Rain changes to snow today in Montreal

Expect snow covered roads in Montreal by late today as temperatures drop below freezing.

Up to 5cm of snow is possible this afternoon into this evening across eastern Ontario and the St. Lawrence Valley. Rain will mix with and change to snow by 1pm in Montreal. Roads will become slippery as temperatures drop well-below freezing by the evening hours.

When I first started writing about the weather around the age of 10 or so, I would issue a first snow alert to my family and friends. The idea was that the snow, while not really a storm, was the first of the season, and would bring along with it the usual problems on the roads. So consider this your "first snow alert."

Our first measurable snow of the young season is on our doorstep this Friday morning. Weakening low pressure will move from the Great Lakes into New England, while a second area of low pressure develops and moves into Maine. A strong cold front will sweep across southern Quebec by the noon hour, bringing in the coldest air so far this fall.

Rain is currently falling in advance of the cold front. The rain will mix with and change to snow in the Ottawa Valley this morning and gradually across our region from west to east this afternoon. Expect 2-5cm for metro Montreal, with 10-20cm across the highest elevations of the Eastern Townships.

On the US side of the border, heavy snow is expected in the Adirondacks and Green Mountains, where winter storm warnings have been posted. Over 30cm is possible at the highest elevations. This will be an elevation dependent storm so from the valley floors up, amounts will increase.

Once the snow ends in Montreal tonight, the weather will turn blustery and cold. Expect northwest winds of 30-50km/h combined with a forecast low of -5C (23F), to produce windchills in the minus teens. Saturday will be cloudy, blustery and cold, with flurries and a high of only -4C (25F).

The sun will return on Sunday, but temperatures will remain chilly, with a high of -2C (29F).

First measurable snow of the season on the horizon for southern Quebec

The first accumulating snow of the season is expected late Friday and Saturday across southern Quebec. Roads are expected to become snow covered and slippery as temperatures drop below freezing Friday evening in Montreal, with rain changing to snow. The snow will end Saturday morning, with 5 to 10cm possible.

It is looking more and more likely that the first measurable snow of the season will fall across southern Quebec this upcoming weekend. This system has been on the weather models for several days now, showing up as early as last week. However, as with all potential winter storms, the devil is in the details, and that is often hard to pin down here in the St. Lawrence Valley. That being said, here is my best guess at our first snowfall.

High pressure will be in place for Wednesday and early Thursday, with fair skies and fairly cold temperatures. Overnight lows will be the coldest of the season so far, dropping down to -7C (19F) by Wednesday morning, and rising to 1C by late afternoon. Milder air will arrive on Thursday, with daytime highs going above the freezing point to 4C (39F). That mild air intrusion will remain in place in Montreal through mid-day Friday, assuring us a rainy start to the potential storm.

An upper level low is forecast to move across the Great Lakes and south of Montreal, accompanied by a rather strong cold front on Friday. Precipitation will start late Thursday persisting into Friday morning, and likely starting as rain. As cold air filters into the St. Lawrence Valley on Friday, precipitation should change to snow by late in the day. I think this will be a relatively light storm for valley locations, with a better chance for significant snowfall across the higher elevations, especially in the Eastern Townships and Green Mountains.

Low pressure will move south of Montreal this weekend, with the first snow of the season expected for portions of southern Quebec. (AccuWeather)

At this time, 5-10cm of snow is possible for metro Montreal through Saturday morning. Winds will become rather gusty as well, along with dropping temperatures. All in all, driving should be less than ideal Friday night. The snow should taper off to flurries in Montreal on Saturday, with a chilly high of -1C (30F). Snow will persist south and east of Montreal on Saturday.

I will post an update as the forecast becomes a little more precise.

Historic flooding slams British Columbia and Washington

Major flooding has swept the Lower Mainland and Fraser Valley of British Columbia after torrential rain fell on the region. Above, the Reliable Towing crew from the Discovery series Highway Through Hell were helping first responders rescue residents in Merritt. All 7200 residents were forced to evacuate on Monday after major flooding swept the city.  (CBC) 

An atmospheric river of moisture streaming across the Pacific Ocean slammed into B.C. and neighbouring Washington state early this week dropping historic amounts of rainfall. Over a stretch of 48 hours as much as 290 mm (11.5 inches) of rain fell over portions of Vancouver Island and the Lower Mainland. Over 20 individual all-time rainfall records were broken. Hope reported 295mm, Coquihalla Summit 238mm, Squamish 206mm and Malahat on Vancouver Island 182mm. The torrential rain liquified the soil creating mudslides and pushed numerous rivers over their banks. 

