2011 Goderich, Ontario tornado
Encyclopedia
The 2011 Goderich, Ontario tornado (rated as an F3 on the Fujita Scale
Fujita scale
The Fujita scale , or Fujita-Pearson scale, is a scale for rating tornado intensity, based primarily on the damage tornadoes inflict on human-built structures and vegetation...

) was caused by an isolated supercell
Supercell
A supercell is a thunderstorm that is characterized by the presence of a mesocyclone: a deep, continuously-rotating updraft. For this reason, these storms are sometimes referred to as rotating thunderstorms...

 which tore across Huron County, Ontario
Huron County, Ontario
Huron County is a census division and county of the province of Ontario, Canada. It is located on the southeast shore of its namesake, Lake Huron, in the southwest part of the province...

 on the afternoon of Sunday, August 21, 2011. Beginning as a tornadic waterspout
Waterspout
A waterspout is an intense columnar vortex that occurs over a body of water and is connected to a cumuliform cloud. In the common form, it is a non-supercell tornado over water. While it is often weaker than most of its land counterparts, stronger versions spawned by mesocyclones do occur...

 over Lake Huron
Lake Huron
Lake Huron is one of the five Great Lakes of North America. Hydrologically, it comprises the larger portion of Lake Michigan-Huron. It is bounded on the east by the Canadian province of Ontario and on the west by the state of Michigan in the United States...

, the tornado ripped through the lakeside town of Goderich
Goderich, Ontario
Goderich is a town in the Canadian province of Ontario and is the county seat of Huron County. The town was founded by William "Tiger" Dunlop in 1827. First laid out in 1828, the town is named after Frederick John Robinson, 1st Viscount Goderich, who was British prime minister at the time. The town...

 severely damaging the historic downtown and homes in the surrounding area. One person died and 37 more were injured as a result. This was the strongest tornado to hit Ontario
Ontario
Ontario is a province of Canada, located in east-central Canada. It is Canada's most populous province and second largest in total area. It is home to the nation's most populous city, Toronto, and the nation's capital, Ottawa....

 in over fifteen years, since the April 20, 1996 tornado outbreak in Williamsford
Williamsford, Ontario
Williamsford is a village on the North Saugeen River in Grey County, Ontario, Canada . It has a general store, post office, a bookstore and restaurant housed in a historic grain mill. A small dam controls the North Saugeen River. It has several churches, and a community cemetery. Williamsford also...

, Arthur
Arthur, Ontario
Arthur is a community located just north of Hwy 6 and Wellington Road 109 in the township of Wellington North, Ontario, Canada. Formerly an independent village, Arthur was amalgamated into Wellington North on January 1, 1999.-History:...

, and Violet Hill.

Antecedent conditions

There was little hint of what was to come that day as far as severe weather
Severe weather
Severe weather phenomena are weather conditions that are hazardous to human life and property.- Examples Include :Severe weather can occur under a variety of situations, but three characteristics are generally needed: a temperature or moisture boundary, moisture, and , instability in the...

 was concerned. Both Environment Canada
Environment Canada
Environment Canada , legally incorporated as the Department of the Environment under the Department of the Environment Act Environment Canada (EC) (French: Environnement Canada), legally incorporated as the Department of the Environment under the Department of the Environment Act Environment...

 in Toronto
Toronto
Toronto is the provincial capital of Ontario and the largest city in Canada. It is located in Southern Ontario on the northwestern shore of Lake Ontario. A relatively modern city, Toronto's history dates back to the late-18th century, when its land was first purchased by the British monarchy from...

 and the Storm Prediction Center
Storm Prediction Center
The Storm Prediction Center , located in Norman, Oklahoma, is tasked with forecasting the risk of severe thunderstorms and tornadoes in the contiguous United States. The agency issues convective outlooks, mesoscale discussions, and watches as a part of this process...

 in Oklahoma
Oklahoma
Oklahoma is a state located in the South Central region of the United States of America. With an estimated 3,751,351 residents as of the 2010 census and a land area of 68,667 square miles , Oklahoma is the 28th most populous and 20th-largest state...

 outlined the risk for non-severe thunderstorms that day across the lower Great Lakes
Great Lakes
The Great Lakes are a collection of freshwater lakes located in northeastern North America, on the Canada – United States border. Consisting of Lakes Superior, Michigan, Huron, Erie, and Ontario, they form the largest group of freshwater lakes on Earth by total surface, coming in second by volume...

