Monday, January 11, 2010

January thaw spreading across Prairies

A flow of mild Pacific air is spreading across the western Prairies today, with above freezing temperatures moving into Alberta and southern Saskatchewan. This mild air will move into southern MB Tuesday and Wednesday, with above freezing temperatures likely in many areas, especially where southerly winds blow down from higher terrain. Warmest spots will likely be in the Dauphin and McCreary areas where downslope winds from the Riding Mountains will send temperatures up to +7 or +8C. Elsewhere, high temperatures over southern MB will be in the 0 to +3C range, although temperatures will likey remain slightly below freezing in the river valleys where cooler air gets trapped. Slightly cooler weather is expected Thursday but tempeatures are expected to remain above normal over the next week.

39 comments:

  1. Why did temps along the River remain at-13 to -14 this morning when the rest of the city cooled to -18 to -20?
    Did the fog have any impact?

    Usually it is cooler here.

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  2. Dan GF I'm confused (happens easily ) re in house climate persons comments of El Nino Filters for /-AO/-PDO. Particularly the result years of 69 (Negative PDO) and 77 (First Positive PDO year)

    Different filter results at my name or http://www.atmos.washington.edu/~mantua/TABLES2.html

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  3. Jim.. Are you downtown? It was a a few degrees warmer downtown because of the urban effect. Most places in Winnipeg outside the downtown core got to the -17 to -20C mark this morning.

    Latest guidance showing that Winnipeg/RRV may get a bit of a southwest flow tomorrow, which would help us climb above freezing. Latest UMOS guidance has Winnipeg up to +5C Tuesday which seems a bit optimistic. The key to getting above zero tomorrow in Winnipeg is to get some westerly component with our surface wind. BTW, record high for Winnipeg tomorrow is +5.7C in 1987.

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  4. On the River 1k north of Bishop Grandin. Normally as low as the airport whenever there is a south wind.

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  5. U of M and Waverly were also warmer overnight (-16.7) versus Whyte Ridge and Riverpark South at near -18.5 to 18.9

    Irony..Warmest air was on the Lowest land. Fog tends to follow that pattern?

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  6. Rob!

    If this warm air keeps up for a while it might melt most of our pathetic snowpack!!!

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  7. Dauphin Manitoba warmer than Orlando Florida!!
    Now I understnd why TEAM USA beat the Canadian Junior Hockey Team in Saskatoon.

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  8. Daniel.. there will be some melting of the snowpack over the next couple of days, but it's going to take a lot more than a couple of mild days to make a significant impact. Consider southern AB where it's been +7-10C for the past 3 days.. yet they still have snow on the ground. And they can get rid of snow a lot faster than we can.

    I'm also not convinced Winnipeg will get above freezing Tuesday. GEM temperature guidance has not been handling the valley effect very well in SK today. Consider Regina, stuck with a SE valley wind this afternoon, only got up to -5C. GEM was predicting +2C for them. Methinks it will have the same problem with the RRV tomorrow..overdoing highs with a southerly valley wind. Above freezing highs likely over western RRV as well as east of the valley in the trees (Pinawa, etc) as the warm air "skips" over the valley. Even so, Winnipeg should still get to the 0 to -2C mark Tuesday.

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  9. The USA Snowcover map has dipped well over 1000km further south east than at the same time in 07 and 08 . Montgomery, Alabama, Atlanta Georgia, ahve as much snow as we do .
    See
    http://www.intellicast.com/Travel/Weather/Snow/Cover.aspx
    or
    http://www.nohrsc.noaa.gov/interactive/html/map.html

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  10. I would like to echo some of the previous comments on what a valuable resource Rob's website and blog are... it provides an interesting oppurtunity for exchange of ideas and 'cross-pollination' (lol) between American and Canadian meteorologists. Continued success and all the best for 2010.

    *******************************************

    Already +2 C at Dauphin where warmer air and SW flow have mixed down to the surface while Regina still plagued by valley effect as Rob mentioned. Local topographical effects swamping overall synoptic pattern making it difficult to tell where 'true' warm front is.

    Yeah unfortunatley we look to stay stuck with 'valley effect' during the day tomorrow with south winds. However watch for a burst of mixing tomorrow evening/overnite as trough moves through and flow turns WSW for brief period. Given that snow cover is minmal in the open country.. do not discount the possibility of YWG in particular to jump briefly to 3-4 C with temps then falling back but holding steady above freezing thru Thursday.

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  11. Edit... temps should stay above freezing thru *Wednesday*

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  12. Thanks Daniel..

