Sunday, April 07, 2013

No break in sight as abnormally persistent winter pattern continues..

The endless winter of 2013 (right) is tough to accept
after 2012's incredibly early spring (left)
Photo tweet courtesy of @jjcwpg
The winter of 2012-13, which unofficially began over much of southern MB on Nov 10th last year with our first widespread snowfall, continues unabated through the first week of April. Snow fell across southern MB again today, with 2-3 cm of wet snowflurries generally melting on impact. Nonetheless, it was enough to crush any signs of spring in the area, with an extensive 39 cm snowpack still intact in Winnipeg and throughout southern MB. (As of Wednesday April 10th, snow will have been on the ground in Winnipeg for a solid 5 months) And it looks like the below normal temperature pattern will persist all week, and possibly into next week as well. As of today, Winnipeg has gone 28 straight days below normal dating back to March 10th, and that streak will likely grow to 35 or even 40 days as "normal" high temperatures climb towards the +10c mark by mid April.  In fact, Tuesday morning may see temperatures dropping towards the -20C mark in Winnipeg.. which if reached would be one of the latest occurrences of -20C weather since records began in 1872. (Latest -20C temperature in Winnipeg was a -20.0C reading on April 12th 1881)

Luckily, the weather should be dry much of the week, with little in the way of organized precipitation expected over southern MB.  That may change by next weekend however, as long range models are hinting of a possible storm system that may impact southern MB and the RRV next Sunday with potentially significant precipitation, and yes, possibly heavy snow.  It's still very early, but it will be a system to watch over the coming days. Stay tuned...

47 comments:

  1. Rob, is the thinking the same as far as this ugly pattern breaking in the 2nd half of April which would finally bring us some warmer temps?

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  2. There continues to be signals that the blocking pattern will relax by mid April, which should allow more frequent pushes of milder airmasses into southern MB for the second half of April. However, given our extensive snowpack, that milder air may be delayed another week or so as we melt off this snowpack. A lot of energy is going to be needed to get rid of all this snow across southern MB and southern SK. That being said, I have seen 30 cm snowpacks disappear within a week given the right conditions, so it is possible that if the pattern turns, it could go fairly quickly.

    The wild card is that system next Sunday. If we get significant snowfall, that may delay things for another couple of weeks at least.

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  3. Rob, just wondering if next weekends storm system is expected to be a colorado low or another clipper. Thanks

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  4. This coming weekend could at least give us something to watch, while huddling under the blankets.

    CBC Manitoba only gives a 20-30% chance of precip, public forecast is 60%, TWN says 80% with 5-10cm of snow. GEM and GFS both show around 10-15 cm.

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  5. >> Anonymous said...Rob, just wondering if next weekends storm system is expected to be a colorado low or another clipper.

    It's more of a clipper than a Colorado low, but it could be a fairly strong one. Storm will be pushing in over BC from the Pacific, then tracking over the southern prairies or northern Plains. Some of last night's guidance was suggesting a track a little further north which could put us more into mixed precip or possibly rain in the RRV.. but it's still several days away. Will continue to monitor..

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  6. Rob, where are you obtaining your updated Arctic Oscillation indexes? I checked the CPC website and it hasn't been updated since March 31.

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  7. >> Andrew said... Rob, where are you obtaining your updated Arctic Oscillation indexes? I checked the CPC website and it hasn't been updated since March 31.

    Click on the following link..

    http://www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/ao.sprd2.gif

    updated as of today..

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  8. NWS now forecasting 20-40 cm of snow across much of western and central South Dakota tomorrow into Wednesday with that major storm system coming out of Colorado. Luckily looks like bulk of snow should remain just south of the American Red River valley.. hopefully it stays that way.

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  9. Yikes. Sure hope today's Euro for next week doesn't pan out for us. After hitting us with 10 cm of snow Sunday (which is bad enough), they slam us 3 days later with a major Colorado low dropping 20 cm of snow over Winnipeg/RRV. The saving grace is that it's 10 days out, and things will likely change. But that is a scary proposition if that scenario works out..

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  10. rob,
    how much snow/rain do you think we'll get from the clipper system this weekend.

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  11. rob,
    do you think it will go down to -21 to night?

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  12. wow! we are so lucky we are not getting hit by this Colorado low, 20-35 CM of snow in nebraska. if we had goten it there might have still been snow cover in june!

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  13. i came to winnipeg in late february, early march to see the jets and experience winter and i love it although it was fairly mild so the locals said. got to see a nice snow. i'm from louisiana and long for snow and long winters. its 27c here today and will only go up to miserably hot for 6 months. i think yall's weather is neat.

