Some areas is expected to get up to 60 mm of rain between Thursday and Friday.
Environment Canada has expanded its flood risk warning to include Ottawa and all of Eastern Ontario as a powerful Texas low moves north.
The agency says rain will begin Thursday morning and continue through Friday, with totals between 25 and 50 millimetres - and up to 60 in some areas.
Senior Climatologist David Phillips with Environment Canada says the storm is the latest in a wetter-than-usual October following an unusually dry spring and summer.
Phillips highlighted where the storm will hit.
He explained what makes this storm different from your everyday system.
Phillips said there is expected to be anywhere from 20 to 50 millimetres of rain, with some areas receiving over 60.
Looking ahead, Phillips shared his outlook for what conditions are expected to be like on Halloween evening.
Environment Canada advises residents to monitor local forecasts and prepare for possible flooding in low-lying areas.
Motorists are urged to drive with caution as heavy rain may lead to pooling water and reduced visibility.
Story by Evan Gibb
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