. Lapse rates yielded limited instability for severe weather, with a secondary cold front
Cold front
A cold front is defined as the leading edge of a cooler mass of air, replacing a warmer mass of air.-Development of cold front:The cooler and denser air wedges under the less-dense warmer air, lifting it...

 acting as a trigger. Given the much colder air aloft (freezing levels near 700 hPa) coupled with surface heating there was the risk for small hail
Hail
Hail is a form of solid precipitation. It consists of balls or irregular lumps of ice, each of which is referred to as a hail stone. Hail stones on Earth consist mostly of water ice and measure between and in diameter, with the larger stones coming from severe thunderstorms...

 and gusty outflow winds, which was also mentioned. Though some upper-level wind field parameters were sufficient for tornadic activity, they were marginal at best when coupled with the synoptic pattern at hand (a highly atypical pattern compared to previous major tornado events in the lower Great Lakes region).

By 11:00am that morning, showers and thunderstorms began to develop over southwestern Ontario. Initially they were weak, but began to intensify in some localized areas. Hail and heavy rain
Rain
Rain is liquid precipitation, as opposed to non-liquid kinds of precipitation such as snow, hail and sleet. Rain requires the presence of a thick layer of the atmosphere to have temperatures above the melting point of water near and above the Earth's surface...

 came down with a line of storms tracking from northwest of Kitchener
Kitchener, Ontario
The City of Kitchener is a city in Southern Ontario, Canada. It was the Town of Berlin from 1854 until 1912 and the City of Berlin from 1912 until 1916. The city had a population of 204,668 in the Canada 2006 Census...

 toward the Brampton
Brampton, Ontario
Brampton is the third-largest city in the Greater Toronto Area of Ontario, Canada and the seat of Peel Region. As of the 2006 census, Brampton's population stood at 433,806, making it the 11th largest city in Canada. It is also one of Canada's fastest growing municipalities, with an average...

 area early that afternoon
Afternoon
Afternoon is the time of day from noon to about 18:00.The term should not be confused with "after noon" , which is a translation of the Latin "post meridiem" as used in the 12-hour clock, meaning a time of day from noon to midnight.In Australia and New Zealand, the word "arvo" is a slang term for...

. There were reports of localized flooding and marginally damaging wind gusts associated with these storms. A brief tornado was also reported in Gananoque
Gananoque, Ontario
Gananoque is a town in Leeds and Grenville County, Ontario, Canada. The town had a population of 5,287 year-round residents in the Canada 2006 Census, as well as summer residents sometimes referred to as "Islanders" because of the Thousand Islands in the St. Lawrence River, Gananoque's most...

 at 12:45pm. Later confirmed as an F1, this tornado caused minor damage in an area 1.5 kilometres long and 60 metres wide. Environment Canada issued a severe thunderstorm watch for most of southern Ontario as a result. The town of Goderich and surrounding areas of Huron County were included.

At around the same time, an intense thunderstorm had developed over northern Michigan
Michigan
Michigan is a U.S. state located in the Great Lakes Region of the United States of America. The name Michigan is the French form of the Ojibwa word mishigamaa, meaning "large water" or "large lake"....

 in Alcona County
Alcona County, Michigan
Alcona County is a county of the U.S. state of Michigan. As of the 2000 census, the population is 11,719. Its county seat is Harrisville. Alphabetically it is the first county in Michigan, as its flag states "First of the 83".-History:...

