Torrential downpours early Wednesday morning have prompted Environment Canada to issue a rainfall warning.
The weather agency says rainfall amounts of 50 to 85 mm have been reported across parts of Eastern Ontario including Ottawa this morning.
Total rainfall amounts will reach 100 mm in a few localities by noon today.
As of 8 a.m., 43.1 mm of rain had fallen at the Ottawa Airport. That sets a record for the wettest July 25 in Ottawa history.
The previous record for July 25 was 41.1 mm set in 1969.
There have been reports on social media of localized flooding on Ottawa streets.
With files from CTV Morning Live's Josh Pringle.