Elsewhere in Weather News: July 20th, 2013

Severe Weather Outbreak in Southern Ontario; Numerous Warnings Issued Friday

On Friday, severe weather rolled across much of southern Ontario, southern Quebec and nearby states such as Michigan and New York. Severe weather was imminent in the region as a strong squall line of storms formed with some bowing segments in the morning and continued into a great thunderstorm environment as the afternoon wore on. CAPE values were quite high, shear sufficient and for any storms that remained discrete, a decent tornado potential was there before getting absorbed into the squall line. This prompted a plethora of warnings to be issued, including numerous tornado warnings throughout the day.

Wind damage was the biggest concern on Friday though, numerous reports of wind gusts exceeding 100km/h and even one report as high as 119km/h in Waterloo Ont., were reported. In turn, significant damage was reported across southern Ontario; mature trees knocked down, trees falling on homes and winds flattening crops. As of Friday night 550,000 people were still without power in Quebec and Ontario due to winds knocking down power lines and trees falling on lines. Storm survey teams are expected to head out to various spots across southern Ontario tomorrow to determine if damage was caused by straight-line winds or a tornado touching down. Two unconfirmed funnel clouds had been reported around the towns of Bradford and Barrie, Ontario. Unfortunately one person has died and ten more have been injured because of falling tree limbs; this is a reminder to people that even though a tornado might not be imminent, it’s better to take cover as a storm approaches.

Downed tree

Large trees downed in Toronto by strong winds produced in Friday’s storms. (Source: City News)

The cold front behind this system will put end to Ontario’s heatwave. Many cities in southern Ontario, including Toronto, had reached “official” heatwave status by reaching 32°C three days in a row. This combined with high humidity values made for excessive heat, therefore it’s likely that most residents will welcome the cooler and drier air on Sunday.

Elsewhere in Weather News: April 20th, 2013

Major Trough Moves through US

A trough of low pressure moving across a large swath of continental United States this week has been the cause for severe flash flooding, much wind damage, and a few tornadoes including Canada’s first of the year.

The first severe weather day occurred on Wednesday, April 17th, when a moderate risk was issued by the SPC for most of Oklahoma, parts of south-west Kansas and Missouri. Over 150 chasers (reporting) were scattered throughout Oklahoma, and at one time over 50 chasers could be seen on the same supercell! Severe thunderstorms fired along the warm front and further along the dryline that extended into Texas in early afternoon. The storms that had the largest tornado potential went up in south-western Oklahoma and moved towards the north-east. These storms along the warm front trailed each other and produced flash flooding in some localities. Also to note is that a few cities such as Lawton, OK who were lying along the warm front saw not one supercell that day, but three within four hours. One of these also dropped a tornado which caused some damage to an industrial area on the outskirts of the town.

Chasers

Incredible chaser convergence (red dots) in Lawton ahead of a supercell. Just about every single street in Lawton had a chaser on it! (Source: Spotter Network/RadarScope)

On Thursday and Friday the trough continued its push eastward, but it became less of a tornado threat and more of a severe wind and hail event. At one time, thunderstorms stretching from Ontario all the way down to Texas could be seen. A few states such as Illinois, Iowa, Alabama, and Missouri saw extremely heavy rain in a short period of time which was cause for flash flooding concerns. Air rescues took place in Oxford, Alabama to save stranded motorists caught in their partly submerged cars. Canada’s first tornado of 2013 was also recorded on Thursday, rated as an EF 1 it touched down near Melanchton, Ontario.

Tornado damage

Damage of a barn in Southern Ontario from the EF 1 tornado. (Source: Steve Murphy EMC via Caledon Enterprise)

The cooler weather is not expected to last this weekend as return flow sets up and southerly winds kick in for most of the Plains and Midwest. Later next week it appears as though yet another high pressure will slide down the Rockies, in turn bringing more unseasonably cold air to the Central United States.