Spectacular Harvest Moon Friday night in Montreal

The full Harvest Moon rises over the St. Lawrence Seaway in September 2015. (ValleyWeather Photo)

Another chilly morning greeted early risers on Friday, as temperatures settled into the middle single digits across southern Quebec, 6C (43F) here on L'Ile Perrot. Some locations across the Adirondacks and Laurentians dropped very close to the freezing point, with scattered frost reported. We can expect another sunny day, with seasonable temperatures of 22C (72F) here in Montreal. The weekend is looking unsettled, as a moisture-laden frontal system approaches Quebec form the Great Lakes. We can expect increasing clouds Saturday, followed by showers and thunderstorms through Sunday. Temperatures will be rather mild, with highs in the middle 20s and lows in the teens. Winds will be gusty both days this weekend.

HARVEST MOON
The Harvest Moon is the full moon closest to the Autumnal Equinox. Fall arrives on September 22 at 10:21a.m. ET, making Friday night's full moon this years harvest moon. The Harvest Moon has always been the biggest, brightest and earliest-rising full moon in the sky all year long, appearing shortly after sunset. Through the year's, farmers have relied on that moonlight to lengthen the short work days of late summer and early fall, allowing them to continue with the harvest late into the night.

This year, some will be treated to an additional celestial show. The full Harvest Moon will also feature a Penumbral Lunar Eclipse. While not as spectacular as the full lunar eclipse in September 2015, it should still be a sight to see. The moon will take on a spooky glazed look as it passes through the Earth's shadow. While conditions will be clear in eastern Canada, the eclipse happens early in the day and will not be visible here in Montreal. The full moon rises at 7:12 p.m. in Montreal. The eclipse will be visible across Europe, Africa, Asia, Australia and the Western Pacific. It will last 3 hours and 59 minutes, reaching its peak at 18:54 UTC (2:54 p.m. in Montreal).

A touch of fall in the air for Ontario and Quebec

A tree crushes a car in north end Montreal early Sunday morning. (CTV News Montreal)

Monday morning Southern Quebec awoke to a fresh air mass and the coldest temperatures since last May, 9C (48F) here on L'Ile Perrot. This comes after an active weather weekend across eastern Canada. Saturday was extremely humid, with summer-like temperatures rising into the high 20s and, in some cases, over 30C. Combined with the humidity, the atmosphere was juiced as a strong cold front arrived overnight into Sunday. The front generated widespread severe thunderstorms that swept across the St. Lawrence Valley from Kingston to Montreal and northeast towards the Saguenay. Winds gusted in excess of 70km/h in Kingston and Brockville, with a 69km/h gust reported at Trudeau Airport in Montreal. The wind toppled numerous trees onto cars and homes. Power lines were also damaged, with 60,000 Hydro Quebec customers across the province without power at the height of the storm. Over 150 crews and contractors worked through Sunday restoring power. As a result less than 1000 customers remain in the dark as of Monday morning. The thunderstorms also produced spectacular lightning in and around Montreal through the wee hours of Sunday morning, with over 30 strikes per minute in some cases. Funnel clouds were observed in southeastern Ontario, prompting a tornado watch.

A spectacular shot, taken by Kingston Police, of  lightning accompanying one of the storms Saturday night in Kingston, Ontario.

The front ushered in the first real fall-feeling air mass of the season. Temperatures remained in the teens on Sunday here in Montreal, along with a brisk northwest wind. This morning, skies are clear and it is fresh to say the least. The temperature dropped to 11C (52F) at Trudeau Airport, 9C (49F) here in Vaudreuil/Dorion, but as cold as 3C (39F) across the Laurentians and Adirondacks. The start of the week will be perfect, with lots of sunshine, low humidity and temperatures in the middle 20s. Clouds, along with showers and thunderstorms, arrive Wednesday, before conditions improve Thursday. Temperatures will cool once again to end the week.

Late-summer eastern heatwave

Tropical depression Hermine continues to dissipate off the east coast, while warm and humid air flows north into eastern Canada. (AccuWeather Map)

It feels like mid-August this morning in southern Quebec, with the current temperature already higher than our normal daytime high for early September. Montreal is currently 22C (72F), on our way to a high of 28C (83F). The overnight low was 21C (70F), over 10 degrees Celsius above normal. It is very muggy out after 4.2mm of rain overnight. Wednesday was sunny and hot across most of eastern Canada, from Ontario to Newfoundland. Montreal was nearly 30C (86F), while Toronto set a new high temperature record for the date at 35C (95F). The previous record dates back to 1960 at 33.9C (94F). New high temperature records were also established right across Atlantic Canada, including Newfoundland. Badger, Newfoundland recorded a new record high of 27.4C (81F). In Grand Manan, New Brunswick, the mercury hit 25.3C (78F) to tie the record for the date. Data at that location dates back to 1883, so this is significant warmth we are experiencing for September.

The webcam at Sunshine Village near Banff, Alberta, shows an early-season snowfall on Wednesday. (skibanff.com)

For those looking for cooler fall weather, you may have to wait another week or so, or travel to western Canada. Low pressure and a cold front will give Montreal a breezy, muggy day today, with showers and thunderstorms. Skies will clear briefly on Friday, but the weather will remain warm and a little humid. Another round of showers and thunderstorms is likely Saturday afternoon into Sunday, before high pressure returns. Sunshine will prevail to start next week. Temperatures in Montreal next week should remain well above the normal high of 21C (70F) and normal low of 10C (50F). The current heatwave covers most of the eastern United States as well, with high temperatures in the upper 80s and 90s and heat index values above 100F (37C) from the deep south into New England.

Meanwhile it is much cooler out west. Snow fell on Wednesday at Sunshine Village near Banff, as the temperature was just above the freezing point. More snow is possible next week, as a strong cold front is forecast to sweep the region.

Hermine blasts the Outer Banks - spares Jersey Shore

Major flooding was reported on Hatteras Island, North Carolina this past weekend from tropical storm Hermine. (TWC)

After hammering the Outer Banks of North Carolina through Sunday morning, Hermine is drifting slowly north this morning, 305 miles southeast of Long Island, New York. The Jersey Shore is breathing a cautious sigh of relief on this Labour Day Monday, having been spared so far. The storm continues to show signs of strengthening, currently with 70mph winds. Tropical storm warnings are posted for the Long Island coast, as well as eastern Massachusetts. High surf advisories are posted northwards into New Hampshire and Maine. Interests in Nova Scotia and coastal New Brunswick should continue to monitor Hermine.

