Tag: wintery mix

Manitoba

Winter Storm to Bring Blizzard Conditions Throughout Thanksgiving Weekend…

A strengthening Colorado Low will bring a long-duration, widespread winter storm to portions of the Upper Midwest in the United States before moving into Manitoba and Northwestern Ontario with blizzard and ice storm conditions.

A band of light to moderate snow will cross Southern and Central Manitoba along a cold front throughout the early morning on Thursday bringing a widespread 2-5cm, locally 10cm of snow. Into the late morning and early afternoon, conditions will begin to deteriorate as a Colorado Low begins to push north towards the region.

Widespread snow is expected across Southern and Central Manitoba extending from the Saskatchewan border into Far Northwestern Ontario. Across the Southeastern Manitoba into Northwestern Ontario, heavy rain will begin to soak the already saturated ground. This will also begin the long-duration ice event which is expected along the Ontario-Manitoba border, east of Winnipeg, extending northeast towards Red Lake and Weagamow Lake in Northwestern Ontario.

The exact location of the system is yet to be determined. Most global forecast models are consistent with the system moving over the Lake of the Woods area, although, a slight shift in the track will make a major change in the forecast in terms of snowfall/rainfall locations, more significantly, the location of the significant ice.

SNOWFALL & BLIZZARD CONDITIONS – SOUTHERN REGIONS

Accumulations from the winter storm will vary greatly throughout Southern Manitoba with the heaviest accumulations throughout the higher terrain. Current guidance suggests snowfall totals will be highest between 30 and 50cm, locally higher towards 65cm+, in the extreme southern portion of Manitoba throughout the Red River Valley into the Darlingford Moraine region. This area has been highlighted with the extent of dark pink in the forecast map. Isolated totals near 70cm may be possible. Snowfall warnings are in effect for portions of this region.

Throughout this region, widespread winds between 60-80km/h are likely to cause significant blowing snow and possibly blizzard conditions. Whether blizzard warnings are issued or not, significant impacts on travel are likely across much of the major highways in the southern portion of the province. Highways such as 1 (Trans Canada Hwy.), 2, 3, 5, 23 and 75 should be avoided throughout the weekend.

The criteria for a blizzard classification and blizzard warning in Canada follow the 4-4-4 rule: 40km/h winds or greater causing widespread reductions in the visibility to 400 meters or less for at least 4 hours. A full list of alert criteria can be found here.

Extending inland towards Lake Manitoba, including Portage la Prairie, snowfall totals will be less in the 20-40cm range although local totals between 40-60cm are possible. The extent of this region can be seen in pink. This region also includes Boissevain to the west and Winkler/Altona to the east. This region continues in a swath between Lake Manitoba and Lake Winnipeg, extending just east of the lake as well, including Bloodvein. This region is less likely to see the locally higher totals. Snowfall ratios in this region will likely peak around 10:1 (10 inches of snow for 1 inch of water).

Extending out in all direction, snowfall totals are likely to decrease. This is seen in the dark blue shade on the map. Towards the west of Lake Manitoba, snowfall totals between 10-20cm are likely. There was some discussion within the team as to whether or not we should extend this region to the west of Northern Lake Winnipeg, although, we have went against this due to the expected location and size of the system. This remains a possible option, but, less likely at this time. Between Southern Lake Winnipegosis and Lake Winnipeg, 10-20cm of snow is also possible. Towards the east, including Winnipeg, as well as areas east of Lake Winnipeg to the Ontario border, snowfall totals between 10-20cm are likely throughout the weekend with local totals towards 30cm. Finally, areas northeast of Lake Winnipeg through the Poplar region towards the God’s Lake region will also see between 10-20cm of snow with an increased risk of 20-30cm.

Towards the west into Saskatchewan, a brief period of snow is likely to bring generally 5cm of snow to the region. Further into Manitoba, 5-10cm is expected from the ‘after side’ of this system. In Ontario and Southeastern Manitoba, 5-10cm is likely with most, if not all, the snow remaining melt-on-contact due to the expected heavy rainfall throughout the system. Towards Lake Superior, snowfall totals will be localized to 5cm with limited to no visible accumulations likely.


