Southerly winds brought hot and muggy weather conditions to the northern Plains and Upper Midwest, including northeast Minnesota, on Monday (July 21st).  A low pressure system was located in north central South Dakota by Monday evening, and its stationary front extended to the northeast through eastern North Dakota and Northwest Wisconsin.  Temperatures were in the middle 80s to low 90s in the warm sector, and the combination of dew point temperatures in the upper 60s to middle 70s resulted in heat indices in the 90s to 100s.  Thunderstorms developed during the late afternoon and early evening in western North Dakota and formed a mesoscale convective complex.  This MCV then became a derecho Monday evening as it moved and bowed east through eastern North Dakota and the northern Minnesota and northern Wisconsin late Monday and early Tuesday (July 22nd).  This derecho caused widespread wind damage from winds of at least 50 to 70 mph over much of northeast Minnesota, blowing and/or snapping trees and knocking out power.  There were more focused areas of structural damage that suggested there were winds in excess of 70 mph.  There were several injuries to campers in the Boundary Waters Canoe Area Wilderness due to falling trees, which required officials to make some rescues.

Thunderstorm Wind in ST. LOUIS, MINNESOTA
From 22-JUL-14 00:09:00 to 22-JUL-14 00:09:00 (CST-6)
Location: FLOODWOOD
Magnitude: 61.00 EG
Reported by: Trained Spotter

Trees were blown down.  One tree was 12 inches in diameter.

Thunderstorm Wind in ST. LOUIS, MINNESOTA
From 22-JUL-14 00:17:00 to 22-JUL-14 00:17:00 (CST-6)
Location: ALLEN
Magnitude: 61.00 EG
Reported by: Trained Spotter

Many trees between 6 and 12 inches in diameter were blown down in Hoyt Lakes.

Thunderstorm Wind in AITKIN, MINNESOTA
From 21-JUL-14 23:47:00 to 21-JUL-14 23:47:00 (CST-6)
Location: AITKIN
Magnitude: 61.00 EG
Reported by: Law Enforcement

Numerous trees were down throughout the county.

Thunderstorm Wind in ST. LOUIS, MINNESOTA
From 22-JUL-14 00:36:00 to 22-JUL-14 00:36:00 (CST-6)
Location: EVELETH
Magnitude: 61.00 EG
Reported by: Law Enforcement

Power lines were down along Routes 53 and 37.

Thunderstorm Wind in ST. LOUIS, MINNESOTA
From 22-JUL-14 01:29:00 to 22-JUL-14 01:29:00 (CST-6)
Location: DULUTH HGTS
Magnitude: 52.00 EG
Reported by: Public

There was a power outage.

Thunderstorm Wind in ST. LOUIS, MINNESOTA
From 22-JUL-14 00:24:00 to 22-JUL-14 00:24:00 (CST-6)
Location: EMBARRASS
Magnitude: 52.00 EG
Reported by: Law Enforcement

Trees and power lines were down.

Thunderstorm Wind in AITKIN, MINNESOTA
From 21-JUL-14 23:29:00 to 21-JUL-14 23:29:00 (CST-6)
Location: HILL CITY
Magnitude: 61.00 EG
Reported by: Law Enforcement

Trees were blown down.

Thunderstorm Wind in AITKIN, MINNESOTA
From 21-JUL-14 23:30:00 to 21-JUL-14 23:30:00 (CST-6)
Location: LIBBY
Magnitude: 61.00 EG
Reported by: Amateur Radio

Several trees about a foot in diameter were blown down.

Thunderstorm Wind in ST. LOUIS, MINNESOTA
From 22-JUL-14 00:03:00 to 22-JUL-14 00:03:00 (CST-6)
Location: CRANE LAKE
Magnitude: 61.00 EG
Reported by: Park/Forest Service

Campers were injured by a tree falling on their tent at a campsite on Lady Boot Bay on Lac La Croix Lake.  One young teenager was seriously injured with a broken pelvis and a dislocated shoulder.  A middle-aged man suffered a dislocated shoulder.

Thunderstorm Wind in ST. LOUIS, MINNESOTA
From 22-JUL-14 00:09:00 to 22-JUL-14 00:09:00 (CST-6)
Location: TWIG
Magnitude: 52.00 EG
Reported by: Public

The winds caused a power outage.

Thunderstorm Wind in KOOCHICHING, MINNESOTA
From 21-JUL-14 22:40:00 to 21-JUL-14 22:40:00 (CST-6)
Location: LITTLE FORK
Magnitude: 52.00 EG
Reported by: Public

Several trees were blown down.

Thunderstorm Wind in ST. LOUIS, MINNESOTA
From 22-JUL-14 00:22:00 to 22-JUL-14 00:22:00 (CST-6)
Location: ENDION
Magnitude: 52.00 EG
Reported by: Public

A large pine tree was blown down over the road near the intersection of Vermillion Road and Lakeview Drive in Duluth.

Thunderstorm Wind in KOOCHICHING, MINNESOTA
From 21-JUL-14 22:46:00 to 21-JUL-14 22:46:00 (CST-6)
Location: (INL)INTL FALLS ARPT
Magnitude: 70.00 EG
Property damage: 2.00K
Reported by: Public

More than 200 trees were blown down at a country club.  Parts of the roof from the outdoor deck by the clubhouse ended up on the number 18 tee.

