Thursday, March 18, 2010

Cold front to bring strong winds, falling temperatures this afternoon into this evening

A low pressure system tracking through central Manitoba will drag a sharp cold front across southern MB today bringing an end to the current mild spell. The cold front along the MB/SK border this morning will push across Winnipeg and the RRV this afternoon. The front will be marked with northwest winds of 50 km/h with gusts to 70 or 80 km/h at times and falling temperatures. There is a chance of some showers or flurries with the frontal passage but the bulk of the precipitation with this system, falling as snow, is expected through the Interlake and central MB where several cm may fall. As the colder air deepens this evening, Winnipeg may see a dusting of light snow with gusty northwest winds continuing along with below freezing temperatures. That could slick up some city streets and bridges so be prepared for local icing. Clearing conditions are expected Friday along with diminishing winds.

20 comments:

  1. You can check real time winds from Winnipeg airport with their live runway information link via NavCanada (click on my name for link) Wind speed is in knots.. basically double it for km/h. Upper air analysis this morning shows 50 knot winds at 850 mb and 40 knots at 925 mb upstream with cold advection and some good pressure rises coming in.. that should give us 70 km/h gusts this afternoon into this evening behind the cold front, perhaps 80 km/h at times in some spots.

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  2. An update on the Flood Briefing Page that ROB posted sometime ago showing the almost at crest height for this weekend from Fargo to Pembina. Click on my name or go to

    http://www.crh.noaa.gov/fgf/briefing/floodbriefing.php

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  3. Thanks Jim. It looks like those projected peaks at Pembina and GF are a little lower than earlier thought? That would be good news. Overall, the weather has been very favourable for this year's flooding outlook which had the potential to be much worse given the snowpack and soil moisture south of us.

    For today, winds aloft have dropped into the 30-40 kt range..which should translate into gusts of 60-70 km/h for us. I don't think we'll see those 80 km/h gusts forecast earlier.

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  4. the flood brief page has received excellent comments. It was developed by our office and may be a nationwide standard. The crests forecasts for GF are the same 47-49 as they always been. No biggie here...but I live in East Grand Forks MN so with two of the 3 bridges closed between the two cities it will mean a long commute across the river.

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  5. Rob Would EC,forecasts tell us the winds will rise in two weeks to 100Km without telling us they will reach 95K this weekend and remain there peaking at 100km in 10 to 14 days.

    Our provincial flood forecasters appear to have produced the equivalent to that.

    It would help if Manitoba Spring Flood Outlook yesterday, gave a timetable for the river stages as they do on Dans pages. Knowing it will be at peak levels after the end of the month is not quite the same as knowing the River will be within a foot of the crest in 4 days and stay there for two or more weeks. Mentioning the flooding starts next week and crests at the end of March...and not mentioning that it will be near 2006 levels starting Monday, is a bit of an understatement.

    In todays (I agree with the excellent reviews Dan) Grand Forks Flood Briefing Page Links ,

    Oslo 20 miles this side of Grand Forks will reach 38 feet tomorrow matching 1997 and just under 2009 levels .

    Drayton 30 miles from Emerson will reach 42 feet equaling the 2006 crest by Midnight Monday. (within 3 feet of last years Peak)

    Pembina 2 miles from the Emerson will be at 47 feet just over 4 feet below 2006 levels Midnight Monday.and at could peak by Wednesday.

    One would think these levels require some very drastic Manitoba road closing action within days and perhaps hours... Not 2 weeks from now.

    Did I mention flood prep needs to be completed this weekend not the week after as suggested by MB

    And yes, I alerted MB Highways who thought they had till the end of the month.


    Todays rant with syntax checked is brought to you with apologies for length.

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  6. Rob!

    EC is calling for -16 tomorrow night!!

    You think that is a bit of a long shot or you think it could be possible??

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  7. Chris - Windsor Park7:30 AM, March 19, 2010

    Did I ever get duped by EC.
    2 ays ago they were calling for
    -9 on Sunday ....today they are calling for +8 on Sunday. A 17 degree difference! I should know better.

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  8. Chris!

    I think you should split the difference between the two extremes and that should be the temperature for Sunday!!! LOL!

    That is my scientific way of getting the temperatures!

