Seasonable weather week ahead - wildfire smoke remains west of Montreal

The annual Notre-Dame-de-L'Ile Perrot car show took place this past Sunday at Pointe-du-Moulin. The show was well-attended, with spectacular near-perfect summer weather prevailing. This was in stark contrast to the washout on Saturday, with showers and thunderstorms all day in Montreal. Rainfall amounts however were lighter than forecast, with only 5-10mm in the Montreal region.(Valley Weather)

The fire situation across western Quebec and northern Ontario remains critical, with hundreds of fires burning. In Quebec, there are 180 active fires according to SOPFEU. Firefighters are already assisting in Quebec from New Brunswick, Prince Edward Island, Alberta and British Columbia. An additional 18 firefighters will arrive from the Untied States, with 43 from France.

With the wind this week predominately from the north and west, smoke should drift across the central Great Lakes and into the upper Midwest. Smoke from Alaskan wildfires is drifting across northern Canada adding to the poor air quality across the west. Montreal will remain on the eastern edge of the smoke fro now.

The weather will turn cooler with some rain across the fire region as low pressure moves well north of our region across Ontario and Quebec. Here in the southern part of the province, we can expect a seasonable week, with highs in the middle 20s and lows in the teens.

Some shower and thunderstorm activity is possible in Tuesday into Wednesday morning. The threat for severe weather is low this week. Otherwise expect sunshine through Saturday.

The hot and humid weather will remain in place across the central portion of the United States this week giving southwestern Quebec and southern Ontario a break. 

Along the Gulf coast, a weak tropical storm is expected this week. Early Monday morning, tropical depression 2 was located 180 kilometres south of Panama City, Florida, with 55km/h winds. The storm is forecast to become tropical storm Bertha this week, while slowly moving northwest towards the Louisiana coast. The main threat with this storm will be heavy rain and flooding from the Florida panhandle to Texas.

Wet Saturday for Montreal - smoke moves south

Widespread air quality advisories stretch across central and southern Ontario and most of the northern and eastern United States. Dense smoke from wildfires burning across northwest Ontario and northern Minnesota have resulted in some of the poorest air quality in the world over the last few days. Little relief is in site as winds oscillate the smokey air back and forth across the international border. (NYSDOT)

The big story this week is the widespread forest and wildfires burning across parched regions of northwest Ontario into western and central Quebec. Over 180 fires are burning in Ontario, with an additional 19 active fires in Quebec. The total in Quebec for the season is now at 326, of which 72 were caused by lightning and unfortunately 241 by human activity. The Ontario fires are beginning to threaten communities, with evacuations being considered for residents of at least 15 municipalities. Some rain is forecast for the weekend, but also the risk of lightning which may spark additional fires.

The skyline of Toronto on Wednesday, covered in thick smoke from wildfires burning in northern Ontario. The city is fourth on the list of poorest air quality among major cities worldwide on Friday morning.

The Ontario fires have sent plumes of thick smoke southeast across the Great Lakes and into major cities like Toronto, Detroit and Chicago. Air quality has been greatly diminished across Ontario as well as the northern and eastern United States. Residents were being urged to remain indoors Friday, as trips to the emergency room for respiratory issues have spiked, especially in Ontario, Michigan and New York.

Here in Montreal, we have been spared the smoke as most has drifted south and west of the city. We may see some smoke return on Sunday as winds veer to the west and northwest behind a strong cold front.

Our weather will be sunny and seasonable on Friday, a near-perfect summer day, with a high temperatures near 25C (77F). Clouds will increase after midnight as a strong area of low pressure moves down the St. Lawrence Valley. Showers and thunderstorms are forecast most of Saturday, with 20-25mm of rain possible. A cold front late in the day Saturday may produce some vigorous thunderstorms, but the severe weather threat for Montreal is low at this time. Daytime highs will be near 25C (77F), with overnight lows behind the rain dropping to a comfortable 15C (59F)

High pressure should build back in Sunday resulting in a very pleasant, sunny day. The high will be near 24C (76F). Wildfire smoke may return to southern Quebec on both Sunday and Monday.

Forest fire smoke diminishes severe weather in Montreal

Dense smoke from northern Ontario wildfires turns day into night in Thunder Bay on Tuesday afternoon. Thunder Bay was one of the warmest locations in the country on Monday, surpassing 40C (104F). Fires have exploded across that region, sending smoke drifting across southern Ontario and into southwestern Quebec. The smoke has resulted in hazy sunshine and very poor air quality. (Sarah Law/CBC)

Plumes of smoke are drifting across Ontario and southern Quebec on Wednesday from massive forest and wildfires burning across northwest Ontario. At least a dozen new fires have erupted this week, fueled by intense heat, over 40C in some locations, and widespread lighting strikes. To date over 450 fires have been reported in Ontario, with 302 in Quebec. Several are burning out of control in both provinces, resulting in very poor air quality across eastern Canada and the United States.

