Saturday 22 March 2014

Merciless Winter Continues

    And we thought March last year was cold... Turns out this March will very likely finish colder than last year's. This winter has been relentless with now 4 consecutive months averaging over 3 degrees colder than normal; 3 of which averaging over 5 degrees colder than normal.

     In fact, depending on if warmer weather does materialize next weekend, this December to March period could potentially end up as the coldest in 116 years, since the winter of 1898-1899. It is remarkable that we are currently seeing conditions comparable to the frigid late 1800's when winters like this were common. The finalized stat will come in the March summary at the end of the month.

     Another night in the mid -20's is expected tonight unfortunately. The cold conditions are expected to continue through much of the work week next week. The signs beyond that are unclear at this time.

    Be sure to vote in the latest poll: when do you think the winter snow pack will disappear in Winnipeg? Answer will be determined using my weather data here in south St Vital. The top 5 latest dates for this to occur are below.... notice that last year featured the 3rd latest. Tragically, this is after the third earliest loss of winter snow pack in 2012 when it disappeared by March 14.

Table: Top 5 latest dates for winter snow pack to disappear (reach 0 cm) since 1955


Rank
Date winter snow pack disappeared (reached 0 cm)
Year
1
May 3
2
May 1
3
April 28
4
April 26
5
April 25

24 comments:

  1. JJ, why was this winter which is still ongoing so cold?

    Thanks, Anon

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    Replies
    1. Basically, the jet stream has been very consistent this winter with a trough over central and eastern North America and a ridge over the east Pacific and western North America. Why the jet stream has been so consistent is hard to pinpoint on a single factor and difficult to say because it's position can depend on so many factors, some thousands of kilometres away. Well above normal ocean surface temperatures in the northeast Pacific this winter however may have encouraged the consistency of the west coast ridge this winter, which may have been one factor.

      Here's a video if you're interested showing the extremes seen this winter in North America: https://www.youtube.com/watch?v=XZGsdnYqbjk#t=362... Although they do talk about a negative AO is this video, I'm not really sure that would explain the cold winter because in reality, the AO was strongly positive in December and is currently positive this month.

      I'm not an expert in this, so if anyone has anything else to share, feel free to do so!

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  2. Only expecting a high around -11°C to -10°C today with perfectly sunny skies. Tomorrow will be cloudier, especially in the first half of the day, with chance of some flurries associated with another arctic front. This will usher in a boost of arctic air again with lows dipping into the -20's again tomorrow night. Another cold day for Tuesday.

    Next system to watch will be for Wednesday when a few cm of snow will be possible.

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  3. Yikes! Low at Winnipeg airport this morning was -28.3°C! That's the 4th coldest low on March 23 since 1872:
    Coldest lows on March 23 since 1872:
    1. -32.2°C (1974)
    2. -29.4°C (1899 and 1965)
    4. -28.3°C (2014)
    5. -27.8°C (1877)

    ReplyDelete
    Replies
    1. Low ended up being -28.4°C, not that that makes a big difference..

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  4. JJ, will that system for Wednesday usher in yet another cold arctic airmass as well?

    Thanks, Anon

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    Replies
    1. Looks like a weak push of cold air behind it, but it looks brief and not very significant at this time.

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  5. JJ, does Wednesday's system bring a threat for a large snowfall here or just a nuisance minor type of snowfall?

    Thanks, anon

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    Replies
    1. Haven't looked much into it yet, but so far it looks like 2-5 cm. However, there is some discrepancies in model land so that may change in the next few days. There seems to be good consensus at this point that there will be a Colorado Low developing to our south around that time (which consensus is that it will stay to our south!) which complicates things.

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  6. It's now been 128 days since I've seen/measured any rain... Incredible.

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  7. Unfortunately, still quite uncertain about tomorrow's snow. Looks like we may end up right on the edge of things again. As a result, model forecasts vary anywhere from 4-7 cm to little to nothing. Just have to wait and see what the next runs trend towards...

    Looks like we will indeed get a warmup this coming weekend, but it looks very brief, lasting only a day or two. Colder air makes an unwelcomed return by Monday. Hard to say how long the below normal temperatures will last.

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    Replies
    1. It just keeps getting more and more difficult to get above normal temperatures now because normal highs are rising so quickly. Normal highs reach +5°C already by this weekend (1981-2010 normals)

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  8. JJ, I've heard that there are hints of a major snowstorm south of the border into the Dakotas late Sunday into Monday.

    Will this storm affect us here in Southern Manitoba as well?

    Thanks, Anon

    ReplyDelete
    Replies
    1. Yeah, there is the potential for a more major system around that timeframe. So far, looks likely that the storm will stay to our south, but will have to watch for any northward trends.

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  9. Well, although I am still skeptical about this somewhat, there continues to be some hints that a pattern change could take place within the next 2 weeks as the Arctic vortex collapses in which will finally allow Spring if you wish to show up here and give us that much anticipated warmup that we are looking for and wanting so badly. But again this is not set in stone yet and there should only be cautious optimism at this point.

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    Replies
    1. I've never been so cautiously optimistic.... Warm weather seems like fantasy at this point.

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  10. Tragically, the average date for the winter snow pack to reach just a trace cm (almost disappear) is tomorrow (1981-2010 normal).

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    1. Using 4negatives BAD News #1 2 and 3 and a good news which is actually bad has made this fore cast A positive or am I reading this wrong?
      http://www.crh.noaa.gov/news/display_cmsstory.php?wfo=fgf&storyid=101288&source=0

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    2. Actually this is the NWS spring outlook which referred me to the site. Generally agrees with you and perhaps says alittle more about the El Nino on the horizon.

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    3. http://www.crh.noaa.gov/news/display_cmsstory.php?wfo=fgf&storyid=101294&source=0

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    4. Wouldn't surprise me if spring continued to see a general below normal trend as that is what has been shown historically after cold winters like the one we've had. Haven't had the opportunity to gather any stat probabilities yet. But we'll see, of course we all know that things can change quite drastically around here.

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  11. Looks likely that the bulk of the snow will miss us today. Unfortunately, we haven't quite gotten rid of the cold, but at least we've sort of gotten rid of the snowstorms. Still a close call though, so don't be surprised to see a cm or two late in the day if things end up a tad further north.

    Another chance for snow on Saturday however with a few cm possible.

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  12. Managed to gather a few stats to see how historically, April would be like after a comparable March. First, it looks likely that this March will be in the top 25 coldest.

    -Of the 26 coldest Marches, only 7 were followed by an April that was warmer than the 1872-2013 April average mean of 3.5°C. Below is a list of how the following April, of those 26 coldest Marches, ranked compared to the 1872-2013 April average mean of 3.5°C:

    3 (12%) were at least 3°C ABOVE the average
    7 (27%) were ABOVE the average
    19 (73%) were BELOW the average
    10 (38%) were at least 3°C BELOW the average

    Only 5 (19%) were at or warmer than today's average April mean of 4.5°C (1981-2010 normal).

    Therefore, historically speaking, there is a high chance that April will be cold after a March as cold as this year's. However, dramatic turnarounds have occurred in the past... we'll see what April has to bring this year.

    ReplyDelete
    Replies
    1. Actually, I've found an even stronger correlation. This December to March period is on track to be a top 10 to 12 coldest on record.

      Now get this! Turns out that of the 20 coldest December to March periods, NONE were followed by an April that was warmer than the 1872-2013 average of 3.5°C. 55% were followed by an April that was over 3°C colder than that average.

      I think it will be hard to beat that trend!

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