Tropical storm Debby to impact southern Quebec

Flash flooding in Charleston, South Carolina, after tropical storm Debby produced over 300mm of rain on Tuesday. Debby is expected to bring heavy rain to Montreal by Friday. (Photo: Henry Taylor) 

Special Weather Statement issued for Montreal, for heavy rainfall in association with the remains of tropical storm Debby, expected by Friday.

Tropical storm Debby, located in the Atlantic Ocean, 85km southeast of Charleston, South Carolina at 11am Wednesday morning, is slowly meandering northeast at 7km/h. The storm has brought historic flooding to portions of northern Florida, southeast Georgia and South Carolina since late Sunday. Hundreds of thousands of homes and businesses were left without power after the storm made landfall in the Big Bend region of Florida early Monday morning.

Since Monday, Debby has been slowly moving across Georgia and is now back over the open waters of the Atlantic. Debby has strengthened a little Wednesday morning, with winds of 95km/h (60 MPH). Debby should make landfall in South Carolina later this evening before moving off towards the northeast into the middle Atlantic states.

The latest forecast track for tropical storm Debby, has the system passing southeast of Montreal early Saturday morning. Heavy rain, up to 100mm is possible across our region, but that may change as the event draws closer. Flash flooding is possible across a wide area from the US southeast into eastern Quebec. (NHC)

Significant rainfall, in some cases over 500mm (20 inches) is occurring across portions of the US southeast. This has resulted in significant fresh water flooding. The flood threat will spread all along the path of Debby into the Northeast, New England and eventually southern Quebec. Regions along the storm track can expect 50-200mm (2-8 icnhes) locally.

Debby is forecast to merge with a frontal boundary by Friday as the depression moves across northern New England to lie near Lake Champlain by early Saturday morning. The strom will then move into southern Quebec.

At this time we expect a swath of heavy rain across southern Quebec and eastern Ontario, including the metro Montreal region. It is too early to determine exact amounts, but the region could possibly see 50-100mm (2-4 inches) of rain between Friday morning and Saturday evening. Additional showers are expected into Sunday. The final track of Debby will determine where the heaviest rain occurs.

Many parts of New England and extreme southern Quebec have already experienced a very wet June and July. There has been significant flash flooding in parts of Vermont this summer, so any additional rain will only add to the saturated ground. 

Weather watches and warnings may be required as the event draws closer. Until then enjoy the spectacular weather Wednesday and Thursday in Montreal, with sunshine and high temperatures in the upper 20s.