EF1 Tornado — Martin, Minnesota

2018-09-20 · near Granada, Martin, Minnesota

Event narrative

A NWS Storm survey confirmed an EF1 tornado developed just west of the City of Granada, and tracked eastward for 5.3 miles as it moved into Faribault County. The average width was 220 yards and damaged several homes in Granada, before moving across farmland to the east. Numerous large trees were uprooted or blown down. The damage in Granada was consistent with EF1 damage as large sections of roof structures were removed, and one house was shifted from its foundation. Highest winds were estimated at 105 mph.

Wider weather episode

A violent outbreak of significant straight line winds, downburst winds, and multiple tornadoes occurred during the afternoon and early evening across southern Minnesota.

During the afternoon of Thursday, September 20th, a warm front lifted northward across far southern Minnesota. By the late afternoon, the warm front lied from just south of the Minnesota River, northeast to around the city of Wabasha.

Several thunderstorms developed in southwest Minnesota, and northwest Iowa. These storms moved into far southern Minnesota and quickly intensified and raced off to the east-northeast along, and north of this warm front.

Damage reports started to come into the office around 4 PM CST in Martin County, with multiple reports of significant damage from south of Mankato, to Waseca, then northeast through Waterville, Morristown, Owatonna, Faribault, Northfield, Cannon Falls, and Red Wing before moving into west central Wisconsin.

A long, and several day storm survey indicated at least XX confirmed tornadoes occurred in a widespread area of damaging winds from Martin County, northeast into west central Wisconsin.

The most destruction part of the storm occurred around Waterville, Morristown, Owatonna, Faribault and Cannon Falls. These cities all reported homes, buildings and warehouses either damaged or destroyed.

Hundreds of large, mature trees were uprooted or snapped along this path of destruction, including numerous trees up to 4 feet in diameter. In addition to the trees, structural damage was widespread including the Faribault airport where 80 planes were either damaged or destroyed as hangers were blown off their foundation.

The towns of Waterville and Faribault had the most homes damaged which was associated with EF2 tornado damage.

Two miles west of the Faribault airport, a resort area on Roberds Lake had upwords of 75 percent of the trees uprooted or blown down on the east side of the lake. Some of the trees landed on homes and split them in half.

View location on OpenStreetMap → (43.6980, -94.3530)

Source: NOAA Storm Events Database, event_id 779127. Narrative written by the NWS forecast office that issued the report.