In fact, early Wednesday morning, Toronto had the poorest air quality of any major city in the world, with a AQI rating of 192, in the unhealthy range. Montreal sits at 73 by comparison, in the moderate range. Air quality advisories are widespread across Ontario. The smoke is obscuring the sun and resulting in a very smokey smell in the air. 

Gusty west winds up to 50km/h are helping to spread the smoke across southwestern Quebec. Conditions will remain poor into Thursday before the arrival of a cold front pushes the smoke south.

The smoke on Tuesday managed to cap the atmosphere here in southern Quebec, resulting in a greatly diminished thunderstorm threat. Capping the atmosphere occurs when warmer air aloft and cooler air at the surface, results in supressing vertical air movement and thus thunderstorm development. Temperatures across our region were around 30C (86F) as opposed to the middle 30s (90s) that were forecast.

Despite the cap, storms still developed, some severe, but the threat was greatly reduced during the daylight hours. Stronger storms did occur after dark, but mainly west of Montreal and south into New York. Those storms produced large hail in parts of the Ottawa Valley as well as the Seaway Valley of upstate New York into the Adirondacks.

The storms did result in over 10,000 lightning strikes over a 24 hour period from Ontario across southern Quebec and into the northeastern US. Earlier in the day Tuesday, a swath of strong storms affected the region between Montréal and Quebec City, southeast across the Eastern Townships prompting a tornado watch by Environment Canada. As I write, no tornadoes were reported.

The weather will remain hazy and warm in Montreal through Thursday.

Elevated risk of severe thunderstorms with the chance of a tornado

Strong and dangerous thunderstorms are possible Tuesday afternoon in the Montreal region, with the risk of isolated tornadoes across southern Quebec. Stay weather alert today and listen for subsequent warnings which will be issued for specific regions as the threat develops. (Valley Weather)

Severe Thunderstorm Watch in effect for metro Montreal

The risk for dangerous weather is elevated today for southern Quebec trhough Tuesday evening. Have a method to receive updated weather warnings and a plan to seek safe shelter immediately if threatening weather approaches.

All the ingredients are present today for a significant severe weather outbreak across eastern Ontario and southwestern Quebec. The parameters are as high as many forecasters and amateurs alike have seen across our region. Hot and humid air is in place, with the trigger being a cold front slipping from north to south across our region late this afternoon. We have strong winds high in the atmosphere and deep tropical moisture available at the surface. 

I still think the greatest threat for a tornado would be east of Montreal, but that does not make these storms any less dangerous for Montreal. Stay alert.

The latest severe weather update from Environment and Climate Change Canada (ECCC), places our region under an elevated risk for severe thunderstorms Tuesday afternoon. The primary threat will be strong winds and hail, but flash flooding and isolated tornadoes are possible as well.

Strong thunderstorms along with isolated supercells are expected to develop late this afternoon north of the city, and move across the Montreal region between 4pm and 6pm, with the severe threat remaining until midnight.

The storms will be capable of powerful straight line winds in excess of 100km/h, large hail, torrential rain, flash flooding and frequent lightning. Some of the storms will be capable of rotation and isolated tornadoes are not out of the question. If a tornado does occur it could be particularly strong with this setup, and travel great distances with the parent storm.

Temperatures will be very warm and muggy, with highs in the middle 30s in Montreal. The one thing I am seeing this morning is the presence of cloud cover and forest fire smoke aloft in the atmosphere. We will see what type of an impact this has on the temperatures and eventual storm development as the day progresses.

The threat for severe weather should end by midnight in Montreal.

Be prepared for severe weather today. Theses storms are capable of wind damage, power outages and challenging driving conditions in torrential rain. The threat will extend from the Ottawa Valley to Quebec City and south into northern new York and New England as well as western New Brunswick to the east.

Surge of heat and humidity for Montreal

A perfect retreat during the warm summer weekend, along the St. Lawrence River in LaSalle overlooking the Lachine Rapids. Just a few fair weather clouds dotted the sky the entire weekend, with comfortable daytime highs near 28C (83F), and lows near 16C (60F), along with low humidity. It was an ideal weekend for anything outdoors in Montreal. (Valley Weather Photo)

Widespread heat and humidity warnings are in effect from North Dakota to eastern Ontario and New England and will likely be issued for parts of Quebec for Tuesday.

Some of the warmest temperatures so far this summer are set to surge into southern Quebec and Ontario this week. How warm? Dozens of record highs were established in Manitoba over the weekend, as highs topped out in the middle 30s. Even overnight temperatures remained in the upper 20s. Humidex reading were as high as 45C. That heat is set to arrive Monday and spread east.

For Montreal, Monday will feature hazy sunshine, with a high close to 30C (86F). A few clouds and perhaps an isolated shower or thunderstorm are possible late in the day, but the risk is low. Warm southwest winds will develop Monday and increase on Tuesday, gusting 20-50km/h at times.

