Flood watches are in effect until 4pm Tuesday for the valley, Coast Range mountains and Oregon coast as heavy rain and melting snow cause rivers and streams to rise. The rivers/streams with greatest potential to flood are rivers draining the east and west slopes of the Coast Range mountains.
The heavy rain could also lead to debris flows and landslides in NW Oregon & SW Washington. Johnson Creek, in SE Portland metro, is forecast to hit flood stage some time during the day Tuesday and could stay at flood stage through Wednesday.
Drier conditions are expected by Tuesday afternoon, which would improve any urban flooding. River flooding can take longer to subside and landslide risk may continue after the rain.
You can track river stages here: River Forecast
The KOIN 6 Weather Team will keep you updated.