Tag: Snow

After A Failed First Attempt, Winter Arrives Saturday

Brad Leave a comment

Winnipeg may have managed to dodge the snow on Wednesday, but another disturbance moving through Saturday will blanket the city in snow, then be followed up by the first winter-like cold snap of the season.

Today will be a fairly benign day in Winnipeg as the disturbance that will bring snow to the region tomorrow develops over Montana and Saskatchewan. Before that arrives, the region will see a mix of sun and cloud with temperatures climbing back to a high near -2°C and light winds.

Clouds thicken up tonight as the inverted trough1 that will bring snow to the region advances across Saskatchewan. Expect temperatures to dip to a low near -5°C early before climbing back towards around -3°C by morning with winds picking up out of the east to around 20 km/h. Some light snow may move into the Red River Valley late overnight, but if this system ends up a bit slower then the snow may hold off until Saturday morning.

NAM Forecast Precipitation valid 12Z Saturday November 4 to 06Z Sunday November 5, 2017
Moderate snow will spread into the Red River Valley Saturday morning and persist through the day

Saturday will bring snow to much of southern Manitoba as an inverted trough moves across the province. The snow will spread from southwest of northeast through the day, with the heaviest snow in the Red River Valley expected midday into the afternoon. The snow will taper off from west to east, beginning in the late afternoon over the southwest, then through the evening in the Red River Valley, and after midnight in the southeast. Between 5 and 10 cm of snow will likely accumulate across much of southern Manitoba, with the chance for localized pockets of slightly higher amounts, by the time the snow tapers off.2

RDPS Forecast 2m Temperature valid 00Z Sunday November 5, 2017
Temperatures will climb to or just above the freezing mark across muhc of south-central and southeastern Manitoba on Saturday afternoon

Aside from the snow, Saturday will bring more mild temperatures to Winnipeg with highs climbing to or just above 0°C. Winds will gradually ease through the day, but then pick up to 20 to 30 km/h out of the northwest overnight, making some blowing snow possible in open areas. Temperatures will dip down to a low near -4°C on Saturday night.

Sunday will bring mainly cloudy skies to Winnipeg, but temperatures will barely recover from the overnight low, reaching a high of just -2 or -3°C as northwesterly winds usher cooler air into the region ahead of an approaching Arctic high. Sunday night will be quite cool with lows sinking to near -13°C as skies clear out.

Long Range Outlook

In the wake of Saturday’s disturbance, cooler temperatures will flood into the Prairies as a persistent northwesterly flow aloft taps into Arctic air. Temperatures will remain well below-normal for much of next week, save for a brief reprieve in the latter half of the week when another low pressure system moves through, but then the cold temperatures surge back into the region. So bundle up and get your winter clothes out, you’ll be needing them!

Winnipeg’s seasonal daytime high is currently 3°C while the seasonal overnight low is -6°C.

  1. An inverted trough is a trough of low pressure that extends northwards from a low pressure system. ↩
  2. While model agreement is increasing, there’s still a fair amount of uncertainty with this system and we may update our snowfall forecast later today if needed. ↩

Cool and Snowy Start to November

Brad Leave a comment

November will be off to a snowy start as a clipper system tracking across North Dakota spreads snow across southern Manitoba today. In the wake of this low, an Arctic ridge will build into the Prairies and bring unseasonably cool temperatures to the region.

Light snow is on the way for Winnipeg today as snow spreads through the Red River Valley, supported by a low pressure system tracking across North Dakota. The snow will begin early this morning and persist throughout the day before tapering off later this evening. By the time snow tapers off, this system will produce generally 5-10 cm of snow along and south of the Trans-Canada Highway corridor with highest amounts near the US border decreasing northwards. The fly in the ointment, as it were, will once again be temperatures that climb up to or just above the freezing mark. The mild conditions will result in quite a bit of snow melt, however it’s likely that a few centimetres accumulate by the end of the day. That said, it won’t quite be the widespread blanketing that it would be if things were even a couple degrees cooler.

RDPS Forecast 24hr. Accumulated Snowfall w/10:1 SLR valid 09Z Thursday November 2, 2017
This system will produce 5-10cm of snow over the Red River Valley, however mild temperatures will reduce the amount of snow that actually accumulates

Aside from the snowfall, it will be a relatively pleasant day. Temperatures will climb to a high near +1°C with winds out of the east-northeast at 20 to 30 km/h. Heading into the evening, the winds will shift to the north at around 30 km/h with snow tapering off as temperatures dip to a low near -2°C under mostly cloudy skies.

