The atmospheric river reached Portland on Monday morning, unleashing substantial rain across the region. This weather phenomenon is anticipated to significantly impact western Washington and northwest Oregon until Wednesday.
Weather Warnings and Flood Risks
The National Weather Service has issued flood watches for much of the affected areas. They caution that “widespread river, small stream, and urban flooding is likely.”
- People residing near steep slopes and canyons are at increased risk.
- Rapidly moving landslides and debris flows may pose danger to structures and roads.
Rainfall Predictions
In Portland, small streams and creeks are particularly vulnerable to flooding. The rain is expected to continue at a heavy pace.
- Between 1 a.m. and 9 a.m. on Tuesday, there is a 70-80% chance of receiving over a quarter inch of rain per hour.
- Coastal areas and the Cascades may experience even higher rainfall rates.
Rainfall Projections
The National Weather Service has provided forecasts indicating significant rainfall over the next three days:
| Rainfall Amount | Probability | Region |
|---|---|---|
| Over 4 inches | High | Oregon and Washington |
| Over 6 inches | High | Oregon and Washington |
Despite the heavy rain, snow levels are expected to remain high, likely staying around 8,000 feet. This means the atmospheric river will not contribute to significant snowfall in the mountains.
Residents are urged to remain vigilant and prepare for potential flooding as the atmospheric river continues to impact the region.