Highway 12 on Hatteras Island, North Carolina, under water on Saturday, September 3. (AP Photo)

This storm has been difficult to forecast since day one. Hermine is expected to meander off the east coast through at least Wednesday, before moving northeast, south of Atlantic Canada, and out to sea. The threat for heavy surf continues today for the northeast US coastline from Delaware to Maine, but little inland effects are expected at this time. The catastrophic flooding forecast for the Jersey Shore has not materialized at this time. However there is still a risk of high surf and flooding at each high tide through mid-week from New Jersey northward. Residents are urged to continue to monitor this fickle storm.

Hermine is blamed for at least two deaths, one in Florida and a second on the Outer Banks. The storm blasted the Outer Banks on Saturday, with winds in excess of 80mph and severe flooding. Water was 5 feet deep in several villages on Hatteras Island after the Pamlico Sound spilled onto the island on the back side of Hermine. Roads were submerged and homes and businesses took on water. Conditions are slowly improving on the Outer Banks today, as crews begin yet another major clean-up of coastal Highway 12. Further north, dunes were destroyed in Nags Head and Kitty Hawk, with severe beach erosion reported.

Montreal
Meanwhile, the weather is perfect here in southern Quebec. What you see is basically what you can expect through mid-week. Strong high pressure is keeping Hermine off the coast, providing spectacular sunshine and warm temperatures in the upper 20s. This is followed by cool, crisp nights, with lows in the lower teens.

Hermine expected to batter US east coast for days

Hurricane Hermine caused major damage along the Florida Gulf Coast Friday morning before moving north into the Carolinas. (TWC/Getty Images)

Tropical Storm Hermine is going to be kept at bay to our south this weekend, by strong high pressure centered over Quebec. That high pressure will provide sunny, tranquil weather for southern Quebec and northern New England. Further south along the southern New England and Mid-Atlantic coasts, it will be a very different story.

This morning, Hermine is located 60 miles west northwest of Hatteras, North Carolina. The Outer Banks took a beating overnight, with heavy rain, in excess of 125mm (5 inches), as well as 60 mph winds and pounding surf. A tornado was reported on Hatteras Island, damaging a campground with minor injuries reported. From Florida to Virginia, hundreds of thousands are without power. So far one fatality has been reported from Hermine. Tropical storm Hermine is expected to move off the coast back into the open waters of the Atlantic later today. The storm will undergo some rather technical transformations over the next 24 hours, however she will remain a very dangerous storm. With the lessons learned from Hurricane Sandy, the National Hurricane Center will continue to provide updates on the storm, regardless of whether she is tropical, post-tropical or extra-tropical.

The projected track of Hermine has her stalling off the Jersey Shore this weekend. (NHC)

Call her what you want, the coast from Delaware to Long Island will be hammered for days during successive high tide cycles. The fear is for Sandy-like damage to coastal infrastructure in many locations. This holds especially true for the Jersey Shore. The storm will meander off the coast through at least Tuesday and perhaps longer before being swept out to sea.

 I will provide frequent updates on Hermine throughout the holiday weekend via twitter @valleyweather2 and this blog. Stay safe.

Hurricane Hermine sweeps into Florida's Big Bend

Hurricane Hermine made landfall at 1:30am Friday morning near St. Marks, Florida. Damage is widespread in the Big Bend area of The Sunshine State. (NBC News)

A strengthening Hurricane Hermine roared into the Big Bend area of north Florida overnight, making landfall near St. Marks at 1:30am. The storm, which has been extremely difficult to predict, has now been downgraded to a tropical storm, 50 miles northeast of Tallahassee. Hermine leaves behind major damage and flooding along Florida's Gulf Coast from Tampa to Tallahassee. Early estimates place the storm surge at 9 feet as Hermine moved inland. Overnight winds gusted in excess of 80 mph along the coast, with isolated tornadoes. Numerous trees and power lines are down, with nearly 200,000 residents without power. Many roads have been closed as a result of flooding. Authorities had to rescue people early Friday morning who had attempted to ride out the storm along the coast. Remarkably, Hermine was the first hurricane to hit Florida since Wilma in 2005.

A spectacular image of a strengthening Hurricane Hermine (upper right) just prior to landfall in Florida early Friday morning. (NOAA)

Hermine is the little storm that could; Expected to become a tropical storm, a week ago, the system defied forecasters and remained as a depression well into the Gulf of Mexico, before turning abruptly north and rapidly intensifying on Thursday. Hermine is expected to remain a strong tropical storm with heavy rain and winds up to 70mph across the southeast and into the Middle Atlantic states this weekend. Weather warnings stretch from southern New Jersey to Florida. The storm may impact eastern Canadian weather next week, but it is too soon to determine exactly how far north she will go. Hermine is forecast to stall off the east coast near New Jersey next week.

Goodbye to meteorological summer

National Hurricane Center forecast map for soon-to-be tropical storm Hermine. The storm is forecast to impact Florida over the next 48 hours before heading up the east coast. (National Hurricane Center)

Today is the last day of the summer season as far as meteorologists are concerned. Thankfully, Mother Nature lingers a little behind, so we can still expect more summer weather here in Montreal, usually well into September. But the signs of autumn are there: the kids are back to school, leaves turning slightly, and longer, cooler nights producing heavy morning dew.

Looking back briefly at June through August, temperatures averaged above-normal values. Some locations in southern Quebec and New England are expected to show their warmest August on record. Until the middle of August, it was also a very dry summer in Montreal. That has changed in the last two weeks, with more rain falling this month than in the previous two combined. Overnight, Montreal added to the monthly total as scattered thunderstorms developed. More are possible later Wednesday, before we say goodbye to August. At this time, the long holiday weekend looks spectacular here in southern Quebec, sunny and seasonable, with high temperatures in the middle 20s.

Across North America, the weather has been extremely active of late. A powerful and rare summer low pressure area pounded Newfoundland Monday and Tuesday, with torrential rain and winds in excess of 130km/h. A wind gust to 121km/h in Twillingate was the strongest August wind on record for that community. The previous record was 107km/h, set in 2007. Strong thunderstorms this week have produced severe flash flooding in Ohio and parts of Colorado. Deep hail fell in Colorado Springs on Monday, requiring snow plows to clear the streets.