Thursday will bring mostly cloudy skies to Winnipeg and area, although a few sunny breaks are possible. Temperatures will recover just barely to -1°C as a breezy northerly wind continues, marking the gradual approach of a large Arctic-sourced high pressure system. The cloud cover will break up in the evening as winds drop off, which will send temperatures plummeting to a low near -10°C as colder Arctic-sourced air arrives.

GDPS Forecast 850mb Temperature Anomaly valid 06Z Friday November 3, 2017
This forecast of 850mb temperature anomalies shows the much cooler than seasonal air mass that will be in place over Southern Manitoba on Thursday night

Winnipeg will see mixed skies on Friday with temperatures climbing back to around -3°C with light winds. Expect the cloud cover to thicken back up on Friday night in advance of the next system that will move through this weekend as lows dip down to into the -7 to -10°C before beginning to moderate towards Saturday morning.

Long Range Outlook

Saturday and Sunday will both be largely influenced by a major low pressure system tracking across the Prairies. A warm front will push through on Saturday, bringing rain and snow to the region as temperatures climb just above freezing again. There will likely be a break in the precipitation, but then a cold front will sweep through Saturday night into Sunday, bringing more snow and breezy northwesterlies as temperatures plunge well below seasonal.

NAEFS 8-14 Day Temperature Anomaly Forecast — Valid November 8-15, 2017
NAEFS 8-14 Day Temperature Anomaly Forecast — Valid November 8-15, 2017

Next week looks very cold as the jet stream plunges south, allowing Arctic air to spill southwards across the Prairies. If you haven’t already, it’s probably time to get the winter jacket and gloves out!

Winnipeg’s seasonal daytime high is currently 4°C while the seasonal overnight low is -5°C.

Cooler Weather With More Snow

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Plenty of cloud and snow is in the forecast as one low pressure system leaves only to be quickly replaced by another mid-week. Temperatures will also remain cool as a large upper trough keeps the jet stream south and allows cooler Arctic air to spill into the Prairies.

Today will bring mainly cloudy skies to the region as a low pressure system that tracked through the region on Sunday pushes off into eastern Ontario. To start off the morning, widespread flurries in place across the region will taper off as a strong northerly wind of 40-50 km/h develops. Snow will taper off by midday for many locations except for two: those in the lee of Lake Manitoba and Lake Winnipeg.

RDPS 24hr. Accumulated Snowfall in Inches at 10:1 SLR valid 00Z Tuesday October 31, 2017
At a 10:1 snow-to-liquid water ratio, which may be low for the snow coming off the lakes, models suggest close to 10 cm of snow in the lee of Lake Winnipeg and Lake Manitoba

Strong northerly winds align along the basins of each lake this morning and persist all day, and as the colder air moves into the region, bands of lake-effect snow will develop and move southwards off the lake. The areas highlighted in the area above are the most likely to see snow and significant accumulating snow. Snowfall accumulations can be difficult to forecast in these events, but indications are that as much as 10 to 20 cm may fall by the end of the day under the heaviest band of snow. The Lake Manitoba event will taper off in the early evening as a ridge of high pressure moves in and eases the winds, while Lake Winnipeg will persist longer, weakening in the evening and ending overnight.

Aside from the snow, it will be a cool day whose high near -1°C will feel closer to -8 or -9°C with the strong northerly wind. Once the ridge moves into the area in the evening, winds will taper off and temperatures will head towards a low near -8°C under mixed skies.

Tuesday will bring benign weather to the region with mixed skies and temperatures climbing back to a high near -1°C. Winds will pick up out of the south through the morning hours, strengthening to 25 to 35 km/h for the afternoon hours. By evening, more cloud will be spreading across southern Manitoba in advance of the next low pressure system as it tracks across Saskatchewan. The cloud will keep temperatures a bit warmer overnight with lows of around -3°C. Winds will continue out of the southeast at around 20 to 30 km/h.

Wednesday will see the low and its associated area of snow move through the province. In the Red River Valley, snow will begin early in the morning and persist into the evening. As is the case with these early season events, the biggest challenge with this system will be the near-zero temperatures with daytime highs climbing to around 0 or +1°C and how that will affect how much snow accumulates versus melts. The expected snowfall is around 4 to 8 cm, but the actual accumulated amount will be less than that, with roadways likely ending up with a slushy centimetre or two by the end of the day, and grassy areas seeing closer to, but not the full, amount that falls.

