Major flood event unfolding over the next 24-48 hours across portions of our region

Torrential rain and thunderstorms are likely to produce major flooding over the next 48 hours across southeastern Quebec, New York and New England.

Serious language is being used by several forecasters regarding heavy rain and the potential for dangerous flooding across a large portion of southeastern Quebec and northern New York and New England over the next 48 hours. If you live in a flood prone area pay close attention to weather conditions and additional warnings.

Heavy rainfall warnings are now in effect for a large portion of southern Quebec, just east and southeast of the metro Montreal region, including parts of the South Shore, the Townships and Quebec City. At this time, 25 to 50mm (1-2 inches) of rain is forecast for Montreal, with up to 100mm (4 inches) or more southeast of the city and across Vermont and northern New York. Flash flood watches and warnings are numerous across the northeastern US and New England. Isolated amounts may approach 200mm (8 inches).

Strong wording from the National Weather Service in Burlington, Vermont, comparing this event to that of Hurricane Irene back in 2011. Major flooding is anticipated, extending into southeastern Quebec. (NOAA/NWS)

Deep tropical moisture is moving northward into very unstable, humid air. The circulation along a warm front will draw in copious amounts of moisture from the Atlantic Ocean into our region. Rounds of heavy rain and thunderstorms are forecast to develop tonight and persist into Tuesday morning across the entire region. The rain will be torrential at times, with some locations along the US border and in the Champlain Valley receiving up to 50mm in less than an hour. The ground is already saturated in those locations, so any additional rainfall will simply runoff into local waterways producing major flooding.

Flash flooding has already been reported in southern New York and across northeast Pennsylvania on Sunday.

The National Weather Service in Burlington, Vermont is comparing the rain potential to that of Hurricane Irene back in 2011 that devastated parts of Vermont. They are calling this potentially a 100 year flood event for Vermont and portions of New York. The same wording is now be extended northward into parts of southern Quebec, especially the Eastern Townships.