Satellite image of tropical depression 9, Wednesday morning over the Gulf of Mexico. This system is forecast to strengthen into tropical storm Hermine later today. (NOAA)

The Tropics
In the tropics, tropical depression 9 is still meandering in the Gulf of Mexico, 640km south of the Florida coast. This system is expected to strengthen into a tropical storm later Wednesday, and be named Hermine. Warnings are in effect for a portion of the big bend area of Florida, as well and the Atlantic coast northward into Georgia. Heavy rain, up to 300mm (12 inches), and 60mph winds are forecast over the next 24 to 36 hours. The storm is then expected to move back over Atlantic waters over Labor Day weekend. All interests up and down the east coast of the US into Atlantic Canada will need to pay close attention to the future path of this tropical storm. Further out in the open waters of the Atlantic, hurricane Gaston has become a major storm, with 115mph winds. Gaston is no threat to land at this time. Meanwhile in the Pacific Ocean, hurricanes Madeline and Lester are expected to pass dangerously close to Hawaii over the next 48 hours. Warnings are in place for Madeline, forecast to move just south of the Big Island early Thursday morning.

The 5th Anniversary of Hurricane Irene

Torrential rain consumed many villages in central and southern Vermont, including Quechee shown above. (NWS)

August 28th is the 5th anniversary of the multi-billion dollar Hurricane Irene arriving in Quebec. Irene had humble beginnings as a weak area of low pressure off the west coast of Africa. The storm was the 9th tropical system of 2011, becoming the first hurricane of the season. Irene would sweep across the Bahamas as a major Category 3 hurricane before weakening and heading for the east coast. Irene made the first of two landfalls on August 27, 2011 at Cape Lookout, North Carolina, as a high end Category 1 storm.

By the time Irene would rain herself out over Atlantic Canada, nearly eight million east coast homes would be without power, and insurable losses would approach US$10 billion. Irene would cause extensive damage to coastal North Carolina, with a storm surge washing over portions of the Outer Banks. The storm then moved inland southwest of New York City and tracked across Vermont and into the Eastern Townships of southern Quebec. Along her path torrential rain would fall, with as much as 250mm (9 inches) in less than 24 hours. The resulting flash flooding would heavily damage numerous villages and towns across the Catskills of New York and into the Green Mountains of Vermont. The flooding in Vermont would be the worst natural disaster in that state since the flood of 1927. In the end, 49 fatalities were attributed to the storm, including one in Quebec. The raging Yamaska River east of Montreal washed out a section of road, contributing to the drowning of a motorist.

A satellite image from August 28, 2011 shows Hurricane Irene engulfing New England and southern Quebec. (NOAA)

In Quebec, Irene produced as much as 150mm (6 inches) of rain in the Charlevoix region and sections of the Beauce and Townships. In Montreal, 65mm (2.5 inches) of rain fell in less than five hours. Winds gusted over 100km/h in Quebec, including a peak gust of 113km/h on Ile d'Orleans. In Montreal, the highest gust was 90km/h. The wind and rain contributed to power outages, with nearly 250,000 Quebec homes in the dark. The power at my home on l'Ile Perrot was out for over 20 hours. Final damage estimates in Quebec exceeded $130 million.

Irene was one of the first storms that tapped into the wave of social media. The storm threatened a large population along the east coast of the US, and was therefore heavily publicized. New York City was shut down for an entire weekend. In the end, many felt the storm was over-hyped. Unfortunately, this drew attention away from Vermont and upstate New York, where Irene was one of the worst natural disasters on record. Irene proved just how devastating a low-category hurricane can be, especially to inland locations.

The tropics are heating up

NOAA, National Hurricane Center image of Hurricane Gaston, and Invest 99-L (orange X) in the Atlantic basin. At this time, Invest 99-L has a better-than-even chance of becoming tropical storm Hermine. The storm could then impact south Florida as early as this weekend.

We are entering the most active period in the Atlantic hurricane season, which typically runs from June 1st to November 30th. Most of the storms occur within a six-week period from late August to early October, focused around Labor Day.

Forecasters at the National Hurricane Center in Miami, Florida are currently watching two systems in the Atlantic basin. Hurricane Gaston is a minimal storm with 75mph winds, located over 1000 miles east of the Leeward Islands, and not any threat to land. Gaston is expected to weaken over the next 24 hours as it moves into cooler waters. Of more interest this morning to forecasters and weather nerds alike, is an area of showers and thunderstorms dubbed Invest 99-L, just north of Puerto Rico. Depending on your weather model of choice, this low pressure area could become tropical storm Hermine this weekend and impact south Florida. Beyond that, different models are presenting very different scenarios. If the system develops, and that is still not certain, it could swing northeast out to sea, or impact the waterlogged central Gulf Coast as a strong storm next week.

In any event, I will be monitoring this storm closely, as I have been doing since 1979 when my interest in hurricanes started. Many of these storms impact eastern Canada with heavy rains and strong winds. Case in point: Hurricane Irene, whose 5th anniversary is coming up later this week. Irene generated over $1.5 million dollars in damage and one fatality in Quebec back in 2011. It was also the costliest natural disaster in Vermont state history. I will have much more on Irene later this week.

Autumn-like start to the week

Another spectacular warm and humid morning sky on L'Ile Perrot this past Friday, August 19. Summer will take a brief break today before returning Tuesday.

A wet and windy cold front on Sunday afternoon ushered in a brief taste of fall for southern Quebec. This morning temperatures are as cool as they have been at any time this month. It was 14C (56F) at 7am on L'Ile Perrot. The front also added to our quickly-recovering summer rainfall totals, with another 15 to 25mm falling on Sunday, 21.6mm here on L'Ile Perrot. That actually lifts us to close to normal precipitation since June 1st, with over 125mm (5 inches) falling in just the last week.

Today will be partly cloudy and fall-like, with a high temperature near 20C (68F) and very comfortable humidity levels. Clear skies tonight will allow for cool lows between 10C and 14C (50 to 55F) in southern Quebec. On Tuesday, warm southwest winds will return, along with high temperatures rising rapidly to 27C (81F). The balance of the week will see a return to warm and humid weather, with highs approaching 30C (86F) once again. The warm weather will last through Friday, before another cold front arrives with showers and thunderstorms. At this time next weekend looks sunny, warm and dry.

Record rainfall for Montreal

Torrential rain slowed the evening commute in Montreal. A record-setting 67mm fell on the city in less than five hours Tuesday night. (ValleyWX Photo)

Tropical rains fell across southern Quebec and Ontario late on Tuesday, with a record 67mm at Trudeau Airport in Dorval, most of that falling between 2pm and 9pm. That amount shattered the previous 24-hour record for August 16 of 49.5mm, established in 1966. It also rapidly brought the August total for the city from nothing to 119mm in just four days. The average August rainfall for Montreal is 94.1mm. Heavy rain and strong winds created widespread power outages across the region. As of early Wednesday morning, nearly 100,000 Hydro Quebec customers were in the dark. That number has since fallen to around 35,000 as of noon, August 17. Hydro Quebec has not specifically mentioned the cause, but a substation in Mercier-Hochelaga-Maisonneuve was flooded and knocked offline last evening.

