Monday, March 07, 2011

Storm system threatens snowfall for Friday.. risk of freezing rain

Long range models are indicating the possibility of a storm system that will track across North Dakota Friday threatening snow and some mixed precipitation (freezing rain, ice pellets or even rain) across Southern Manitoba. Preliminary models suggest snow will spread over southern MB Friday possibly mixed with some rain or freezing rain initially. It's too early to say how much snow may accompany this system but early estimates are for at least 5-10 cm of snow across the TransCanada corridor and potentially 10-15 cm over parts of southern MB. Stay tuned on this potentially wintery finish to the work week.

12 comments:

  1. Dan P That 8C > last hour rise at Robs has me believing.

    Spring can't be that far away.

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  2. Consensus so far on Friday's system leaning towards some mixed pcpn Friday morning over the RRV (wet snow, freezing rain, ice pellets, freezing drizzle or even rain depending on if surface temperatures can get above zero) changing to all snow by afternoon as storm intensifies and digs into ND drawing colder air into srn MB. Snow may become heavy at times by Friday evening into Friday night with 5-15 cm possible over RRV by Saturday morning. Snowfall amounts will depend on how quickly transition from mixed pcpn to all snow occurs. Increasing northerly winds Friday night along with falling temperatures could also create problems with blowing and drifting snow. Right now, the "60% chance of flurries" Friday into Saturday looks to be underestimating this event for Winnipeg and RRV.

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  3. On sunny days with light winds, you'll be seeing noticeably warmer readings inside the city (including my backyard) than outlying or more exposed rural areas due to that stronger March sun and the urban heat island effect. Likewise forested areas such as the Whiteshell and over northern MB will see increasingly warmer daytime temperatures as that March sun gets stronger.

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  4. Driving yesterday on Hwy 3 and the west perimeter produced similar variations between Fort Whyte -19 and Headingley -24 both open areas. At the west perimeter and Portage Ave -17 ( that might have been the combination of New Car Hot Air and Tim Hortons.lol)

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  5. Friday's system is looking more and more impressive with each model run!
    Winds look to me a major factor!

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  6. Will this system in ND have any effect on S. MB tonight.
    Graphic
    http://www.crh.noaa.gov/wxstory.php?site=fgf

    Noon Hour Warning
    http://forecast.weather.gov/showsigwx.php?warnzone=NDZ027&warncounty=NDC035&firewxzone=NDZ027&local_place1=6+Miles+SW+Gilby+ND&product1=Winter+Weather+Advisory

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  7. Jim..

    Southern RRV and SE MB could see 2-5 cm tonight but overall just a light snowfall for us in the RRV north of the US border. Tonight's system will be mainly affecting areas south of the border as per ND advisory area where 8-15 cm is forecast.

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  8. Tuesday night system brought/bringing generally 2-4 inch snows Grand Forks southward...Reports of 6-7 in small area near Aberdeen SD northward to Oakes ND (all southwest of Fargo). Very fine flakes.... on top of 2.5 inches of snow Sunday a nice few days worth of fresh snow. Friday is looking quite windy with a band of moderate snow moving thru nrn valley. Our national centers are forecasting 2-4 inches nrn valley and nw MN. A good warmup potentially next week for a few days... latest snow pack temp in the teens over the nrn valley and srn Manitoba so it will take some energy to warm it up to start any true melt.

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  9. Latest model runs trending towards a more northern track on Friday's system.. putting greatest snow potential well north of Winnipeg through central MB. Looks mild in the RRV Friday with patchy rain, drizzle or freezing rain, then some snow moving in Friday night as cold front pushes through with increasing north winds and falling temperatures. Perhaps 2-5 cm for the RRV by Saturday morning.

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  10. Interesting to see two different camps here with the american models (GFS, NAM) showing a more digging 500 mb system and a second sfc low developing in central MN Fri eve versus the farther north GEM and ECMWF. Our national centers are indicating 4-6 inches psbl in srn Manitoba with 3-4 northeast will be fun to see who wins.... the above is as of early thu am

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  11. Dan.. GEM is hinting at a double low structure but it's much weaker on the southern development.. even though they show a secondary vort max tracking through ND. Friday evening/night looks interesting with strong cold advection, strong winds and falling snow.. will make for very slick conditions Friday evening with a rapid freeze up after some melting Friday afternoon.

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  12. Dan

    Looks like the NAM/GFS were the winners with this one.. southern low was the dominant feature, with GEM overdeveloping the northern low.

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