The Ausable Bayfield Conservation Authority is warning the area could see the highest stream flows in a decade as a low-pressure system moves in from the United States and dumps rain on the area.
The conservation authority updated it's flood message to a flood watch this morning, saying if we get as much rain as feared, numerous road closures are likely especially on roads that are prone to flooding.
In a release, officials said the heavy rain will begin Friday night and continue through Saturday, bringing totals of 60-75 millimetres across the watershed.
The forecasts are still not certain of the exact track of the storm and right now the northern portion of the watershed is on the boundary of freezing rain potential. Prolonged freezing rain would limit how much flooding occurs. With little or no ice cover on area watercourses, ice jams are not going to be a factor.
Everyone is urged to stay away from watercourses. The cold water, slippery and unstable banks are creating a serious hazard.
Municipal staff are being told to monitor local drainage problem areas including snow and ice-covered catch basins.
Meanwhile, the Maitland Valley Conservation Authority is expecting minor flooding in low-lying floodplain areas.
The conservation authority said the Maitland and Nine Mile River watersheds are expected to get 50 millimetres of rain through Saturday and another 25 millimetres in the form of freezing rain.
The temperature is expected to drop below freezing early Saturday afternoon and that will reduce the risk of flooding. If that temperature drop does not happen and we get more than 75 millimetres of rain, the conservation authority said the area could see more significant flood levels, similar to what was experienced in late December 2008.
Officials will be keeping an eye on the storm and updating their flood message if needed.