Tornadoes, hail, heavy rain pound southern Manitoba

Environment Canada confirms two tornadoes touched down in southern Manitoba on Wednesdayboth near Manitou.

There were no reports of damage and bothwere rated asEF0 on the Enhanced Fujita Scaleused in Canada

• FAQ: Tornadoes, what they are and how they form
• Tornado touching down in Manitou caught on video

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, LaRiviere, Manitou, Winkler and Altona.If a funnel cloud touches the ground, it becomes a tornado.

• Funnel cloud spotted northwest of Winnipeg

Manitou tornadoes

The first Manitou tornado touched down at 3:55 p.m. threekilometres east of Manitou, according toEnvironment Canada.

A dust cloud was seen at the base of the funnel, confirming it touched ground.

Landspout tornadoes do not usually cause significant damage but can still be dangerous topplingtrees, damagingroofs, or toss debris a short distance.

The second tornado was reported at about4:25 p.m.approximately sevenkilometresnorthwest of Manitou.

Again, adust cloud was seen at the base of the funnel, which Environment Canada has also labeled asa land spout tornado.

Treherne tornado?

Environment Canada received reports of atornado about10 km south of Treherne but there is not enough evidence to confirm ityet, the agency said.

Meteorologists are continuingto 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 tocall 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 Alexander50-60 millimetres.
• Near Glenboro as muchas100 mm.
• West ofHallboro70-85 mm.
• Manitou100 mm

In northeastWinnipeg, astorm 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 receivedas much as 75 mm.

How do we rate tornadoes?

On April 1, 2013, Environment Canada adopted the Enhanced Fujita Scale or EF-Scaleto measure the strength of a tornado (it had been in use in the U.S. since February 2007).

It'san improved version of the original Fujita Scale that wasdevised in 1971 by a pioneer in tornado research at the University of Chicago, Tetsuya (Ted) Fujita.

The new EF-Scaleestimates three-second-gust wind speed inside a tornado based on the damage that's observed by examininga 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, butthe 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.