Atmospheric river set to blast the Northwest with rain and snow

An abundant amount of moisture streaming ashore from the Pacific will cause day after day of snow and rain from Nov. 20-22.

Transcript

00:00We are heading a little bit further west now, the northwest, where we are tracking rounds of rain and snow.

00:06This is going to be a high-impact storm. AccuWeather forecasts were more detailed and more actionable than those from other known sources

00:13in conveying how mountain snow could result in dangerous travel conditions in parts of the Pacific Northwest

00:18back on Sunday and Monday, including east of the Seattle metro. There's another storm coming.

00:23Our goal is always to help you stay safe, and we're going to give you the most advanced notice

00:27so you can make the best decisions for you and your family.

00:30Well, just for fun, with this western conversation, let's go all the way to the northwest.

00:34So here is the midday sun. This is as high as the sun's going to get in the sky today in Nenana, Alaska.

00:40This is kind of in south-central Alaska, snow on the ground there, a lot of cirrus clouds filtering that sun.

00:46This is as high as it gets. It's all downhill from here here for the next few months.

00:51And, well, there are no big storms up in that part of Alaska now.

00:54We've got a monstrous storm just off the west coast of the U.S. Look at this thing.

00:58We even have an eye-like feature sending an abundant amount of moisture into the western U.S.

01:03So this is absolutely an atmospheric river event. Sometimes it's debatable.

01:07People wonder, is it really an atmospheric river event?

01:09Well, this is clearly one that's going to be a high-impact event for the next several days,

01:14and we're getting into it here. So let's talk about some of the impacts.

01:17Satellite-radar combination passed several hours here. The core of the storm is way west of Portland right now,

01:24but the onshore flow is just like a fire hose directed at southern Oregon and northern California.

01:31That's where the heaviest rain will fall, and you're probably noticing that we have this deep, deep blue here

01:36over areas around Siskiyou County and all the way down into the area around the northern Sierras.

01:40So places like the I-5 Pass into northern California, around 4,000 feet or so,

01:47you're going to get hammered with some very heavy snow there. We're going to have many inches of rain,

01:51many inches of rain here in low elevations along the coastal range and down to the coast.

01:55Tomorrow, highs 49 in Medford. Steady rain, Portland, Medford, Seattle, San Francisco,

01:59getting into some significant rain there as well, specifically some of the heaviest rain.

02:04Medford down into Redding, California. You will have some rain into Seattle too,

02:08but the steadiest, really heavy stuff is going to be impacting Medford and other areas.

02:12Thursday, more of the same. We're looking at feet of snow in the mountains

02:16and some very heavy rain there, multiple inches. We'll have more details during our Big Three.