Projected snowfall totals between Thursday, October 10th to Sunday, October 13th

SNOWFALL & BLIZZARD CONDITIONS – NORTHERN REGIONS

Accumulations from the winter storm will be significant along the Manitoba/Ontario border. The heaviest accumulations will occur in the pink region. This region extends from between Poplar Park Reserve in Manitoba and Opasquia Park in Ontario along the border to Sturgeon Lake in Ontario. Snowfall totals between 25-45cm are likely with local amounts approaching or surpassing 50cm. Outside of this region, a widespread 10-20cm, locally 25cm is likely within the dark blue region. This extends from Lake Winnipeg through to Sandy Lake and Sachigo Lake in Ontario towards Hudson Bay. with the heaviest accumulations throughout the higher terrain. A winter storm warning is in effect for portions of this region.

In the light blue region, which extends from Hudson Bay through to Lake Winnipeg and Big Trout Lake, Ontario, snowfall totals between 5-10cm are possible. Local totals towards 15cm are possible into Manitoba, although, current guidance suggests this is unlikely.


Projected snowfall totals between Thursday, October 10th to Sunday, October 13th

ICE STORM

Across Southeastern Manitoba, southeast of Winnipeg, extending into Northwestern Ontario along the Manitoba/Ontario border, a long-duration ice storm is increasingly likely.

As temperatures near 0 C throughout the long-duration of the winter storm, freezing rain and ice pellets will be a large concern along the border of the provinces towards the south. With the system expected to track of Lake of the Woods, heavy rain is likely across portions of Southeastern Manitoba (Buffalo Point westward) and much of Northwestern Ontario. A thin band of moderate to heavy freezing rain is likely to remain stationary for multiple hours.

Extending from the Vita/Marchand area in Manitoba through the Ontario border into the Red Lake and MacDowell Lake areas, heavy freezing rain between 15-30mm of ice is possible. In a tight gradient outside of this region, the freezing rain totals will quickly drop off in a thin 5-15mm ice range followed by a large 2-5mm ice range. This larger area extends from Hudson Bay through Big Trout Lake into the Whiteshell Provincial Park area in Manitoba. The attached map highlights the possibly affected areas, but due to the tight gradient, we have not added totals onto the map.

Widespread wind gusts between 40-60km/h, locally higher towards Southern Manitoba will likely result in widespread power outages in the affected communities. Highways such as 1 /17 (Trans Canada Hwy.), 44, 105, 307, 596, 658 should be avoided throughout the weekend.


Projected freezing rain totals between Wednesday (pm), October 9th to Sunday, October 13th

RAINFALL

Across Northwestern Ontario and Southeastern Manitoba, heavy rain will bring a wide swath of 40-70mm to the region. Local totals between 70-90mm will be possible in the strongest bands in the system. Rainfall warnings have been issued for these regions as there are numerous communities already dealing with flooding throughout the area.

You can continue to monitor weather alerts issued by Environment Canada from their website: https://weather.gc.ca/warnings/index_e.html

Ontario

Colorado Low Threatens Snow, Heavy Rain & Strong Winds…

Don’t let the calendar fool you – a bitter sweet transition to spring is expected. The final two weeks of winter will feature drastic temperature swings and at least one notable storm system this weekend.

An area of low-pressure will form lee of the Rockies in Colorado Friday. Deepening as it tracks northeastwards through the United States towards the Great Lakes Region Saturday evening.

Key Details:
15-25mm of rain across deep Southwestern Ontario & North of Lake Erie. Rain combined with snow-melt may lead to localized flooding.
10-20cm of snow for Northern Ontario. Heaviest snow falling East of Lake Superior & across the Nickel Belt.
Strong to damaging wind gusts for Southwestern & Central Ontario.
A surge of warm air in Southern Ontario precedes wrap around strong winds & snow

*Click image to toggle zoom.

SNOW FOR NORTHERN ONTARIO

Like many of the storms this season, this system will feature appreciable snow across Northern Ontario. A large swath of 10-15cm is forecast for Wawa, Timmins and Sudbury areas. Local amounts may approach 20cm.

MESSY WINDSTORM FOR SOUTHERN ONTARIO

First and foremost, this is a messy system for Southern Ontario. Precipitation will move into Windsor in deep Southwestern Ontario around 6pm Saturday. Progressing Northeastwards across Southern Ontario during the evening and overnight. Main concern for along the Lake Erie shoreline will be heavy downpours combined with warmer temperatures, snow melt, and runoff. Minor flooding is possible; stretching into the GTA. Be sure to monitor any statements from your local conservation authority, as we progress through the weekend.