Major flooding occurred along The Malahat on Vancouver Island after nearly 200mm of rain in 48 hours. The highway was reopened Tuesday afternoon to alternating traffic. (BC Transportation)

Widespread, historic flooding has occurred, with every major highway connecting Vancouver to the rest of Canada closed due to washouts and mudslides. The Trans Canada (1), Crowsnest (2), Coquihalla (5) and Highway 99 are all closed at this time. First responders had to rescue hundreds of trapped motorists, many spending hours in the dark on ever shifting roadways. Sadly one fatality has been reported so far, a female motorist who was swept away in a mudslide on Highway 99. The fear is that the death toll may climb as numerous vehicles are reported in that slide.

Widespread flooding has been reported, especially in the hard-hit Fraser Valley. Hope, Merritt and Abbotsford have all ordered evacuations for many of their residents. Thousands of homes have been inundated. Flooding is also reported south of the border in Washington State. Interstate 5 had to be closed at Bellingham.

Both CP Rail and CN have reported damage to their respective tracks, with no train movement at this time between Kamloops and the busy Pacific ports.

The same storm produced blizzard conditions across southern Saskatchewan on Tuesday, with dozens of highways forced to close stranding travellers. (Regina Leader-Post)

The storm bombed out over Saskatchewan on Tuesday, producing howling hurricane-force wind gusts and blinding snow. Swift Current on the Trans Canada Highway reported a gust to 113km/h, with 11 hours of blizzard conditions and visibility under 1km. Dozens of highways were closed in the province, with near-zero visibility reported on area roads. The airport in Regina was forced to cancel all flights at 3pm Tuesday. The Regina Leader-Post newspaper cancelled home delivery on Wednesday morning.

Stormy weather pattern in place through the end of November

A clipper type low pressure system from western Canada delivered the first snowfall of the season for many portions of Ontario and Quebec on Sunday and Monday. Above, several centimetres of snow fell overnight in Saint-Jérôme, Quebec. (MeteoMedia Photo)

A series of storms are progressing across the country to start the week, delivering heavy rains, strong winds and snow to many regions. Starting here in southern Quebec, an Alberta Clipper delivered the first snow of the season for many late Sunday and into the wee hours Monday morning. Wet snow fell in portions of the Ottawa Valley as well as north of Montreal through the lower Laurentians. Several centimetres accumulated in places like Saint-Jérôme overnight. The air was just too warm in the St. Lawrence Valley for snow, however close to 8mm of rain did fall overnight at my home on Ile Perrot.

As colder air moves across the warmer waters of the Great Lakes, bands of heavy lake effect snow are expected to develop downwind across parts of Ontario Monday. Snow Squall warnings have been issued for Perth and Huron Counties, but some snow will extend outside the warning areas as well. A few flurries are still possible in Montreal on Monday, with a high of 5C (41F) forecast. More wintry weather is likely by late Tuesday and Wednesday in Quebec, with the chance for mixed precipitation before warmer air arrives briefly on Thursday.

As todays system slides off to the northeast, multiple fronts and areas of low pressure will arrive every other day in Montreal, bringing an unsettled mix of rain and snow to the region. By Friday a strong cold front will arrive accompanied by heavier precipitation and gusty winds. The unsettled and stormy weather pattern will persist right through the end of the month. I am seeing the potential for a big storm system on or about November 25, but as always, the devil is in the details, so stay tuned.

Torrential rain, widespread flooding and mudslides have closed several major highways across southwestern sections of British Columbia including the Coquihalla shown above. Over 100mm of rain fell in the Fraser Valley Sunday, with more forecast Monday. (B.C. Transportation)

Meanwhile a strong Pacific storm produced torrential rain on Sunday across coastal B.C. and into interior sections. The rain, in some cases over 100mm, has produced widespread flooding. Numerous highways are closed due to mudslides and flooding including the Trans Canada and the Coquihalla from Merritt to Hope. According to B.C. Transportation, both Highways 1 and 5 have been breached in several locations, and no estimate can be given as to when the routes may be reopened. First responders are working to free many motorists who are now trapped on the closed roads.

The City of Merritt has declared a state of emergency, with several evacuations ordered. Flood warnings have been posted due to the combination of heavy rain and melting snow. Numerous rivers are at or have exceeded flood stage across southwestern British Columbia.

As the storm lifts across the Rockies, heavy snow and fierce winds gusting over 100km/h are forecast for portions of Alberta and Saskatchewan through Tuesday. The heaviest snow will be across central regions, with the strongest winds along and south of the Trans Canada Highway.

Colder weather returning to southern Quebec

A spectacular early sunset Monday afternoon in Montreal. With the move back to standard time last Sunday, the days are terribly short with the sun setting at 4:30 today. Thankfully the weather has been bright and sunny.

We are coming to the end of another spectacular stretch of fall weather in Montreal. Temperatures have been above normal, well into the teens, along with abundant sunshine and no precipitation. We can expect one more day of pleasant weather Thursday, however temperatures will be cooler, with overnight lows near 0C (32F) and a daytime high of 8C (47F) on Thursday.