    Yes, if we can get that WSW flow in here tomorrow evening, we could get above freezing temps at night! That will likely happen in Regina tonight as their SE valley wind shifts into the SW..

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  13. Boy is that wind strong out there. Will those gusts continue all night into tomorrow?

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  14. Yep, strongest winds should be through tonight into tomorrow morning gusting to 60 or 70 km/h, then they should drop off in the afternoon through the evening. Note that Treherne in the western RRV gusted to 73 km/h past hour..

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  15. Temperatures struggling to rise in the Red River valley this morning with that southerly wind. Winnipeg only -9C at 10 am, while GEM UMOS was forecasting -2C by this time. GEM not handling valley effect well at all (much like Regina yesterday, and Winnipeg on Saturday when GEM overforecast valley temperatures by 5-7C) As a result, look for highs around -2C for Winnipeg later this afternoon.

    Meanwhile, temps have already climbed above freezing this morning in the usual downslope areas.. including Dauphin (+2C) and Boissevain (+1C)

    Winnipeg has a better chance of going above freezing Wednesday (around +2C) as our winds shift into the west in the afternoon and we get better mixing of the warmer air aloft.

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  16. Rob!

    Good job on today's temperature forecast for Winnipeg!

    Environment Canada was going for above zero but you told why you thought it would stay below zero!

    Now look who back down on their daytime highs!!! (ahem)

    Good call.... you should work for Environment Canada :>)

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  17. Thanks daniel..

    Actually, I do work for EC.. almost 25 years now. I just don't like to advertise it because I want to make it clear this site is my own personal site with no affiliation whatsoever with EC. Any comments expressed here are my own and do not reflect the opinions or policies of EC.

    Temperatures of +3C as of 1 pm over favoured downslope areas including Portage, Dauphin, and Boissevain. Winnipeg slowly creeping up there, -7C as of 1 pm. Even at these temperatures, roads are starting to get wet and messy in the city (thanks to that salt/sand mix). Say goodbye to your clean car for awhile and stock up on the windshield fluid. It'll be like this for the next week at least.

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  18. Rob

    I thought EC moved there entire operation west (Calgary I think) Obviously that must be wrong. Is there a full weather center in Winnipeg or just a small crew to mantain the instruments etc.

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  19. Yes, EC has a weather centre in Winnipeg responsible for public forecasts and warnings for Manitoba, srn SK, and Nunavut including Baffin Island (yeah, a huge territory) There is also a forecast center in Edmonton that covers Alberta, nrn SK, and NWT. There are 7 main EC weather centres across Canada, namely Vancouver, Edmonton, Winnipeg, Toronto, Montreal, Halifax and Gander. There are also 2 aviation forecasts centres, one in Edmonton for western Canada and one in Montreal for the east.

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  20. Thanks Rob

    I always had the mistaken opinion that forecasts were not as good as they used to be because EC had shut down the Wpg branch but that might just be more of a myth or that Manitoba's weather station has to big of an area to monitor.

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  21. Well I talking to someone I know who lives out in Elie and they say it is no warmer than in Winnipeg so that warm air is still to the west of them!!

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  22. Still hard to believe just 80 km west of Winnipeg it can be almost 10 degrees warmer, highliting the role of topography and land cover in our climate.

    Hey all we need to do is build a giant hill along the south perimeter that could also double as a dike ... haha. But seriously, the province should encourage farmers to diversify their land cover with more shelterblets, woodlots etc. They should also discourage burning and tillage, finding ways of leaving more stalk standing from the crops. The RRV basin is an unatural wasteland with vast stretches of bare soil in some cases.. even the native landcover (tall grass prairie) has a significantly more favorable radiative budget and allows for a more even distribution of snow cover,

    Anyways.. that trough out to our west doesn't appear to move thru until sometime tomorrow afternoon. If anything, surface winds back more to SSE overnite even as thermal ridge at 850 hPa (with riduclously warm tmeps of +11 C) crests over us. There is still the potential for very warm temps tomorrow as hopefully WSW flow will finally punch thru RRV inversion and 850 temps remain around 8 C.. some records will likely fall tomorrow especially outside the RRV proper.

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  23. Any big storms over the next week or two possibly? On TWN, it keeps saying that rain is coming. Highly unusual this time of year.
    And Rob, how warm do you think it could get on Saturday? Does it look like another shot at above zero temps?
    Thanks

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  24. +4 C forecast for Winnipeg tomorrow!!!

    I'm getting out the lawn chairs and suntan lotion right now!

