A Nor'Easter before the first Atlantic Hurricane

A spectacular September sky as departing clouds play with the rising sun over Ile Perrot. The lowering angle of the fall sun allows for some beautiful sunrises and sunsets. (Valley Weather Photo)

Monday is the last official day of summer for 2026. I am still in shock the season is coming to an end, and stubbornly wearing shorts while waking my new pup on 6C mornings. I got to be me. While I absolutely enjoy all four seasons, summer is by far my number one. With that being said, fall arrives, like it or not, at 8:04 pm on Tuesday.

With that we are seeing much cooler nights in Montreal as daylight diminishes, along with an increase in morning dew, which will eventually become frost as we cool even more. The good news is that the weather looks spectacular in Montreal, with strong high pressure slowly drifting over southern Quebec for the entire week ahead.

As far as sensible weather is concerned, expect nothing but sunny, seasonable days and clear, crisp and cool nights. There is even a risk of frost across large portions of the upper Ottawa Valley as well as regions well north of Montreal. Frost advisories have been issued for those locations. Daytime highs will range from 16C (60F) up to 20C (68F) by Friday. Morning lows will be on the chilly side, ranging from 2C (36F) off the island of Montreal, increasing to 5C to 7C (40-45F) across metropolitan regions. 

Weekend Nor'Easter

As high pressure continues to suppress any significant weather well to our south this week, strong low pressure is forecast to develop along the Atlantic coast and move north towards southern New England by Friday night. This will be the first Nor'Easter of the young fall season, oddly occurring before the first hurricane in the Atlantic basin. It is a record-setting year, as our strengthening El Nino continues to put a cap on tropical activity in the Atlantic Ocean. We are still awaiting our first hurricane.

This year will be the latest on record for a hurricane to form, the previous benchmark was Hurricane Gustav on September 11, 2002. So far this year we have had only 6 tropical storms, including the current system, Fay, located 655km southwest of the Azores and weakening.

As far as Montreal is concerned, it appears the weather from next weekends potential storm should remain well south and east of the St. Lawrence Valley. Perhaps a few clouds, sprinkles and a chilly northeast wind on Saturday, but maybe nothing at all. Closer to the system, heavier rain, up to 50mm, strong winds and even some coastal impacts would be possible, but that will depend on the final strength and eventual track of the storm. Stay tuned, it's that time of year again.

Above normal temperatures expected for September

The rain stopped long enough last weekend for thousands of spectators to attend the annual car show in Hawkesbury, Ontario. The weather was perfect with light winds, low humidity, 25C and just a wisp of clouds. The perfect weather resulted in nearly 450 classic cars on display. It was a blessing after a summer where so many outdoor events have been rained out. (Valley Weather Photo)

The weather has been rather mild to start the month of September across southwestern Quebec, with indications that it will remain that way. We are at the start of what is expected to be an historic El Nino event, the warming of the waters in the equatorial Pacific Ocean. Typically this means a very moderate if not warm fall and winter season for Montreal and a large portion of Canada. Looking ahead, we can certainly see signals of milder-than-normal weather well into October for the Montreal region.

Warm high temperatures so far this month have reached the middle 20s. with lows remaining in the middle to upper teens. Warm southwest winds on Thursday have been gusting in excess of 60km/h. The wind managed to keep temperatures up overnight, with a low of 19C (66F) at Trudeau Airport. The normal high and low for early September is 20C (68F) and 10C (50F) respectively. We have not seen that, and shorts and t-shirts remain the clothing of choice.

We have managed some decent rainfall to start the month, with officially 49mm at Trudeau Airport, thanks in part to heavy showers on Wednesday evening that produce close to 30mm in just a few hours. I have recorded 44mm here on Ile Perrot.

High pressure will maintain sunny and mild weather well into the weekend, with the next chance of showers coming late Sunday.

Torrential rain on Labour Day weekend washed away roads, flooded homes and destroyed cars across Cape Breton Island in Nova Scotia. The storm resulted in one fatality and prompted a state of emergency across the region. Over 200mm of rain fell in juts a few hours. (Province of Nova Scotia)

It has been a very expensive summer for Canadians coast to coast, as storms and fires have resulted in billions of dollars in insured losses. The most recent storms in Toronto and Cape Breton, Nova Scotia have only added to the totals. In the Windsor storm, two tornadoes moving southeast for Michigan resulted in significant widespread damage to trees, cars, homes and businesses. The September 2 storm resulted in at least 1000 calls to public works for tree removal, 600 of those deemed urgent. Many fell onto homes and cars. The Toronto storm on September 1st, severely damaged Rogers Stadium, resulting in the cancelation of the AC/DC concert that was scheduled for September 16.

Last weekend, a torrential rainstorm dumped over 200mm (8 inches) on Sydney and parts of Cape Breton in Nova Scotia. Torrents of water washed away roads, damaged homes and resulted in one fatality. The damage from this storm alone will run into the hundreds of millions. With an El Nino fueled fall and winter season forecast, we can expect more of the same, with unusual weather patterns creating the potential for dangerous, damaging storms. 

