Power Outage in Missoula, MT

An outflow wind from a northerly moving thunderstorm produced strong to severe winds from roughly 6-7 pm MDT, with a peak gust of 64 mph at Missoula Intl. Airport. These winds caused downed trees and powerlines, and also damaged a roof. The outflow boundary snapped a tree north of Seeley Lake at 7 MDT. The first reported downed tree happened at 5:52 pm MDT in the Mullan Trail area. Additionally, a homeless camp in South Missoula suffered ripped tents.

Strong southerly outflow winds of 45 to 60 mph downed hundreds of live trees, primarily ponderosa and larch varieties. Most of the trees were uprooted but a few had tops blown out. The main area of damage extended from Salmon Lake to the Seeley Lake area with isolated areas of damage around the Morrell Falls trailhead and near Condon. Multi-hour power outages were common along with several vehicles damaged by fallen trees. In addition, hikers were stranded by fallen trees for a time at the Morrell Falls trailhead.

Strong southerly outflow winds of 45 to 60 mph downed hundreds of live trees, primarily ponderosa and larch varieties. Most of the trees were uprooted but a few had tops blown out. The main area of damage extended from Salmon Lake to the Seeley Lake area with isolated areas of damage around the Morrell Falls trailhead and near Condon. Multi-hour power outages were common along with several vehicles damaged by fallen trees. In addition, hikers were stranded by fallen trees for a time at the Morrell Falls trailhead.

Several large trees were uprooted and fell onto two cars and a house. The Missoula International Airport ASOS reported a gust to 48 mph while a sensor on top of Mount Sentinel recorded a 68 mph wind gust. A local power company reported at least 2,000 customers were without power for at least three hours.

Two transmission poles located in the South Hills area of Missoula were knocked out by the wind which caused a power outage. Multiple trees were pushed over by the wind including a 50 foot Ponderosa Pine tree that fell onto a home. A NWS employee reported that a Maple tree was snapped in half at the corner of Mount and Brooks Street.

The Missoula dispatch reported a lot of tree limbs down around town with numerous power lines down. A couple of lightning strikes started fires with one strike to a house in Missoula and a field in Florence. A private weather sensor located southeast of Lolo recorded a wind gust to 60 mph ahead of the main thunderstorm cells.

A macroburst brought damaging winds to the city of Missoula. A 74 mph wind gust was measured at the Missoula airport, but a majority of the damage occurred towards the |South Hills area. Major power lines and large trees were knocked down, and some residents were without power for four days. A local power company reported that several power poles, rated at 80 mph, were snapped in half. Over a million dollars in damages is estimated for this event.

The Missoula International airport ASOS reported a gust to 54 mph from the south-southeast direction. An intense thunderstorm near Florence produced a strong outflow that traveled north into the Missoula Valley causing multiple trees to be uprooted, downed power lines, & damage to a tent at the Western Montana Fair. The Missoula 911 dispatch reported at least 13 calls related to either power outages or lines down.

Power lines were reported down across Mullan Rd. Large tree branches were reported down at the Missoula Country Club golf course. Large trees were also reported down in the university district and along Daly Avenue.

A strong outflow boundary from thunderstorms moving north out of the Bitterroot Valley uprooted trees, created power outages, and damaged roofs.

An upper level wave tracked up from the Clearwater Mountains of Idaho towards the Seeley Lake area and initiated thunderstorms thanks to warmer than normal temperatures in the region. As these storms tracked over the Bitterroot and Clark Fork Valleys, they produced damaging winds and power outages. Also, a thunderstorm produced torrential rain and subsequent flash-flooding to Anaconda in southwestern Montana.

A cluster of thunderstorms developed at 3 pm MDT over Lemhi county and was associated with very frequent lightning strikes. This cluster of thunderstorms developed into a line and brought strong damaging winds to the Bitterroot and Missoula valleys. Numerous power lines were knocked down as a line of 60 mph winds push through the Bitterroot valley. As the thunderstorms approached Missoula, a macroburst developed and brought 74 mph wind gusts to the city of Missoula. Many power lines and trees were brought down and caused power outages for days in some areas.