. Hail of up to two inches in diameter was reported to the National Weather Service
National Weather Service
The National Weather Service , once known as the Weather Bureau, is one of the six scientific agencies that make up the National Oceanic and Atmospheric Administration of the United States government...

 and a velocity couplet appeared on Doppler weather radar at around 1:30pm. A tornado warning was subsequently issued, but the storm moved out over the relatively warm waters of Lake Huron shortly after. It weakened for a time, but began to intensify once again as it crossed the border into Canada by 3:00pm. Strong rotation began to develop on the southwest side of this thunderstorm as resolved by velocity images on the radar
Weather radar
Weather radar, also called weather surveillance radar and Doppler weather radar, is a type of radar used to locate precipitation, calculate its motion, estimate its type . Modern weather radars are mostly pulse-Doppler radars, capable of detecting the motion of rain droplets in addition to the...

 of Canadian weather radar network
Canadian weather radar network
The Canadian weather radar network consists of 31 weather radars spanning Canada's most populated regions. Their primary purpose is the early detection of precipitation, its motion and the threat it poses to life and property...

 in Exeter, and a textbook-style hook echo
Hook echo
The hook echo is one of the classical hallmarks of tornado-producing supercell thunderstorms as seen on a weather radar. The echo is produced by rain, hail, or even debris being wrapped around the supercell...

 soon appeared on reflectivity images too (see image to left). With the powerful storm closing in on Goderich from the northwest at approximately 75 km/h, Environment Canada issued a tornado warning at 3:48pm. The meteorologists estimated the storm would make landfall there in approximately ten minutes.

Text of the Goderich tornado warning


664
WFCN11 CWTO 211948
TORNADO WARNING
ISSUED BY ENVIRONMENT CANADA
AT 3:48 PM EDT SUNDAY 21 AUGUST 2011.
---------------------------------------------------------------------
TORNADO WARNING FOR:NEW= STRATFORD - MITCHELL - SOUTHERN PERTH COUNTY.

---------------------------------------------------------------------

DISCUSSION

AT 3:30 PM EDT A SEVERE THUNDERSTORM IS OCCURRING OVER SOUTHERN LAKE
HURON. THIS THUNDERSTORM IS MOVING TO THE SOUTHEAST AT 75 KM/H AND
WILL MAKE LANDFALL NEAR GODERICH ABOUT 4 PM. THIS THUNDERSTORM HAS A
HISTORY OF PRODUCING TORNADOES.

SEVERE THUNDERSTORMS LIKELY PRODUCING TORNADOES ARE IMMINENT OR
OCCURRING IN THE AREA. LARGE HAIL, DAMAGING WINDS AND HEAVY RAINFALL
MAY ALSO ACCOMPANY THESE STORMS.

MONITOR WEATHER CONDITIONS AND TAKE IMMEDIATE SAFETY PRECAUTIONS IF
THREATENING WEATHER APPROACHES.

END/OSPC



Unfortunately, Huron County does not presently have a network of tornado sirens in place, unlike some other Ontario municipalities. As a result, the tornado took most area residents by surprise despite the twelve minute lead time of the tornado warning. The relatively low casualty rate was attributed to the fact that an earlier thunderstorm had cleared downtown Goderich of hundreds of market-goers attending a weekend festival, most of whom were still outdoors as little as two hours before the tornado struck.

The tornado's track

In the minutes prior to 4:00pm, the tornadic supercell was closing in on the Lake Huron shoreline. Photos and video of these initial moments reveal no funnel, merely a thick, rotating wall of rain curtains. Not unlike the all-but-forgotten Barrie tornado in 1985, this storm was also heavily rain-wrapped. Moving on to land by 4:00pm, the tornado made its first destructive appearance at the Sifto
Sifto Canada
Sifto Canada is a salt mining and marketing company based in Canada, with its primary products being table salt, fine evaporated salt, water conditioning salt, agricultural salt, coarse salt, rock salt, and bulk salt...

 Salt mine located on Indian Island at the mouth of the Maitland River
Maitland River
The Maitland River is a river in southwestern Ontario, Canada, which empties into Lake Huron in the town of Goderich, Ontario. The river is 150 km in length....