Strong to damaging easterly winds will develop ahead of the storm Saturday evening & overnight. The strongest wind gusts are expected East of Lake Huron. Including Goderich, where peak winds could exceed 100km/h late Saturday evening & overnight. The rest of Southern Ontario will have to contend with strong easterly winds gusting 60-90km/h through the overnight into Sunday morning. Once again, winds will strengthen out of the West Sunday, with the passage of a cold front. Frequent gusts between 50-70km/h is expected.

Considering temperatures will be teetering around the freezing mark, precipitation may begin as snow, freezing rain or ice pellets. Especially, South of Georgian Bay where elevation and heavy precipitation rates will aide in keeping temperatures below freezing for a longer duration. For Eastern Ontario, this system will bring more wet snow than rain. Refer to our forecast map for further details.

New Brunswick

Strongest Low in Decades Zeros in on the Great…

Our forecasting team is vigilantly monitoring a powerful low-pressure system expected to form North of the Texas Panhandle late this evening. The upper-level disturbance originating out of California, will coincide with a favorable setup for an explosive storm development. Read more about Panhandle Hooks’ here.

Did you know? It was an infamous Panhandle Hook which sank the SS Edmund Fitzgerald on November 10th, 1975.

This storm will feature strong winds, blizzard conditions, heavy rainfall, thunderstorms, and shifting ice-conditions across the Great Lakes. Almost everyone in Eastern Canada will feel the effects of this powerful storm. Read more to gain insight on how this storm may impact you.

BLOCKBUSTER BLIZZARD EAST OF LAKE SUPERIOR

Our forecast team is closely monitoring a soon-to-be rapidly strengthening Panhandle Hook, sagging into the Texas Panhandle. Gathering abundant gulf moisture before trekking towards the Upper Great Lakes. The storm will experience the most intensification while tracking Northeastwards through the Upper Midwest (United States), towards Lake Superior & Northern Ontario. Coinciding with an expanding strong to damaging wind field.

Confidence is considerable for a high-impact Low for regions N and NE of Lake Superior with likely 30cm or more of blowing snow contingent with 60km/h+ wind gusts. The heaviest snowfall will likely be 30-40km inland from the immediate Lake Superior shoreline. This is bad news (or good new depending on your prerogative), when considering how much snow has already fallen across this region. Some are running out of places to even put the snow.

The fiercest winds will not correspond with the heaviest snowfall rates. Still, inland locales such as Timmins & Kapuskasing will still have to contend with extensive blowing & drifting snow. Especially, once the low tracks into Quebec, with colder air and stronger gusts arriving on the backside of the low.

There will be a line of mixing of wintry precipitation likely from Sault Ste. Marie to Sudbury to the QC border. Including a brief period of ice pellets and rain-showers.

WIDESPREAD DAMAGING WINDS ACROSS SOUTHERN ONTARIO

Temperatures will begin to surge above freezing across Southwestern Ontario, as early as, late Saturday evening. Double-digit temperatures & strong Southwesterly winds will advance throughout the Southern half of the Province throughout the morning & afternoon. Rain-showers and even a risk of elevated thunderstorms is expected. Proceeded by, a sharp cold front & plummeting temperatures.

We anticipate extensive blowing snow and poor-visibility East of Lake Huron late Sunday evening through Monday. Avoid all unnecessary travel in the red highlighted area on our wind impact map.

The supportive track and strength of the low will herald in a significant damaging wind threat across Southern Ontario. The strongest winds could peak as high as hurricane force (120km/h), along the Northeast shore of Lake Erie. We anticipate wind gusts over 100km/h across Prince Edward County, and East of Lake Huron. Peak wind gusts will likely reach or exceed 90km/h across the rest of Southern Ontario.

Projected Peak Wind Gusts through Late Sunday. We kept these projections conservative until the storm developes..

The sudden onset of warm air, rainfall, and extreme wind gusts will bring treacherous ice conditions across the Great Lakes. Ice shoves may be damaging to infrastructure along exposed shorelines. If you participate in winter activities such as, ice fishing or snowmobiling, it would be a good idea to remove your ice hut from the Great Lakes. Avoid snowmobiling until ice conditions improve.

