Tornadoes, Wind Damage and Flooding: August 14, 2020

mammatus clouds
Mammatus clouds as viewed west of the Twin Cities.
Courtesy: Lucas Graunke

Another round of storms brought tornadoes, wind damage and flooding across central and northern Minnesota on August 14, 2020.

Severe thunderstorms spawned multiple tornadoes during the afternoon and evening hours of Friday, August 14. At least eleven tornadoes touched down, mostly in central Minnesota. In addition, there were many reports of wind damage. The strongest tornado was rated EF1 about 3 three miles west of Glencoe and uprooted trees and damaged outbuildings. There were numerous photos and videos of this tornado shared on social media. A wind gust of 64mph was reported at the Twin Cities International Airport. As the storms departed over central Minnesota, the setting sun showcased spectacular mammatus clouds.

There was also wind damage and flooding reported in northern Minnesota. One tornado was reported in Aitkin County near Lawler and caused damage to trees and outbuildings. Heavy rains caused flooding in downtown Grand Rapids. One volunteer rain gage reader in Grand Rapids measured a two-day total of 6.83 inches.

Following are summaries of tornado and severe storm reports from the National Weather Service.

PUBLIC INFORMATION STATEMENT
NATIONAL WEATHER SERVICE TWIN CITIES/CHANHASSEN MN
701 PM CDT Tue Aug 18 2020
...NWS Damage Survey For 08/14/2020 Tornado Event...
.Overview...
Severe thunderstorms developed across Western Minnesota
Friday afternoon. These storms produced several tornadoes
across the region, as well as numerous reports of wind damage.
Survey results below are preliminary and not an exhaustive
list of all tornadoes that were reported. Additional surveys
may be conducted in the coming days. Thank you to all weather
spotters, public, media partners, and law enforcement that
relayed reports and helped build a Weather Ready Nation.
.Spicer/Green Lake Tornado...
Rating:                 EF-0
Estimated Peak Wind:    70 mph
Path Length /statute/:  3.40 miles
Path Width /maximum/:   50 yards
Fatalities:             0
Injuries:               0
Start Date:             Aug 14 2020
Start Time:             5:41 PM CDT
Start Location:         0.75 Miles S of Spicer, MN
Start Lat/Lon:          45.22/-94.94
End Date:               Aug 14 2020
End Time:               5:47 PM CDT
End Location:           Green Lake
End Lat/Lon:            45.24/-94.88
An NWS Survey found EF-0 tornado damage along and south of Green
Lake in Spicer, MN. In addition to several trees snapped, docks
along the lake sustained damage. There was a report of a restaurant
that lost its roof, but the surveyor was unable to contact the owner.
This path may be updated once more information becomes available.
.Kandiyohi/Meeker County Line Tornado...
Rating:                 EF-0
Estimated Peak Wind:    85 mph
Path Length /statute/:  2 miles
Path Width /maximum/:   50 yards
Fatalities:             0
Injuries:               0
Start Date:             Aug 14 2020
Start Time:             5:53 PM CDT
Start Location:         Near 195th St NE and 120th Ave NE
Start Lat/Lon:          45.24/-94.77
End Date:               Aug 14 2020
End Time:               5:58 PM CDT
End Location:           Near Crow River, MN
End Lat/Lon:            45.25/-94.73
An NWS Survey found EF-0 tornado damage along the Kandiyohi and
Meeker County line. Numerous trees were snapped or uprooted, however,
much of this path was inaccessible to surveyors. This track may be
updated once more information becomes available.
.Brownton, MN Tornado...
Rating:                 EF-0
Estimated Peak Wind:    85 mph
Path Length /statute/:  1.75 miles
Path Width /maximum/:   300 yards
Fatalities:             0
Injuries:               0
Start Date:             Aug 14 2020
Start Time:             5:45 PM CDT
Start Location:         2 Miles N Brownton, MN
Start Lat/Lon:          44.77/-94.34
End Date:               Aug 14 2020
End Time:               5:49 PM CDT
End Location:           3.5 Miles NE Brownton, MN
End Lat/Lon:            44.77/-94.30
An NWS Survey found damage consistent with an EF-0 tornado
in Mcleod County north of Brownton. Several trees were snapped,
a trailer was overturned, and a metal grain silo wall was damaged
and collapsed. There were numerous photos and videos of this tornado
shared on social media.
.Biscay/Glencoe, MN Tornado...
Rating:                 EF-1
Estimated Peak Wind:    95 mph
Path Length /statute/:  2.25 miles
Path Width /maximum/:   250 yards
Fatalities:             0
Injuries:               0
Start Date:             Aug 14 2020
Start Time:             5:50 PM CDT
Start Location:         3.5 Miles W Glencoe, MN
Start Lat/Lon:          44.79/-94.25
End Date:               Aug 14 2020
End Time:               6:01 PM CDT
End Location:           3 Miles NW Glencoe, MN
End Lat/Lon:            44.81/-94.21
An NWS Survey found damage consistent with an EF-1 tornado
in Mcleod County between Biscay and Glencoe. Maximum wind
speeds of 95 MPH snapped and uprooted several trees and
damaged outbuildings. There were numerous photos and videos
of this tornado shared on social media.
.Crystal, MN Tornado...
Rating:                 EF-0
Estimated Peak Wind:    75 mph
Path Length /statute/:  0.40 miles
Path Width /maximum/:   50 yards
Fatalities:             0
Injuries:               0
Start Date:             Aug 14 2020
