-19 07:00:00 to 02-OCT-19 07:00:00 (CST-6)
Location: OGDEN
Property damage: 0.00K
Crop damage: 0.00K
Reported by: COOP Observer

Coop observer recorded heavy rainfall of 2.70 inches over the past 24 hours.

Heavy Rain in BUTLER, IOWA
From 01-OCT-19 07:00:00 to 02-OCT-19 07:00:00 (CST-6)
Location: KESLEY
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported heavy rainfall of 2.76 in their rain gauge this morning. This is a 24 hour report.

Hail in POLK, IOWA
From 01-OCT-19 16:32:00 to 01-OCT-19 16:32:00 (CST-6)
Location: DES MOINES
Magnitude: 1.00 
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Public

Public reported quarter sized hail via mPING app.

Heavy Rain in CERRO GORDO, IOWA
From 01-OCT-19 06:00:00 to 02-OCT-19 06:00:00 (CST-6)
Location: SWALEDALE
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

CoCoRaHS observer recorded heavy rainfall of 2.31 inches over the past 24 hours.

Heavy Rain in DALLAS, IOWA
From 01-OCT-19 07:00:00 to 02-OCT-19 07:00:00 (CST-6)
Location: REDFIELD
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

CoCoRaHS observer recorded heavy rainfall of 2.12 inches over the past 24 hours.

Heavy Rain in POLK, IOWA
From 01-OCT-19 06:54:00 to 02-OCT-19 06:54:00 (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 2.74 inches over the last 24 hours.

Heavy Rain in POLK, IOWA
From 01-OCT-19 07:00:00 to 02-OCT-19 07:00:00 (CST-6)
Location: WEST DES MOINES
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

CoCoRaHS observer recorded heavy rainfall of 3.28 inches over the past 24 hours.

Heavy Rain in BOONE, IOWA
From 01-OCT-19 06:00:00 to 02-OCT-19 06:00:00 (CST-6)
Location: MOINGONA
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

CoCoRaHS observer recorded heavy rainfall of 2.02 inches over the past 24 hours.

Heavy Rain in POLK, IOWA
From 01-OCT-19 07:00:00 to 02-OCT-19 07:00:00 (CST-6)
Location: CLOVER HILLS
Property damage: 0.00K
Crop damage: 0.00K
Reported by: NWS Employee

NWS employee recorded heavy rainfall of 2.48 inches in their rain gage this morning. This is a 24 hour report.

Funnel Cloud in MADISON, IOWA
From 01-OCT-19 15:55:00 to 01-OCT-19 15:55:00 (CST-6)
Location: WINTERSET ARPT
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported funnel clouds, noting that they were not near the ground.

Heavy Rain in CERRO GORDO, IOWA
From 01-OCT-19 06:00:00 to 02-OCT-19 06:00:00 (CST-6)
Location: CLEAR LAKE JCT
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

CoCoRaHS observer recorded heavy rainfall of 2.63 inches over the past 24 hours.

Heavy Rain in BLACK HAWK, IOWA
From 01-OCT-19 06:30:00 to 02-OCT-19 06:30:00 (CST-6)
Location: WATERLOO
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

CoCoRaHS observer recorded heavy rainfall of 2.44 inches over the past 24 hours.

Hail in POLK, IOWA
From 01-OCT-19 16:32:00 to 01-OCT-19 16:32:00 (CST-6)
Location: DES MOINES
Magnitude: 2.75 
Property damage: 250.00K
Crop damage: 0.00K
Reported by: Social Media

Public reported baseball sized hail via picture from social media.

Heavy Rain in DALLAS, IOWA
From 01-OCT-19 07:35:00 to 02-OCT-19 07:35:00 (CST-6)
Location: PERRY MUNI ARPT
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Perry Municipal Airport AWOS recorded heavy rainfall of 2.07 inches over the last 24 hours.

Hail in MADISON, IOWA
From 01-OCT-19 15:33:00 to 01-OCT-19 15:33:00 (CST-6)
Location: MIDDLE RIVER
Magnitude: 1.50 
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Emergency manager reported ping pong ball sized hail at Highway 92 and Pitzer Road.

Hail in POLK, IOWA
From 01-OCT-19 16:32:00 to 01-OCT-19 16:32:00 (CST-6)
Location: FT DES MOINES
Magnitude: 1.50 
Property damage: 50.00K
Crop damage: 0.00K
Reported by: Social Media

Public relayed video depicting ping pong ball sized hail.

Hail in POLK, IOWA
From 01-OCT-19 16:27:00 to 01-OCT-19 16:27:00 (CST-6)
Location: (DSM)DES MOINES INTL
Magnitude: 1.75 
Property damage: 10.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Broadcast media relayed golf ball sized hail report.

Hail in POLK, IOWA
From 01-OCT-19 16:31:00 to 01-OCT-19 16:31:00 (CST-6)
Location: DES MOINES
Magnitude: 1.25 
Property damage: 5.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported half dollar sized hail.

Thunderstorm Wind in TAYLOR, IOWA
From 01-OCT-19 17:45:00 to 01-OCT-19 17:45:00 (CST-6)
Location: BEDFORD ARPT
Magnitude: 61.00 EG
Property damage: 25.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported 3 or 4 large trees uprooted, including one that fell on the spotter's house. They also noted several other tree limbs down throughout the neighborhood. Time estimated from radar.

Hail in POLK, IOWA
From 01-OCT-19 16:30:00 to 01-OCT-19 16:30:00 (CST-6)
Location: (DSM)DES MOINES INTL
Magnitude: 2.50 
Property damage: 100.00K
Crop damage: 0.00K
Reported by: Broadcast Media

WHO TV relayed tennis ball sized hail report. Time estimated from radar.

Hail in ADAIR, IOWA
From 01-OCT-19 15:12:00 to 01-OCT-19 15:12:00 (CST-6)
Location: ZION
Magnitude: 1.75 
Property damage: 2.00K
Crop damage: 0.00K
Reported by: Trained Spotter

Trained spotter reported golf ball sized hail.