Английская Википедия:2007 Elie tornado

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During the evening of June 22, 2007, a powerful F5 tornado struck the town of Elie, in the Canadian province of Manitoba (Шаблон:Convert west of Winnipeg). It was part of a small two-day tornado outbreak that occurred in the area and reached a maximum width of Шаблон:Convert. The tornado was unusual because it caused the extreme damage during its roping out stage at a mere Шаблон:Convert in width and moved extremely slowly and unpredictably. The tornado tracked primarily southeast, as opposed to the usual northeast, and made multiple loops and sharp turns. Because Environment Canada adopted the Enhanced Fujita scale in 2013, there will be no more tornadoes with an F5 rating, making this tornado the first and last confirmed F5 tornado in Canada.

While several houses were leveled, no one was injured or killed by the tornado. A home in the town was swept clean off of its foundation, justifying the F5 classification. One of the strongest twisters on record since 1999, it is one of only ten to be rated F5/EF5 since 1999 in North America. The tornado caused damage of an estimated $39 million.

Meteorological synopsis

Файл:Radar image of the storms that produced the tornado.png

Radar image of the group of storms that produced the tornado.

The synoptic situation on June 22 was conducive to a major severe weather event in southern Manitoba. A low pressure system came in from Saskatchewan through the day, and then moved over southern Manitoba throughout the evening. A warm front was positioned north of Elie for much of the day with a trailing cold front residing west of Elie near the Lake Manitoba basin southwest through southeast Saskatchewan. A lake breeze boundary was also present south of Lake Manitoba.

Very warm air was situated over Southern Manitoba that day as temperatures climbed into the high 20s °C (low 80s °F). The humidity was also uncomfortably high, with dewpoints ranging from Шаблон:Convert. Strong wind shear was present, reflected in high helicity values. These conditions were favorable for supercells, which are thunderstorms with rotating updrafts, and they developed within the warm sector located in the Red River Valley and areas farther west. The situation was exacerbated by the presence of the lake breeze boundary because the atmosphere was capped through much of the day with little in the way of a trigger. This boundary provided the focus for storms to develop rapidly and become severe, given the high instability present.

Storm track and damage

Файл:F5 tornado funnel cloud Elie Manitoba 2007.jpg

Funnel cloud that would produce the Elie tornado.

The tornado initially touched down north of the Trans-Canada Highway around 6:25 p.m. CDT (23:25 UTC) and slowly moved southeast where it picked up and overturned a semi trailer and a tractor trailer. The tornado slowly turned east, took a sharp turn south, and then took another sharp turn east all within roughly Шаблон:Convert. The tornado made another turn south and made an extremely slow loop over the town's flour mill at F2 intensity, causing over $1 million in damage. Multiple semi trucks were overturned and damaged and building walls buckled inward. At this point, the tornado was producing F1 to F2 level damage and had grown to a width of 50 m. From there, it headed south, parallel to Janzen Road, at F0 intensity. It also continued to grow, and reached its peak width of about 140 m. After reaching the intersection of Jansen Road and Road 61 North, the tornado turned east directly towards the southwest edge of Elie. It quickly intensified to F4 strength while it made a loop over Elie Street. Here, it damaged a dozen homes and destroyed four houses, including one which was described as well-built and bolted to its foundation, being lifted completely off its foundation and thrown into the air where it then broke apart, justifying F5 intensity. The tornado was even strong enough to rip some sill plates and snap off bolts that supported them. Trees were debarked as well. The two other houses sustained F4 level damage, with both of them being almost completely lifted off of their foundations. One other house also sustained F2 or F3 level damage, with the entire roof torn off and multiple exterior walls collapsed. The tornado also flipped and threw multiple cars, including a car that was tossed over 100 meters, and even tossed one homeowner's Chrysler Fifth Avenue onto a neighbor's roof. The tornado lingered over this area of Elie for approximately four minutes before it exited Elie to the southwest and rapidly dissipated.

Файл:Updated tornado track of Elie, Manitoba 2007 F5.png

Path of the tornado, showing sporadic loops and turns.

