Thursday, March 30, 2017

More snow forecast for southern Quebec and Ontario

A late winter storm will provide plenty of sloppy travel across the Northeast US, southern Quebec, and eastern Ontario, from Friday into early Saturday. (AccuWeather)
Stubborn low pressure over eastern Canada has maintained a cool northerly flow for most of this week in Montreal. Combined with low clouds and fog, it has not been a very pleasant stretch of weather. Sunshine will make a brief appearance Thursday as high pressure crests over the area. This will provide us with a near perfect early spring day, expect a high temperature near 7C (45F) and light winds.

Late Winter Storm
Now the bad news, the good weather will be very short-lived. Low pressure is forecast to develop today and strengthen as it move across the Ohio Valley and southern New England on Friday. A plume of moisture arrives Friday in the form of snow mixed with a cold rain. All precipitation goes over to wet snow late Friday evening in Montreal, becoming heavy at times. Forecast accumulations appear to be in the 10 to 20cm range, the highest in northern New York, Vermont and the Eastern Townships. Montreal and Ottawa should have close to 10cm by Saturday morning. The storm will be terrain driven, with the highest accumulations expected in the hills and mountains, lowest amounts on the valley floors. Some mountain locations in southern New England may see up to 30cm (1 foot) of heavy wet snow. The weight of the snow may pose a problem to power lines and trees depending on how much you receive. The temperature in Montreal will be 3C (38F) Friday, but drop once the snow starts to around the freezing point. Precipitation should end Saturday, along with partial clearing and milder temperatures. It should all be a bad memory by Sunday, with sunshine expected and a high of 10C (50F) in Montreal.

Sunday, March 26, 2017

Warmer weather returns - but first freezing rain for Montreal

Not very spring-like, but still beautiful on L'Ile Perrot and across southern Quebec early Saturday morning. This was the result of a surprise 10-15cm snowfall on Friday. (ValeyWX Photo)
Environment Canada has posted a freezing rain warning for southern Quebec and eastern Ontario. Low pressure over the southern US will push a warm front north towards the Canadian border on Monday. This is the same front that delivered a surprise, heavy snowfall on Friday to both Montreal and Ottawa. Most forecasters were expecting a limited snowfall of perhaps 2-4cm. Montreal received 11.4cm of snow, breaking the daily record for March 24 of 8.6cm established in 1991. Ottawa received 22cm of snow, smashing the 50 year old daily record of 6.4cm set in 1966.

The aforementioned warm front returns today, pushing an area of precipitation ahead of it this afternoon, into the colder air at the surface here in Montreal. A period of freezing rain is forecast from late this evening into the overnight hours. Temperatures are cold this morning, -7C (19F) in Montreal, but will warm above freezing overnight. By Monday, plain rain is expected with improving travel conditions, and a high of 2C (36F). Before the temperature warms however, a decent 2 to 10mm of ice is expected across the region. Travel will be impacted from late this afternoon into the wee hours of Monday morning. 

The same icy conditions are expected in northern New York and New England. The balance of the week will be much milder, with daytime highs approaching 10C (50F). Perhaps spring has finally sprung...perhaps.

Tuesday, March 21, 2017

Spring has sprung across southern Quebec - or has it?

A local garden centre on L'Ile Perrot welcomed the arrival of spring this weekend by placing flowers out, in spite of all the snow from last week's blizzard. (ValleyWeather Photo)
Spring officially arrived at 6:29am on Monday morning, along with sunny and mild weather. The massive snowstorm from last week is quickly becoming a painful-but-distant memory. Tons of snow have either melted or been carted away. On average, over 90 percent of city streets have already been cleared, aided by mild weather and no additional snow. The normal daytime high for Montreal is now above freezing at 5C (41F). However, we still have some winter left to go...

ARCTIC FRONT
A rather strong arctic front will push across southern Quebec late this evening and into the overnight hours. The front will be accompanied by brief, but at times intense, snow squalls. A dusting of perhaps 3 or 4cm of snow is possible. Winds will become strong and gusty out of the northwest, up to 60km/h. More importantly, the temperature will plummet to early-morning lows of -15C (5F) across southern Quebec. Wet roads will likely freeze rapidly late tonight, with icy spots and slick driving expected into the morning commute. Windchill values will drop into the minus 20s. Wednesday will be windy and cold with flurries. Temperatures will struggle to reach -10C (14F). The weather will moderate quickly in the latter part of the week. Sunshine is expected Thursday, with high temperatures approaching 0C (32F). More precipitation should arrive on Friday and persist into the upcoming weekend.