A NEW COASTAL LOW BOMBS OUT AS IT TRACKS THROUGH THE MARITIMES

The powerful storm sweeps through Quebec on Sunday, and will subsequently phase into a strong ‘weather bomb’ south of Yarmouth. Potentially, deepening below 970mb (967-969mb).

While the exact phasing & extend of warm air advection is not entirely set-in-stone, it appears the heaviest swaths of snowfall will likely be off the Gaspe Peninsula shoreline and into the North Atlantic, thereby mitigating what could have been 2 or more feet of snow.

Southern New Brunswick will likely experience a rain/snow/wintry mix. With amounts totaling near 10cm. Amounts increasing to 20-30cm across the Northern extent of the Province. Pockets of heavier enhancement, accompanied by similar conditions is expected across Extreme Southern Newfoundland

Timing
Western New Brunswick – Late Afternoon Sunday
Most of New Brunswick – Sunday Evening
Nova Scotia – Sunday Mid Evening
PEI – Sunday Overnight
Newfoundland – Monday

Hardest Hit
Gaspe (35-45cm)
Bathurst (25-35cm)
Edmundston (30-35cm)
Campbellton (30-35cm)
Extreme Southern Shoreline of Newfoundland (25-40cm)

DANGEROUS BLIZZARD CONDITIONS STRETCH FROM JAMES BAY THROUGH NORTHERN QUEBEC

A major blizzard is on-tap for much of Northern Quebec. The worst of the treacherous conditions will be felt across the mouth of the Rupert River, Southeast of James Bay. Where rural communities can expect winds over 90km/h combined with 15-25cm of freshly fallen snow. Extensive blowing/drifting snow & near-zero visibility is expected. Isolated communities across Central & Northern Quebec may become cut-off, briefly.

New Brunswick

Mixed Precipitation for Eastern Canada & First Appreciable Snowfall…

A system developing in the Southeastern United States will track up the Eastern Seaboard this weekend, becoming a weather story across Eastern Canada.

SYNOPSIS:

A developing coastal system will bring a wintery mix across Southern Ontario, Quebec, and Northern New Brunswick. 

A boundary will form in Southern Ontario between a cold & dry high-pressure system, and moist air arriving from the Southeast. Colder air will overspread Southern Ontario and Southern Quebec Saturday, owing to a cold Northeasterly wind. Concurrently, a large area of precipitation will push north into Southern Quebec and Southern Ontario.

Snow, mixing, rain and freezing rain is expected from Saturday morning to Sunday evening. Flurries will continue through Monday.

Across, Nova Scotia, PEI and much of New Brunswick will see primarily rain. Although, Northern New Brunswick could remain as a mix or snow depending on the track of the developing system.

WPC forecasted fronts & precipitation types. Valid Friday evening.

SOUTHERN ONTARIO:

Many residents East of Highway 6 and across the GTA have started the day with moderate wet snow.

A cold northeasterly wind will reinforce colder air by Saturday evening. Mixing or rain-showers will transition into a wintery mix of wet snow & ice pellets east of Highway 6, along/north of highway 407/7. Continuing through much of Central and Eastern Ontario (away from the lake shore). A few wet centimetres is possible. Especially for municipalities at higher elevation South and East of Georgian Bay. Please plan accordingly, as conditions will deteriorate through the day Saturday.

MARITIMES: Strong Winds & Heavy Rainfall

This system will be a rain and wind story across much of the Maritimes. The strongest winds, with gusts between 80-90km/h, will be located across the Bay of Fundy. Elsewhere winds across much of Nova Scotia, PEI and New Brunswick are expected to be gusting between 50-70km/h Sunday morning. Total rainfall amounts between 20-50mm is expected by Sunday afternoon. The heaviest rain falling in Southern New Brunswick and coastal Nova Scotia. Across Northern New Brunswick, a period of snow and mixing may persist into the overnight. 

Forecast precipitation type & accumulation.

QUEBEC:

Flurries will begin north of the St. Lawrence Saturday evening. Montreal, and the Eastern Townships will likely changeover to rain late Saturday evening/overnight, with the arrival of warmer air. 

For regions north of the St. Lawrence, this will be a snow and ice story. Stay tuned to further forecasts Saturday night through Sunday morning, this region could see a 5-8 hour window for freezing rain.

Model depiction showing precipitation types late-evening Saturday, continuing overnight.