A Break From The Cold

A break from the bitter cold snap that we’ve been under the influence of over the past week is on it’s way this weekend.

850mb Temperatures valid Saturday Morning

850mb temperatures on Saturday morning from the GEMGLB model. Near–0°C or above temperatures are forecast to push across Southern Manitoba aloft, bringing much warmer weather to the region.

Behind yesterday’s Alberta clipper system, a zonal flow[1] is pushing into the Prairies and breaking down the entrenched northwesterly flow that has been in place over the past week bringing us multiple nights with overnight lows in the mid-minus 30’s and many daytime highs barely climbing over –25°C. The milder Pacific air contained in the more zonal flow will begin to work it’s way eastwards across Alberta and Saskatchewan today, bringing daytime highs closer to –7 or –8°C instead of –20°C.

Friday

Friday

Sunny
-20°C / -29°C

For us in Winnipeg & across the Red River Valley, we’ll face one more day with quite chilly temperatures. Under mainly sunny skies, temperatures will climb to about –20°C with light winds. Temperatures will drop quite a bit tonight as another arctic ridge passes over us; our last cold night before the warmer air pushes in will see us with temperatures bottoming out near –29°C.

Saturday & Sunday

Saturday

Mix of sun and cloud. Increasing cloudiness overnight.
-12°C / -13°C

We’ll see a mix of sun and cloud on Saturday as the milder Pacific air finally pushes in. Temperatures will climb quite quickly through the late morning and early afternoon from our overnight low all the way up to –12°C by the evening hours. By the evening there may be a few light flurries over the southeast portion of the Province (Whiteshell & Sprague), but through the Red River Valley there’s no significant chance of any snow. Temperatures will remain fairly steady overnight as more clouds push in.

Sunday

Mainly cloudy. Chance of flurries overnight.
-7°C / -8°C

We’ll see mainly cloudy skies on Sunday as more moisture and lift begin to spread over the province ahead of an approaching shortwave. Temperatures will climb to around –7 or –6°C across Southern Manitoba; the warmest day we’ve had in what seems like quite a long time. Overnight, an increasing chance for light snow will move into the province, starting with southwest Manitoba in the evening hours and slowly spreading eastwards overnight. Temperatures will remain steady, perhaps drop a degree or two, overnight as we remain cloudy with warm air over the region.

Next Week

Next week is looking like we’ll see a return to colder weather. There’s some uncertainty with regards to the strength of Monday’s system; it may be a fairly organized feature that brings close to 10cm over SW portions of the province and 5–10cm over the Red River Valley and areas eastwards, or it may end up being a rather disorganized system that brings just some scattered light flurry activity with only a couple cm for most places. With either scenario, it still looks like Monday will be the warmest day yet in our little break from the cold. Unfortunately, it looks that once this system passes, Arctic air will once again push back over the Eastern Prairies and establish itself; locking us back into a sunny, but very cold, weather pattern with daytime highs back near –20°C.


  1. A zonal flow, with respect to meteorology, is one that travels more west-east than it does north-south. By contrast, a meridional flow is one that has a larger north-south component than west-east.  ↩

Bitter Cold Continues

The bitter cold entrenched over Southern Manitoba will persist a few more days as another Arctic Ridge slides through the province.

850mb Temperatures valid Wednesday Morning

850mb temperatures valid this morning from the GEM-REG. A pool of bitterly cold Arctic air over the province will restrict daytime highs to the mid-minus-twenties today.

We’ll see an extremely cold day today with plenty of sunshine and a high only around –25°C. This is some 12–13°C below our normal daytime high for this time of year of –12°C. Temperatures will drop below –30°C tonight for a 3rd night in a row.

Light Snow on Thursday

Temperatures will continue to be cold on Thursday with a high near –21°C as a weak disturbance slides across the province in the northwesterly flow aloft. This will spread an area of snow across southwestern portions of the province early in the morning and into the Red River Valley near midday. With temperatures so low SLR values will likely be quite high, somewhere in the range of 20:1 to 25:1. This very high “fluffy factor” will help produce snowfall accumulations of 2–4cm by Thursday evening. Temperatures will climb to around –20°C on Thursday, aided by the cloud cover that will push in.

