Saturday, October 10, 2009

First snow of the season hits Winnipeg

Only two weeks after summerlike weather, winter made a premature entrance over southern Manitoba with an early season snowfall over parts of the province Friday. Snow began in earnest over the Riding Mountain and central Interlake areas early Friday with 10-20 cm reported from Dauphin to Fisher Branch. By Friday evening, cold northwest winds on the backside of the system created snowsqualls off Lake Manitoba that pushed into Winnipeg, dumping 10 cm of snow in the city between 6 pm and midnight. The snow created many problems on area roadways with numerous accidents including 2 multi-vehicle pileups on the perimeter highway around Winnipeg. Intense snowsqualls also developed off Lake Winnipeg Friday night into Saturday producing 30 to 50 cm of snow north and east of Lac Du Bonnet. Temperatures will remain well below normal through the Thanksgiving weekend with occasional flurries from time to time. Another system moving through the Dakotas threatens more snow over southeast Manitoba on Monday.

37 comments:

  1. Can anyone tell me why Manitoba does not get "snowsquall" warnings like Ontario does!!!

    This morning in the SNOWFALL warning it states that a very intense snowsquall is affecting parts of eastern Manitoba..... so why do they not issue a snowsquall warning???

    ReplyDelete
  2. As of this morning, I noticed that the Woodlands radar is still in "rain mode".

    When is the switch to "snow mode" typically made?

    ReplyDelete
  3. Epic lake effect snowfall off Lake Winnipeg!

    East of Lake Winnipeg snowfall amounts have reported as high as
    40 CM

    Break out the snow shovel!!!

    ReplyDelete
  4. That 40 cm report was from Poplar Bay, just northeast of Lac Du Bonnet. Most of it fell overnight into this morning. Radar showed a solid band extending from the Pine Falls area through Great Falls to Pointe Du Bois all the way to Kenora.
    Even that far away, Kenora reported 10-15 cm of lake effect snow today!

    As for why snowsquall warnings aren't issued in Manitoba, it's mainly a public awareness thing. Snowsqualls are not that common here and people may not understand what is meant by that type of warning. In Ontario, snowsqualls are more common and last well into the winter.. so the general public is more aware of what a snowsquall warning means. I'm sure with some public education and media awareness, EC could issue snowsquall warnings here as well at some point..

    ReplyDelete
  5. Re: Rain mode vs snow mode

    I think Weatheroffice switches the radar display to snow mode by Dec 1st or something like that, but I'm not positive.

    ReplyDelete
  6. Remember my "early peak" theory from the last post...?

    Well the 12Z run of the NAM may have been that early peak. The 18Z run has now shifted the main area of precip with the Monday system farther south. This is exactly what happened last year with a countless number of systems...those systems led to record snowfalls in ND.

    While it is still too soon to tell whether or not the models are final on this southerly solution, I suspect the "early peak" may have struck again!

    ReplyDelete
  7. Good to see NAM keeping it south.. let Dan have some fun!

    ReplyDelete
  8. Anonymous, I'm pretty sure that environment Canada's radar switches to rain mode on April 1st, and back to snow mode by Nov 1st.

    ReplyDelete
  9. If Winnipeg airport get down to
    -10 C tonight will that be a record cold night?????

    ReplyDelete
  10. Record low for tomorrow is -8.9C set in 1874. (complete list of daily record temperatures for Winnipeg are available on my "STATS PAGE", under the temperature anomaly map) For us to get to -10C, we'd have to clear out early this evening and stay clear all night. There's quite a bit of cloud cover over us as well as much of the Prairies, and there's not much wind to flush things out. We've got a lot of low level moisture with the melting snowpack and the cold air over the open lakes, so I'm skeptical about how much clearing there'll be. I'm sure there'll be breaks, but probably not enough to get us down to record low territory. I'm thinking -5 or -6C if we get clear breaks.. otherwise -2C or so if we stay cloudy.

    ReplyDelete
  11. Encountered a major clear (sky) patch Northeast of Austin HwY 1W about 1pm today. That would be west and over lake MB

    Opposite of Friday pm when 2 to 4 cms of snow on same location Hwy 1W , with very limited visibility in blowing snow at 5pm. Fields were solid white.

    ReplyDelete
  12. Got a report of 50 cm of snow (20") at Pointe Du Bois from that lake effect event yesterday!

    ReplyDelete
  13. NWS Grand Forks has released their preliminary winter outlook for 2009-2010 (click on my name for link) Good discussion on overall influences and possible impacts on regional winter weather here. Overall, signals hint at a milder than normal winter this year with less snow.. and I for one am OK with that :)

    ReplyDelete
  14. Glad to see you guys got some white...amazing snow totals off of the lakes. We might get a dusting here in Grand Forks this morning... does look like the cold will relax later this week and the weekend

    ReplyDelete
  15. Convection popping up... one cell over central Winnipeg giving heavy sleet at the moment and very low visibility.

    ReplyDelete
  16. Heavy ice pellets continues... lawns and even concrete surfaces turning white. Enough low level warmth and moisture from the surface combined with cold temps aloft to produce significant convection along surface trough...

