Tuesday, May 07, 2013

Cooler weather on the way..

After 2 days of summerlike temperatures in the mid 20s, things will be cooling off noticeably Wednesday as a cold front pushes through southern Manitoba, with brisk northerly winds ushering in temperatures some 10-15C cooler than the past couple of days.  The cold front will be pushing through Winnipeg after midnight tonight, with northerly winds increasing to 30 gusting 50 km/h behind the front. Temperatures Wednesday will be struggling to get much above 10C, which will feel even cooler with the wind, with below normal temperatures lingering into Thursday. Friday will see a bit of moderation as we get back into a southerly flow of milder air, however another cold front will be pushing through Friday evening ushering in even cooler air for the start of the weekend.  Warmer weather with temperatures back in the 20s is expected by Monday over southern Manitoba.


  1. Frontal passage at YWG airport around 1145 pm with winds shifting to the north and increasing to 20 gusting 27 knots according to live RVR data (http://atm.navcanada.ca/atm/iwv/CYWG)

  2. 34.6C in Ashcroft, BC yesterday!
    Warmest temperature recorded this year in Canada.

  3. Gusty NNE wind coming in off ice covered Lake Winnipeg will keep things pretty chilly today in Winnipeg. I don't see us getting much above 10C this afternoon even with sunshine moving in. Definitely a much cooler day out there..

    Note also that most guidance is showing a chance of some showers Friday with another cold front moving through. Current forecast for Friday doesn't reflect this precip chance.

    Nice warmup for Monday with temps back in the 20s. Current forecast of 28C may be a bit optimistic, but mid 20s look possible.

  4. There's the mostly cloudy observations again... when there's barely a cloud in sight.

    I've also noticed that, if you thought the climate data is all messed up here, it's actually worse in Calgary. For a city of a million +, it's pathetic that they have such ridiculous data quality. Ex: 21 cm of snow in January melted down to 2 mm liquid? On top of that, they have so much missing data you'd might as well say Calgary has NO precipitation data at all right now and hasn't since last summer.

    The big cities should have good data in my opinion; if you need to reduce things to save money, get rid of some of the data for smaller towns. A city of a million + with no precip data is very irresponsable.

  5. >>Anonymous said...There's the mostly cloudy observations again... when there's barely a cloud in sight.

    Once again, observers at YWG and YBR calling this nice sunny sky 6/8 broken cirrus, which again is overdone looking out the window and at satellite imagery. At the most, I would be calling this 1/8 cirrus. Not sure why these observers have such a hazy view of the sky.. maybe they should clean their windows!

    As far as climate data quality, I would encourage anyone unhappy with the quality of EC climate data or forecast services to contact EC and state your concerns. Click on my name for contact link..

    I think it's important to provide EC feedback concerning the services they provide, and to highlight any areas that you feel need addressing. It's only with direct feedback from the public that EC can gauge what areas they should be looking to improve.

  6. Interestingly, the observer at Portage (YPG) is calling this 1/8 cirrus, which decodes as "Mainly sunny". The observer at YPG is a DND (Dept of Defense) observer, while the observers at YWG and YBR are NavCanada observers. So evidently, it's cloudy in Brandon and Winnipeg, but sunny in Portage.

  7. Cloudy right now? That takes the cake! If the sprinklers went on outside their building, they'd probably report 'light rainshower'.

    Thanks for the suggestion Rob, I'll think about sending a comment.

  8. If you squint, there is a broken cirrus layer, but the opacity is a trace. WHY, OH WHY does NavCanada not report opacity? And WHY is the amount being coded into the METAR remarks where opacity should be placed? It's wrong.

    Regarding the climate data, as far as I'm concerned there is no such thing anymore in Canada (apart from tree rings, sea-levels, etc.). When the QC program was cut years ago, climate data ceased to exist (not even counting the degradation of the observing program).

    They say they are thinking about getting the station techs to QC the data now instead of having actual QC staff. Wonderful (sarcasm). EC has been informed, but aren't too keen on listening yet.


