Depending on how much rain falls on the London region over the next day and a half, the Upper Thames River Conservation Authority (UTRCA) is warning flooding could become an issue.
Environment Canada has much of southwestern Ontario including London and Middlesex County under a rainfall warning. According to the national weather agency, as much as 60 mm of rain could fall on the area by early Thursday morning. That rainfall total goes up to a possible 125 mm should multiple thunderstorms materialize.
If that happens, area residents should brace for flooding on roads and near waterways.
"Rainfall over the past two weeks has made the Upper Thames River watershed more susceptible to runoff, but if we get the lower forecasted rainfall amounts, we do not expect significant river flooding,” Mark Shifflett, UTRCA senior water resources engineer, said in a statement. “However, if the higher rain amounts fall over a wide area, we may see more serious river flooding.”
The conservation authority will use its control reservoirs at Fanshawe, Wildwood, and Pittock conservation areas to try to reduce any downstream flooding. Currently, the three reservoirs are at seasonal levels.
People across the region are asked to use extreme caution around waterways for the time being as they may become fast-moving and higher than normal. Parents should keep children and pets away from all creeks, rivers and water bodies, the conservation authority said.
The expected wet weather is the result of a cold front and moisture laden low pressure system moving in from the American mid-west. The heavy downpours could cause flash flooding and water pooling on roads.