Saturday, 5 January 2013

#4 - Top Ten Weather Events of 2012 in the Winnipeg Area

Early Winter Wallop

     An unseasonably intense snow storm on Oct 4 and 5 put an abrupt end to summer-like weather. Less than a week earlier we were basking in near record heat. On September 29, it was nearly 30°C in Winnipeg, and it was in the high twenties throughout southern Manitoba. And on October 2, just two days before the winter wallop, it was in the low to mid twenties.

Plowing in early October! Pic by
     The system formed over South Dakota on Oct 3 and tracked northeastwards into northwestern Ontario on the 4th, bringing a large swath of precipitation over southeastern Manitoba. Precipitation actually began as rain on Oct 3 and early on Oct 4, and a lot of it fell. As much as 30 mm of rainfall fell south and east of Winnipeg, while 5 to 10 mm fell in Winnipeg. Rain switched over to a very wet and heavy snowfall early in the morning on Oct 4, and was heaviest southeast and east of the city up to the Ontario Border. A general 10 to 20 cm of snowfall fell across southeastern Manitoba, northwestern Ontario and northwestern Minnesota by Oct 5. Heaviest hit areas east and southeast of Steinbach received at least 30 cm! Truely remarkable for that time of year. Here are all the snowfall totals (in cm) I could gather in the form of a map:

Map thanks to google maps
Winnipeg, pic by Neil Carleton/CBC
     Snowfall also fell over the western RRV near the escarpment however, thanks to upsloping. In addition, more snowfall fell downwind of Lake Manitoba, south of the lake, thanks to lake enhancement. Winnipeg thankfully just missed out on the storm with just a slushy 2 cm which did not even stay on the ground for more than a few hours. Higher totals were very close with as much as 9 cm in Oakbank and 15 cm in Garson, just east of the city. Visible satellite image showing snow cover here. Video of snowfall in Pinawa here, and in Winnipeg here.

     Strong winds gusting up to 70 km/h accompanied the snowfall, only worsening visibility. RCMP had issued travel advisories east of Winnipeg since many vehicles ended up in the ditch along the Trans-Canada due to icy, snow-covered highways. Some parts of the Trans-Canada were down to one lane.

     Steinbach Towing was exceptionally busy as a result. At one point on Oct 4, they had 26 calls on the go all at the same time. They were forced to prioritize drivers, starting with those who were stranded. They also ended up working through the night.

Drooping power lines; pic by Lothar Dueck, sent to CBC
     Perhaps the biggest setback with this storm however was power outages. Wet snow and ice accumulating on hydro lines (with as much as 3 inches in spots) combined with strong winds snapped hydro poles and hydro towers all across southeastern Manitoba. On top of that, in some areas the heavy wet snow and strong winds collapsed trees, which some still had leaves, also bringing down some power lines. More than 6,000 were without power in southeastern Manitoba, along with more than 4,000 in northwestern Ontario and 1,300 homes in Winnipeg's Transcona neighbourhood. Transcona's outage was brief, but that was not the case for areas east and southeast of the city. Power outages lasted several days due to the amount of hydro poles that were down, as well as poor road conditions which made it difficult for hydro crews to get to the affected areas. This was not good timing considering many residents were still without power for the Thanksgiving weekend (Oct 6 to 8). Beausejour and the RM of Stuartburn had both issued states of emergency due to the outages. About a dozen homes near Lonesand were without power until mid week the following week.

     In total, at least 250 hydro poles had to be replaced, costing Manitoba Hydro at least $800,000. Crews worked full 16-hour days, and could only work during the day.

     Intermittent telephone and wireless service outages were felt as well due to power interruptions. However, MTS did the best they could to maintain the services with backup generators and battery power. Hospitals and personal-care homes also used alternate power sources, avoiding the need for evacuations.

     However, the precipitation was much welcomed by firefighters who had been battling tough fires before the snowfall. Firefighting efforts were completely halted and fires appeared to be mainly out.

Vita Oct 4, What a difference a day makes! Pic by Jim Swidersky/CBC

Flooded Gimli streets; pic by Ken Krebs, sent to TWN

     In Gimli, strong winds with the system pushed water from Lake Winnipeg onto streets. Clogged sewer drains kept the water on the streets. Crews had to pump the water back into the lake and clear the clogged drains of leaves and sand. No homes were damaged.

     Snowfall this early is rare in southern Manitoba, but does occur from time to time, especially over the higher elevations of western Manitoba. In fact, snow has fallen in these higher elevations as early as September 12. On Sep 12-13, 1903, 10-30 cm of snow fell in western Manitoba near the Saskatchewan border. In October 1959, 3 major snowstorms dumped over 1 metre of snowfall over southwestern Manitoba, making it the snowiest month ever in Brandon. On Oct 7-8, 1985, 10-15 cm fell over Winnipeg with higher amounts in other parts of the RRV. And more recently, on Oct 5, 2005, 20-45 cm fell over southwestern Manitoba with 5-10 cm in Winnipeg. The earliest accumulation of snowfall in Winnipeg was on September 20, 1945 with 1.5 cm.

Lots of cars in the ditch & trees bending over from the snow.. Pic by

This post contains information, photos or video from the following sources:

NWS Grand Forks
Rob's Blog
Environment Canada Weatheroffice
Google Maps
The Weather Network
CBC Manitoba
Winnipeg Free Press
CTV Winnipeg

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