Another wet summer weekend for Montreal

The weather has been highly changeable in Montreal this June, with frequent showers and thunderstorms, and impressive quantities of rainfall, including a record-setting 53.4mm falling in less than 24 hours on June 23. Another round of showers and thunderstorms is expected this weekend. (Valley Weather Photo)

Special Weather Statement issued by Environment Canada for southern Quebec, for heavy rainfall this weekend.

Our wet June continues, with another showery, humid weekend in the forecast for southern Quebec and eastern Ontario. Sadly it will be the third in a row. A fast moving west to east zonal flow has been responsible for the rapidly changing weather this month. We remain on the northern periphery of a large heat dome located across the southern and eastern United States that has been responsible for our brief but significant hot and humid stretches this month.

Montreal has had a real mixed bag of weather, with 7 days above 30C (86F) and over 122mm of rain to date. The normal is only 83.6mm. We will add to that rain total this Canada Day weekend, as a potent weather system moves across the region, bring periods of heavy showers and embedded thunderstorms, especially late Saturday into Sunday. Precipitation amounts are expected in the 20-40mm range, but may exceed 50mm in the most persistent thunderstorms. While this will bring our rainfall up to impressive levels for June, it is far from the record of  219mm set way back in 1922.

What the rain and muggy weather has accomplished other than disrupting outdoor activities, is it has lowered the fire risk across Quebec. To date according to SOPFEU, we have had 197 wildfires, well-below the 10 year average of 289.

As far as temperatures go, we had a very chilly morning Friday behind Thursday's windy cold front. The low here on Ile Perrot was only 8C (47F). The temperature will recover under the warm June sun to around 24C (75F) Friday. Expect muggy daytime highs around 25C (77F) bot Saturday and Sunday. Any sunshine both days will help increase temperatures as well as instability and lead to more active thunderstorms. The weather should improve for Canada Day Monday in Montreal, with a high of 25C (77F). Warm and humid weather will return by the middle of next week.

Widespread showers and thunderstorms Sunday for Montreal

Heavy rain and thunderstorms are expected on Sunday in Montreal. A heavy rainfall warning has been issued for southern Quebec and eastern Ontario for 50-75mm. This amount of rainfall is capable of flash flooding as well as ponding of water on area highways. Further south strong thunderstorms and even isolated tornadoes are possible in upstate New York and Vermont.

Heavy Rain Warning for Montreal and Ottawa.

A heavy rain warning was has been issued by Environment Canada for metro Montreal, southwestern Quebec as well as eastern Ontario. A significant severe weather outbreak is possible further south across portions of New York and New England on Sunday.

For the St. Lawrence Valley, a warm and muggy airmass remains across the region despite the passage of a cold front late Thursday. While temperatures are much cooler, atmospheric conditions remain humid and unsettled. The aforementioned front will move back north as a warm front Saturday evening, stalling along the international border and become the focus for heavy rain and thunderstorms overnight Saturday and most of the day Sunday.

At this time, 50-75mm (2-3 inches) of rainfall is possible within the most persistent shower activity. The heavy rainfall may produce local flash flooding as well as ponding of water on area roads. Temperatures will remain warm and muggy through the period, dropping to near 19C (66F) tonight and rising to 25C (77F) Sunday.

While we are not expecting severe weather in Montreal, some of the storms will have gusty winds and lightning. Outside of the storms, winds will be gusty, out of the southwest 40-60km/h.

If you have travel plans into upstate New York or Vermont on Sunday, be weather aware and keep an eye to the sky. They will be in the warm sector, with an elevated risk of afternoon thunderstorms. Some of the storms will be severe, with gusty winds, hail, heavy rain and even the possibility of tornadoes.

Significant heatwave expected for Montreal

A cold front produced strong thunderstorms Thursday afternoon and evening across parts of central and eastern Ontario as well as far western Quebec. Some damage was reported, including the downed tree shown above in Augusta Township. There were even several tornado watches posted north and wets of Gatineau. Montreal only received a few evening showers from the same front. (OPP East Photo)

Environment Canada has issued a special weather statement for high heat and humidity next week. This will likely be upgraded to heat advisories/warnings as the event draws closer.

A cold front on Thursday produced some widely scattered thunderstorms across southern and western Quebec. Most of the severe weather remained across far western Quebec and Ontario. There were even tornado watches and warnings issued north and west of Ottawa and Gatineau.

After a rather chilly and at times showery week, we are looking at a spectacular Father's Day weekend. High pressure will dominate, with bright sunshine and seasonable temperatures across southern Quebec. Winds will be light and the humidity will remain low. High temperatures will be in the low to middle 20s, with lows in the teens. Enjoy it.