Friday, March 17, 2017

The calm after the storm - Blizzard 2017 vs 1971

The massive $25 million cleanup is underway in Montreal. Nearly 10,000km of roads need to be cleared of the 50cm of snow from the blizzard of 2017. (CTV News)
The list of impactful winter storms in Montreal and southern Quebec is way too long for this blog. The '98 ice storm certainly is the champion, there is no disputing that. Having said that, there are a few others that stand out. Each storm is different than the one before. What can be a disruptive and memorable storm for some, proves to be nothing but a nuisance for others. Often, it depends on your own experience as to whether or not a storm is memorable. As I have often written, I lean towards the 1971 storm, both from the science side and from my own personal experience.


The calm after the storm. Skies have cleared and milder temperatures are helping with the big clean-up. (ValleyWeather)

March 13-15 2017
Of the many snowstorms that have hit the city in the last 100 hundred years, three have stood out above all the others:  March 3-5, 1971, March 13-14, 1993 and December 27, 2012. You can now add a very respectful March 14-15, 2017 to the mix. The numbers from this week's storm are impressive to say the least. Total snowfall ranged between 40-80cm across southern Quebec. In Montreal, the bulk of the 40-50cm fell in less than 12 hours. A peak wind gust of 106km/h was recorded at Trudeau Airport, the strongest in March since the 1971 storm. Blizzard conditions were observed for 8 consecutive hours. Several highways were closed, littered with cars in some cases. A rash of major multi-vehicle accidents occurred. The Highway 13 fiasco will be talked about for decades to come. At least 8 fatalities are now being blamed on the storm. An entire generation of school kids had their first snow day ever, a very rare occurrence in Montreal these past few decades.

December 27, 2012 
In December 2012, Montreal recorded 45.6cm of snow in less than 24 hours, breaking the long standing record from 1971. The storm occurred during the holiday season, so the impact was minimal, as most people were already at home. The snow was extremely heavy, but the wind rather tame by winter-storm standards, less than 50km/h. At no point in 2012 were true blizzard conditions observed at Trudeau Airport. Roads were clear the next morning.

March 13-14, 1993
The March 1993 Superstorm was a powerhouse. The impact of this large winter storm was felt from the Gulf of Mexico to the Arctic Circle. In southern Quebec, the storm arrived on Saturday evening into early Sunday morning. The timing offset the full impact of 41cm in less than 12 hours. Numerous roads were impassable, but only for a few hours. Wind speeds were in the 40 to 70km/h range. At no point were blizzard conditions reported at Trudeau Airport.

The 1971 "Storm of The Century" still stands out as the worst snowstorm to hit Montreal. The 43.2cm that fell on March 4, 1971 was driven by winds in excess of 100km/h. The blizzard closed the city for days. (Photo: Montreal Archives)

March 3-5, 1971
The March 3-5, 1971 "Storm of the Century" still ranks as the biggest snowstorm to strike the city. The amount of snow that was already on the ground in 1971, combined with unseasonable cold and relentless winds over 80km/h, produced a fierce blizzard in Montreal. Many roads closed, forcing commuters to stay in the city, packing downtown hotels. The storm dumped close to 50cm on Montreal over two days. True blizzard conditions were observed for almost 11 hours, including 5 consecutive hours with zero visibility. Widespread power outages occurred. The city came to an abrupt halt for nearly three days. The Montreal Canadiens had to cancel a game, the one and only time ever due to weather. Drifts were over 6 feet high, with 30 fatalities attributed to the storm.

Wednesday, March 15, 2017

Record breaking snowstorm slams Montreal

Motorists spent the night on Highway 13 south in Lachine. (CJAD)

42cm of snow and counting on L'Ile Perrot (ValleyWeather)

Powerful winds and heavy snow have placed this storm among the greatest hits of Montreal, March 4, 1971 and March 13, 1993.

What a storm! Heavy snow combined with very strong winds swept across southern Quebec on Tuesday afternoon. The snow resulted in an evening commute, that is some cases continued into the overnight. Visibility was less than 400 metres for over 5 hours, this classifies this storm as an official blizzard. The snow fell in Montreal at a rate of 3-5cm an hour between 5 and 8pm. A peak wind gust of 106km/h was recorded around 6pm.

