Area conservation authorities are issuing water advisories in advance of heavy rainfall and possible thunderstorms anticipated on Wednesday.
The Ausable Bayfield Conservation Authority (ABCA) issued a flood watch Tuesday afternoon, and the St. Clair Region Conservation Authority (SCRCA) put a flood outlook in place.
The ABCA said a Colorado Low will move into southern Ontario on Wednesday, pulling in a steady inflow of moisture.
It's expecting between 40 and 60 milimetres of rain to fall, lasting into early Thursday morning.
The ABCA said the track of the heaviest rains is unknown. However, current forecasts predict higher rainfall in the north half of the watershed.
The organization said we could see the highest water levels in several years, and road closures may be necessary.
Flood levels on the larger rivers are expected to peak on Thursday, smaller rivers and creeks are forecasted to see peak levels late Wednesday and into early Thursday.
In the meantime, the SCRCA said upwards of 75 mm of rain is forecast Wednesday, and up to 100 mm of accumulated rainfall could be seen over the next five days.
It's expecting rainfall rates of between 2 mm and 7 mm per hour before subsiding Thursday morning.
A brief reprieve is forecast for Thursday, followed by 5 mm of rain on Friday and a further 5 mm to 10 mm for Saturday.
Residents are reminded to use extreme caution near all watercourses.
Slippery and unstable streambanks, and extremely cold and fast-flowing water will combine to create hazardous conditions.
We're reminded not to try and drive on flooded roadways.