SD&G – Environment Canada is expecting up to 35 millimeters (1.38 inches) of rain Wednesday across the region.
The weather agency updated its ongoing special weather statement around 9:45 p.m. Tuesday, saying the rain would begin overnight or early Wednesday morning.
Rainfall amounts of 20-35 millimeters (0.78-1.38 inches) are expected by the time the weather system is done Thursday morning.
The rain is from a Texas Low tracking across southern Ontario.
All that rain is putting pressure on the Great Lakes system.
Less water is being let through the Moses-Saunders Dam in Cornwall to prevent flooding in the Montreal area. That’s led to rising water in areas of the St. Lawrence River west of Cornwall.
The International Lake Ontario-St. Lawrence River Board says the river system is already in a “major flood event” – higher in some areas than 2017 levels – and the water will continue to rise this week.
The board says outflows from Lake Ontario have been increased “several times since Sunday afternoon and increases will continue as quickly as possible over coming days.”