A progressive weather pattern shaping up will bring more variable weather conditions to southern MB over the next week, with a roller coaster pattern of temperature swings. After another frigid cold snap this week, it looks like we'll have a significant, albeit brief, warmup for Winnipeg and southern MB on Saturday as a low pressure system crosses just north of Winnipeg through the interlake area. This system will bring in some snow, with 2 to 5 cm possible generally south of the TransCanada, and higher amounts of 5 to 10 cm north of Winnipeg through the Interlake areas. Gusty south winds accompanying the snow will also produce blowing and drifting snow especially through the Red River valley with poor visibilities at times. As a result, be prepared for poor travelling conditions Saturday.
As for temperatures.. don't let that forecast high of 0C for Saturday fool you. Gusty southerly winds will make it feel considerably colder, especially in the morning when temperatures will still be in the minus teens, and snow and blowing snow will make it blustery. Temperatures will gradually moderate in the afternoon reaching minus 5 or so by late day. In the evening, winds will shift into the northwest, and we will briefly tap some milder air from the west with temperatures climbing towards the freezing mark Saturday evening, before cooling off again Saturday night. Temperatures are expected to drop to below normal values again for Sunday and Monday, but not as cold as the current cold snap. Another Alberta clipper is expected to bring moderating temperatures and some snowfall on Tuesday, before a trend towards milder temperatures (near to above normal) moves in by the end of the week. A roller coaster week coming up!
Rob I can't seem to use your 'Forecasts, Radar, etc.... the row of drop downs work, but they don't 'activate'. Am I missing something?
ReplyDeleteLatest ETA runs show the low and precipitation shifting farther south. The ensemble forecast also shows the area farther south than the GFS. The GEM also agrees with this, although I think it may be exaggerating the precipitation amounts a bit. It looks fairly similar to the Wednesday one, very small, but intense. All the warm air surging up from the South should make a difference. The high for Saturday on my forecast is -2, but I mentioned how local areas might reach 0 for a couple hours.
ReplyDeleteAnonymous..
ReplyDeleteDrop down links seem to work fine for me.. perhaps a local problem? Also, note that a link won't activate again once it's activated and it still is displayed in the drop down window. You need to go to another link, then back to the original to activate it again... Kind of a pain.. I'm looking into a new drop down menu to get around this.
Looks like we hit almost -37 this morning, with the wind chill that was -44.
ReplyDeleteTomorrow looks like a chance of snowfall for south-central and south-eastern Manitoba, as well as the interlake.
looks like a very good setup for some freezing rain tomorrow!!!
ReplyDeleteAll the warm air aloft overrunning some still chilly air at the surface!!!
Oh boy and all that very heavy wet snow tomorrow with freezing rain will be a travel nightmare even in the city!!!
The coldest nite of the winter for the Winnipeg region in general. Areas north of highway 1 and east of highway 12, including the SW outskirts of Winnipeg were around -34 to -35 C. Even colder in SE Manitoba where there is a bit more terrain for cold air to settle.
ReplyDeleteUpper clouds advecting over top of the arctic ridge kept areas just to our southwest considerably warmer. These upper clouds moving in with the jet are a big potential source of forecast error in these situations.
Seems more important to look at the upper flow in these cases to see where the moisture aloft will advect. A zonal flow... even with a colder air mass in place (like a few weeks ago) seems to allow any upper clouds to reach well into Manitoba instead of being shunted into the dakotas.
A lot of warm air over Alberta with this system.. up to +6C in Edmonton this afternoon, even +6C as far north as Peace River! Temperatures up to -5C now in Saskatoon after a morning low of -21c. Rising temperatures tonight a given over southern MB.. question is.. how high will they go tomorrow?! With the main low forecast to track north of Winnipeg, we should be able to tap some of that mild, albeit occluding air, from the west once our winds shift into the west Saturday afternoon. Areas southwest of Winnipeg may climb above zero Saturday afternoon, while Winnipeg still has a shot at that freezing mark. Will be interesting to see what happens.
ReplyDeletePrecipitation is another issue. Soundings support potential for freezing rain over SW MB Saturday morning, possibly ice pellets into Winnipeg. Bulk of snow expected to remain mainly north of low track through the Interlake areas into NW Ontario, with 10 cm possible. Maybe 5 cm or so for Winnipeg. Tough call.. lots of variables and uncertainty to get everything right.
According to the ensemble forecast, the heaviest precipitation tomorrow will be a swath from Brandon, to Winnipeg , and over into the Kenora area. With that area extending around 75km north and south of that line. The chance for the largest accumulations are through South-Eastern Manitoba with the Whiteshell having the best chance.
ReplyDeleteI think that the area of precip will move farther South than forecast, the ETA, GEM, and Ensemble all indicate this. Saturday should be interesting, and WARM!
Yes, this is a tricky system. It looks like there will be a short period of time where freezing rain could fall, but there will be some dry air aloft at that time, so amounts should be small. By the time the atmosphere saturates, the air should be cold enough for mostly snow, although there could be ice pellets (a.k.a. sleet) and snow pellets during the transition to all snow. There may be some snow showers Sunday due to residual mositure and some instability. The lifted index, accoring to model data, should be around 6.5 Sunday morning. That would allow for light rain showers in the summer, so it can create light snow showers now. It will be interesting to see how that plays out.
ReplyDeletePatchy area of freezing rain over central SK around Saskatoon/Prince Albert area should move southeastward over southwest MB overnight. This area of precipitation may move into the Winnipeg area as some ice pellets or freezing rain by morning as temperatures aloft rise above zero ..although we could also see a quick burst of heavy snow for a couple of hours in the morning. Otherwise, not much in the way of widespread snow with this system. Still a tricky forecast..
ReplyDeleteModels are now in agreement that there will be two distinct snow events. One will be today (Sat) with the front, and the other will be tomorrow with convective shower activity.
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