Projected snowfall accumulations Friday night into Sunday
(GEM model left, NAM model right)
|GEM snowfall accumulations |
Fri evening to Sunday morning
orange area is 25cm+
|NAM snowfall accumulations |
Fri evening to Sunday
orange area is 25cm+
Regardless of the total amount of snow that falls, residents should be prepared for a prolonged period of snowy weather over southern MB beginning tonight, lasting through Saturday into Sunday morning, and gradually tapering off later Sunday. Road conditions will deteriorate as the storm progresses, especially Saturday and Saturday night when the bulk of the snow is expected across southern MB. Be prepared for much slower travel times and possible road closures. (In fact, I wouldn't be surprised to see the TransCanada closing tomorrow from Winnipeg to the Saskatchewan border) Northerly winds of 30 to 50 km/h will accompany the storm with reduced visibility at times in snow and blowing snow. Improving conditions are expected later Sunday as the storm pulls off. Note that this storm will also be affecting neighbouring southern Saskatchewan, North Dakota, NW Minnesota, and NW Ontario so keep that in mind if you have travel plans to those areas this weekend. For MB highway conditions and any road closures, visit Manitoba Highways website.
Radar Viewer from A Weather Moment, which is displaying radar echoes in SNOW mode. Note that radar imagery on the Weatheroffice website is still on RAIN rates, and will significantly underplay snow intensities. Radar imagery on Weatheroffice is fixed on rain rates nationally until Dec 1st when it switches over to snow rates.
Models are showing quite the mix of precip in the Sprague area, including 6 or 7 mm of freezing rain (and temps staying below 0). I hope MB Hydro and the road crews are prepared, especially with no cell service in that area.ReplyDelete
Rob What are the estimates of SOG Sunday eve at your site?ReplyDelete
Is it cold enough for significant drifting?
Even at this late stage, I'm still not sure how much snow Winnipeg will get. I think we have a good shot at 25 cm by Sunday evening, with models hinting that the heaviest snow for Winnipeg may not be until Saturday night. What I'm thinking is that the heaviest area of snow will be falling mainly west of Winnipeg during the day Saturday, then the heavier snow shifts over us later Saturday into Saturday night and early Sunday as the upper low crosses by, and we get colder temperatures. Overall, it still looks like a good 20-25 cm for the city, possibly 30-35 cm if any heavy bands go over us.ReplyDelete
Dramatic change in track of low from GFS from 12Z run.. with 993 mb surface low getting as far NW as Fergus Falls MN.. GGEM even further NW with low over Thief River Falls. RGEM similar with NAM a more progressive outlier.ReplyDelete
Will have to watch closely in the 18Z and 00Z runs to see if trends continue. If so, main snow band and frontogenesis will set up off to our NW with dry slot and warmer air aloft 'dumbelling' around northern side of low.. giving us more like light freezing drizzle mixed with sleet.
We may have to chalk one up to climatological trends and past analogues versus vacillating and clumsy deterministic model runs in anticipating the track of the storm. Looking more like that 2008 system and scenario 3 if trends continue.. we'll see.
Latest NAM shows bigger NW push of ice pellets towards RRV Saturday, possibly into Winnipeg. That would reduce our amounts somewhat here during the day before heavier snow moves in Saturday night as colder temperatures aloft move in.ReplyDelete
Very challenging forecast for Winnipeg as models have been pushing the track of this storm back and forth almost daily. We went from what looked like a Scenario 2 early on in the week to a scenario 1 the past couple of days, to a scenario 3 now.