Thunderstorm Wind in KOOCHICHING, MINNESOTA
From 22-JUL-14 00:38:00 to 22-JUL-14 00:38:00 (CST-6)
Location: PELLAND
Magnitude: 61.00 EG
Reported by: Public

A roof of a house was blown off near Pelland Junction.

Thunderstorm Wind in COOK, MINNESOTA
From 22-JUL-14 01:00:00 to 22-JUL-14 01:00:00 (CST-6)
Location: LUTSEN
Magnitude: 61.00 EG
Reported by: Emergency Manager

There was widespread tree damage near the end of the Gunflint Trail near Seagull Lake. Most damaged trees were blown down.

Thunderstorm Wind in ST. LOUIS, MINNESOTA
From 22-JUL-14 00:03:00 to 22-JUL-14 00:03:00 (CST-6)
Location: EVELETH MUNI ARPT
Magnitude: 70.00 EG
Reported by: Fire Department/Rescue

Many large trees were blown down.

Thunderstorm Wind in ST. LOUIS, MINNESOTA
From 22-JUL-14 00:03:00 to 22-JUL-14 00:03:00 (CST-6)
Location: VIRGINIA
Magnitude: 61.00 EG
Reported by: Public

A large tree was uprooted.

Thunderstorm Wind in ST. LOUIS, MINNESOTA
From 22-JUL-14 00:13:00 to 22-JUL-14 00:13:00 (CST-6)
Location: BIWABIK
Magnitude: 70.00 EG
Reported by: Trained Spotter

A dock on Embarrass Lake flipped over.  An 8 inch diameter tree snapped and fell on the dock.

Thunderstorm Wind in COOK, MINNESOTA
From 22-JUL-14 01:25:00 to 22-JUL-14 01:25:00 (CST-6)
Location: LUTSEN
Magnitude: 61.00 EG
Reported by: Emergency Manager

There was a widespread tree blow down near the end of Gunflint Trail near Seagull Lake.

Thunderstorm Wind in CARLTON, MINNESOTA
From 22-JUL-14 00:07:00 to 22-JUL-14 00:07:00 (CST-6)
Location: ESKO
Magnitude: 61.00 EG
Reported by: Public

A few trees about 6 inches in diameter were blown down.

Thunderstorm Wind in KOOCHICHING, MINNESOTA
From 21-JUL-14 22:48:00 to 21-JUL-14 22:48:00 (CST-6)
Location: INTERNATIONAL FALLS
Magnitude: 70.00 EG
Property damage: 1.00K
Reported by: Public

A carport and woodshed were blown down and destroyed.

Thunderstorm Wind in CROW WING, MINNESOTA
From 21-JUL-14 22:50:00 to 21-JUL-14 22:50:00 (CST-6)
Location: MISSION
Magnitude: 61.00 EG
Reported by: Public

A tree was blown down and a pontoon boat flipped on Horseshoe Lake.

Thunderstorm Wind in ST. LOUIS, MINNESOTA
From 22-JUL-14 00:02:00 to 22-JUL-14 00:02:00 (CST-6)
Location: SPRUCE
Magnitude: 78.00 EG
Reported by: Public

A couple structures just west of Highway 53 were damaged when thunderstorm winds tore off outside walls.

Thunderstorm Wind in ST. LOUIS, MINNESOTA
From 21-JUL-14 23:42:00 to 21-JUL-14 23:42:00 (CST-6)
Location: FLOODWOOD
Magnitude: 64.00 MG
Reported by: COOP Observer

Trees were blown down.

Thunderstorm Wind in AITKIN, MINNESOTA
From 21-JUL-14 23:47:00 to 21-JUL-14 23:47:00 (CST-6)
Location: HILL CITY
Magnitude: 61.00 EG
Reported by: Amateur Radio

An 8 inch diameter tree was blown down and blocking Highway 169.  The winds and damage caused power outages.

Thunderstorm Wind in ST. LOUIS, MINNESOTA
From 22-JUL-14 00:24:00 to 22-JUL-14 00:24:00 (CST-6)
Location: BABBITT
Magnitude: 52.00 EG
Reported by: Law Enforcement

Trees and power lines were blown down.

Thunderstorm Wind in ST. LOUIS, MINNESOTA
From 21-JUL-14 23:57:00 to 21-JUL-14 23:57:00 (CST-6)
Location: CRANE LAKE
Magnitude: 70.00 ES
Reported by: Park/Forest Service

Two campers were injured from a tree falling on their campsite on Loon Lake.

Thunderstorm Wind in KOOCHICHING, MINNESOTA
From 21-JUL-14 22:08:00 to 21-JUL-14 22:08:00 (CST-6)
Location: BIRCHDALE
Magnitude: 61.00 EG
Reported by: Public

Trees were blown down across County Road 86.

Thunderstorm Wind in ST. LOUIS, MINNESOTA
From 22-JUL-14 00:01:00 to 22-JUL-14 00:01:00 (CST-6)
Location: PEARY
Magnitude: 70.00 EG
Reported by: Public

A 25 inch diameter tree was blown down.