Labour Day, the unofficial end to summer in Montreal

A tranquil weather moment from the heavens as the clouds part at sunrise this week in Montreal. It has been a challenging summer as far as the weather is concerned from coast to coast, with searing heat for some, drought, fires and floods for others. The increasing strength of the current El Nino is sure to make this fall and winter forecast just as challenging to say the least. (Valley Weather)

Labour Day weekend is upon us, typically the unofficial end to summer. This was more of a reality in my youth, as the weather typically turned cooler much quicker and school rarely started until after the last long weekend of the summer. Things has changed considerably these days as most schools are already back in session, and summer warmth tends to drift well into September and in some cases even early October. 

The weather this weekend looks ideal for outdoor activities. Scattered showers are possible Saturday as a stubborn upper level low remains to our northeast, but the day should not be a washout. Sunday and Monday will feature nothing but sunshine, with daytime highs rising into the middle 20s and overnight lows in the low teens. 

You can definitely feel summer slipping way as the longer nights tend to produce a heavier dew in the mornings, as well as fog in places. Overnight low temperatures can easily find their way into the low teens. The trees are also beginning to respond to the shorted amounts of daylight, which typically begins the leaf changing process, despite how warm it is.

It was Toronto's turn this week to join Montreal and Ottawa in the summer of the flood. A powerful thunderstorm on Wednesday afternoon resulted in close to 140mm of rain falling in less than one hour, flooding residents, highways and underpasses across parts of the city. (Toronto Tourism) 

Toronto's 100 Year Storm

It has been the summer of fire and flood across Canada. You can now add the Greater Toronto Area (GTA) to the growing list of communities impacted by significant flash flooding events. Powerful thunderstorms on moved southeast off Lake Huron Wednesday afternoon, racing across the Toronto and Niagara regions and into western New York.

The storms produced widespread wind, hail and flooding, resulting in significant damage  as well as power outages to more than 150,000 homes and businesses. Wind gusts were observed up to 91km/h at Brantford and 83km/h at Pearson Airport. Major damage was reported at Rogers Stadium. Hail as large as 2.5 to 6.5cm punched out windows in homes and cars in North York. Several motorists had to be rescued after 139mm of rain fell in Caledon, with 133mm at Vaughan. A tornado was reported near Bamberg, northwest of Kitchener.

Severe thunderstorms on Thursday resulted in significant damage across this east Windsor, Ontario neighbourhood. (Photo: @onlocation.tv)

On Thursday another round of strong thunderstorms moved across southeast Michigan into the Essex/Windsor area. The powerful storms and possible tornado tore the roof off at least one home spreading debris across the east Windsor neighbourhood. Large, mature trees were uprooted, many landing on homes and cars or blocking streets. Once again large hail and torrential rain fell as well. The Northern Tornadoes Project out of Western University in London will be investigating the storm dame Friday. They suspect based on radar and reports from neighbouring Detroit, that two tornadoes may have impacted the area between Windsor and Amherstburg.

Welcome to meteorological fall

A developing thunderstorm over the St. Lawrence River off Ile Perrot on Thursday, August 27. Summer 2026 will be remembered across Canada for wildfires, flash floods and tornadoes. In Montreal, our weather seemed constantly unsettled, as if Mother Nature was irritated. (Valley Weather Photo)

Back to school, sunsets before 7pm, my snow clearing contract arrives as well as my tire change reminder for October. It must be September in Montreal!

September 1st marks the start of meteorological fall, statistically summer is behind us. The nights grow longer quickly, we see more dew and fog, and already, there is a hint of colour in the trees that will only increase over the coming days. 

The summer months in Montreal flew by at lightning speed as they often do. It was an odd summer to say the least, warm and humid, but nothing earth shattering as far as extreme heat is concerned. Officially the airport managed only seven 30C days, and only one heatwave during the first week of July. It was a wet summer, with the rain falling in bunches, including the June 20 storm that dumped 50 to 200mm on the parts of the city, mainly the West Island and South Shore. 

The flash flooding from the July across parts of the West Island of Montreal will probably end up being the weather story of the year. 

In terms of temperatures, the summer will end warmer than normal, but not record shattering. The average temperature at Trudeau Airport was 20.5C for June (normal 19.0C), 22.9C for July (normal 21.7C), and 21.1C for August (normal 21.1C).

As mentioned it was a wet summer, with precipitation falling on 10 of the 13 summer weekends since June 1st.

What can expect in September and beyond? An El Nino (the warming of the equatorial Pacific Ocean) is well underway, and expected to become a super El Nino. We have already witnessed the results of this across North America, with an active fire season, along with surpassed heat here in the east. The Atlantic hurricane season has also much quiter than normal to date.

The fall is expected to be warmer-than-normal in Montreal, along with less precipitation. Winter will be challenging. Historically El Nino winters produce warmer temperatures along with less snow, but moisture latent southern systems tend to still produce heavy precipitation to the St. Lawrence Valley. This often results in freezing rain or mixed precipitation for Montreal. The great Ice Storm of 1998 occurred during an El Nino winter. Time will tell