It should be noted that the NAM is the most aggressive model so far with the NW extent to the mixed precip into the RRV and YWG.. most of the other models keep mixed precip over SE MB. Something else to keep an eye on..ReplyDelete
Yeah the NAM is actually further east with the low in Minnesota than other models, but 18Z run shows the low retrograding west towards the Manitoba border - implying a more intense upper circulation winding up and pulling the low back. That would also allow for more warm air to back in aloft..ReplyDelete
Goodness, GFS's 45 cm of snow and 12 mm of ice pellets is astronomical. Hard to believe that would happen, but who knows at this point...ReplyDelete
Too bad the storm had to be tomorrow when it comes to the record books. The old daily snowfall record tomorrow is 31 cm in 1919, so this event may not even break a record... We'll see though, but that record will be hard to beat.ReplyDelete
The sudden northwest trends need to be considered. GFS continues with the mainly snow idea and lots of it. GFS has been the most consistent with the track it seems. If the northwest trends continue with the OOZ runs, though, it's going to cause some headaches for forecasters. Tough call.ReplyDelete
Rob, what do you really think is going happen in Winnipeg? all snow or mixed precip then heavier snow with slightly lesser amounts.ReplyDelete
Really wish I could be more definite about snowfall for Winnipeg, but it's still a tough call. The big question is how far west low will track in Minnesota. That will determine where the snow/mixed precip line ends up over southern MB, and where the bulk of the heaviest snow falls (which will be west of that line). If the trend of the low being further NW continues, then I think Winnipeg will see snow changing to ice pellets Saturday afternoon and continuing into the evening before changing back to snow Saturday night into Sunday. If we don't change to ice pellets and we stay as all snow, then we could see some pretty hefty totals here. Either way, I think the heaviest snow will be setting up to the west and north of Winnipeg deeper in the colder air.ReplyDelete
Based on current info then, this is what could transpire in Winnipeg..
Light snow develops overnight and picks up intensity in the morning, with 5-10 cm by mid afternoon. Snow will then mix with or change to ice pellets Saturday afternoon and evening, with additional accumulations of 2-5 cm through the evening. Ice pellets change back to snow Saturday night and continues into Sunday, with another 5-10 cm of snow before it tapers off Sunday afternoon or evening. In total, we get about 15-20 cm of snow from the storm. If we DON'T switch to ice pellets tomorrow, then we're looking at 30 cm total.
Will wait on updated guidance tonight and see how thermal fields and precip areas are setting up before I update forecast.
I agree with Rob here.... to me looks like the warm air aloft will indeed get pulled back a bit farther northwest than thought 24 hrs ago...so would expect sleet back to winnipeg and significant freezing rain somewhere in southeast MB into northeast ND.... we have drizzle at my house now 31.2 Think we will warm up to just above 32F saturday and be more liquid here during the day now.ReplyDelete
Wow...models still having difficulty handing this system even the day before the main event...Having been outdoors today and tonight it would be hard to imagine the word warmer air but that's at the surface though.. Pretty darn chilly today with that brisk northeast wind. But I agree, if we get a extended period of ice pellets there's now way we get 30CM of snow. Personally i still think the amounst of snow expected are too high especially given that we are not known for these big type of snowfall here in Southern Manitoba. GFS giving 50 CM really is rather ridiculous when we all know that ain't gonna happen.ReplyDelete
Looks like we won't really know how it unfolds until it does.
As far the forecast for snow beginning this evening..don't really see that happening given it's not even snowing in the Brandon area yet.
Rob, when do you anticipate the snow to arrive here in Winnipeg?
This comment has been removed by the author.ReplyDelete
Actually Anon, the 42cm is probable given there is a time frame on Saturday when we get 20cm and then saturday night in which the snow stops and we recieve ice pellets until Early Sunday where we start getting more snow 20cm as the low moves off. Likely, at the moment.ReplyDelete
Mike, the ice pellets would actually be earlier Saturday like Saturday afternoon into the evening then back to snow Saturday night according to current indications and from what Rob's indicating.ReplyDelete
Well The Gfs's timing must be off a little, I am not discounting it's possible snowfall amounts. It may be closer to 35cm at the most, we will have to wait and see. Things could change in the meantime.ReplyDelete
I certainly am also very cautious when it comes to discounting these snowfall totals because i agree it's certainly possible..this storm is pretty intense and very energetic but not sure we'll get 35CM+ on top of the GFS forecasted 11 mm of ice pellets. I'm agree with what Rob mentioned, better chance for 30CM if it stays all snow.ReplyDelete
Mike - The GFS is a Global model, more typically used as a 'heads up' for long-range forecasting (even the Americans acknowledge that it isn't a great model). Our media tends to use that model as well in their American WSI presentation software. It still has it's uses in the short-range, but shouldn't be treated as gospel.ReplyDelete
The 00Z GEM-REG shows 15 cm, the 00Z NAM shows 17 cm. 15-20 cm still sounds good to me.ReplyDelete
Darn... I was hoping for 30cm, 20cm is a little low for me but sounds agreeable if we are about to get ice pellets. Any chance it may change over the next 12 to 18 hours?ReplyDelete
Anonymous (from 9:07 pm post)ReplyDelete
Re: Start time of snow in Winnipeg
Radar is starting to fill in nicely over SW MB this evening, but I agree that it will still be a few hours before it moves into Winnipeg. Models are indicating sometime between 2-6 am which looks reasonable based on current radar trends.
