Brace yourself for three days of rain.

Environment Canada issued a special weather statement Thursday about a significant system that could bring between 40 and 70 millimetres of rain to parts of southern Ontario including Toronto, Hamilton, Peel and York regions and Peterborough.

The wet weather is expected to start this afternoon and continue through to Saturday, when it is likely to taper off.

In the wake of recent bouts of rain earlier this week, the weather agency is warning that flooding is possible in low-lying areas.

“With the ground already saturated, there is the potential for local flooding,” the advisory reads.

Toronto and Region Conservation said in a statement that while fluctuation of lake levels is normal, waves caused by high winds can pose a danger.

“As lake levels are expected to continue to rise, TRCA is asking all residents and children to exercise caution along lakefront areas while high water levels and wind persist,” the TRCA said. “Elevated lake levels combined with wave activity can make these areas potentially dangerous. Use extra caution when around any water bodies.”

The City of Toronto has set up an emergency evacuation plan for residents living on Toronto Island in case Lake Ontario reaches unsafe water levels.

The rain will be accompanied by a high of 9 C today and 10 C Friday. On Sunday, with a low of 1 C expected, a mix of rain showers or flurries is possible.

It’s not until Monday that sunshine returns, but it won’t last long. There’s a 30 per cent chance of showers on Tuesday, with a high of 13 C.