Update: Mackenzie Low Brings Blizzard to Southern Manitoba

A potent Mackenzie Low dropped southeastwards through Saskatchewan yesterday riding along with a frontal wave that increased temperatures here in Winnipeg overnight. Behind this system is—for one of the first times this year—a potent Arctic air mass ready to surge southwards.

Today’s major weather features.

As a result, very strong winds developed in the rear of the cold front, supported through a deep layer as evident by a 120 km/h+ jet just off the surface that was visible on Doppler RADAR earlier this morning. Surface winds reached as high as 80-90 km/h behind the cold front which, combined with plenty of loose snow from our extra fluffy snowfall event the other day and some light falling snow, produced white-out conditions across many parts of Southern Manitoba.

The strong winds will move off to the east-southeast with the low pressure system through the morning and visibilities will improve. However, that bitterly cold Arctic air mass will move in through the day, sending temperatures south to around -26 or -27°C by the end of the afternoon here in Winnipeg. Temperatures will continue to drop to a low near -33°C on Friday morning with wind chill values of -42 to -45.

The cold weather will be short-lived as a mild Pacific air mass will begin building into the region this weekend.

Elsewhere in Weather News: April 12, 2014

Cyclone Ita hit North Queensland last Friday, called one of the worst ever in the region.

Visible satellite image of Cyclone Ita as it hit Far North Queensland
Visible satellite image of Cyclone Ita as it hit Far North Queensland

Cyclone Ita hit North Queensland, Australia as a category 3 storm on Friday into Saturday (local time), bringing strong winds and flooding rain to the region. Wind speeds higher than 120 km/h were reported near the small town of Cookstown, Australia and speeds near 160 km/h were reported at Cape Flattery. In addition, more than 125 mm of rain fell in Cookstown. However, the highest reported rainfall total was 311 mm in Bairds. Cyclone Ita hit the Soloman Islands before impacting Australia, causing 21 deaths there. The number of deaths, were there any, from Ita in Australia is not presently known. Luckily, the part of North Queensland hit by Ita is sparsely populated, helping to minimize the impact of the storm.

Cyclones are a common phenomenon in the waters surrounding Australia. Also called willy-willies by locals, cyclones are the same as hurricanes, except that they occur in the Pacific and Indian Oceans, rather than the Atlantic Ocean. The main requirements for cyclone formation are surface water temperatures of at least 27 degrees Celsius and weak vertical wind shear (the absence of a jet stream overhead). These conditions are most often met in the tropics, though cyclones and hurricanes have been known to impact areas at higher latitudes late in the summer and early in the fall.