In a news release, officials say a band of steady rainfall overnight brought around 15 to 45 millimetres of rain with heavier amount in the eastern and northern portions of the watershed.
They say the combination of rain and warm temperatures has ripened the snowpack and can no longer hold any more water.
Residents are being reminded to use caution near all watercourses as ice on rivers and ponds will become very unstable.
They add slippery streambanks and extremely cold and fast-flowing water will combine to create hazardous conditions.
The water safety statement will remain in effect throughout the Family Day weekend.