The rain and poor visibility may have also contributed to accidents in which two pedestrians were struck by cars, in different parts of the city. Some underpasses were also flooded, but for the most part the water drained well. The ground has been parched lately and water levels have been very low, so the runoff was quick.

Other amounts of rain reported last evening included 58mm at my home on L'Ile Perrot, 77.8mm downtown at the McTavish recording station, 75mm at Oka, 90mm in Wiarton, Ontario, 58mm in Kemptville, Ontario and 26mm in Ottawa. South of the border in Vermont, heavy localized rain from thunderstorms washed out a section of Route 100 in Duxbury.

Warm and humid weather will now be with us through the weekend, with highs from 28 to 30C (83 to 86F) and warm lows near 20C (68F). The humidex readings will climb from the low to middle 30s by the weekend. Scattered thunderstorm activity is possible over the weekend, in the soupy air mass.

Heavy rain warning for Montreal

Heavy rain warnings have been posted for Ontario and Quebec. 
(AccuWeather.com map)

Widespread heavy rainfall warnings have been issued by Environment Canada for southern and eastern Ontario and southern Quebec. The same system that has created the devastating flooding in Louisiana will lift northeast across the Great Lakes and towards Quebec. The good news is that the system will be moving fairly quickly through our region. Rain will spread west to east across Ontario this morning and into Montreal later this afternoon. The rain will be heavy at times tonight, along with thunderstorms.

The death toll has risen to nine in Louisiana after nearly 25 inches of rain. Widespread historic flooding is occurring. The photo above is from Prairieville, Louisiana. (Photo via Twitter @presleygroupmk)

At this time, we can expect 40 to 60mm of rain across the region, with as much as 70mm locally. The heavy rain comes on the heels of the 50 to 100mm that fell over the weekend, however we are not expecting any major flooding. Southern Quebec and Ontario were bone dry for the past six weeks and water levels are very low. We should be able to absorb the new precipitation without incident. There may be some minor ponding of water in low-lying areas and on roadways. Temperatures will be rather warm and muggy, with a high of 25C (77F) today and 27C (81F) Wednesday. Overnight lows will be near 20C (68F). Skies will slowly clear in Montreal on Wednesday.

Heavy rain from Louisiana to Quebec and Ontario

Historic flooding across Louisiana has resulted in at least four fatalities and thousands of evacuations and water rescues. (Photo via Twitter @cbcnews)

What a difference a few hours can make when it comes to the weather. In less than 48 hours, many portions of southern Quebec and eastern Ontario recorded more rain than in the previous six weeks. Heavy tropical rains, along with embedded thunderstorms, swept along the edge of a large Bermuda high to our southeast. Southern Quebec reported 50 to 100mm (2 to 4 inches) of rain over the weekend, the heaviest along the Ottawa Valley, through Montreal and into the Townships. Here on L'Ile Perrot, I measured 78mm from late Friday to early Sunday. That included nearly 27mm in just a couple of hours, during a thunderstorm early Sunday morning. The normal monthly rainfall in August is 94.1mm for Montreal. Some severe weather was also observed, with tree damage in the eastern Townships, as well as minor flooding being reported. In Ontario, at least two tornadoes were confirmed on Saturday, including an EF-1 (150 to 175km/h winds) along the shores of Lake Simcoe.

LOUISIANA FLOODING
The soupy weather across eastern North America is the result of a large Bermuda high sitting off the east coast of the US. This system is pumping extremely warm and humid air north and west. Searing heat has been gripping the large east-coast cities of the US, as well as southern Ontario. We had a break on Saturday, as clouds and rain managed to keep the temperatures down here in Montreal. Along the edge of the high is a conveyor belt of moisture running from the Gulf of Mexico into Quebec. Therefore the closer to the Gulf, the more rainfall. Unprecedented historic flooding is occurring in Louisiana, with a least four fatalities reported. Thousands of water rescues have occurred, in addition to tens of thousands more evacuated. The flooding was the result of nearly 2 feet of rain in less than 48 hours. Damage is widespread across the state, including the closure of Interstate 10.

After the severe drought conditions of the last month, more rain is expected in southern Quebec late Tuesday and Wednesday, with perhaps another 25 to 50mm. Temperatures will warm up again for Monday, reaching 28C (83F) this afternoon in Montreal.

Much needed rain this weekend

Tropical moisture may help alleviate some of the drought conditions in Ontario and Quebec this weekend. (AccuWeather.com Map)

7AM Friday Morning Update: A few weak thunderstorms this morning deposited a few millimetres of rain on L'Ile Perrot and Montreal. This was the first precipitation in 18 days. More rain is expected this weekend, possibly heavy at times. A flood watch is in effect for northern New York and Vermont. The same conditions prompting that watch state side, will exist in southern Quebec, with 25 to 75mm (1 to 3 inches) of rain possible through Sunday. Temperatures will be warm all weekend, in the middle 20s, and it will be very muggy.

Previous post below:
It remains hot and humid across eastern Canada this week, but with no rain here in southern Quebec. The last rainfall in Montreal was way back on July 25th. Hot weather has returned this week, with daytime high temperatures well into the 30s on Wednesday. Montreal fell just shy of the 1944 record of 32.8C (91F), with a high of 32.5C (91F) recorded at Trudeau Airport. Ottawa reached 35C (95F), and Toronto a scorching 36C (97F).

Thursday will feature the exact same weather, but more oppressive, as humidity levels rise. Overnight temperatures in Montreal remained uncomfortable, in the low-to-middle 20s, with highs today expected to reach the low-to-middle 30s. Combined with the humidity, the humidex or real feel temperatures will reach 40C (104F). Starting Friday, deep tropical moisture will lift north from the Gulf of Mexico. As it interacts with a front over eastern Canada, heavy rainfall is possible. The rain will come in waves, along with very muggy temperatures. Expect showers and thunderstorms from Friday through Sunday. It will not rain all the time, but when it does, it could be rather heavy at times, with some local flooding. The possibility exists for 25mm to as much as 75mm of rainfall in some locations across eastern Ontario, southern Quebec and New England. The rain will be beneficial to the moisture-starved vegetation. Temperatures will remain warm, but not as warm as we have experienced, due to thick cloud cover. Highs in Montreal will range in the middle 20s, with lows in the upper teens.

Drought conditions worsen in Quebec and Ontario

Southwest Quebec is experiencing moderate-to-severe drought conditions. It has not rained in two weeks. (plantmaps.com)

You cannot understate how dry the weather has been across southern Quebec and Ontario. According to the most recent data, most of southern Quebec is either abnormally dry or in a moderate drought. The far southwest, including L'Ile Perrot, Hudson, Valleyfield, northwest towards the Ottawa Valley, is currently showing as being under a severe drought. As you travel further southwest into Ontario, conditions are even worse, ranging from severe to extreme drought, including Toronto.