This morning, we are left with over 40cm on the ground in Montreal, 60-75cm from south shore St. Hubert into the Townships. Numerous highways remain closed this morning, including Highway 13 south near Highway 20. This was the scene of a truck accident last evening that resulted in motorists spending the night in their cars. Officially, Montreal Trudeau Airport measured 32cm for the day, surpassing the previous record of 24.9cm set in 1961. Most of the snow fell in the 2pm to midnight time frame on Tuesday. Major multi-vehicle accidents occurred along Highway 20 near St. Zotique, Highway 10 near Granby and Highway 401 near Mallorytown, Ontario. All three accidents have closed those roads. In the Mallortytown accident, one fatality was reported, along with a dozen injuries.

Schools and Universities are closed today in Montreal, Laval, Vaudreuil and across the Townships. Additional snowfall of 5-10cm is likely today across southern Quebec, along with blowing and drifting snow. Winds are forecast in the 30 to 50km/h range. Avoid travel if possible.

Tuesday, March 14, 2017

Massive winter storm blasts southern Quebec and Ontario

Highway 401 remains closed this afternoon at Mallorytown, Ontario, west of Brockville, after a major accident involving 30 vehicles.
Blizzard conditions have moved into southern Quebec this afternoon, making travel very dangerous. Heavy snow, falling at a rate of 3 to 4cm an hour, is forecast for the next several hours in Montreal. Winds are increasing at this hour, gusting to 65km/h at Trudeau, with the visibility down to 0.4km. Highways are treacherous to say the least, with numerous accidents reported. Highway 20 is closed at St. Zotique, Quebec. Highway 401 is closed in both directions at Mallorytown, Ontario, after a 30 car collision involving several trucks and a chemical spill. There are reports of serious accidents on Highway 40 in Montreal and Highway 30 on the South Shore. Highway 15 south of the city to the US border is not recommended. New York State Police have closed Interstate 87 from Champlain to Albany. You will be turned around at the border.

All this weather is thanks to a very strong Nor'Easter located near Cape Cod this afternoon. The storm is forecast to move northeast into Maine on Wednesday. Heavy snow and strong winds will continue in southern Quebec through Wednesday morning, with 30 to 50cm expected. Travel is being discouraged. There are many delays at Trudeau Airport. Call ahead. The temperature remains cold in Montreal, -9C with a windchill around -20C. Temperatures will remain steady throughout the storm.

Blizzard conditions to impact Montreal

A powerful winter storm will give Montreal blizzard conditions later today. (AccuWeather)
Winter Storm and Blizzard Warnings are posted across southern Quebec, eastern Ontario, New England and New York today. Low pressure is travelling close to the coast, therefore more snow is forecast for our region.

Blizzard conditions are expected in the St Lawrence Valley, including Montreal and Quebec City today, as a large winter storm develops along the American east coast. The storm in question is deepening rapidly this morning near Norfolk, Virginia. The low pressure will strengthen and lift northeast towards Long Island by this afternoon. Snow will move from south to north today and reach Montreal by midday. Very light snow is occurring locally this morning, well ahead of the main show. The steady snow will arrive by noon and taper off Wednesday. Accumulations of 20 to 30cm are likely in Montreal, with 15-25cm in eastern Ontario, and 30-60cm in the Townships and New England. Winds will increase dramatically this afternoon, gusting from 50 to 100km/h in the St Lawrence Valley. The temperature will remain cold through the storm, within a couple of degrees of -8C (18F).

Blizzard
The National Weather Service in Burlington has gone ahead and upgraded the warnings to blizzard status for their side of the St. Lawrence Valley. Environment Canada defines a blizzard as 40km/h winds, falling or blowing snow, and visibility below 400m (0.25 mile) for at least 4 hours. This criteria will likely be met in Montreal later today and this evening. Travel across the entire region is not recommended today. This is especially true for any highways along the St. Lawrence River including Highway 20 to Quebec City and Highway 401 to Toronto. Some New England states actually have travel bans in place. Air travel has already been severely impacted, with thousand of flights cancelled today, call ahead. This storm has the potential to be quite historic for many locations.

Monday, March 13, 2017

Powerful Nor'Easter to impact St. Lawrence Valley

The forecast arrival time of the snow from late Monday into Tuesday. (AccuWeather.com)
A very strong winter storm is poised to bring heavy snow and strong winds to Montreal and most of southern Quebec, from midday Tuesday through Wednesday.