A weak upper level low over southwestern Oregon brought moisture into western Montana on August 12th. A very weak mid-level wind maximum around 30 knots along with strong surface heating into the lower 90s and the lifting mechanism due to terrain helped to trigger multicellular thunderstorms that tracked into the Seeley Lake region. The main impacts of these storms were lightning, tree and power line damage.

A strong upper level wave moved into Washington State providing the necessary ingredients for a southwest flow severe thunderstorm event to setup. Very strong wind shear combined with meager instability and dew points in the 50s across north-central Idaho allowed for storms to develop in the afternoon. A few of these storms developed into supercells, one of which brought large hail and gusty winds to the Bitterroot Valley. A very strong cold front moved across Idaho into Western Montana by the evening hours providing gusty winds between 40 and 56 mph which brought down a few trees and power lines.

Strong thunderstorms brought severe winds with hail to Western Montana. Numerous areas saw fallen trees as large as 20 inches in diameter. There were also reports of signs and power lines downed sparking a small wildfire near Lolo.

Severe thunderstorms rolled across Western Montana bringing large hail that broke windshields, damaged roofs, and flattened crops. Some severe wind gusts were also reported including one that blew over three mature Douglas fir trees in the Silverbow area, and another that knocked tree branches onto power lines causing a power outage.

Wet spring storm brought moderate to locally heavy rain to West Central Montana and heavy snow to the Butte and Blackfoot Regions. The Missoula area received 1.79 to 2.11 inches of rainfall in a 24 hour period. Homeowners suffered leaking roofs and water seeping into basements because of rising groundwater. Urban flooding was reported in St. Ignatius and near Hamilton. Wet and heavy snowfall raised havoc for drivers on Interstate 90, downed trees that knocked power out in rural areas around Butte. The eastbound lane of Interstate 90 was shutdown for more than an hour as slick road conditions caused several semi-trailers to jackknife on Homestake Pass. Butte received a little over 7 inches of new snow, Elliston 8 inches, Stuart Mountain 8 inches and Snow Bowl Ski Resort a foot of new snow.

A late season thunderstorm event struck across portions of Western Montana. Winds were the main threat with these storms with trees being reported blow down onto power lines causing a fire north of Seeley Lake.

A line of thunderstorms moved across west central Montana during the evening hours, producing widespread outflow winds of 45 to 50 mph, with localized damaging winds of 60 to 70 mph. In Missoula County, thunderstorm winds blew down trees onto power lines and onto two vehicles causing power outages and damage to the vehicles. Near the confluence of Rock Creek and the Clark Fork River, thunderstorm winds of 71 mph caused roof damage and blew down trees. South of Seeley Lake, at the Boles Fire Camp, winds blew down tents. Near Dixon in Sanders County, thunderstorm winds of 59 mph caused roof damage to a trailer home. Power outages were reported in Ravalli County near Hamilton with trees blown down. In Mineral County, 50 mph winds caused the Fish Creek Fire to spread an additional 7000 acres, causing evacuation of homes in the Petty Creek area.

Scattered strong thunderstorms moved through west central Montana during the late afternoon and early evening hours, causing widespread damage from severe winds. In Missoula County, wind gusts to 58 mph blew down large tree branches onto power lines in Missoula and near Frenchtown. In the Seeley Lake area, over two dozen trees 12 inches in diameter, were blown down onto power lines, that also started fires. Wind gusts 60 to 64 mph were reported in Lake and Powell Counties, with thunderstorm winds blowing apart a shed and damaging a tin roof in the Ovando area. Tree damage and fire starts were reported up the Jocko River drainage. In Mineral County, 3/8 inch hail and wind gusts to 64 mph were reported near Deborgia.