. It proceeded to tear large portions of roof from the salt storage domes, in addition to some of the brick outbuildings at the facility. Pieces of sheet metal were also ripped from some of the higher-profile structures, such as the salt evaporator. A 61-year old boom operator was at his post on the mine that day. Used for loading containers on to ships, the high profile of the boom provided pale shelter from the powerful winds. Unfortunately, the Lucknow
Lucknow, Ontario
Lucknow is a community located in Bruce County, Ontario, Canada. It is incorporated in the Township of Huron-Kinloss.-History:...

 native was killed when his boom inevitably collapsed during the tornado. Crossing the river, the tornado tore more sheet metal from the upper portion of a nearby grain elevator before plowing up the bluff
Bluff
Bluff may refer to:* a type of deception* an empty boast-Geography:* a very steep and broad hill or small cliff, frequently next to a river or ocean*feeder bluffAustralia* Bluff, Queensland, a town in QueenslandCanada...

 overlooking Lake Huron, in a swath several hundred metres wide.
The tornado then set its sights on the neighbourhood immediately northwest of Goderich's downtown
Downtown
Downtown is a term primarily used in North America by English speakers to refer to a city's core or central business district ....

 core, especially those in the Waterloo Street and St. Georges Crescent area, closest to the immediate edge of the bluff. Power poles and trees were snapped or uprooted in addition to many homes either losing their roofs or sustaining further structural damage after initial roof loss. The historic octagonal downtown, housing century-old brick buildings, was hardest hit by this tornado. Most buildings suffered at the very least, blown out windows, including the sturdy and relatively unscathed Huron County courthouse. Others were not so lucky as roofs were completely torn off, leaving little structural integrity to face the wind. The upper floors of several of these buildings were completely destroyed. The remaining loose brick and mortar fascia collapsed, crushing vehicles and other similarly-sized objects. Vehicles parked in more open areas were subsequently overturned or impaled by flying debris
Debris
Debris is rubble, wreckage, ruins, litter and discarded garbage/refuse/trash, scattered remains of something destroyed, or, in geology, large rock fragments left by a melting glacier etc. The singular form of debris is debris...

, trees were removed of most of their limbs with sheet metal and other foreign objects wrapped around them. Immediately surrounding the downtown, a church built in 1878 (see photograph to left) at the intersection of Kings Highway 21
Highway 21 (Ontario)
King's Highway 21, commonly referred to as Highway 21, is a provincially maintained highway in the Canadian province of Ontario that begins at Highway 402 mid-way between Sarnia and London and ends at Highway 6, Highway 10 and Highway 26 in Owen Sound...

 and St. David Street was severely damaged. A carwash facility adjacent to the church suffered a similar fate. Three people were injured at the carwash when the roof was torn off and the bays underneath became exposed to the wind. A van with two people inside had its windows smashed out when debris wrapped itself around it. Another man on a Harley-Davidson
Harley-Davidson
Harley-Davidson , often abbreviated H-D or Harley, is an American motorcycle manufacturer. Founded in Milwaukee, Wisconsin, during the first decade of the 20th century, it was one of two major American motorcycle manufacturers to survive the Great Depression...

 motorcycle had both his legs broken when he became pinned between his bike and a collapsed wall from one of the bays. The three had been seeking shelter from the storm at that time, mainly from the golfball to baseball size hail that preceded the tornado.
Crossing Kings Highway 21, the tornado moved into the easternmost residential areas of Goderich, north of Elgin Street. More homes sustained significant damage here, with most of those affected receiving some form of roof or window damage. Those with clapboard
Clapboard
Clapboard may refer to:*Clapboard , a building material*Clapperboard, a film production tool...

 siding had pock marks and some of their paint stripped. Other homes lost vast portions of their roofs and commercial buildings near Oxford Street and Maitland Road had partial roof removal and exterior wall damage. Some of these walls partially collapsed, crushing more vehicles. Timber
Timber
Timber may refer to:* Timber, a term common in the United Kingdom and Australia for wood materials * Timber, Oregon, an unincorporated community in the U.S...