That breeze will usher in very high humidity, along with temperatures as warm as 35C (85F) across some southern Québec locations on Tuesday. Morning lows on Tuesday and Wednesday will be very warm, in the middle to upper 20s for most locations. Some smoke from northern Quebec forest fires is possible, especially in the Ottawa Valley.

On Sunday, parts of northwest Ontario, including Sioux Lookout, flirted with the 100F (37.8C) mark. There is a chance that some locations from Windsor, Ontario east towards western New York may reach 100F Tuesday. I think Montreal will remain below our all-time record high of 37.6C (99.6F) set on August 1, 1975. We should easily challenge the daily record high of 33.3 (91.9F) set in 1921.

Along with the heat will be high humidity levels, pushing humidex values into the middle 40s for most locations. A cold front late Tuesday is expected to produce some very strong if not severe thunderstorms along and south of the St. Lawrence Valley. There is an isolated risk of some supercell storms, that could produce strong winds, hail, heavy rain and even an isolated tornado. The threat would be between 6pm and midnight for southern Quebec.

Warm but less-humid weather will continue for the rest of the week, with seasonably warm highs in the upper 20s.

The fire situation remains serious across central, western and northern Quebec. Any type of outdoor fire remains prohibited across all of Quebec north of the St. Lawrence River, and is highly discouraged in other regions. To date, 295 fires have occurred in Quebec this year, consuming more than 102,000 hectares of forest. Of those fires, 227 were caused by human activity, with 56 blamed on lightning according to SOPFEU.

Beneficial rain for Montreal - fire danger remains high in northern Quebec

One of 200 wildfires burning across Quebec, this one located near Chisasibi, west La Grande and Radisson. (SOPFEU)

A slow moving front brought some much needed moisture to the entire southern Quebec region on Thursday. It was a slow, steady rain the produced 20-25mm across the region. While June was wet in Montreal, the rain was very localized in nature as we all know. This rain was widespread and at a manageable rate.

The moisture will certainly reduce the wildfire risk from the Saint Lawrence River south, but it remains high across northern and central portions of Quebec. There are over 200 wildfires currently burning across the province, with at least two out of control. As a result, an outdoor burn ban is in effect across most of the province north of the St. Lawrence River. This means if you have camping plans in the Laurentians, you will not be allowed campfires.

The region of far northern and western Quebec has had a very dry and warm spring and summer to date. A large area of the northwest Quebec recorded between 50 and 75 percent of normal precipitation for June.

The fires have resulted in the evacuation of several communities. SOPFEU, the provincial forest fire agency has over 900 firefighters and personnel battling the fires. This includes over 100 firefighters from British Columbia, Alberta and Prince Edward Island. Over 20 aircraft and 50 helicopters are assisting in the battle.

Warm and dry weather is expected to return to the province over the next week, with high temperatures exceeding 30C (86F) once again, along with very little rainfall. 

Most of the fires this year have been started by human activity, at last count 225. This displays firsthand the negative impact we can have on the forest fire season. This is why the fire ban is so important and backed by fines of up to $5000. According to SOPFEU, an additional 52 fires have been started by lightning strikes.

The current wildfire situation in Quebec, with an outdoor burn ban in effect for all of the province north of the St. Lawrence River. (SOPFEU)

Much calmer weather week ahead for southern Quebec

The weekend was spectacular across southern Québec, with sunny, warm weather. Conditions were less humid and thankfully no thunderstorms. (Valley Weather)

We are looking at the calm after the thunderstorms for most of southern Quebec. Last week was filled with multiple rounds of thunderstorms, wind damage, power outages, flooding and searing heat. By stark contrast, the weekend was calm and spectacular, finally dry for many, warm but less humid. 

High pressure has settled into eastern Ontario and southern Quebec to start the work week. This will keep low pressure well to our south across the Ohio Valley, eastward into the middle Atlantic states. This region will be the focus of heavy rainfall Monday along with thunderstorms. Flash flooding has occurred or is expected from Ohio east towards New York City. Flood watches are in effect from Virginia to southern New England.

Meanwhile here in Montreal and across southern Quebec and eastern Ontario, we can expect nothing but sunshine, with highs between 28C and 30C (83-86F). Overnight lows will remain pleasant, dropping into the middle teens. 

The next chance of shower activity will not be until Thursday, with the arrival of a cold front. Showers and scattered thunderstorms are possible. Skies clear out for Friday, with another fair weekend expected at this time.

Rainfall has been highly variable across our region this July. Parts of Ontario and Quebec have measured well over 100mm of rain to date, while Trudeau Airport sits at 24.5mm. I have recorded a paltry 2.6mm at my weather station on Ile Perrot. Municipalities on the West Island are still cleaning up from the major flood on June 22, while nearly 1900 homes were flooded in the Ottawa area on July 1st.