Fortunately, winds will taper off in the morning, so visibilities will be as good as they can be with the snow falling. The wind will pick up out of the north in the afternoon into the 20 to 30 km/h range. The cloud cover will likely remain through the night with the potential for a bit of lake-enhanced/effect snow coming off of Lake Manitoba and Winnipeg. Temperatures will dip to a low near -6°C.

The only real uncertainty with this system is how far south it will end up going, and whether or not it will end up too far south to impact our region. The general consensus is that Winnipeg and the Red River Valley will see snow, but we’ll be keeping an eye on how it develops just in case.

Long Range

The remainder of the week doesn’t look much better; Thursday will see any remaining flurries taper off with a continued north wind that makes the high near -1°C feel rather cool. Temperatures will then dip down to the low minus single digits on Thursday night and rebound to just -2 or -3°C on Friday under mostly cloudy skies. Another cold night on Friday night will lead into highs returning to the freezing mark on the weekend, but that’s due to the approach of a mother system that will bring another wintery mix to the region late Saturday into Sunday.

NAEFS 8-14 Day Temperature Anomaly Forecast — Valid November 6-13, 2017
NAEFS 8-14 Day Temperature Anomaly Forecast — Valid November 6-13, 2017

Once that passes by, a significant chill will descend across the Prairies, bringing below-normal temperatures for an extended period, alongside the potential for more snowy weather.

Winnipeg’s seasonal daytime high is currently 4°C while the seasonal overnight low is -5°C.

Cool Conditions Give Way to Milder, Unsettled Weather

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Winnipeg will be offered a reprieve from yesterday’s snow and harsh wind as with temperatures set to rebound towards seasonal values over the next couple days. The region will see increasing cloud through the weekend, though, as another low pressure system will bring some light snow and rain to the province Saturday night into Sunday.

The sun will be back today in WInnipeg as a ridge of high pressure building southwards clears out the remaining clouds from yesterday’s storm system. Temperatures will slowly climb back above freezing or a high near +2°C this afternoon. While that’s a bit below-seasonal, the absence of any wind will be a welcome change. Skies will remain clear tonight, but the ridge of high pressure in place will send temperatures well below-seasonal tonight with lows of -6 to -10°C through the Red River Valley and southern Interlake.

Temperatures will fall well below zero across much of southern Manitoba tonight

Saturday will see seasonably cool conditions in Winnipeg for the last Blue Bomber’s regular season home game. Winnipeg will see a mix of sun and cloud as warmer air spreads eastwards across the Prairies ahead of a low pressure system sliding southeastwards from Yellowknife, NWT. Temperatures will reach a high near 3°C with light winds.

Skies will cloud over late in the afternoon or early Saturday evening with a mix of snow and rain moving into the Red River Valley from the north. As the evening progresses there will be a continued chance for showers.1 Temperatures will dip to a low near +1°C with winds increasing out of the south to 20-30 km/h.

A low pressure system dropping southeastwards from the Northwest Territories will spread rain and snow across Manitoba on Saturday night

Sunday will start with a cold front swinging through the Red River Valley, bringing with it some morning showers and shifting winds to the northwest at 30-40 km/h. There will be a slight chance of showers through the remainder of the day after the cold front passes, but it appears much of the precipitation associated with this system will remain further north and east of Winnipeg, along a the track of the low moving through the province: from Swan River southeastwards through the central Interlake and into southeastern Manitoba. Temperatures will reach a high near 6°C.

Sunday night will continue to be overcast with an increasing chance of rain changing to snow through the night as the precipitation that is north of the Red River Valley slumps southwards. Temperatures will dip to a low near -1°C with winds remaining out of the north at 30-40 km/h.

Long Range Outlook

Monday will likely bring some morning snow giving way to cloudy skies and a high near freezing with breezy north winds continuing. It looks quite likely that lake-effect snow will develop off of Lake Manitoba and Lake Winnipeg, potentially bringing accumulating snow to the regular places: near Portage la Prairie and southwards along the western escarpment, and south of Lake Winnipeg towards Beausejour. Of course, exactly where sees these bands of snow will depend significantly on the exact wind direction, so it’s a bit early to say much of whether or not Winnipeg will be impacted.

The remainder of the week looks cool and will bring several chances for flurries as multiple disturbances move through.

Winnipeg’s seasonal daytime high is currently 6°C while the seasonal overnight low is -4°C.

  1. Snow will only be likely in the early evening; increasing amounts of warm air aloft combined with surface temperatures above zero should provide enough warmth to favour rain. ↩