Thursday, November 06, 2014

Mild pattern coming to an end.. colder weather on the way this weekend through next week

6-10 day CPC outlook for next week shows
massive outbreak of below normal temps
over central and eastern NA

The extended period of mild weather we've been enjoying across southern Manitoba over the past month will be coming to an end this weekend as a large scale change in the upper weather pattern drives cold Arctic air southward over the next week or two. The change in the weather pattern will be heralded by a storm system tracking across Manitoba tonight into Friday that will bring some rain across the south along with increasing winds and one final shot of milder temperatures. As the system pushes east into Ontario, it will drag a cold front across southern Manitoba Friday afternoon with winds shifting into the northwest. These winds will bring in colder air Friday night into the weekend with temperatures remaining below freezing. Fortunately, it looks like the cold weather won't be accompanied by a lot of snow, although there will likely be bands of lake effect snow off the Manitoba lakes at times, as well as occasional flurries over southern MB. The cold weather pattern is expected  to persist through next week with generally dry conditions and perhaps an occasional dusting of snow with weak impulses passing through from time to time. Currently, no major storm systems are forecast to impact southern Manitoba over the next week which would minimize the chances of a significant snowfall. However, with this prolonged change to cold weather, it will only be a matter of time before a system brings the first widespread snows across southern Manitoba. Until then, bundle up!   

9 comments:

  1. Looks like this cold weather is going to stick around for quite some time with the blocking pattern setting up!!

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  2. Looks like Winnipeg and the Red River Valley is socked in with the low cloud and flurries today, while either side is seeing sunny skies!!

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  3. Anyway of finding out what the coldest recorded temperature, without snow on the ground, in Winnipeg is?

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    1. Consistent snow depth records only go back to 1955 unfortunately.

      Going back to 1955, the coldest we've gotten with 0 cm snow depth was November 24, 1993 with a low of -21.2°C. If we include a trace cm snow depth, then the coldest we've gotten was -33.3°C on December 1, 1976. So, in the coldest of cold snaps, we can still get quite cold despite little snow cover.

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    2. Thanks for the info JJ.. interesting bit of trivia. Didn't realize we could get below -20C without snow cover! I would have thought -15 to -18c would be the minimum.

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  4. Winnipeg seeing some heavier flurries this evening and already starting to get a dusting in the lawn.

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    1. 1 cm at my place from those flurries last evening which actually were lake effect off Lake Winnipeg as winds shifted into the NNE. So we had lake effect flurries off Lake Manitoba in the morning with a NW wind, then lake effect off Lake Winnipeg in the evening with a NNE wind.

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    2. So will tonight's snow be lake effect also, or is it a actual system snow??

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    3. Anonymous.. Tonight's snow looks like some minor system snow that will be enhanced by lake effect, with upper support generating some locally heavier intensities with lake effect at times. The winds are forecast to be straight northerly off lake Winnipeg and Manitoba which will put the north-south oriented streamers directly south of the lakes. Off Lake Winnipeg, the main band would set up just east of Winnipeg through a Selkirk-Oakbank-Ile De Chenes line, although the eastern sections of Winnipeg could certainly see some decent snow tonight into Wednesday morning. Another lake effect band will set up off Lake Manitoba through Portage LP to Morden area.

      Snowfall amounts will be tough to predict depending on where these bands set up, and how long they lock in a certain location. Overall, I think a good 2-5 cm for most areas of the city possible tonight into Tuesday morning, but 10 cm or more possible under those heavier lake effect bands especially over the east end of the city. RDPS model is actually showing potential for 15-25 cm of fluffy snow through the Selkirk area tonight into Tuesday, but not a lot of confidence the band will set up that strong. Something to keep in mind though, especially for the morning commute Wednesday.

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