  9. >>WHY, OH WHY does NavCanada not report opacity? And WHY is the amount being coded into the METAR remarks where opacity should be placed?

    Garth.. I think it's a METAR thing. Opacity is no longer reported with METARs, even in the states. So we longer have the ability to report "thin" cloud layers based on opacity.

  10. Thanks Rob. Then the documentation hasn't been updated. NavCanada's Aviation Weather Services Guide still says the cloud value in the METAR remarks is opacity.


    Portage still reports that value as opacity, not amount:
    METAR CYPG 091800Z 03007KT 360V060 15SM BKN250 11/M06 A3035 RMK CI2

    2/8ths coverage is not BKN, so must be an opacity value. The raw SWOB-ml data also has separate 'amount' and 'opacity' values for Portage (currently 20% opacity, 80% amount).

    So we have a situation where the number after the cloud type is ambiguous, meaning 'amount' at NavCanada stations, but otherwise 'opacity'. Apparently.

  11. Garth..

    You're correct. Looks like cloud cover should be based on opacity not amount. Both values used to be reported, which is no longer the case with METARs.

    But I think you're right in saying that NC observers seem to be confusing cloud opacity with amount.

  12. Rob, regarding the +6c foretasted high for Wpg on Saturday from EC - doesn't it sound extraordinarily cold considering it will be full sunshine?

  13. >> Anonymous said... Rob, regarding the +6c foretasted high for Wpg on Saturday from EC - doesn't it sound extraordinarily cold considering it will be full sunshine?

    Yes it does.. unfortunately, I don't think it'll be much warmer. Very cool day with brisk NW winds tapping a cold airmass from northern MB. We may squeeze out an 7-8c with enough sun, but not much higher. Fortunately, looks like a short cool snap as temps rebound nicely by Monday.

  14. Rob, regarding the potential for thunderstorms on Tuesday I notice that there is a fairly high amount of instability and lift forecast with one of the low pressure systems that will likely slide into our region. What's your opinion on this system & the thunderstorm potential? I'm betting on storms...

  15. Rob,
    take a look at these Monday and Tuesday temps for us!
    GEM-Mon 26.1, Tue 28.7.
    GFS-Mon 23.3, Tue 26.4.
    NAM-Mon 24.3, Tue 23.
    EURO-Mon 16, Tue 22.
    GDPS-Mon 24.8, Tue 28.3
    EC-Mon 25, Tue 27.
    TWN-Mon 25, Tue 27.
    AW-Mon-20, Tue 25.

    Its amazing how low Euros temps are, while GEM has a beautiful 26.1 for monday and 28.7 for tuesday. Another funny thing is that NAM has 16 MM of rain for monday with some rumbles of thunder.

    Personally I would agree with GFS for temps, with some rumbles of thunder although not as extreme as NAM. I mean now that we are in mid may we should get some thunderstorms.
    what are your thoughts on this matter?

  16. Mike (St. James region)9:32 PM, May 11, 2013

    Rob, it seems everytime I post on your comments someone uses my blogger account and links to it. I keep getting hacked, any way you could fix this?

  17. Mike.. re: thunderstorm potential for Tuesday. Models are showing a potential for elevated warm frontal storms over northern ND early Tuesday morning which may spread across the border into southern MB through the morning hours. Whether any cells reach Winnipeg is tough to say at this point, but there could be a few cells around Tuesday morning. Activity and tstorm potential moves east of srn MB in the afternoon.

  18. Mike (St James).. I will try to look into it, but it's not an obvious fix. I just need to be more vigilant in recognizing duplicate accounts. This has happened with other users accounts as well. I don't know who is using other people's accounts to post comments, but please refrain from doing so. You can post anonymously and your comments will still get posted..

  19. Impressive ice flow damage to cottages on the south shore of Dauphin Lake last evening (smaller lake just east of Dauphin). Gusty NW winds up to 80 km/h last evening pushed large pieces of lake ice onshore, up to 30 feet high in places, damaging or destroying at least 20 cottages along the lake.

    Click on my name for CBC story..

  20. @Rob

    Now that's what you call an ice tsunami.