    ReplyDelete
  17. Well that was interesting.. just enough heat flux off the lakes to support ice pellets initially? Model soundings did not look favorable for sleet formation. Any snow out in Charleswood?

    Clouds appear very cellular on visible satellite, so it looks like we will see some pretty good clearing. However models (like NAM) hint at low level cloud coming off L Manitoba affecting Winnipeg and points NE. Will have to watch if lake effect clouds persist given subsidence occurring in wake of upper disturbance.
    Further complicating matters is that surface flow turns SW by morning. That will prevent YWG at least from bottoming out.

    The coldest temps should occur to the south and west of Winnipeg where centre of surface high (and best subsidence) will be located and there will be no low level moisture off the lakes.

    Only catch would be high, thin clouds possible moving into the SW corner of province by dawn. Those clouds would be associated with that broad area of warm advection at the mid and high levels which will ever so slowly shift NE and eventually moderate our temps. However those clouds if they do form may not be low or thick enough to get good counter radiation from.

    ReplyDelete
  18. Daniel..

    Yes, we got a couple of those convective snowshowers this afternoon in Chwd, but we got more snow pellets than ice pellets (solid white pellets vs clear) but no accumulation. Quite unstable today with the sun poking through and the cold air persisting aloft.

    ReplyDelete
  19. Skies clearing out nicely over much of southern MB this evening.. look for coldest temperatures overnight over western MB where the airmass is drier, with lows of -10 to -13C likely. For Winnipeg and RRV and SE MB, we'll likely be in the -5 to -8C range overnight due to higher dewpoints.

    ReplyDelete
  20. Rob!
    Half of the month is already over and I'm sure the month of October is averaging well below average!!

    Are we on par with 2002 so far with all these cold temperatures????

    ReplyDelete
  21. As of 12th, Winnipeg airport had a monthly mean of +3.2C while Oct 2002 was +3.8C by the same point. So we've actually had a colder start this year than October 2002. However, the last half of October 2002 was very cold, averaging -3.2C, with no days above 5C, and daily lows in the -5 to -12C range. That brought the final monthly average down to a record cold -0.5C, the only time that Winnipeg has had an average October temperature below freezing. So although we're on pace right now, we'd have to get even colder for the next 2 weeks to beat the 2002 record. Wouldn't that be something though.. having the coldest October on record after the warmest September on record? I don't think that has ever happened in our climate history to go from one extreme to the other like that.

    By the way, after the frigid October 2002, November finished a bit below normal, followed by a well above normal December. Snowfall was below normal in November and December, and for awhile, it was looking like we were going to have a brown Christmas.. until we got some snow on the 18-21st. 2002-2003 was also an El Nino winter, so there's hope that our cold October weather may not necessarily equate to an early winter.

    ReplyDelete
  22. You were right Rob about the snow pellets.. makes a lot more sense.

    We have a real dichotomy in terms of weather trends here in Winnipeg. How interesting that in almost 140 years worth of records, 5 of the earliest October snowfalls have happened since 1996. At the same time, most of the top rain on snow events during the winter period have occurred since 1998. This demonstrates the increasing volatility of our already variable climate.

    The global warming signal has been delayed and less defined for the eastern prairies and NW Ontario than for the northern hemisphere as a whole. I think we are seeing two processes occurring at the same time:

    1) general warming seen right across the northern hemisphere

    2) an increase in the west coast ridge/ hudson bay votex blocking pattern.. often accompanied by another upper ridge over Greenland.

    Whether no. 2 is a result of the Pacific Decadal Oscillation cold phase or a glitch of how the atmospheric system is readjusting due to global warming (or both) who knows. This seemingly has led to violent contrasts in our climatic conditions over the past few years.

    ReplyDelete
  23. According to the weather records that we have, global warming only affects our winters and springs. The summer trend is flat (ex. 2006 & 2007 were very warm - 2008 & 2009 were cold). The warm years tend to offset the cold years as far as summer goes. The climate models I have seen show our average temperatures staying relatively unchanged under global warming conditions. However, our weather will likely become more volatile, but even so, the extreme warm will then be offset by extreme cold.

    Other parts of Canada (and the world) are affected in different ways by global warming. Some areas will get colder, while most areas get warmer...with our luck we will be in the colder area! While our Jan-June period was well below normal, on a global scale it was one of the warmest on record.

    The fact is that people don't realize that what happens in their backyard isn't global warming - it is the global trend - as clearly stated in the term "GLOBAL Warming"

    ReplyDelete
  24. The Canadian Regional Climate Model (CRCM) gives 2-3 degree warming even during the summer months over the southern prairies by the middle part of the century.

    The warming signal (reflected in annual mean temp) at places like Regina and Winnipeg only appears in earnest during the late 70s/ early 80s. It actually matches quite well with the start of the PDO warm phase (which ended in the late 90s).

