NORTHWEST - Monday through Wednesday, we will see a series of strong atmospheric rivers bring very heavy rainfall, warmer temperatures, and high elevation snow that will be measured in feet. Flood potential is increasing, especially for river flooding, as the week rolls on.

Mon - Wed

A deep supply of tropical moisture arrives Monday from the "pineapple express," or atmospheric river. Intense rainfall, gusty winds, and heavy mountain snow are expected. The ridge of high pressure helping to steer the tropical moisture northward will also lead to above-average temperatures, bringing snow levels up in elevation for Washington, Oregon, and Idaho.

With this event being so warm, significant flooding is likely for the higher terrain of the Cascades, in addition to lower elevations! Flood Watches have been issued for Washington until next Friday. Rainfall totals through Thursday are expected to top 7-12 inches for large areas along and west of the Cascades. With heavy rainfall rates, we could see flash flooding develop in addition to river flooding.

As all of the moisture adds up and runs off into creeks, streams, and rivers, water levels will rise dramatically through the middle of the week. Many rivers are expected to reach moderate to major flood stages, including the Snoqualmie and Snohomish.

Moisture will great increase through sunrise Monday, with intense rainfall rates. As this moisture moves east and hits colder air in the Rockies more of the rain will turn to heavy snow. Temperatures will continue to climb, leading to higher and higher snowfall levels. A break arrives toward Wednesday evening and Thursday. Another weaker system is expected on Friday.

Snow will be very heavy east of the Cascades, especially above 6,000 feet. Snow levels will go up and down quite a bit through the event, so driving over mountain passes in the afternoons may yield only rain at times, while at other times intense snow is expected. The Cascades in Oregon are expected to see snow only at the highest elevations.

For more details, be sure to join us at :50 past the hour!