Tuesday, January 31, 2012

January 2012 3rd warmest January on record in Winnipeg..

January 2012 will go down in the record books as Winnipeg's 3rd warmest January since records began in 1873. The month finished with a monthly mean temperature of -10.8C, 7C above normal, and the mildest January behind 2006 (-7.4C) and 1944 (-10.6C) The month began exceptionally mild with temperatures some 15C above normal over the first 10 days of the month. The only cold weather of the month was between the 17th and 20th when temperatures dropped into the -20s. Other than that, temperatures were above normal nearly every day of the month. The mild weather continued the trend of December which was also well above normal (6C above normal) and ranked as the 9th mildest December on record in Winnipeg. January 2012 marks Winnipeg's 7th consecutive month that has averaged above normal, going back to July 2011.

Top 5 warmest Januarys in Winnipeg (since 1873)

1. 2006 ......... -7.4C
2. 1944 ......... -10.6C
3. 2012 ......... -10.8C
4. 1942 .......... -11.4C
5. 1992 .......... -11.5C

Normal .......... -17.8C (1971-2000 30 year average)

A look at the temperature anomaly map for January (left) shows how the central Prairies experienced the most abnormal warmth during this past month. The persistent warmth this winter can be attributed to a stronger than normal Arctic jet stream which has been generally stuck in a position over the Arctic. This has effectively blocked intrusions of Arctic airmasses southward over the Prairies, while allowing frequent invasions of mild Pacific air from the west. This is a result of a persistently positive phase of the Arctic Oscillation, a climatic pattern affecting the flow of air across the northern latitudes of the globe. This northern oscillation has more than offset the climatic impacts of La Nina, which normally would bring colder and snowier winters to western Canada and the Prairies... an outlook many were predicting this winter. The northern extent of the jet stream has also deflected storms further north, resulting in a notable lack of snow over the prairies, and the 3rd least snowy January on record in the US. Click here for a good summary by Jeff Masters on the impacts of the Arctic oscillation on this year's winter.

8 comments:

  1. How many months in a row have we had above normal temperatures now?

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  2. Rob!
    Some very thick fog has moved into the City. Thick as in I cannot see across the street. Careful out there!!

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  3. The visibility just south of downtown Winnipeg is basically zero.

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  4. Yes, very thick fog has developed over south and west parts of the city (webcams show downtown and north Winnipeg are still pretty clear for now) Zero visibility at the airport. Fog will likely persist through the night into the morning.

    Brad.. January is our 7th straight month above normal, going back to July last summer. Will February be the 8th?

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  5. Just finnished a shift of snow clearing and we could not find the driveway to the shop. Fog is so thick you can't see anything until you are on top of it. At least the north side of the city near the perimeter.

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  6. I continue to be amazed by the lack of snowcover over central and western North Dakota. Absolutely bare ground along and west of a Minot-Jamestown line with temperatures today in the +7-10C range there. Interesting note from NWS Bismarck indicating they've only had 5.9" (15 cm) of total snow so far this winter, currently on track to be the least snowy winter on record for them. If this keeps up, they'll likely be setting all time February high temperature records as the stronger sun and warmer airmasses start spreading across the plains.

    NWS GFK reports January 2012 was the 4th warmest Jan on record for them, as well as Fargo.

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  7. Is it true, only one of those 4 years, 1992, continued above normal for February. Perhaps the Pinatubo effect.

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  8. Fog on the west perimeter last night was the thickest I've ever seen. I could only see at most a few feet in front of my car. Made for very dangerous driving conditions. Cleared quite rapidly past McPhillips St. and further east.

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