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  9. Chris.. You can blame that big forecast swing for Sunday on the major flip in the model for that day. Originally, they were showing a low tracking through the Interlake and dragging a secondary push of cold air into southern MB with gusty north winds. Other models were in general agreement on this scenario. Models then started to back off on this secondary cold push, with a weaker low going through the Interlake. Hence the warmer forecast. But I agree, that's quite a dramatic change in just a couple days.. but that's what can happen in the spring depending on what side of the cold front you're on!

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  10. Models were a bit too eager it seems in pushing arctic air south - not surprising considering the lack of snowcover etc. Active NW flow sets up with several clippers riding along baroclinic zone that will be draped across international border. First comes thru ealy next week... tough call on precip type depending on time of day and exactly where front ends up stalling. In these situations Winnipeg gets hits with precip, clouds while American RRV basks in sunny, warm sector. Potential for continued rapid run off down there it would appear...

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  11. Rob

    What is the record warmest March Mean and are we anywhere near it?

    Jim

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  12. Jim..

    Warmest March on record in Winnipeg was way back in 1878 at +1.6C (click on my name for climate summary that month). This followed Winnipeg's infamous warmest ever winter of 1877-78 (during an extreme El Nino event with world wide impacts). March 1910 was the next warmest at +1.2C followed by 1973 at 0.5C and 2000 at -0.1C. As of the 18th, Winnipeg airport had a monthly mean of -1.2C, good enough for 6th place currently, but that average will go down with this little cold snap. We'd have to warm up considerably for the last 10 days of March for us to break a record.. but a top 10 finish is quite possible.

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  13. Wow, could not believe that winter of 1877-1878 when I checked it out. Only one month, January, had an average daily maximum below zero! Now that's a winter that was completely skipped! In addition, from November to March,106,7 mm of rain fell, with only 18,8 cm of snow!!

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  14. Rob

    The forecast has changed for monday and they are now calling for snow. TWN is calling for 5-10cm and EC is just saying periods of snow. How much do you think is coming on monday?

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  15. Mean temperature at my weather station is +0.2C, the mean temperature at the Steinbach airport is -0.4C.

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  16. Daryl..

    Models are coming in line with an Alberta clipper system moving into the Dakotas Monday, spreading an area of precipitation, mainly snow, across southern SK and southern MB. Precipitation may start as rain first over Winnipeg/RRV Monday afternoon before changing to snow Monday evening, with several cm accumulation possible Monday night. Canadian GLB is most aggressive with amounts showing 5-10 cm possible for Winnipeg, while NAM shows about 2-5 cm and GFS shows trace amounts. 5-10 cm looks high given there will likely be some melting at first over the RRV, but 2-5 cm by Tuesday morning is possible. We'll see how the models trend with this system, but it does appear we may be waking up to a covering of snow once again Tuesday morning. Welcome to spring!

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  17. Monday forecast for Winnipeg now calls for a 60% chance of showers.. exhibiting the slower and slightly milder solution for Monday. Models still indicate a changeover to snow Monday evening with a couple cm possible Monday night. If so, this would be the first snow in Winnipeg since Feb 22nd.. a full 4 weeks ago.

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  18. This bizzare winter continues.. while we still await our first snow in weeks, Dallas picked up another 1.3" of snow last night, their latest March snowfall since 1937. This brings their seasonal snowfall up to 17.1", second only to the 17.6" in 1977-78. Up to 8" (20 cm) of snow was reported just northeast of Dallas overnight.

    As for us, models continue to hint at the possibility of some snow over southern MB Monday night. GEM is most aggressive with amounts with a few mm of rain in Winnipeg changing to some wet snow by Monday evening. Could see a minor coating although system will be moving out fairly quickly, and bulk of snow should melt as it falls. GEM hints at slightly higher amounts to the southeast of Winnipeg into NW Ontario. NAM guidance much lighter on precip amounts with this clipper.

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  19. Looks like most of the precip from this clipper will slide to the south of Winnipeg along the US border and over northern ND as rain today, clipping SE MB this evening. Our snowfree March should remain intact.. for now. Another chance for some snow Wednesday with another clipper moving in..

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  20. Rob!

    Hopefully in about a month we will be talking thunderstorm chances instead of snow chances!

    Maybe this summer will be a HOT and Steamy one with lots of storms.

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