Similar conditions are occurring across southwest and eastern Ontario as well. This map is from early July. The situation has since become extreme in portions of the GTA. (Agriculture Canada)

We need rain! The last measurable rainfall at Trudeau Airport in Montreal was 5.8mm on July 25. Cumulative rainfall for the summer season so far is running at 40 to 50 percent of normal for Montreal. Ottawa has recorded even less rainfall. Couple that with the prolonged stretches of hot weather, and you have the recipe for drought. On Friday, Montreal recorded one of the warmest days of the summer at 34C (93C). This established a new record high for the date, surpassing 32.9C (91F) from 1988. More heat is forecast this week, with the mercury expected to reach the upper 20s today and low-to-middle 30s the balance of the week. Forecasters are watching the weekend for perhaps the most significant amount of rain so far this summer for Montreal. A moisture-laden storm system may move close enough to the St. Lawrence Valley, by Friday. That event is several days away, so we will have to wait and see how the system plays out.

In the meantime, conserve water. The signs of heat stress are widespread. Most of the lawns on L'Ile Perrot look like hay, the plants are wilting and numerous trees are starting to shed their leaves. Additionally, water levels on area lakes and streams are very low. Use caution when boating.

Slightly cooler, less humid weekend for Montreal

With temperatures into the low 30s, by the lake in Pointe Claire was one of the few spots you could cool off naturally this past week. (ValleyWeather)

Thursday was another hot day in Montreal, as the temperature nudged above 32C (90F) once again. We can expect the same today, along with elevated humidity levels. The forecast high should range from 31 to 33C (88 to 92F). A strong cold front will arrive across eastern and southern Ontario this afternoon, advancing into southern Quebec tonight. Along the front, strong thunderstorms are forecast to develop in Ontario this afternoon. As the front moves into our region, we can expect a round of showers and storms as well, but I think their strength may diminish here in Quebec. The reason for this is that the front should arrive in Montreal after the warmest part of the day, allowing for more stability in the atmosphere. We will have to watch this scenario, as warnings may be needed for a portion of the region.

Behind the front, cooler air will arrive, along with lowering humidity levels. Saturday will be unsettled to start the day, with some showers around Montreal, but partial sunshine by afternoon. Temperatures will be much cooler this weekend, around 25C (77F). Fair weather is expected to start next week with perhaps showers by Wednesday. Temperatures will warm again into the upper 20s.

Active severe weather continues to be widespread across North America this summer. Since Sunday, nearly a dozen tornadoes have been reported across the northern plains into southern Saskatchewan and Manitoba. At least five have occurred on the Canadian side of the border. Winds in excess of 100km/h, heavy rain and large hail were reported in Manitoba on Wednesday.

The tropics are beginning to awaken as well. Hurricane Earl moved into Belize on Thursday, with heavy rain and 120km/h winds. Earl is close to the Bay of Campeche this morning, and is forecast to weaken further as the system slides into mainland Mexico. Heavy rain, up to 300mm, is possible along the path of the storm. National Hurricane Center forecasters are watching other areas of the Caribbean Sea and Atlantic for further development next week.

July 2016 into the history books

This tornado south of Yorkton, Saskatchewan, destroyed one home on Sunday afternoon. (Twitter Photo @katielyn_213)

My favorite month of the year is over, sadly. July in Montreal lived up to expectations as the warmest and most humid month of the year. This July featured lots of sunshine and below-normal precipitation. The rain that did fall was associated with thunderstorms, and thus highly variable across southern Quebec. Officially at Trudeau Airport, 74.2mm of rain fell, below the normal of 89.3mm. I recorded 79mm here on L'Ile Perrot, but almost half of that fell in one thunderstorm. As far as temperatures go, it was warm, with an average daily high of 27.2C (81F), above the long-term average of 26.3C (79F). The average overnight low for the month was 16.8C (63F), also above the normal of 16.1C (61F). The warmest high temperature was 33.7C (93F) at Trudeau, 35C (95F) here on L'Ile Perrot. We managed six days above 30C, with another four days very close, above 29C.

August has started off the same way. This week is expected to be warm, with increasing humidity. High temperatures will be from 28C to 32C (83 to 90F) as the week progresses. A strong cold front will arrive by late Friday, with showers and thunderstorms. At this time, the weekend looks less humid and slightly cooler. Some of you may have noticed a few trees dropping their leaves. This is very early, and likely caused by the very warm and dry July. Heat stress on trees will often manifest itself that way. That being said, we will start to loose daylight rapidly this month, increasing the leaf-shedding process naturally as we head into September.

TORNADO
We had another weekend of severe weather across many portions of North America. Most notable were the two strong tornadoes that occurred between Yorkton and Melville in Saskatchewan on Sunday. Thankfully, no injuries were reported, but widespread damage did occur. One home and farm was completely destroyed. Along the east coast of the United States, the story was flooding. Over 150mm of rain in less than two hours sent torrents of water rushing through Ellicott City, Maryland. The historic town, west of Baltimore, was left in ruins, with two fatalities reported.

Large hail pounds the Saguenay region of Quebec

Widespread damage occurred in the Saguenay region of Quebec on Wednesday, after baseball-size hail pounded the area. (TWN Photo courtesy Anne-Julie Belley)

 A fierce hailstorm caused widespread damage across the Saguenay region of Quebec on Wednesday, July 27. Hail as large as 8cm in diameter fell in L'Anse-Saint-Jean, 2 to 5cm in La Baie and 2 to 4cm in Bagotville. The hail was part of a series of severe thunderstorms that swept across most of central and eastern Quebec, as well as northern Maine and New Brunswick. The storms were fueled by persistent hot and humid weather. Strong winds also accompanied the thunderstorm cells, knocking down trees and power lines. Widespread damage to homes and cars was reported as a result of the hail.

HOW DOES HAIL FORM?
Hail develops when strong updrafts in thunderstorms carry raindrops high into extremely cold regions of the atmosphere. Typically the storms in question are towering in nature, with cloud heights in excess of 30,000 feet. The raindrops freeze into balls of ice. The hailstone grows by colliding with super-cooled water droplets in the cloud. These freeze on contact with the evolving hailstone. The hail will be lifted multiple times into the upper portion of the thunderstorm, adding a layer of ice each time. Hail falls to the ground when the ice becomes too heavy for the updraft to maintain it, or the updraft weakens. Hail can be driven into the ground, cars, homes and people, by very strong winds that accompany the thunderstorm. The more severe the storm, the larger the hail. The hail can also merge with other stones, creating awkward and dangerous shapes. Hail has been know to cause widespread million-dollar damage. The largest hailstone reported in the US was in Vivian, South Dakota on June 23, 2010. It was 8 inches (20cm) in diameter, weighing in at 1 pound 15 ounces (878 grams). In Canada, the largest stone fell at Cedoux, Saskatchewan, on August 27, 1973. The hailstone was 11.4cm in diameter (4.5 inches), and weighed 290 grams (0.6 pounds).