On Friday sunshine will return as we face another cold day with highs below –20°C. Fortunately, it appears that warmer air will finally be pushing into the region by Friday night. Temperatures look to drop only a few degrees from our daytime high as we then see much warmer weather on Saturday and Sunday as highs climb back towards the –12 or –13°C mark. It looks like we’ll see a mix of sun and cloud through the weekend, with a chance for another couple of cm of snow on Sunday.

An Arctic Blast

This week will feature the coldest weather so far this winter, which is probably about all you need to know.

850mb temperatures on Monday morning

As we come off Monday morning’s very cold low temperatures, daytime highs won’t be able to get very warm, with values in the mid minus twenties expected. When you factor in the wind chill it will feel more like the low minus forties on Monday morning and the mid minus thirties on Monday afternoon. As we move into Monday night temperatures are expected to plummet once again. Models have had significant difficulties figuring out what will happen by Tuesday morning. Models have shown lows as cold as -47C on Tuesday morning (obviously an erroneous value), or as warm as -28C. It seems probable that we’ll end up somewhere between those two extremes, with lows in the mid minus thirties most likely. It shouldn’t be very windy at all on Tuesday morning, so at least we won’t have a big wind chill to contend with as well. It looks like we’ll “warm” up a bit on Tuesday, with daytime highs in the low minus twenties expected.

We shouldn’t see extreme overnight lows again on Wednesday morning since a weak passing weather system will prevent temperatures from bottoming out. However, another arctic front is forecast to pass through Southern Manitoba during the day on Wednesday, setting up more very cold weather for late week.

Unfortunately, there are no indications to suggest that we’ll see a warm-up any time soon. That means we may be stuck with cold to very cold weather for the rest of January.

Elsewhere in Weather News: January 20th, 2013

Intense Heat Wave Continues in Australia

A significant heat wave has remained in place for most of Australia’s southern half, this past week. The large ridge of high pressure has kept about 70-80% of Australia under extreme high temperatures (over 40°C) and in turn has created dangerous conditions in which bushfires can occur. Total burn bans were in place for a few communities in the southern half of Australia and firefighters are on high alert. As of Friday there were 142 bushfires burning in New South Wales alone and 29 of them were 0% contained.

Temperature map

Map of Australia’s extreme temperatures on January 12th, 2013. (Source: Australia’s BOM)

Residents of Tasmania have been experiencing similar weather conditions this New Year, contributing to a massive brushfire that had been raging through a large area of its south-eastern peninsula two weeks ago. Here, 1,000 people had to be rescued by boat from their homes. The damage in that area has not yet been tallied, but at least 20 houses, including a school, has burned down to the ground and at least one person is confirmed dead.

On Friday, January 4th, the village of Wudinna, located on Australia’s southern coast, reached extreme temperatures of 48.2°C, and various other cities broke their daily temperature records as well. Adelaide recorded all-time January high temperatures on the same day as the mercury rose to 44.1°C. Even more impressively, on January 12th Moomba (South Australia) managed to reach a temperature of 49.6°C – Australia’s hottest temperature in 15 years. The average temperature for Southern Australia ranges between 25°C and 35°C in January, and a little cooler for areas along the coast. This past week, Australia’s Bureau of Meteorology even had to go to the extreme by changing the temperature scale on their maps because temperatures constantly exceeded the scale during this intense heat wave.

Trough

Potential through coming through which would help cool down the temperatures late next week. Also to note a possible tropical disturbance on Australia’s north side. (Source: Australia’s BOM)

Although it is not uncommon to see heat waves affecting specific areas of Australia, to see between 70 and 80% of Australia experiencing a significant heat wave such as this one, is not a common sight. Significant heat will persist into next week before a large trough moves into the region and brings an end to the sweltering heat by next Friday. Interestingly enough, models are also showing a tropical cyclone forming off the Australia’s North Coast around the same time that the heat is predicted to come to an end.