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  14. Anonymous..

    Glad you got a taste of the great white north! But I'll gladly trade 6 months of your heat for 6 months of our snow! Go Jets! :)

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  15. the heat is boring. i'm a weather nut like you and here in the summer its the same forecast day after day after day. high 94 low 74, 20% chance afternoon thundershowers. most of the summer the weather news takes about 2 minutes. of course there are those pesky late summer hurricanes.

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  16. Low of -20.2c at YWG airport this morning... not a record low for today which was -21.6c in 1997, but ties 1997 for 3rd latest -20c reading ever in the city since 1872.

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  17. Rob, do you know where the Weather Network takes their readings from? They are always different than the airport, and also different than the Forks site. Do they have their own weather station somewhere inside the city?

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  18. >> Rob, do you know where the Weather Network takes their readings from? They are always different than the airport, and also different than the Forks site. Do they have their own weather station somewhere inside the city?

    I assumed it was from Winnipeg airport. Although I must admit, I don't watch them enough to say for sure.

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  19. Rob, what's the latest as far as the storm system Sunday and Monday? are we still looking at a snow event of 10 to 15 CM possibly or will it be a mixed snow and rain event with lesser snow amounts as a result?

    Also, do you think Saturday's forecast of +6 is a bit of a stretch?

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  20. Thankfully, Euro has bailed on that Colorado low scenario for us next Wednesday, but it has increased amounts for Sunday-Monday system with 24 mm of wet snow indicated for Winnipeg. GGEM and GFS have similar amounts, so it's looking more and more likely that we'll be seeing some significant precip amounts with Sunday's system. Actual snowfall amounts may not be as high as models are suggesting due to melting with temperatures near 0C, but we could be looking at 15-25 mm water equivalent when it's all said and done, with perhaps 10-15 cm of accumulated snow. Blechhh. Stay tuned..

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  21. NAEFS and CPC long range forecasts are still giving next to certain chances of colder than normal temperatures in 2 weeks from now; looks like we'll have to put up with winter for a while yet...

    http://www.weatheroffice.gc.ca/ensemble/naefs/semaine2_combinee_e.html

    Strangely this extended winter doesn't bother me too much; I just learn to accept it as is and be thankful of our varied climate. I think I'm one of very few!

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  22. You aren't alone. I'm loving it :)

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  23. accuweather has no precipitation for sunday or munday.

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  24. >> Anonymous said... Accuweather has no precipitation for sunday or munday.

    Likely because that forecast is based on the GFS model, which had the storm missing us on this afternoon's 18Z run. The 12Z run had 20+ cm for us. We'll see what tonight's 00z run says.. but right now, most models are suggesting we will see something Sunday into Monday.

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  25. Now accuweather says "A chance for snow", has a POP 0f 35%, but no snow accumulation. The latest GFS however has about 3cm of snow. Other models showing much more. One CMC Ensemble member even has 60cm!

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  26. Interesting that the last 2 runs of GFS has this storm missing us as it has the storm being absorbed by a more potent storm in the central U.S. plains. Euro, GEM and Ensemble models all still show lots of precip for us.

    Rob, is the GFS an outlier at this point?

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  27. GFS is the weakest on Sunday's storm, taking the main energy further south while GGEM and Euro are further north and stronger on the surface low. Today's GGEM has taken heaviest precip area a little further south over southern RRV and ND, with about 5-10 mm noted for Winnipeg. Euro is still furthest north and strongest with storm with 15 mm noted for Winnipeg (down from 25 mm from last night's run)

    Putting it all together, I think a GGEM/Euro solution seems more likely than the GFS, with some precip likely Sunday into Monday. Snowfall amounts will vary depending on surface temperatures, but probably 5 to perhaps 10 cm of wet snow not out of the question for Winnipeg especially Sunday night with higher amounts possible over higher elevations to our southwest.

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  28. Wow not often you see ''freezing rain at this heavy'' in the public forecast. Looks like a decent ice storm for southern Ontario coming up. That'll pay for the 3 consecutive days with thunderstorms in the area!

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  29. Yeah, some areas northwest of Toronto could see some pretty heavy ice accumulations overnight through Thursday night. It could also mix with ice pellets which would cut down on the freezing rain amounts. Very tricky forecast based on 1 to 2c variation in temperature!

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  30. One of those days where the airport was not representative of conditions in the city today. Airport barely made it to freezing mark, while many areas of the city were in the +2 to +7C range this afternoon, thanks to sunshine and light winds.

    Note that Winnipeg airport has yet to hit +5C this year. The latest that Winnipeg has reached the +5C mark was April 15th in 1950.. the year of the big flood.

