A rainfall warning is in effect for much of eastern Ontario and western Quebec, at a time when flood waters are expected to peak at never before seen levels.

Thursday's special weather statement advising residents of significant rainfall totals Friday through Saturday has been upgraded. While the expected rainfall totals have not change, Environment Canada says the soil will not be able to absorb as much of the coming water.

For Ottawa, Gatineau, and areas to the immediate east and south, the statement says 20 to 35 mm of rain is possible. Rainfall totals in the Ottawa Valley could be between 25 and 40 mm, the statement says, with the possibility of 50 mm of rain in some localized areas.

Environment Canada says this rainfall is associated with a Texas Low that will move across southern Ontario Friday.