Start Time:             7:55 PM CDT
Start Location:         Memory Lane Park
Start Lat/Lon:          45.04/-93.37
End Date:               Aug 14 2020
End Time:               7:57 PM CDT
End Location:           Near Douglas Dr and 44th Ave End
Lat/Lon:                45.04/-93.36
An NWS Survey indicated a brief EF-0 moved across the city of
Crystal, MN.The tornado started near Memory Lane Park, between
43rd and 44th Avenue North and Jersey Avenue North. A large tree
was uprooted at this location. This tornado moved eastward between
43rd and 44th Avenue and damaged several large trees, up to 4 feet
in diameter, along its path. The tornado lifted near Douglas Drive
North. Some roof damage occurred, but the majority of the trees and
large limbs fell on power lines, roads, and yards. There was also
damage on 45th Avenue North, but the damage was consistent with
downburst winds and more sporadic. The majority of the damage in
the broad area of New Hope, Crystal, North Minneapolis, and
Robbinsdale was from downburst winds.
.Waconia, MN Tornado...
Rating:                 EF-0
Estimated Peak Wind:    70 mph
Path Length /statute/:  0.30 miles
Path Width /maximum/:   50 yards
Fatalities:             0
Injuries:               0
Start Date:             Aug 14 2020
Start Time:             6:49 PM CDT
Start Location:         Rietz Lake
Start Lat/Lon:          44.84/-93.75
End Date:               Aug 14 2020
End Time:               6:50 PM CDT
End Location:           Just north of Airport Road
Lat/Lon:                44.84/-93.75
An NWS Survey indicated a brief EF-0, which was also observed by
people nearby. The tornado touched down just off shore on the
western edge of Reitz Lake, and moved inland. It caused damage
to a boat lift, boat, and several trees before dissipating just
north of Airport Road.
.Lincoln, MN Tornado...
Rating:                 EF-1
Estimated Peak Wind:    90 mph
Path Length /statute/:  5.92 miles
Path Width /maximum/:   200 yards
Fatalities:             0
Injuries:               0
Start Date:             Aug 14 2020
Start Time:             5:53 PM CDT
Start Location:         0.2 miles northwest of Big Lake
Start Lat/Lon:          46.15/-94.69
End Date:               Aug 14 2020
End Time:               6:01 PM CDT
End Location:           Just east of US-10 near Azure Road
Lat/Lon:                46.23/-94.64
An NWS survey found damage consistent with an EF-1 tornado in
northeastern Todd County about 6 miles west of Cushing. The tornado
touched down 0.2 miles northwest of Big Lake and traveled north-
northeast for nearly 6 miles. The tornado mainly uprooted trees, but
did minor damage to a couple of metal buildings in Lincoln before
dissipating.
.Ripley Township, MN Tornado...
Rating:                 EF-0 mph
Path Length /statute/:  5.82 miles
Path Width /maximum/:   200 yards
Fatalities:             0
Injuries:               0
Start Date:             Aug 14 2020
Start Time:             6:41 PM CDT
Start Location:         Near intersection of 213th St. and 175th Ave.
Start Lat/Lon:          46.07/-94.29
End Date:               Aug 14 2020
End Time:               6:51 PM CDT
End Location:           Just east of Jewel Road north of Fletcher Creek.
Lat/Lon:                46.12/-94.20
An NWS survey found damage consistent with an EF-0 tornado in
northern Morrison County about 7 miles northeast of Little Falls. It
traveled northeast for almost 6 miles snapping large tree branches,
uprooting trees and causing minor damage to a few outbuildings.
.Hillman, MN Tornado...
Rating:                 EF-0
Estimated Peak Wind:    80 mph
Path Length /statute/:  2.95 miles
Path Width /maximum/:   150 yards
Fatalities:             0
Injuries:               0
Start Date:             Aug 14 2020
Start Time:             6:09 PM CDT
Start Location:         2 miles SSE Hillman, MN
Start Lat/Lon:          45.97/-93.88
End Date:               Aug 14 2020
End Time:               6:12 PM CDT
End Location:           3.7 miles ESE Hillman, MN
Lat/Lon:                45.98/-93.82
An NWS survey found damage consistent with an EF-0 tornado in
eastern Morrison county about 2 miles southeast of Hillman. It
traveled east-northeast for nearly 3 miles uprooting trees along its
path.
.Farwell, MN Tornado...
Rating:                 EF-0
Estimated Peak Wind:    75mph
Path Length /statute/:  1.2 miles
Path Width /maximum/:   75 yards
Fatalities:             0
Injuries:               0
Start Date:             Aug 14 2020
Start Time:             4:17 PM CDT
Start Location:         0.5 miles S Farwell, MN
Start Lat/Lon:          45.74/-95.62
End Date:               Aug 14 2020
End Time:               4:19 PM CDT
End Location:           0.7 miles NE Farwell, MN
Lat/Lon:                45.76/-95.61
An NWS survey found damage consistent with an EF-0 tornado in Pope
County. The tornado travelled northeast for 1.2 miles, clipping the
town of Farwell. Large tree branches were broken and several power
poles were downed.
EF Scale: The Enhanced Fujita Scale classifies tornadoes into
the following categories.
EF0...Weak......65 TO 85 mph
EF1...Weak......86 TO 110 mph
EF2...Strong....111 TO 135 mph
EF3...Strong....136 TO 165 mph
EF4...Violent...166 TO 200mph
EF5...Violent...>200mph
NOTE:
The information in this statement is preliminary and subject to
change pending final review of the events and publication in
NWS Storm Data.

 

Modified August 19, 2020