Winter storm warnings are now in effect for southern Quebec, New Brunswick and all of New England. Blizzard warnings are posted for coastal regions from New Jersey to Maine. Low pressure is forecast to develop east of Cape Hatteras tonight and move northeast towards Cape Cod. The rapidly-deepening storm is forecast to become a classic Nor'Easter, fueled by Atlantic moisture and backed by the record-cold air that lies inland over our region. Snow is forecast to spread from south to north on Tuesday, reaching Montreal after the noon hour. The snow will become heavy, driven by increasing northeast winds of 70 to 100km/h in the St. Lawrence Valley.

Widespread blowing snow will make travel very difficult across the entire northeast and Quebec. Visibility will frequently be reduced to near zero. Portions of eastern Ontario will also have heavy snow and blowing snow. Storm totals are expected to be in the 15 to 30cm range in Montreal, 30 to 45cm in the Townships and New England, and 10 to 15cm in eastern Ontario. Temperatures will remain cold throughout the storm, with no risk at all of mixing. As with all coastal storms, these numbers are based on the current forecast track. Any deviation in that track can increase or decrease snow amounts significantly. Updates will be posted frequently via twitter @valleyweather2 and @TheSuburbanNews.

Sunday, March 12, 2017

Late winter storm to impact southern Quebec

A strengthening coastal storm will impact southern and eastern Quebec this week. (AccuWeather)
As is often the case, March can be a very difficult month to get through. Many large winter storms have impacted Montreal over the decades, and this March may be no different. We are coming off an extremely cold weekend, with high temperatures on Saturday of -15C, and Sunday -12C, over 15 degrees below normal. The weather will remain very cold to start this week, along with a potential major winter storm. The storm in question is forecast to develop rapidly off  the Carolina coast on Monday, and approach southern New England by Tuesday. The system will then lift northeast into Atlantic Canada. Montreal will remain on the northwest edge of this classic Nor'Easter, with snow developing midday Tuesday and persisting into Wednesday morning. Strong winds are expected as well, creating blowing and drifting snow.

What is not clear at this time, is how much snow will fall. As is often the case with coastal storms, a difference in the storm track of  less than 100km can mean 30cm of snow or just flurries here in Montreal. At this time, guidance suggests 10-15cm for Montreal, with less snow north of the city and over 30cm as you move south into the Townships, Vermont and New York. Travel will be impacted, not just here in Montreal, but also up and down the northeast US coast. A winter storm watch is in effect for Vermont and New York. Watches or warnings may be posted for portions of Quebec by Monday. Along the coast, blizzard conditions are forecast in New York City and Boston, along with very strong winds and potential coastal flooding.

This is a rapidly changing weather situation. I will post further updates on Monday.

Thursday, March 09, 2017

Wild windstorm blasts Ontario and Great Lakes basin

Just one of the hundreds of trees that fell across the Great Lakes basin on Wednesday. (CBC Windsor)
We can call it the storm that just won't go away. A monster of a low-pressure system that developed in Montana last weekend is still spinning across far northern Canada. The storm has been responsible for one form or another of severe weather for almost half the North American continent. The week started with a ferocious blizzard across the northern plains and eastern Prairies. Brandon, Manitoba had 41cm of fresh snow, along with winds of 90km/h, producing an incredible 31 consecutive hours of visibility below 400m (0.25 miles). Lynn Lake had 67cm of snow. The storm center deepened rapidly as it swept north, with a hurricane-like low pressure of 95.03kPa (950mb) at Winnipeg, Manitoba, 93.41 kPa (934mb) at Kenora, Ontario and 93.25 kPa (932mb) at Sioux Lookout, Ontario.

The strong winds not only produced the blizzard, but also fanned brush fires in the southern plains and Midwest. In addition to the wind, strong thunderstorms and tornadoes produced widespread damage, with fatalities across the central US.

By Wednesday, it was the Great Lakes region, southern Ontario and even western Quebec that felt the impact of this system. Winds gusted over 100km/h from Michigan and Ohio into western New York and Ontario. The wind cut power to millions of homes, one million in Michigan alone. According to Hydro One, 68,000 clients were in the dark in southwest Ontario. Numerous accidents were reported, as semi-trucks were blown off highways. Ontario Provincial Police were forced to close the Burlington Skyway for hours, after it became too dangerous to negotiate. Widespread structural damage and tree loss were reported. Many of those trees crashed onto homes and cars. Extensive damage was also observed in western New York, including Greece, Rochester and Buffalo. In Detroit, an arson fire was blown out of control by 100km/h winds, resulting in five fatalities. In Ontario, a peak wind of 115km/h was observed at Hamilton, with 91km/h at Toronto Island. In Montreal, winds gusted to 85km/h around 4pm. In the wake of the storm, frigid air will pour into southern Ontario and Quebec over the next few days. Winds in southern Quebec will continue to gust between 30 and 50km/h through Friday.

