Heat warning in effect for Montreal and the entire region

The high of 32.1C (90F) at Trudeau Airport Friday, missed the 1970 record by one tenth of a degree. We have a shot at beating both record highs this weekend. Humidex values reached 40C during the late afternoon hours, and will likely do so again on Saturday. A heat warning is in effect for the St. Lawrence Valley.

Heat Warning in effect for the St. Lawrence Valley, southern Quebec, eastern Ontario and the Champlain Valley of New York and Vermont. Stay hydrated, wear light clothing and avoid strenuous outdoor activities. Seek air conditioning if possible.

Hot and humid air has settled over southern Quebec and Ontario for the weekend, fueled by strong high pressure located off the Atlantic coast. This Bermuda high is pumping tropical air northward into our region. Adding to the moist, steamy air mass is the northward track of tropical storm Henri.

Saturday will be hazy and hot in Montreal with a high of 33C (91F) forecast and humidex/heat index values into the low 40s. Sunday will be similar, with a high of 32C (90F), but with some high clouds streaming northward form Henri, as the storm makes landfall on Long Island, New York and moves into southern New England. There is a risk of perhaps a few showers along the US border late Sunday as well as a wind shift to the northeast in the afternoon. At this time little other impacts are expected in Quebec, with Henri forecast to move northeast after landfall, well south of Montreal.

In terms of high temperatures for Montreal this weekend, we have a chance at exceeding the long-standing record highs for both Saturday and Sunday. The record high for both days was established in 1955, 32.8C Saturday and 30.6C Sunday.

Tropical Storm Henri

Henri was located 315km southeast of Cape Hatteras, North Carolina at 5am Saturday morning, with 110km/h winds. Henri is expected to strengthen into a hurricane on Saturday, while maintaining a northward track. Widespread watches and warnings have been posted for the northeastern US and southern New England including metropolitan New York City. Rainfall of up to 250mm, along with a storm surge of 3 to 5 feet is expected. The storm is expected to make landfall on central Long Island during Sunday afternoon. The center will then move inland across far western Massachusetts before moving northeast into Maine. The path of Henri will have to be watched closely to see what impacts if any we can expect locally. It appeared earlier in the week, that Henri was moving out to sea. Since then, each successive forecast model run has moved the storm closer and closer to an expected US landfall close to New York City.