    Ok......well maybe that's a little excessive!!!!

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  25. In Silver Heights we only reached -5.6C at 2:30pm this afternoon. The cold air trapped in the RRV just wouldn't budge. Here's hoping we can crack the zero mark on Wednesday. We will need a more westerly component to our wind flow, but an approaching disturbance might give us that shift late Wednesday. Looking at the tephis today, it was a pretty impressive inversion.

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  26. Well, valley effect was in full gear today, really doing its thing to keep temperatures suppressed in the RRV. I'm surprised we couldn't even crack the -5C mark, which means GEM was a whopping 10C off its projected temperatures for Winnipeg today. Today's lesson.. never underestimate the power of cold air in the valley.

    This puts our forecast low tonight of -8C in jeopardy with clear skies and lighter winds. We may even see dense fog or low cloud developing in the valley as low levels saturate. Then tomorrow is an interesting day to predict the high. We stay with a valley wind most of the day before a shift of low level winds into the west by late afternoon or evening. Thus we will likely stay below freezing much of the day again, before a possible jump to the freezing mark or +1C late in the day or early evening. That of course will depend on the timing and strength of a westerly flow developing.

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  27. Only got to -4C in Steinbach today. The NAM has been handling this pattern fairly well. It has been cooler than most models, but that ended up being the correct solution. I am expecting a high of +1 or +2 in Steinbach and Winnipeg for tomorrow.

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  28. jewels.. looks like it will be staying mild through the weekend into next week. Favoured downslope areas will have the best chance of getting above freezing this weekend, RRV looks like we'll be slightly below.

    BTW click on my name for an image showing the impressive warm air inversion over YWG that Dan was referring to. +10C at 3000 feet, -6C at the surface.. darn that valley.

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  29. Yeah following the dry adiabat down from the top of the inversion at 900 hPa yields 23 C ... Mamma mia lol

    Tomorrow's temp trends remain enigmatic. Flow does turn SW by 2-3 PM (lets hope sooner than that) but will just be too lite in the vicinity of the trough (~5 knt)..think we will have to wait for cold advection/WNW flow and associated 'gustiness' to mix down warmer air tomorrow evening. I still expect temps to finally make their move above freezing at this time and then fall back (my initial post was correct lol). If winds are strong enough we may hold steady on Thursday or claw our way back up to zero with 850 hPa temps near 0 C and WNW winds.. but at this point flow looks too slack again.

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  30. Jim...in regards to the analog years mentioned in your earlier post I will have to look at that or pass it on to someone more knowledgeable.

    In regards to temps...would have to agree it may well take til very late in the aftn or early eve til we get to 0C just after wind shift. Fine by me...I prefer not to see 0C til March....

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  31. Whoa!!!
    I wonder how MCCREARY went from +8 C down to -1 C in a hour with a north wind last night????

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  32. Dan GF Thanks for the update .
    From the EC Winnipeg results the last 7 months resembles 68-9 with a cold wet July and August, warm September with extremely dry November thru Jan 15.

    More importantly a similar PDO, ENSO,( El NINO) pattern and an Extreme Negative AO . .

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  33. I know this is completely off topic but .....it sounds like a very tragic situation in Haiti !!!!

    The biggest earthquake in 200 years for that area!!!!!

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  34. Remember that discussion about air temperature and windchill? According to this University of Manitoba webcam, it is -9 °C when Whyte Ridge reports -2.3 °C.

    http://www.umanitoba.ca/webcams/camera2.php

    That's because the fossils at the UM post only the windchill without stating that it is windchill. I've tried to get them to change, but it's hopeless. Nothing like making it worse than it is.

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  35. Daniel P, a friend of mine said that 100 000 people died from that earthquake. About 1/7th of the city of Winnipeg! As well, over 3 million people were affected by that earthquake in Haiti. It sure is quite tragic. It was a 7.0 on the Richter scale.

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  36. Forgot to mention, and to avoid confusion, just to say that 100 000 deaths is most likely an estimate and not exact.

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  37. Jewels!

    There are even estimates as many as 500 000 people !

    That is an earthquake of epic proportions!!!

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  38. Yeah that was a major earthquake, CNN says might make the top 10 list of deadliest earthquakes! Pretty shocking knowing that around 10 million people live there and around more then 200 thousand died, wich is around 1/50 of their population! They also mentioned that more then 25 aftershocks followed (aftershocks being of magnitude of around 5.0), this to me is incredible and very saddening.

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  39. What is also interesting is the use of the on air Meteorologist to explain the physics of the quakes.

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