Starting Monday, we have a significant 3-4 day heatwave forecast for most of eastern North America. Record highs will be in jeopardy across a wide region including southern Ontario and Quebec as well as New England. A Bermuda high will pump increasingly hot and humid tropical air northward. As the the heat dome expands, high temperatures will climb into the middle 30s in Montreal, along with elevated humidity and dew points, producing humidex values over 40C.

Record highs in Montreal will be challenged from Monday through Wednesday at the very least. Overnight lows will remain very warm and uncomfortable, staying in the 20s. As far as the all-time record high is concerned, time will tell. The temperature to beat from Trudeau Airport in Dorval is 37.6C (99.7F), set on August 1, 1975.

If you need to have your air conditioning installed or serviced, now is the time to do it. Montreal has already recorded one heatwave this year with the summer season just beginning.

Severe thunderstorm watch - wet Grand Prix weekend

Rain and the Formula F-1 Grand Prix du Canada in Montreal are sadly no strangers to each other. Qualifying ran in the rain last year, and will most likely again this year. Showers are forecast from Friday through Sunday for the Montreal region. 

A severe thunderstorm watch has been issued for Montreal on Thursday, after our first heatwave of the season produced three consecutive record highs at Trudeau Airport. The watch covers a large portion of southwestern Quebec and eastern Ontario. Storms are expected to develop along a cold front moving east across Ontario.

The main threat for theses storms will be heavy rainfall, up to 50mm locally. Additionally strong winds will be possible as well. The heavy rain will result in some flash flooding along with ponding of water on area roads.

The front unfortunately will introduce a rather lengthy stretch of cooler and damp weather into the weekend, with frequent showers expected. This will put a wee bit of a damper on the weekend activities associated with the Formula F-1 Grand Prix du Canada, scheduled for Sunday at 2pm at Circuit Gilles Villeneuve.

The first heatwave of the season this past week was quite impressive, breaking three record highs for Monday through Wednesday at Trudeau Airport. On Monday the high was 30.8C (88F), breaking the 1967 record of 30.6C (87F). Tuesday's high of 31.4C (88F) surpassed the 1963 high of 30.6C (87F). Finally on Wednesday, Montreal reached 31.7C (89F), beating the 1967 record of 30.6C (87F).

Warm start to meteorological summer in Montreal

The photo above was provided by the home owner to the survey team from the Northern Tornadoes Project. The team determined that last Monday's tornado was an EF1, producing winds of up to 155km/h. The tornado was on the ground for 14.3KM west of Rigaud, producing some significant damage along the way. It was only the second tornado of the season to date in Canada, with severe weather season really just beginning across the country. (NTP Photo)

Southern Québec is in the middle of a warm, dry stretch of weather for the start of meteorological summer which occurred June 1st. Temperatures have risen to well-above normal values, reaching 27.2C (80.7F) on Saturday, and 28.3C (82.9F) Sunday. Conditions will remain the same through at least Wednesday, with highs approaching 30C (86F) in Montreal, and overnight lows remaining in the upper teens.

Conditions will be rather dry to start the week, with humidity levels slowly rising through the middle portion of the week. High pressure will dominate, slowly moving east across southern Quebec and into northern Maine. By Thursday, an upper level low over the Great Lakes will be begin to slide across southern Quebec and take up residence into next weekend. Sadly this means a prolonged period of shower, thunderstorms and cooler weather into Grand Prix weekend here in Montreal.

Until then, we are looking at our potential first heatwave of 2024, that is three consecutive days with high temperatures at 30C (86F) or higher. With the hot and dry weather comes an increase in fire concerns. SOPFEU has indicated a very high fire danger across the southern portion of the province over the coming days. Any type of outdoor burning should be avoided until we receive additional rainfall later this week. As of Monday morning, SOPFEU has cancelled any industrial and commercial burning permits in the province through June 8.

RIGAUD TORNADO

The Northern Tornadoes Project from Western University in London, Ontario, finished their investigation into the first Quebec and second Canadian tornado of the young 2024 season. Last Monday afternoon's storm touched down at around 5.30PM, south of Pointe-Fortune travelling northeast. The storm moved 14 kilometres on the ground along the Quebec/Ontario border, just west of Rigaud. The tornado was rated as n EF1 on the Enhanced Fujita Scale, producing winds of 155km/h. It resulted in downed trees and power lines, significant damage to several homes, a farm and vehicles.