Late afternoon severe thunderstorms developed over western Montana, with damaging winds and dime size hail reported in areas of Missoula, Lake, Flathead and Powell Counties. Dime size hail occurred in Missoula and Elliston. Damaging winds downed trees onto roads and power lines in Missoula, Arlee, Olney and northwest of Kalispell. A greenhouse was damaged in Arlee, and fires were started from downed power lines near Kalispell.

Strong thunderstorm winds gusting between 58 to 65 mph caused wind damage in northwest Montana during the evening hours. Most significant damage was on the west end of St. Regis in Mineral County, where numerous large pine trees fell down causing damage of $360,000. Fallen trees damaged a camper and 12 homes on Camels Hump Road. Twelve separate fires were started in Mineral County as trees fell onto power lines and roadways. Highway I-90 was temporarily closed due to fallen trees. A search and rescue worker was injured on I-90, when she was struck in the head by a four-inch diameter falling cottonwood branch. Wind damage was reported near Plains in Sanders County, where strong winds blew a barn off it's foundation 15 feet, and a garage was damaged by a fallen tree. Power outages and small fires were also reported by fallen trees onto power lines in Sanders, Missoula, Lake and Flathead Counties. In Kalispell, a section of awning along the roof line of Wendy's restaurant blew off onto two cars.

Strong thunderstorm winds blew through Missoula County during the afternoon. As the storm moved through Missoula, a tree fell onto a bicyclist who was knocked unconscious and injured. Power lines were also blown down in Missoula from the storm. As the thunderstorm moved to the northeast, wind gusts up to 71 mph were recorded with wind damage reported through the Swan Valley and 0.75 hail reported in Condon.

Wind damage occurred at the north end of Rock Creek near Clinton. Thunderstorm winds snapped trees in half with numerous branches broken and blown around. One tree fell onto a power line and started a fire with power outages reported.

Severe thunderstorms brought strong winds across Missoula County and large hail to Powell, Lake, and Flathead Counties. Heavy rain flooded basements in Polson, power was knocked out in the Missoula and northern Bitterroot Valleys, and hail up to golf ball-size was reported in Charlo.

Thunderstorms with strong winds and hail moved through western Montana during the late afternoon and evening hours. In Lolo and two miles south of Missoula, off duty NWS employees estimated wind speeds of 60 mph, which blew down a basketball hoop and mail boxes in Lolo. As the thunderstorm moved into Missoula, a wall cloud was reported by off duty NWS employee. As the thunderstorms continued to move through northwest Montana, damage was reported in Flathead and Sanders Counties where trees and power lines were blown down near Kalispell and Noxon, and from Ferndale to Columbia Falls along Highway 206. Strong thunderstorm winds caused damage in Lincoln County, where numerous trees were reported down in the Silver Butte and Middle Thompson Lake areas, and along Highway 37 outside of Libby. The hardest hit area was from Farm to Market Road from Libby Creek to near Granite Creek were hundreds of trees were uprooted and lying across yards and driveways, and across roof tops and some vehicles. In Yaak, a tree fell across the highway pinning a passing motorist in her car. The woman was transported to St. John's Hospital in Libby. In Libby, a road sign was blown down and a roof was blown off a building and almost hit a car. Later in the evening, one inch hail was reported in Pinnacle in Flathead County.

50 to 60 mph thunderstorm wind gusts at the Missoula airport blew down storage area wall next to NWS office. Report of minor roof damage in Ovando in Powell County from thunderstorm winds. Billboard blown down along HWY 93 near Evaro Hill in Missoula County. Thunderstorm wind gusts 50 to 60 mph blew down 50 foot-tall pine tree onto two men at Echo Lake near Bigfork in Flathead County. 59 year old man died from the accident, and his son received injuries to his shoulder. Thunderstorm winds caused damage from Bigfork to Columbia Falls, where two cars were hit by falling trees and power lines were brought down by 50 to 60 mph wind gusts.