Tranquil December ends with heavy snow

It seems like Mother Nature saved all of her December snow for the very end. A steady snow began in Winnipeg on Saturday the 30th around 3 pm, and continued through the night moderate to heavy at times before ending by 8 am Sunday morning the 31st. By the time it was over, some 25 to 30 cm of snow had fallen in the Winnipeg area.. with 29 cm at my location in Charleswood, and 32 cm at Winnipeg airport. Up until this storm, snow had been virtually absent this month in Winnipeg with some very minor snowfalls during the first half of the month totalling about 4 to 8 cm (7.8 cm at my location) In fact, prior to this snowfall, no snow was recorded at all in the city after the 16th. The snow will be welcome news for snowmobilers and snow enthusiasts who have been frustrated with a very meager snow season so far this year. Average December snowfall in Winnipeg is 20 cm, so this December will end up snowier than average.. a misleading statistic due to this one heavy snowfall at the very end of the month.

EC now calling for mild December..

The latest 30 day outlooks were issued yesterday, and not surprisingly, EC has done a complete 180 in its December outlook. The forecast now calls for above normal temperatures for much of the country, a complete reversal from its below normal outlook issued two weeks ago (see Robs blog entry from Dec 4) This outlook is now consistent with CPC's December outlook from the U.S. which had been calling for above normal temperatures over the Prairies this month, and maintains this outlook in its latest update. And judging by the way the weather pattern has been this past week, and the week ahead.. it appears that the above normal forecast is going to work out.

It appears that EC's 30 day outlooks are heavily influenced by current weather patterns (i.e. persistence). Note that EC's below normal outlook two weeks ago was issued during a period of below normal temperatures across the Prairies. Now that's its mild everywhere, the outlook is above normal. It'll be interesting to see if this correlation holds for January's outlook in two weeks. (30 day outlooks are updated every two weeks)

A little snow Friday.. a little colder for the weekend

That big Pacific storm system that will be crashing into west coast today will track across the Prairies on Friday, albeit in a weaker form, bringing an area of snow across SK and MB. Over southern MB, the snow should spread in from the west during the morning reaching Winnipeg by afternoon. Most of the snow should fall along and north of the Yellowhead Highway through the Riding Mountain and Interlake areas into central MB where 5 to 10 cm is possible. Here in Winnipeg and the Red River valley, snowfall will likely be less.. perhaps 2 to 4 cm through the afternoon hours with even a chance of some mixed precipitation (rain/freezing rain) in some places. Slightly colder temperatures will follow in the wake of this system for the weekend, but temperatures are only expected to drop to "normal" values for this time of year with highs around minus 10. (It'll actually be nice to wash those cars and keep them clean for more than a day!) The colder weather however is not expected to last long as another surge of mild Pacific air is forecast to move over southern MB by the middle of next week.

A mild week ahead..

The above normal temperatures will continue over southern Mb this week as a mild Pacific flow dominates over the Prairies. This will mean daily temperatures near the freezing mark and more of those messy roads and melting snow (stock up on that windshield fluid!) The mild temperatures are nice.. but some of those Winnipeg side roads are becoming a real mess with all that unplowed snow getting pretty thick in spots due to compaction and rutting. A grader pass or two sure would be nice right about now!

By the end of the week, a couple of weather systems tracking through the Prairies threatens to bring some snow to Winnipeg by Thursday and Friday. However at this point, it appears that the bulk of the snow with each of these systems will be mainly north of Winnipeg through the Interlake and central MB areas, with minor amounts over the south. Slightly colder temperatures are expected next weekend in the wake of these systems but at this point, a change to a prolonged period of cold weather is not anticipated. In fact, long range guidance from CPC indicates above normal temperatures over southern MB leading up to Christmas.

Rob's Obs update

Sat Dec 9: Current data from my station will not be updating for awhile today as I go through some PC maintenance. Hopefully, it will be back online this afternoon. In the meantime, you can check out the Pacific Junction (PJ) school weather station in Charleswood for current weather data.

Update: Back online as of 3 pm.

Major warmup by Friday

If you didn't like our recent cold wind chills, there's good news in the forecast. A major push of mild Pacific air is forecast to sweep across the Prairies over the next couple of days, reaching Winnipeg by Friday. Gusty southerly winds will begin to push the cold air out on Thursday, although the brisk winds and departing cold air will still make for one more cold day. Noticably milder conditions will move in on Friday with temperatures possibly approaching the melting point. The mild conditions should continue over the weekend, especially Saturday when temperatures should rise above zero over much of Southern MB.

Dec 2006 Outlook

Quite the opposing views on what kind of December we'll have according to the latest 30 day outlooks from Canada (EC) and the US (CPC). According to EC, temperatures across Manitoba, and much of Canada, are forecast to be below normal this December (top image) In contrast, CPC is forecasting a better than even chance of above normal temperatures this December over the eastern Prairies(bottom image)

Who's right? Maybe neither.. It could end up somewhere in between. Correlations with past weak El Nino years suggest that December and January are generally milder than normal here in Manitoba.. but that's not always the case. So I guess we'll just have to wait and see.. and cross our fingers that the Americans are right!

Snow moving in this evening

An area of light to moderate snow was moving into southern MB from the west, with the leading edge of the main snow band around Portage La Prairie as of 5:30 pm. Brandon picked up a quick 2 cm of snow in the late afternoon as the snow band moved through. The area of snow was moving towards Winnipeg at 50 km/h, and should move into the city from the west by 6:30-7 pm. Visibilities will drop to 1 km or less at times in moderate snow, and gusty southerly winds in the Red River valley could give visibility of 300 m or less at times in snow and blowing snow. The snow should end by midnight but then gusty northwest winds behind this sytem will give locally poor visbilities again in blowing snow especially in open areas. Caution if on the roads tonight..

C-C-Cold morning

Coldest morning of the season so far with a low of -29C at Winnipeg airport, -27c at my site. Temperatures were down to -30 or lower in some places over Southern MB this morning. At least there wasn't much of a wind.. but that will change this afternoon as southerly winds start to pick up. That will produce a noticeable windchill this afternoon into this evening with southerly winds of 30 to 50 km/h combining with temperatures near -18c to produce windchills around the minus 30 mark. Bundle up! Those southerly winds are ahead of a trough of low pressure approaching Southern MB that will bring a couple cm of snow tonight. That could result in some slick driving conditions overnight into Monday morning. (It's those minor snowfalls that really slick up the roads, especially at intersections where stop and go traffic compresses the minor coating of snow into ice.. )