Thunderstorm Wind in ITASCA, MINNESOTA
From 21-JUL-14 23:47:00 to 21-JUL-14 23:47:00 (CST-6)
Location: MAX
Magnitude: 52.00 EG
Reported by: Amateur Radio

A 14 to 16 inch diameter tree was blown down.

Thunderstorm Wind in ST. LOUIS, MINNESOTA
From 22-JUL-14 00:03:00 to 22-JUL-14 00:03:00 (CST-6)
Location: EVELETH MUNI ARPT
Magnitude: 78.00 EG
Reported by: Fire Department/Rescue

There was damage at the Eveleth-Virginia Municipal Airport.  One hanger and the plane inside were destroyed.  Two other hangers were damaged.  One garage roof was blown off.

Thunderstorm Wind in CASS, MINNESOTA
From 21-JUL-14 22:26:00 to 21-JUL-14 22:26:00 (CST-6)
Location: FEDERAL DAM
Magnitude: 70.00 EG
Reported by: COOP Observer

Numerous trees were uprooted with some sheared off above the ground.  The power was out through at least the following afternoon.

Thunderstorm Wind in CROW WING, MINNESOTA
From 21-JUL-14 22:37:00 to 21-JUL-14 22:37:00 (CST-6)
Location: NISSWA
Magnitude: 61.00 EG
Reported by: Public

Many trees were blown down in Nisswa.

Thunderstorm Wind in ST. LOUIS, MINNESOTA
From 22-JUL-14 00:15:00 to 22-JUL-14 00:15:00 (CST-6)
Location: ARNOLD
Magnitude: 70.00 EG
Reported by: Public

A 6 to 12 inch diameter Aspen tree snapped.

Thunderstorm Wind in ST. LOUIS, MINNESOTA
From 22-JUL-14 00:15:00 to 22-JUL-14 00:15:00 (CST-6)
Location: AURORA
Magnitude: 61.00 EG
Reported by: Public

Many small trees and some large trees were blown down in Aurora.

Thunderstorm Wind in ST. LOUIS, MINNESOTA
From 22-JUL-14 00:18:00 to 22-JUL-14 00:18:00 (CST-6)
Location: BAYVIEW
Magnitude: 61.00 EG
Reported by: Public

A large tree was blown over and fell onto a fence.

Thunderstorm Wind in ST. LOUIS, MINNESOTA
From 22-JUL-14 00:34:00 to 22-JUL-14 00:34:00 (CST-6)
Location: BABBITT
Magnitude: 61.00 EG
Reported by: Public

Trees were uprooted and a large shed was destroyed.

Thunderstorm Wind in LAKE, MINNESOTA
From 22-JUL-14 01:04:00 to 22-JUL-14 01:04:00 (CST-6)
Location: FOREST CENTER
Magnitude: 61.00 EG
Reported by: Park/Forest Service

A camper was injured from a tree falling on the campsite.

Thunderstorm Wind in LAKE, MINNESOTA
From 22-JUL-14 01:04:00 to 22-JUL-14 01:04:00 (CST-6)
Location: FOREST CENTER
Magnitude: 61.00 EG
Reported by: Park/Forest Service

A camper was injured from a tree falling on the campsite.

Thunderstorm Wind in KOOCHICHING, MINNESOTA
From 21-JUL-14 22:50:00 to 21-JUL-14 22:50:00 (CST-6)
Location: LAUREL
Magnitude: 52.00 EG
Reported by: Law Enforcement

The winds knocked out the power.

Thunderstorm Wind in KOOCHICHING, MINNESOTA
From 21-JUL-14 23:09:00 to 21-JUL-14 23:09:00 (CST-6)
Location: SILVERDALE
Magnitude: 61.00 EG
Reported by: Trained Spotter

Trees were blown down.

Thunderstorm Wind in KOOCHICHING, MINNESOTA
From 21-JUL-14 22:50:00 to 21-JUL-14 22:50:00 (CST-6)
Location: LITTLE FORK
Magnitude: 52.00 EG
Reported by: Law Enforcement

The winds knocked out the power.

Thunderstorm Wind in ST. LOUIS, MINNESOTA
From 22-JUL-14 00:46:00 to 22-JUL-14 00:46:00 (CST-6)
Location: (ELO)ELY MUNI ARPT
Magnitude: 61.00 EG
Reported by: County Official

There was substantial tree damage on County Road 120 near the airport.  There were trees snapped off half way up the trunk.

Thunderstorm Wind in KOOCHICHING, MINNESOTA
From 21-JUL-14 23:18:00 to 21-JUL-14 23:18:00 (CST-6)
Location: SILVERDALE
Magnitude: 61.00 EG
Reported by: Trained Spotter

Trees were blown down.

Thunderstorm Wind in AITKIN, MINNESOTA
From 21-JUL-14 23:29:00 to 21-JUL-14 23:29:00 (CST-6)
Location: AITKIN
Magnitude: 61.00 EG
Reported by: Law Enforcement

Trees were blown down.