The tornado traveled about Шаблон:Convert and was Шаблон:Convert wide at its widest during its 35-minute lifespan. The tornado repeatedly struck essentially the same area of town, destroying most of the structures and vehicles in the area. A video of the tornado shows an entire two-story home swiped off its foundation and tossed Шаблон:Convert in the air before rotating around the tornado and then being obliterated. Also seen on the video was a three-quarters-of-a-ton GM van filled with drywall picked up and tossed hundreds of feet. At least three houses are seen being destroyed on the video, with many more being damaged as well as vehicles, and the mill is seen being damaged, with bins and roofs being destroyed there.

Aftermath

Since the people in Elie were prepared and took the necessary precautions during the event, no one was injured or killed during the storm. The following day, Environment Canada sent out a storm damage survey team from the Prairie and Arctic Storm Prediction Centre to assess the damage caused by the tornado. On September 18, 2007, the tornado was upgraded to F5 on the Fujita scale from the original F4 based on video analysis of the tornado and reassessment of the damage. This was the first tornado in Canada to be officially rated as such, making it the strongest confirmed tornado in Canadian history. It was one of only two F5/EF5 tornadoes that year (the other being in Greensburg, Kansas on May 4, 2007), and there have only been ten confirmed since 1999. At the time, Canada had not adopted the Enhanced Fujita scale.

Rating disputes

Many peopleШаблон:Who argued that the tornado was only being rated an F5 for novelty's sake,Шаблон:Citation needed but further research found clear F5 damage with a single house being wiped cleanly off its foundation. Surveyors were hesitant to rate the tornado so high because its peculiar slow forward speed could mean that it was a less intense tornado that stood still over the same area for a long period of time, and that it hadn't reached F5 intensity. This uncertainty resulted in the tornado's initial F4 rating. Analysis of civilian video however, found the tornado crossed F5-damaged area for no more than 30 seconds, making it a clear F5-intensity tornado. Video analysis also observed rotation in a manner indicative of windspeed well over Шаблон:Convert.Шаблон:Citation needed

Significance

At the same time as the Elie tornado, another tornado was occurring close to nearby Oakville. That tornado was rated as an F3 with winds of Шаблон:Convert after it destroyed several outbuildings, a couple of grain storage bins, and many trees. The Elie tornado was also significant because of how it looked while at F5 intensity. The tornado was reaching the end of its life span and was in its roping out/decaying stage. Some meteorologists suggest the intensity was due to the rapid implosion of the tornado's wind field, which caused it to quickly accelerate for a brief period of time.

Other tornadoes

In addition to the Elie F5 tornado, four more tornadoes also affected Canada on June 22–23. Шаблон:Tornado Chart

List of confirmed tornadoes – Friday, June 22, 2007, to Saturday, June 23, 2007

F#	Location	County / Parish	Province	Start Coord.	Date	Time (UTC)	Path length	Max width	Summary
bgcolor="Шаблон:Storm colour" | F3	Oakville area	Central Plains	MB	Шаблон:Coord	June 22	23:51	Шаблон:Convert	Unknown	After the Elie tornado dissipated, a new destructive tornado developed about Шаблон:Convert west of there. The tornado tracked through the country damaging trees, outbuildings, and a couple of grain storage bins.
bgcolor="Шаблон:Storm colour" | F1	ESE of Lampman	Saskatchewan	SK	Шаблон:Coord	June 23	18:04	Шаблон:Convert	Шаблон:Convert	This small tornado caused C$100,000 in damage along its path and injured one person.
bgcolor="Шаблон:Storm colour" | F0	NE of Carnduff	Saskatchewan	SK	Шаблон:Coord	June 23	18:38	Unknown	Unknown	Brief tornado with no known damage.
bgcolor="Шаблон:Storm colour" | F3	NW of Pipestone to near Glenora	Pipestone	MB	Шаблон:Coord	June 23	18:58	Шаблон:Convert	Шаблон:Convert	This large wedge tornado completely destroyed two homes and damaged many trees and several wheat fields. Damage amounted to C$2 million. This tornado was captured on camera, with dramatic footage of the formation, intensification, and even when the tornado displayed multiple vortices, available online.

See also

• Tornadoes of 2007
• List of Canadian tornadoes and tornado outbreaks
• List of F5 and EF5 tornadoes
• Tornado outbreak of May 4–6, 2007 – Produced the Greensburg, Kansas EF5 tornado

External links

• Video of tornado
• Popular Manitoba tornado video
• The Elie, Manitoba F5 Tornado