High pressure has been in control of our weather, with the heavier cloud cover and any precipitation remaining south of our region. That will change as the week comes to an end. Strengthening low pressure over Manitoba will slide into the upper Midwest and then across the central Great Lakes into the weekend. This system will provide southern Manitoba and northwest Ontario with the first snowstorm of the season. Heavy snow is forecast across those regions from Thursday into the weekend. Between 10 and 20cm are expected across southern Manitoba, with 20 to 40cm in northwest Ontario, west of the storm track. The snow will also spread into neighbouring portions of North Dakota and Minnesota.

As the storm deepens, howling winds are forecast across the upper midwest and Great Lakes. The storm will remain well north and west of Montreal, lifting a warm front across the St. Lawrence Valley late Thursday, followed by a potent cold front on Friday. A period of gusty winds and steady rain is likely Friday, before temperatures begin to drop heading into the weekend. Behind the cold front, below freezing temperatures are expected in Montreal for overnight lows, with daytime highs in the low single digits starting Sunday. There is a chance of some light snow or flurries overnight Sunday into Monday, but no accumulation is anticipated at this time for Montreal.

Another low pressure area is forecast to develop along the east coast early next week, but remain well southeast of Montreal. Temperatures are expected to remain below normal well into next week.

The 30th anniversary of The Perfect Storm

Massive waves smash into the coast in Scituate, Massachusetts in late October 1991. The Halloween Nor'Easter or Perfect Storm as it would later be called, was responsible for 13 deaths from Newfoundland to North Carolina, and over $200 million dollars in damage. (WBZ)

This week marks the 30th Anniversary of one of the strongest unnamed storms to impact the eastern seaboard. The hybrid system was the coming together of strong low pressure located east of Nova Scotia, hurricane Grace moving northward from the tropics and a cold front sliding off the New England coast. The end result was a powerful ocean storm that developed on October 28 and persisted into early November 1991. I knew the system as the Halloween Nor'Easter, but it would later be referred to as "The Perfect Storm".

What made this storm so unusual was the huge area upon which its impacts were felt. Towering waves spread along the coast from Newfoundland to Puerto Rico.  The toll on the marine community was significant with several vessels lost or damaged at sea, and many others destroyed in port. The Coast Guard conducted hundreds of rescues, including the crew of a New York Air National Guard helicopter that ditched into the Atlantic after running out of fuel. Sadly one crew member was lost at sea.

No loss was more infamous than that of the Andrea Gail, a 72 foot commercial sword fishing boat out of Gloucester, Massachusetts. The Andrea Gail and her crew of 6 would disappear approximately 290 kilometres northeast of Sable Island, Nova Scotia on October 28 at around 6pm. An exhaustive search by both the Canadian and US Coast Guard would only turn up scattered debris but little else. At the time of the sinking, seas were a record-breaking 30 metres high (100 feet) in the area where the Andrea Gail was last reported, and across the Scotian Shelf. The story of the Andrea Gail would later be told in a best selling novel by author Sebastian Junger called The Perfect Storm. The book was adapted into a movie in 2000 staring George Clooney.

The Halloween Nor'Easter was the coming together of several key ingredients into a once in a lifetime storm. The unnamed storm would have likely been a hurricane if naming criteria was then as it is today. It was National Weather Service Meteorologist Robert Case, when interviewed several years later, who described the system as "The Perfect Storm". (Accuweather.com)

Along the coast, the storm was ferocious, with 25 to 30 foot waves crashing into homes and businesses. Hundreds of homes were destroyed, many others were left uninhabitable. Coastal infrastructure including roads, piers and ports were destroyed. Widespread power outages were reported, with wind speeds exceeding 100km/h. Coastal New England was particularly hit hard. I visited the New Hampshire and northeast Massachusetts coastlines in November 1991, shortly after the storm hit. Major damage was visible everywhere. Another hard-hit are was the Outer Banks of North Carolina. Several hundred homes were damaged or destroyed and roads were closed by water and sand accumulation. I had been on the Outer Banks during the third week of October 1991, and just missed the storm.

As October turned to November, the storm was not finished, strengthening into a post-tropical cyclone and slamming into Nova Scotia on November 2. The Perfect Storm hit Atlantic Canada hard, with flooding, wind damage, power outages and over 100cm snow in Newfoundland. Widespread damage occurred, several boats were destroyed and power was out in large portions of Nova Scotia and Newfoundland.

By the time the storm moved away from North America, the death toll was 14, including 1 in a weather related traffic accident in Canada, with damage estimates exceeding $200 million.

NOAA Satellite image of "The Perfect Storm" located south of Nova Scotia on October 30, 1991