    ReplyDelete
  25. Daniel/Scott.. good observations. I moved to Manitoba in 1998 and the first few years here the weather was terrific and quite enjoyable. But since about 2002, the weather seems to have been getting more volatile, with more wild temperature and precipitation swings, and less predictable or "normal" weather. In the past 7 years, we've had

    - our coldest October (2002)
    - our coldest August (2004)
    - our warmest January (2006)
    - our driest July (2006)
    - our warmest September (2009)

    We've seen higher incidents of early and late season snowfalls (2002, 2004, 2005, 2009) as well as some record early season rainfall events (February 2009 and March 2004) Whether this is due to the effects of a shift in global climate patterns (climate change) or natural variability in a climate known for extremes, the weather does seem to be have gotten more volatile (less stable) these past few years. The question is.. is "less normal" our new normal?

    ReplyDelete
  26. Rob
    Wouldn't 6 records in 8 years be average if the records were 140 years old?

    If we have 12 months and X conditions such as
    Coldest mo, yr, season,
    Warmest mo, yr, season,
    Wettest,
    Driest ,
    Snowiest,
    Most Winter Rain,
    Most summer snow,
    etc.,
    we have a potential for 100+ records every year .

    ReplyDelete
  27. There are 13 Date related Normals in the Canadian Climate Normals 1971-2000. If we subdivide that by month (I know not all months have snow) hypothetically we have 156 possible records to be set each year.

    ReplyDelete
  28. Although we're not quite in the same league as Baseball, weather records could fill a good size book n'est pas?

    Do we have an author out there?

    There is at least enough material to fill a website:)

    ReplyDelete
  29. As far as temperature records go (warmest, coldest months), we've set 4 new monthly extremes in the past 7 years. In comparison, we had 5 monthly extremes set between 1971 and 2001, one of which was exceeded this decade. So the rate of monthly extremes has been higher this past decade than the previous 30 years. Prior to that however, we had 4 monthly temperature extremes set in the 1960s, with an extreme drought that decade (1961) as well as an extreme blizzard (March 1966)

    So, the question remains.. does the increased volatility in our weather these past few years just part of natural variability, or is a start of a new trend?

    ReplyDelete
  30. Rob!

    Looks like some heavy snow is falling in southern Manitoba today!

    North Dakota is expected to pick up around 5 cm of snow!

    I would expect similar conditions here in Southern Manitoba considering the radar are showing the snow bands heading this way!

    ReplyDelete
  31. Winnipeg is sitting a 3 C
    While Portage la Prairie is sitting at 0 C and snow!

    I wondering if that snow will change to rain in the city or could some of the cooler air sneak in and keep it all snow??????

    ReplyDelete
  32. Yep.. some snow heading our way.. although I wouldn't call it heavy. Portage is down to 2 miles in light snow, while Brandon is 3/4 mile.. almost moderate snow. Morden webcam shows a dusting on the ground. Looks like areas southwest of Winnipeg will see the most out of this.. maybe 2 - 5 cm. Should be into Winnipeg shortly although I doubt we'll see much accumulation with temperatures of +3 to +5c.

    ReplyDelete
  33. Can someone please tell me again how it can snow when the temperature is
    3 C????

    Winnipeg airport at noon is snow and +3 !!!!!

    ReplyDelete
  34. Speaking of records, what is the record for total snow in October?

    ReplyDelete
  35. About Records, theoretically the longer the comparative period measured, the less likely we are to establish or break a record unless the trend is continually in one direction. Warmer, Colder. Wetter etc. In other words if we've already recorded 130 Octobers odds are much greater that we won't exceed the extremes. Ironically the last decade is proving otherwise.

    One reason could be, that the temperature records and any others have not been consistently drawn from the same location. Apparently the Winnipeg airport location has changed recently and also I suspect the 19th century records would be from another location.

    Another reason is that we have created topographical alterations which may effect weather (not carbon based) such as the Garrison Diversion, Lake Winnipeg regulation, and the elimination of most prairie standing water by drainage systems . We know for example that spring Floods beget cooler spring weather. If we streamline the runoff we increase the likliehood and extent of downstream spring floods.

    Next spring we may see the effect of a totally new bridge crossing at Drayton . A bridge Higher and wider theoretically makes the water go downstream faster and faster. or as the people in Pembina might say Glub Glub. Last year the Drayton bridge acted as a major dam slowing the progress of water downstream. The faster the water gets to Wpg the cooler we are likely to be, and the more likely the water may be a solid.

    So is it Natural I don't think all of it is.

    ReplyDelete
  36. The record for most snowfall in Winnipeg for October is 38.6 cm back in 1919 while the greatest 24 hour snowfall for October is 24.6 cm on October 30, 1971. Let's hope we get nowhere near those records.

    ReplyDelete
  37. Anyone who was a Halloween participant in 1971 may remember the sky high snowdrifts on halloween day (after Oct 30 record) and biting cold that year. Trick or treating over 2 meter front door snowdrifts. A snowdrift on Carberry cres. in St James backing on Saskatchewan ave reached the roof of the Bungalow. and this was October. That drift was still there 5 shivering cold months later.

    ReplyDelete