Wednesday, March 08, 2017

The temperature roller coaster ride continues for Montreal

The strongest winter storm of the season is winding down in Manitoba and Saskatchewan today, after two days of 90km/h winds and zero visibility. (Photo: Manitoba RCMP via Twitter)
March is often a month of sharp contrast as winter and spring try to negotiate the atmosphere. In the last week, Montreal has had record high temperatures, as well as overnight lows in the minus 20s. On Monday night, over 7mm of freezing rain produced icy roads and sidewalks leading to numerous accidents. Today however, the temperature is all the way up to 9C (48F) at Trudeau Airport, just a couple of degrees shy of yet another record high. But you guessed it, this will not last. Two potent cold fronts are in our future, associated with a strong winter storm that swept from Montana north towards Hudson Bay.

The first cold front will arrive Wednesday night, with a couple of centimetres of snow and plunging temperatures. By Thursday morning, the mercury will have fallen all the way to -5C (23F). A second stronger arctic front will arrive late Friday, accompanied by gusty winds, snow squalls and even colder temperatures. This weekend will be a repeat of the last, expect plenty of sunshine, but with frigid temperatures for March, lows near -20C (-4F) and daytime highs of -10C (14F). As we look ahead into next week, the colder than normal temperatures will remain through at least mid-week. There is also the potential for some accumulating snow on Tuesday. The eventual track and intensity of the system will dictate how much snow may affect southern Quebec. At this time, Montreal may remain on the northern edge of the system

Prairie Blizzard
Over the last 48 hours, a fierce blizzard has raged over portions of Manitoba and eastern Saskatchewan. Heavy snow and strong winds, in excess of 90km/h, have produced hours of zero visibility. The blizzard conditions forced the closure of dozens of highways, including the Trans Canada, stranding hundreds of travelers. Dangerously cold temperatures accompanied the storm, the strongest of the winter season. In Estevan, visibility was less than 1kilometre for over 36 hours, from late Monday into Wednesday. This included at least 9 consecutive hours of zero visibility. The weather made travel virtually impossible. The storm arrived suddenly late Monday, with the mercury falling in Winnipeg from 6C (43F) down to -6C (21F) in less than one hour. Winds are beginning to lighten Wednesday as the storm moves north into Hudson Bay.

Thursday, March 02, 2017

Arctic chill returns to Montreal

Thin ice remains on the St. Lawrence River off L'Ile Perrot. Low clouds, fog and a stubborn northeast wind on Wednesday, prevented Montreal from reaching record high temperatures. Such was not the case in locations just to our south and west, where temperatures were as warm as 16C. (ValleyWX Photo)
In a scenario similar to this past weekend, record highs are being followed by arctic air in southern Quebec. On Tuesday, Montreal reached 8.3C (48F), tying the record high for the date, set in 1954. Wednesday, a stubborn northeast wind separated Montreal from the warm air just to our south and west. While Trudeau Airport squeezed out a 7C (45F) high very late in the day, Granby, Sherbrooke, St. Anicet, Cornwall, Brockville, Massena, NY, and Burlington, Vermont all established new record highs for the date. Burlington reached 17C (63F), their third record high in less than a week. Brockville recorded 16C (61F); however, this morning they have plummeted to -9C (16F), all in less than 12 hours. Here on L'Ile Perrot, the temperature dropped from 5.4C (42F) at midnight to -7C (19F) at 7am.

A strong cold front surged across southern Quebec overnight, accompanied by a rapid temperature drop, winds in excess of 60km/h, and light snow. The light snow will persist for most of the day, accompanied by strong winds and biting windchill values. Accumulations will range from 1 to 3cm. The high temperature has been reached for the day, with the mercury falling to overnight lows of -15 to -20C in southern Quebec by Friday morning. The wind will remain gusty through Friday, producing windchill values in the minus 20s. Skies will clear out tonight, with sunshine returning through the weekend. The temperature will remain cold, with daytime highs around -8C (18F) and overnight lows down to -18C (0F). Above-normal temperatures are expected to return early next week.