BTW.. 100 entries on Rob's Obs snow poll, by far the most responses on a poll question I've ever received. Lots of interest out there. Leading pick is 15-20 cm, with 20-25 cm not far behind. Poll average is 17 cm. Thanks for all the responses.. let's see who'll get bragging rights! (For the record, I picked 20-25 cm)
I guess I will also look at the NAM now it terms of it's data, wasn't sure which model is more accurate in the short term. Now I know, thank's guys!ReplyDelete
Do you personally think GFS is a poor model and that it's overdoing the snowfall totals like garth mentioned in high 9:48 post?
Yeah, heavier snow definately moving in nicely in Southwest Manitoba...Should be snowing in Brandon very soonReplyDelete
Looks like the heaviest snow will stay west and over into the central Interlake, scenario 3, but perhaps with a few more cm of snow.ReplyDelete
That's it for me tonight.. going to watch some TV and then hit the sack. Will check back in the morning and see how things are developing. Hopefully things are nice and white when I get up!ReplyDelete
Mike- I'm perhaps somewhat biased against the GFS after seeing it perform poorly numerous times this year, at least over southern MB. It's a good model overall (but less accurate than the ECMWF many say). But it is still a global model, not regional, so best suited for long-range forecasting (in my uneducated opinion).ReplyDelete
I agree with you Garth NAM handles better, I am still learning as an amatuer though So I will likely gain experience as the years go on. 25cm is my best bet for totals, that is of course only likely if we dont get ice or sleet.ReplyDelete
Guys I have a new post up on my blog, feel free to ask questions I admit I'm not as good as Rob is. Click my name to get access.ReplyDelete
If this snow is suppose to come to southern Manitoba approximately what time will it be here? And how fast is this storm moving?ReplyDelete
If you are asking me the question, it is looking more and more likely that the snow which will be fairly light in intensity will get here later than first thought. Estimates are around from 12am in Western Manitoba and 1 to 2am in the Red River Valley and points East. I think that the heavier snow will have a tough getting into the Winnipeg region, and may not get here until the morning hours to afternoon hours Tomorrow. There could be either snow or sleet tomorrow. Will have to find out.
As for the speed of the system, it has been moving fairly fast over the past 24 hours and it should be somewhere in Northeast north Dakota or Minnesota tomorrow evening. It's Current Position is in Colorado edging into NW North Dakota likely moving East at 30 knots. Currently setting up a nice Snowband in and around SW Manitoba creeping ever so close to the city of winnipeg.
As for Snowfall tonight looking like 5 to 10cm at the most by 11am tomorrow. That is what the NAM is pointing towards at the moment.
Well my turn to head to bed and take a rest for the night. Have a good one guys! I hope I answered your question....
Radar filling in very nicely...snow spreading eastward as of 12:30 am with snow now falling just to the southwest of the city. heavier snow falling in SW MB. Here it comes, folks!!!!ReplyDelete
Snow update: According to latest radar at 1:15 AM, snow now just along south perimeter. Pretty decent band of snow by the looks of things. I say the ground should be white by wake up time Saturday morning. Heavy snow pretty much all over SW MB now.ReplyDelete
Quick update: snow now just entering the city limits from the southwest according to the latest radar image at 1:35 AM. Almost upon us now this storm, folks!!!ReplyDelete
Update: Well here it is folks, the snow has arrived in the city and has just begun at 2:00 AM. Not as impressive a band of snow moving into the city compared to earlier at least according to the latest radar image at 2:05 AM, however definately alot more snow to come.ReplyDelete
Well, time for me to hit the sack as well. We'll see how this are in the morning.