 power poles were snapped, and concrete light posts were partially toppled near this location. Moving to the east-southeast, the tornado left Goderich, on its way toward the hamlet of Benmiller
Benmiller, Ontario
Benmiller, Ontario is a community located in the northwestern part of Huron County in Ontario, Canada, and the place where the Benmiller Blanket was made....

 approximately 8 kilometres away. Now emerging from the rain curtains as a menacing, stovepipe-shaped funnel, and roughly following the Maitland River, the tornado's path widened. In this mostly rural area, there was extensive tree damage in a swath about 1 kilometre wide. Passing through Benmiller it caused extensive damage to several more structures, including the Benmiller Inn. Large swaths of trees were downed on both sides of the Maitland River on the south end of town, in addition to those on the north side. Structural debris from Benmiller was deposited into the river. The damage became more erratic as the tornado crossed uneven terrain, as those objects on higher ground were more severely damaged.

Leaving Benmiller, the tornado entered into a more rural area once again, as it began to enter its final stages. Many tree limbs were removed by the tornado in addition to it toppling the trees themselves. The damage path also became more evident as it passed through open cornfields, downing large swaths of corn in an area about 200 metres wide. Crossing Sharpes Creek Line (Huron Road 31) there was more tree and corn damage by the tornado, though it was becoming increasingly weaker and sporadic in nature. The tornado eventually dissipated in the open fields between Base Line (Huron Road 8) and London Road (Kings Highway 4
Highway 4 (Ontario)
King's Highway 4, also known as Highway 4, is a provincially maintained highway in the Canadian province of Ontario. Originally much longer than its present length, more than half of Highway 4 was transferred to the responsibility of local governments in 1998. In its present form, it travels...

), southwest of the village of Londesborough, after some 15 to 20 kilometres on the ground.

Aftermath

Following the tornado, one person was dead and 37 more were injured along the tornado's track from Lake Huron to near Londesborough. In the hours following the disaster, the Ontario Provincial Police
Ontario Provincial Police
The Ontario Provincial Police is the Provincial Police service for the province of Ontario, Canada.-Overview:The OPP is the the largest deployed police force in Ontario, and the second largest in Canada. The service is responsible for providing policing services throughout the province in areas...

 closed all roads leading into Goderich in order to allow streets to be cleared of debris, and to deal with the numerous gas leaks across the town of 8,000. Town officials quickly declared a state of emergency
State of emergency
A state of emergency is a governmental declaration that may suspend some normal functions of the executive, legislative and judicial powers, alert citizens to change their normal behaviours, or order government agencies to implement emergency preparedness plans. It can also be used as a rationale...

 as urban search and rescue teams combed the town for missing individuals. Fortunately, nobody was left unaccounted for in spite of the severe damage. The day after the storm, Ontario Premier Dalton McGuinty
Dalton McGuinty
Dalton James Patrick McGuinty, Jr., MPP is a Canadian lawyer, politician and, since October 23, 2003, the 24th and current Premier of the Canadian province of Ontario....

 visited Huron County and pledged $5 million in disaster assistance from the province of Ontario. Local hardware stores also donated many of their products to assist in the recovery effort. A local relief fund has also been set up, entitled the Goderich Disaster Relief Fund, in which anyone can make a donation at chartered banks and the Goderich Community Credit Union.

In the days following the storm, as power was restored, roads became passable, and damaged structures shored up, local public works crews established fencing and concrete barriers around the entire perimeter of historic downtown Goderich to prevent trespassing. The Ontario Provincial Police are also continuing to patrol that location, barring anyone other than those contracted for cleanup efforts to stay out of this restricted area. As of the end of August 2011, the question of restoration of many of the oldest structures in Goderich is still one of debate. The recovery process is ongoing, and will take many months or potentially years to fully complete. The Insurance Bureau of Canada estimates the tornado caused $75 million in damage, but the Mayor of Goderich estimates the total bill will top $100 million.
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