Portland Forecast Shows 'Atmospheric River' Bringing Flooding

PORTLAND, OR – Portland the surrounding area will likely be rolling, rolling on the river starting Monday night. That is, rolling on atmospheric river that is traveling from the Pacific and head right to the area starting this evening.

The National Weather Service says that an atmospheric river is a long, narrow region in the atmosphere – "like rivers in the sky" – that bring water to the area.

How much water? "Roughly equivalent to the average flow of water at the mouth of the Mississippi River."

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Mississippi meet Oregon.

The National Weather Service's Portland office says that heavy rain should be moving into the area this evening bringing as much as 2.5 inches for the inland valleys, four inches along the coast, and up to seven inches for most of the higher terrain (where some of it could be snow).

Flood watches are in place for much of the area.

People should also be aware that heavy rain and high winds could also bring landslides and power outages. So, you might want to know where your flashlights are.

As for the rest of the week:

TUESDAY – Rain followed by showers with rain heavy at times. The good news is that the temperature should be around 50.

WEDNESDAY – Still a better than 50 percent chance of rain during the day. The high will be around 52 degrees.

THURSDAY – Chance of rain is 80 percent. High is going to be about 52 degrees.

FRIDAY – It starts to get colder. The high will only be around 45 degrees. Other than that, it should be partly sunny.

Graphic via National Weather Service's Portland office.