**correction** Meant to say we'll see how things are in the morning.ReplyDelete
From yesterday morning:ReplyDelete
So when's the snow going to start? Numerous models suggest after midnight. CBC says this evening. CTV says this afternoon already (according to their website).
I'll stick with the model consensus of around 1-2 AM.
10:29 AM, November 09, 2012
Looks like the models at least had the timing correct. All human sources (EC, CBC, CTV) were off by at least 5 hours, even on their 5pm weather forecast).
I have been looking at all the radars and just wondering if this storm is taking a little more northerly route than expected.ReplyDelete
2 cm of snow at my place as of 7:30 am. Snowing lightly, but steady. Snow appears to have a "pellety" look to it rather than big flakes, which may be an indication that warmer air aloft is moving in. We'll see. Radar shows heaviest area of snow setting up north and west of Winnipeg, lighter amounts south and east.
Latest model consensus shows about 10 cm for Winnipeg today, with the bulk of our snowfall possibly occurring tonight into Sunday morning with another 10-20 cm possible.
Will be updating amounts through the storm.. and tweeting to #mbstorm. Would appreciate any reports from wherever you are. Thanks!
Yeah...have had 2 CM as my place in Windsork Park as well since 7:30 this morning.
I was looking at the radar moments ago and wondering could we be getting a break from the snow for awhile because it appears the snow around us particularly south and somewhat southwest seems to be diminishing?
Definately looks like Ice Pellets here in the Windsor park area now.ReplyDelete
With the luck we've had with big storms such as this one in the last few years, wouldn't be surprising.ReplyDelete
It's back to snow now in the Windsor Park area..agree with Rob it's looks for pellety than big flakes.ReplyDelete
Rob, do you think that 30 CM is still a possibility for Winnipeg?
**correction** looks more pellety than big flakesReplyDelete
Heaviest snow today will be occurring well north and west of Winnipeg, with lighter snow over RRV and areas SE. But we will see snow here through the day with heavier bursts now and then.. along with some ice pellets mixing in. Looks like the best chance for heavier snow for Winnipeg will be tonight into Sunday morning, as we get colder aloft and a second wave of precipitation moves around the intensifying low to our east. So perhaps 5-10 cm for Winnipeg today.. and a burst of 10-15 cm tonight into Sunday morning. 30 cm is a stretch for Winnipeg, but it could happen if that heavy burst nails us overnight. It might be one of those cases where you go to bed thinking the storm wasn't that bad, and then wake up the next morning saying.. Whoa! Where did all that snow come from?!ReplyDelete
Whatever the case, heaviest snowfall from this storm system will almost certainly be over western MB and the interlake areas where 30-40 cm storm totals not out of the question.
Looking more like snow here Windsor Park now with some slightly bigger flakes falling.ReplyDelete
Either way, even if we don't get quite 30 CM..it will still be a fairly decent storm. Snowing all the way now here in Windsor Park and a little more heavier as well.ReplyDelete
I just added Snow Depth to the NAM graphs on SpotWx (scroll to the last graph). http://spotwx.comReplyDelete
The 12Z model is assuming we had 7cm already at 6am (we only had around 2cm), and is forecasting about 18cm total. So subtract the extra 5cm which leaves 13 cm snow depth once this storm is over.
The snow fall is forecast at 13.5 cm (assuming a 10:1 snow/liquid ratio) so it makes sense.
Not saying I agree with the model, but it's there if you want to look.
here inwinnipeg its really coming down maybe we will get 20 CM.ReplyDelete
I'm hearing roads in some place are in bad condition in the city as in slippery.ReplyDelete
Little to no snow falling here in Windsork Park right now, but definately more coming. Stay safe on those roads and drive carefully, folks.
Updated post up..ReplyDelete