Hail can damage windows and rip the siding from homes. (NOAA Photo)

Montreal often records small hail during summer storms. However, on May 29th, 1986, and on the same date in 1987, the city had major hailstorms. The hail measured up to 8cm (3 inches) in diameter and destroyed numerous trees and gardens. Damage was reported to homes and cars as well. The 1986 storm alone produced estimated insurable losses in excess of $70 million. I lived in southern Saskatchewan from 1997 to 2000 and witnessed many large hailstorms. One particular storm in 1998, left the roads covered in deep hail, and also damaged my car. It was before the digital era, so the photo lives in a box somewhere... and I will find it someday.

Lightning really does strike the same place twice

Like a giant lightning rod, the CN Tower in Toronto is struck 75 to 80 times each year. (blogTO Photo)

6:30 AM: Another warm and humid day is forecast for Montreal today, with a high of 28C (83F), along with scattered thunderstorms.

It is often said that lightning will not strike the same place twice. This is a rather important and life- threatening myth. Over the weekend, a picture of the Empire State Building in New York City being struck by lightning was circulating on social media. It got me thinking, how often does such a tall building get struck? The answer is 25 lightning strikes, on average, each year, up to as many as 100 times. The CN Tower in Toronto, being taller, is struck an incredible 75 to 80 times each year. A series of 52 grounding rods, running the length of the building and six metres below the surface, prevents the structure from being damaged. Each rod is 56cm thick. For the most part, the strikes are spread out over the thunderstorm season. However, on August 24, 2011, the CN Tower was struck 52 times in less than 90 minutes. So as you can very well see, lightning can and does strike the same location often.

This video-still of the Empire State Building being struck by lightning was taken by a tourist on July 23. (Weather.com)

Several weeks ago, I wrote about lightning safety so I won't go into that here. Simply put, there is no safe place outdoors. When thunder roars, go indoors. We are half-way through what has been a hot and humid summer across most of North America, with frequent thunderstorms. Lightning-strike data is rather difficult to come by in Canada, but the United States has already recorded 21 fatalities. Sadly, this puts them on a pace to achieving a much higher total than that of the last few years. Since 2008, the message had been getting out, with fatalities down from nearly 50 annually to under 30. Here in Canada, we average 10 fatalities a year, along with multiple injuries. The problem is a global concern. Just last month, within a few days, over 80 people were killed from lightning strikes during monsoon rains across India.

Another round of thunderstorms for Montreal

Rapidly developing thunderstorms produced torrential rain and flooding on L'Ile Perrot, Saturday, July 23. (ValleyWX)

Hot and humid weather took a one-day break on Sunday after Saturday's wicked weather. Strong thunderstorms rapidly developed on Saturday afternoon north of Montreal, and moved southeast across southern Quebec and into upstate New York and Vermont. The storms produced 25mm (1 inch) of rain here on L'Ile Perrot in under one hour. The result was flooding on numerous roads. Such was the case as well across other parts of Montreal. Some roads, especially ramps and viaducts on and off Highway 40, had to be closed until the water receded. The same cluster of storms dropped hail up to 2cm and produced winds in excess of 100km/h across Valleyfield and Vaudreuil and south of the city into the Townships. Tornado warnings were even issued southeast of Montreal, with several of the storms showing signs of rotation. Numerous trees and power lines were knocked down. South of the border, strong winds left several boaters requiring rescue on Lake Champlain. The wind also knocked out power to thousands in Vermont, some still in the dark this morning. One fatality was reported in Vermont.

Searing heat and humidity across a wide portion of Canada this July has resulted in numerous rounds of severe thunderstorms. The photo above is from my good friend in Moose Jaw, Saskatchewan (Dayna Smith-Short)

This morning, the heat and humidity are building once again, as a warm front approaches from Ontario. Showers and isolated thunder will give way to partly sunny and muggy weather through mid-afternoon. Temperatures will rise rapidly to around 30C (86F). A cold front will cross the area late in the day, with another round of robust thunderstorms. Some of the storms, like Saturday, may have heavy rain and small hail. Skies should clear after midnight, with a warm and dry Tuesday expected. The low tonight will be around 20C (68F), with the high Tuesday near 27C (81F).

Another sultry summer day for Montreal and Ottawa Valley

The heatwave in the central portion of the United States continues to periodically spill into Ontario and Quebec.

Heat warnings and special weather statements remain in effect from Environment Canada for southern Ontario and Quebec today. The combination of very warm temperatures, along with the high humidity, is creating rather steamy weather from Montreal to Ottawa and Toronto. Temperatures on Thursday reached the low to middle 30's across many location of eastern Canada including 31C (88F), here in Montreal, and 34C (94F) in Toronto. A few showers and thunderstorms overnight in Quebec only added to the elevated humidity. The temperature dropped no lower than 22C (72F) early Friday morning in Montreal, and we are already up to 27C (80F) as of 9:30 here on L'Ile Perrot.

Giant baseball size hailstones fell in central Saskatchewan this past week. A tornado was also reported near Davidson, Saskatchewan on Tuesday, July 19. (CBC Saskatchewan)

What you see is pretty much what you get, as southern Quebec will remain on the northern edge of a ring of fire in the central US. A massive dome of hot high pressure remains centered over the Midwest, with a rather strong and prolonged heatwave underway there. Temperatures in those regions have been in the 90's to 100F (34 to 37C). Along the edge of this system are periodic ripples of low pressure and frontal boundaries giving a break from the heat, but also showers and thunderstorms. Some of the storms have been very strong, with large hail and even tornadoes reported in Saskatchewan and Manitoba this week. Some thunderstorm activity is possible in Montreal later today and Saturday. Sunday is expected to be fair at this time, and a touch cooler. We can expect more heat and humidity next week with daytime highs very close to 30C (86F) each day for Montreal and southern Quebec.

Hot and stormy July continues

More strong thunderstorms are expected Monday afternoon across extreme eastern Ontario and southern Quebec.

Strong thunderstorms are possible in eastern Ontario and southwest Quebec today from 12 noon through 8pm. A severe thunderstorm watch may be needed later this morning.