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  31. I just took a snowpack reading. in my front yard in the south end of the city there is 42 CM of snow. you wonder if we will still have a few centimetres in june! Oh and rob how long do you think it will take for the wet snow to melt from the sunday into monday system. Also i just realized that this upcoming storm system is the 4th snowstorm in a row that is sunday into monday!
    the february blizzard, the storm on the 4th of march, the saint patricks day storm, and this one ahead! This getting really strange.

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  32. rob, forecast.io has no precipitation for sunday or monday, do you know where they get there data from?

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  33. this ice and rain storm in southern ontario looks pretty bad. EC says that windsor could see as much as 80 mm of rain. strangely i would rather have heavy snow.

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  34. Yeah, another reason to hate Mondays!

    As for Sunday's system.. I think the best chance for accumulating snow for us will be Sunday night as we lose the diurnal heating of the day, and surfaces cool somewhat while the system continues to spread snow over southern MB. I still think we could seeing 5 cm or so by Monday morning even though latest guidance is backing off on amounts from earlier runs. How fast it will melt will depend on how much we get, but it looks like we cool off behind this system for next week so it may take a few days.

    I'm still pinning my hopes on a pattern change after the 20th as the long wave ridge starts building over western NA and heights start rising over the Prairies.

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  35. Wow Yellowknife hit 9°C today.. and we can't even hit 5°C!

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  36. Looking more like North Dakota will get the brunt of Sunday's storm, with Winnipeg on the northern edge. Oh well.

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  37. Saturday's high has been brought down from 7 to 3C. Makes more sense.

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  38. Hope this kind of pattern doesn't carry over into the summer, Winnipeg constantly being on the edge of this and that while all the fun weather just misses us. This of course coming from the perspective of someone who enjoys extreme weather. Ready for the comments to bash that :)

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  39. That forecast of "periods of rain" for Sunday is terribly misleading. This system will be mainly snow for southern MB, including Winnipeg. The precip may start off as wet snow during the day Sunday, possibly mixed briefly with rain, but it will be all snow by Sunday night and continue into Monday. Again, amounts are tough to call because snow will likely be melting during the day Sunday, before accumulating Sunday night into Monday. General model consensus is for about 10 mm of melted precipitation for Winnipeg Sunday into Monday, of which about 1/2 which may actually accumulate as snow. Higher amounts being indicated over southern RRV, with GFS showing snow lingering into Tuesday for Winnipeg with 10 cm or more possible. Will continue to monitor to see if there's any northward trend on this system.

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  40. Rob, national weather Service in the U.S. has indicated that another storm could affect the Dakotas around Wednesday or later next week. Could this be a potential storm threat for us as well?

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  41. >> Anonymous said...Saturday's high has been brought down from 7 to 3C. Makes more sense.

    That is the likely the last chance for Winnipeg airport to make it to +5C before the 15th. If not, this will be the latest date in 140+ years of records that Winnipeg has hit its first +5C reading of the year. That is quite the staggering statistic.. especially in light of last year's record early warmth, and some even colder springs in the past. So we basically go from one of the earliest springs on record last year to one of the latest this year. Mother Nature sure likes messing with us.. doesn't she? :)

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  42. >> Anonymous said...Rob, national weather Service in the U.S. has indicated that another storm could affect the Dakotas around Wednesday or later next week. Could this be a potential storm threat for us as well?

    Right now, most models show that storm missing us to the south and east, affecting areas mainly south of the border into the Great Lakes.

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  43. Rob,
    After (if!) the jet stream pattern returns to normal and the AO turns neutral, how long will the lag effect on temperature last? I assume that even when the snowpack is completely melted, it'll take a while for temps to rebound to seasonal values. For example, do you think it's more likely than not that May will end up below normal?

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  44. Andrew..

    Once the snow goes, we should be able to warm up fairly quickly.. as long as the upper pattern returns to a more normal setup. I'm hoping we turn around with a sizzler of a May!

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  45. 12Z GGEM looking ugly for Winnipeg/RRV Sunday night into Monday. Cold north winds and maybe 5-10 cm of snow?

    The only saving grace to this miserable spring is that we likely won't ever experience a worse one in our lifetimes (I certainly hope)

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  46. Thank goodness that Colorado Low to our south ended up missing us this week... It brought record snowfall to South Dakota with over 50 cm in some areas.

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  47. Snowiest day on record for Rapid City SD with that storm.. 20" (50 cm) on the 9th, with a 3 day total of 28" (70 cm) Click on my name for storm snowfall map.. impressive totals over southwest SD.

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