During the evening of Sunday, June 28th, a complex of thunderstorms that developed across Iowa previously, moved slowly northward across southern Minnesota before stalling in central Minnesota Monday morning. Before the torrential rain began in south central Minnesota, a few of the storms caused minor damage to a home in Sibley County.
Deep moisture convergence along the axis of thunderstorms, training along the periphery of the the numerous boundaries, combined with PWAT values of 1.7 to 1.9 inches which is over the 99th percentile value, caused extreme rainfall rates.
There were two specific areas that the storms trained for a few hours and caused rainfall amounts of 4 of 8 inches. The first started around midnight just north of the Minnesota River Valley from Olivia, east-southeast to Winthrop, and Gaylord. Based on the return period from precipitation amounts in a specific time frame, the values were a 100-200 year event. Flash flood guidance values were 2 to 3 times above normal. As this area began to diminish, another area formed southeast of this area. The main area that received rainfall rates as high as 2 inches per hour occurred from southwest of New Ulm, northeast to St. Peter, and south of Montgomery. Other areas also received very heavy rainfall amounts in the south and southeast part of the Twin Cities metro area where locally 3 to 6 inches fell, with the heavier amounts of 6.04 inches over Afton, 5.55 inches near Burnsville, and 5.43 inches over Cottage Grove.
As the runoff continued through the morning, the flash flood event become more areal flooding as the flood waters receded into creeks, streams, and eventually the mainstem rivers.
Some of the highest rainfall totals around the area are as follows.
7 miles south of Bird Island, 7.56 inches.
5 miles north of Lake Crystal, 7.45 inches.
3 miles southwest of Kasota, 6.74 inches.
4 miles north of Miesville, 6.37 inches.

Heavy Rain in DAKOTA, MINNESOTA
From 28-JUN-20 18:00:00 to 29-JUN-20 06:00:00 (CST-6)
Location: LAKEVILLE
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

There was a 12 hour rainfall report near Lakeville of 5.40 inches.

Flash Flood in BLUE EARTH, MINNESOTA
From 29-JUN-20 07:30:00 to 29-JUN-20 11:30:00 (CST-6)
Location: CAMBRIA
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: State Official

Several roads were underwater across northwest Blue Earth County, including 206th, 105th, and 494th. A mudslide occurred at Highway 68 and County Road 42 at Judson, it was the result of the water flowing out of a drainage ditch/creek, 1/2 mile south on 42 that overflowed its banks where it turns and crosses County Road 42. It rushed through corn and hay fields carrying mud, parts of trees and deep fast moving water. On the west side it knocked flat a swath of shoulder high corn to pool along 68 and 42 because the culvert under hwy 68 couldn't handle the flow. There were other roads across northern and western parts of Blue Earth County, but the flooding was not as severe.

Heavy Rain in GOODHUE, MINNESOTA
From 28-JUN-20 18:00:00 to 29-JUN-20 06:00:00 (CST-6)
Location: CANNON FALLS
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

There was a 12 hour rainfall report near Cannon Falls of 5.28 inches.

Thunderstorm Wind in SIBLEY, MINNESOTA
From 28-JUN-20 23:25:00 to 28-JUN-20 23:25:00 (CST-6)
Location: GIBBON
Magnitude: 52.00 EG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Trained Spotter

A trained spotter noted that a few trees were blown down around her farm.

Flash Flood in SIBLEY, MINNESOTA
From 29-JUN-20 01:30:00 to 29-JUN-20 03:30:00 (CST-6)
Location: GAYLORD
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

Several local officials and trained spotters indicated the excessive rainfall caused numerous roads to flood between Gibbon, Winthrop, and Gaylord. Flood waters came out of the middle branch of the Rush River, and over the golf course in Winthrop. Even as the flood waters receded several roads were closed or partially reopened.

Heavy Rain in DAKOTA, MINNESOTA
From 28-JUN-20 18:00:00 to 29-JUN-20 06:00:00 (CST-6)
Location: MIESVILLE
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

There was a 12 hour rainfall report northeast of Miesville of 6.37 inches.

Heavy Rain in BLUE EARTH, MINNESOTA
From 28-JUN-20 18:00:00 to 29-JUN-20 06:00:00 (CST-6)
Location: JUDSON
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

There was a 12 hour rainfall report near Judson of 5.50 inches.

Heavy Rain in DAKOTA, MINNESOTA
From 28-JUN-20 18:00:00 to 29-JUN-20 06:00:00 (CST-6)
Location: LAKEVILLE
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

There was a 12 hour rainfall report near Burnsville of 5.55 inches.

Flash Flood in NICOLLET, MINNESOTA
From 29-JUN-20 07:30:00 to 29-JUN-20 10:30:00 (CST-6)
Location: NICOLLET
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Law Enforcement

There were numerous reports of flooded or closed roadways due to water over the road across southern Nicollet County. There were multiple mud slides in the Minnesota River Valley, including one on Highway 169, south of St. Peter. There was also rushing water over 490th street at Highway 14, southeast of Nicollet.

Heavy Rain in DAKOTA, MINNESOTA
From 28-JUN-20 18:00:00 to 29-JUN-20 06:00:00 (CST-6)
Location: MIESVILLE
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

There was a 12 hour rainfall report near Miesville of 5.86 inches.

Flood in RICE, MINNESOTA
From 29-JUN-20 07:00:00 to 29-JUN-20 10:00:00 (CST-6)
Location: SHIELDSVILLE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: State Official

Local officials closed Shieldville Road between Shields and Mazaska Lake due to high water from flood waters.

Heavy Rain in GOODHUE, MINNESOTA
From 28-JUN-20 18:00:00 to 29-JUN-20 06:00:00 (CST-6)
Location: CANNON FALLS
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

There was a 12 hour rainfall report south of Cannon Falls of 5.54 inches.

Heavy Rain in LE SUEUR, MINNESOTA
From 28-JUN-20 18:00:00 to 29-JUN-20 12:00:00 (CST-6)
Location: KASOTA
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

There was a 18 hour rainfall report near Kasota of 5.94 inches.

Flood in RICE, MINNESOTA
From 29-JUN-20 07:00:00 to 29-JUN-20 10:00:00 (CST-6)
Location: LONSDALE
Flood cause: Heavy Rain
Property damage: 0.00K
Crop damage: 0.00K
Reported by: State Official

Local officials closed Union Lake Trail between Garfield and Gonvick due to flood waters.

Heavy Rain in RENVILLE, MINNESOTA
From 28-JUN-20 18:00:00 to 29-JUN-20 06:00:00 (CST-6)
Location: BIRD ISLAND
Property damage: 0.00K
Crop damage: 0.00K
Reported by: CoCoRaHS

A trained spotter measured 7.56 inches of rainfall south of Bird Island, in less than 12 hours.