Temperatures are on the upswing today following a dry and cooler weekend. A warm front has already lifted north across the St. Lawrence Valley this morning with scattered showers. The humidity will build in quickly, with high temperatures near 28C (83F). The humidex reading will rise into the upper 30's. The air mass will quickly become unstable, with strong thunderstorms likely in Montreal by mid to late afternoon. Some of the storms could produce very strong winds, small hail and heavy downpours. The storms will develop by late morning in Ontario, ahead of a trough and cold front, before moving into Quebec and New York State.

A strong gust front and thunderstorm approach L'Ile Perrot around 6pm Friday night. The storm produced winds in excess of 90km/h, knocking down trees and power lines in several west end suburbs. (Valley Weather Photo)

The setup is very similar to Friday when L'Ile Perrot and the southern portion of Montreal island were hit by a rather strong storm around 6pm. Sweeping from west to east, the storm produced winds up to 90km/h. Numerous tress were brought down, especially along south facing shorelines. Power outages were widespread, adding to the workload of Hydro Quebec, still trying to restore power from Thursdays thunderstorms.

Today's front front clears the region overnight Monday, with a partly cloudy, less humid, and cool day Tuesday. The high temperature will be near 22C (72F). After the one day break, the heat will begin building again Wednesday, reaching into the low 30's (up to 90F) by next weekend. We can also expect an increase once again in the humidity and the likelihood of more thunderstorms.

More storms to end the week

Hot and humid weather generated thunderstorms this week. As a result widespread tree damage and power outages occurred in many portions of Quebec, including Quebec City, shown above.

Severe Thunderstorm Watch in effect for southern and western Quebec through sunset Friday.

Montreal is under a set of new severe thunderstorm watches late this afternoon as a second cold front approaches the region. Strong storms are flaring up across the Ottawa Valley and moving into western Quebec. These storms come on the heels of those Thursday evening that downed trees and cut power to thousands of Quebec homes. Particularly hard hit was the region of Vaudreuil/Soulanges west of Montreal. A strong storm near midnight produced winds in excess of 70km/h in Vaudreuil and on L'Ile Perrot. Hydro Quebec crews have been working since then to restore power, with 15,000 clients still in the dark.

Once the thunderstorms end this evening, we can expect cooler weather into Saturday with a few showers. The temperature approached 30C (86F) once again Friday, but will lower to 23C (73F) Saturday, and 26C (79F) Sunday. Sunday will be the better of the two days with nothing but sunshine forecast.

Record heat for Montreal - strong storms today

The Dairy Queen along Highway 20 on L'Ile Perrot provides the foreground to developing thunderstorms on the horizon. (ValleyWX)

A heat warning remains in effect today. We have an elevated risk of strong thunderstorms as well.

Searing heat surged into southern Quebec on Wednesday, with Montreal squeezing out a record high of 33.7C (93F). (The previous record was 33.6C, set in 1987, the heatwave just prior to the famous Decarie Expressway flood). The warm temperatures lasted into the overnight, with the 6am temperature already at 24C (76F) in Montreal. Other parts of the region were also warm on Wednesday, with 35C (95F) in Vaudreuil and here on L'Ile Perrot. Ontario was hot as well, with Toronto being the warmest in the country at a record-setting 36C (97F). This broke the previous record of 34.9C set in 2005. The 35C I recorded on my Davis Vantage Vue is the warmest reading I've observed on L'Ile Perrot, since moving here in 2009.

The heat, combined with elevated humidity readings, produced humidex temperatures into the low 40s. It was oppressive for any outdoor activities. Relief is on the way today in the form of a cold front, which is draped across Ontario this morning. The front will generate some drenching, slow-moving thunderstorms today. The storms are expected to reach southern Quebec early this afternoon. Some of the storms may produce flooding rains and strong winds. Overnight, the same cold front produced a line of thunderstorms that brought winds in excess of 90km/h to Toronto.

Today will be warm once again for southern Quebec, with highs near 30C (86F). It will remain muggy overnight, with lows near 21C (70F). Friday will be a touch cooler at 27C (81F), with some showers around. As of now the weekend looks decent, with some spotty showers Saturday, but clearing out late in the day and a high near 25C (77F). Expect sunshine on Sunday, with a daytime high near 27C (81F).

Heat and humidity build into eastern Canada this week

A surge of hot and humid air will move into southern Ontario and Quebec this week, with forecast high temperatures over 32C (90F) in Montreal, Ottawa and Toronto.

After a dismal weekend, with solid cloud cover and occasional rain, the region is looking at clearing skies this morning. Around 20mm of rain fell in southern Quebec on Saturday and early Sunday, as low pressure skirted down the St. Lawrence Valley and into New Brunswick. Skies are clearing this morning, with patchy fog and warming temperatures. The clouds and rain kept temperatures cool, near 20C (68F) all weekend, well below the normal high of 26C (79F).

Heatwave?
In Montreal, a heatwave is usually declared when high temperatures reach or exceed 30C (86F) over three consecutive days. However, the official Environment Canada definition is three days over 32C (90F). A heat advisory is posted when the humidex value, the combination of heat and humidity, is expected to be near 40C or higher. It's all relative. However you want to look at it, it will be a very hot and sticky week. High pressure will build into Quebec today, cresting over us tonight and sliding to our east on Tuesday. As the center moves east, a rather potent surge of heat and humidity will move into the Great Lakes Basin and St. Lawrence Valley. High temperatures will be on the rise in Montreal, from 26C (79F) today, up to the low 30s (near 90F) by Wednesday. The humidity will build as well, with humidex readings approaching 40C (104F) in southern Ontario and Quebec by Wednesday afternoon. Environment Canada has posted a special weather statement for Montreal, Ottawa and Toronto regarding the potential heatwave this week. Heat warnings or advisories may be needed for several metropolitan areas by mid-week. Overnight low temperatures will become rather uncomfortable as well, remaining in the low 20s (low 70s). The heat will also provide the fuel for pop-up thunderstorms each afternoon from Wednesday to Friday. Some storms may be on the strong to severe side, especially Friday. Relief will come from the heat in the form of a cold front by late in the week. Next weekend at this time looks ideal, with low humidity, sunshine and warm temperatures.

Wet weekend ahead for Ontario and Quebec

Southwestern Quebec, along with southern Ontario, continues to be exceptionally dry. The Environment Canada map above shows that some areas had as much as 75 to 90 percent less precipitation than normal for June 2016.

