Tornadoes, hail, heavy rain pound southern Manitoba
CBC News | Posted: June 25, 2015 12:38 PM | Last Updated: June 25, 2015
There were also several reports of funnel clouds associated with the thunderstorms
Environment Canada confirms two tornadoes touched down in southern Manitoba on Wednesday — both near Manitou.
There were no reports of damage and both were rated as EF0 on the Enhanced Fujita Scale used in Canada
A possible third tornado was reported near Treherne, about 60 kilometres north of Manitou, but that has not been confirmed by Environment Canada.
There were also several reports of funnel clouds in Pilot Mound, La Riviere, Manitou, Winkler and Altona. If a funnel cloud touches the ground, it becomes a tornado.
Manitou tornadoes
The first Manitou tornado touched down at 3:55 p.m. three kilometres east of Manitou, according to Environment Canada.
A dust cloud was seen at the base of the funnel, confirming it touched ground.
"This was considered a land spout tornado that was generated by weak rotation under rapidly growing clouds or weak thunderstorms," Environment Canada stated.
Landspout tornadoes do not usually cause significant damage but can still be dangerous — toppling trees, damaging roofs, or toss debris a short distance.
The second tornado was reported at about 4:25 p.m. approximately seven kilometres northwest of Manitou.
Again, a dust cloud was seen at the base of the funnel, which Environment Canada has also labeled as a land spout tornado.
Treherne tornado?
Environment Canada received reports of a tornado about 10 km south of Treherne but there is not enough evidence to confirm it yet, the agency said.
Meteorologists are continuing to investigate it, however.
Environment Canada meteorologists are seeking pictures of any of the tornadoes or damage they may have caused. Anyone with information about them is asked to call 1-800-239-0484, send an email to storm@ec.gc.ca, or tweet to #mbstorm.
Rain amounts
Heavy rain was reported in many areas of southern Manitoba due to the thunderstorms that rolled through the province.
- Oak Lake towards Alexander — 50-60 millimetres.
- Near Glenboro — as much as 100 mm.
- West of Hallboro — 70-85 mm.
- Manitou — 100 mm
In northeast Winnipeg, a storm produced nickel-to-quarter-sized hail before becoming a heavy rain. Rainfall totals varied highly across the city, but the hardest hit areas were the downtown core northeastwards into Transcona, said Environment Canada.
Within this area, confirmed rainfall amounts vary from 10 mm up to around 40 mm. And there was a narrow swath that received as much as 75 mm.
How do we rate tornadoes?
On April 1, 2013, Environment Canada adopted the Enhanced Fujita Scale — or EF-Scale — to measure the strength of a tornado (it had been in use in the U.S. since February 2007).
It's an improved version of the original Fujita Scale that was devised in 1971 by a pioneer in tornado research at the University of Chicago, Tetsuya (Ted) Fujita.
The new EF-Scale estimates three-second-gust wind speed inside a tornado based on the damage that's observed by examining a large number of indicators, ranging from residential housing to office towers to trees, as well as ground markings and meteorological data. The EF-Scale damage ratings are backwards-compatible with the original F-Scale, but the associated wind speeds have undergone major changes.
The EF-Scale ranges from 0, for a tornado that pushes over shallow-rooted trees and causes some damage to chimneys and signs, to 5, when houses are lifted off their foundations, vehicles are thrown 100 metres or more, and trees are uprooted and carried long distances.
| Intensity | Wind Speed | Damage |
| EF0 | 104-137 km/h | Damage to trees, shingles, antennas and windows |
| EF1 | 104-137 km/h | Trees uprooted, cars overturned. |
| EF2 | 104-137 km/h | Roofs blown off homes, sheds destroyed, mobile homes flipped. |
| EF3 | 219-266 km/h | Walls, roofs destroyed, metal buildings collapsed, forests destroyed. |
| EF4 | 267-322 km/h | Well-built homes mostly destroyed, heavy objects thrown long distances. |
| EF5 | 323 km/h or more | Homes destroyed and/or blown great distances, roofs blown off larger structures, which are otherwise heavily damaged. |