We need the rain. That being said, the timing is less than perfect with the weekend approaching. Montreal continues to run at a significant deficit as far as precipitation is concerned. Officially, only 6.6mm of rain has fallen in Montreal for July. This follows a very dry spring with precipitation amounts running at 25 to 50 percent of the normal in southwestern Quebec. The effects of the limited rainfall can be seen on lawns all over the region. Additionally, water levels are very low on area lakes and rivers. As well several trees are beginning to lose leaves, a sure sign of loss of water and heat stress. The only saving grace has been the cooler nights. It has been an odd summer so far. As far as high temperatures go, Montreal has already reached 30C (86F) or higher on 8 occasions in 2016. We managed this only 11 times during the entire summer of 2015. The heat however has been punctuated by days of very cold weather for summer in Montreal. On Thursday, a weak frontal boundary, located just south of Montreal, resulted in the city having light northeast winds and a high of only 25C (77F). Areas just off-island to the south and west of the city were in the upper 20s, even into the low 30s in some cases. Strong thunderstorms affected northeast New York and northern Vermont, with hail, downed trees and power outages during the afternoon and evening.

That brings us to this weekend. Multiple areas of low pressure will impact Ontario and Quebec, as they slowly move northeast into Atlantic Canada. After a partly cloudy and humid Friday, with a high near 26C (79F), clouds will be on the increase tonight. Showers and thunderstorms will develop overnight and continue intermittently on Saturday. Gusty winds up to 50km/h will help keep temperatures cooler Saturday and Sunday, around 20C (68F) in Montreal. The weekend rainfall is expected to drop 25-35mm (1 to 1.5 inches) on the region. On Monday, skies will slowly clear out. We are expecting a return to very warm and increasingly humid weather by early next week, with high temperatures once again approaching 30C.

Unsettled and humid week ahead for Montreal

We can expect a spike in the humidity through the middle portion of this week. Temperatures will feel like the middle 30's in Montreal.

High pressure is in control of the weather this morning in Montreal and across New England and eastern Ontario. Temperatures cooled rapidly last evening after sunset but are already warming up this morning. The overnight low here on L'Ile Perrot was 14C (56F), after a daytime high Monday of 29C (85F). We can expect similar weather today, with bright sunshine, perhaps some afternoon cloudy periods and a high near 31C (88F).

On Wednesday, there will be a noticeable increase in humidity, that will likely be with us for the balance of the week. The temperature will be warm once again to 30C (86F). As a result of the spike in humidity, conditions will be a little uncomfortable with humidex readings in the upper 30's for Montreal and close to 40C over southern New England. Showers and thunderstorms will develop late Wednesday and especially Thursday as the front and low pressure system move east across southern Quebec. Some of the thunderstorms may produce heavy rainfall as they develop in Ontario and spread east into Quebec. Unfortunately at this time, it looks like the clouds and showers will be with us into the upcoming weekend, along with a drop in temperatures into the middle 20's.

Mother Nature provides the fireworks for Canada Day

Happy Canada Day. Clouds will increase across southern Quebec today with thunderstorms likely this evening. 

High pressure is in control of the weather across southern Quebec this morning. After a very pleasant Thursday, Canada Day Friday is shaping up to be sunny and warm with a high temperature near 28C (83F) for Montreal. A rather vigorous cold front over the Great Lakes will sweep into the St. Lawrence Valley this afternoon and evening along with showers and thunderstorms. Like Tuesday afternoon, some of the storms may be locally severe with gusty winds, small hail and heavy rain possible. The thunderstorms on Tuesday produced severe weather in extreme southern Quebec with 100km/h winds reported along the US border in Huntingdon. Strong storms also affected Morin Heights where trees were toppled, and 17,000 Hydro Quebec customers left without power. In Montreal, and here on L'Ile Perrot, we had lots of lightning and much needed rainfall, with 12 to 20mm reported.

Today's storms will develop over Eastern Ontario and the Adirondacks of New York early in the afternoon and move rapidly northeast into southern Quebec by 4 or 5pm. Severe thunderstorm watches may be likely for part of the region late today, so have an eye on the sky as you take part in the many scheduled Canada Day activities. The showers will taper off after midnight as cooler air arrives from the west. Overnight lows will drop into the upper teens, with a high on Saturday near 21C (70F). Saturday  will be partly cloudy, with some showers still around. High pressure arrives Sunday with sunshine and dry weather expected to last well into next week. Temperatures will warm daily from 26C (79F) Sunday, up to 30C (86F) by the middle of next week.

Funnel cloud and possible tornado near Ponoka, Alberta late Thursday afternoon (CBC News)

Alberta Tornado
Strong thunderstorms swept across central Alberta on Thursday, with hail, fierce winds and possible tornadoes. One funnel clouds produced damage near Ponoka, Alberta south of Edmonton, just missing a packed fairground. No injuries were reported. Environment Canada will be investigating the damage today to determine if a tornado did touch down.

Strong thunderstorms possible for southern Quebec

Montreal remains abnormally dry, with most vegetation now showing some signs of heat stress and lack of water. Southern Ontario and parts of the Northeast US are in a moderate drought. (AccuWeather)

Our current stretch of warm and humid weather is about to come to an end. Twin cold fronts lie just to the northwest of Montreal this morning, with showers and thunderstorms expected to develop along them today. Some of the storms may be strong to locally severe, with heavy rain, gusty winds and small hail possible, especially from Montreal south and east into the Townships and New England. Thunderstorms are forecast to develop around noon in Montreal and last through sunset.

Montreal is very warm this morning, with a mild overnight low of 22C (72F). Limited sunshine today should keep the temperature down to 25C (77F). We managed a high of 28C (83F) Monday, despite the clouds and early showers. Montreal has already recorded five 30C-or-warmer days at Trudeau Airport. We did not record a 30C high in Montreal until July 7 during the summer of 2015. Today's cold front will usher in a slightly cooler air mass for Wednesday, with expected high temperatures in the low 20's accompanied by a shower or two. High pressure will clear skies along with a warming trend for Thursday and Canada Day. Look for wall-to-wall sunshine to start the holiday weekend, with highs near 27C (81F). At this time, a few showers are forecast on Saturday, but I am not overly confident with that forecast.

Conditions remain very dry across the region, with slight-to-moderate drought being reported from southern Ontario into Quebec and New England. According to the United States Drought Monitor, many Northeast and southern St. Lawrence Valley locations are reporting only 25 to 50 percent of normal rainfall.

EF2 Tornado
Environment Canada has confirmed the second tornado of the year for Quebec. It occurred on a very warm and humid June 20th in Lac Verne. The EF2 tornado, with an estimated 190km/h winds, destroyed a cottage and knocked down a strand of trees. Two people were seriously injured in the storm. Quebec records an average of 6 tornadoes a year. (The Enhance Fujita Scale rates tornadoes from EF0, the weakest, to EF5, the strongest).