Sleet “Drifts” In the Gorge

The west end of the Columbia River Gorge saw freezing rain during this weekend’s event, but once you got around Multnomah Falls there was a transition to snow.  This is very common with cold airmasses in the Gorge…coldest east of the Cascades and thinning rapidly west of Cascade Locks.  In this transition area, the cold air in the lowest elevations wasn’t quite deep enough to keep the snowflakes together up around 2,000-3,000′ or so.  So the snowflakes melted into raindrops.  Those raindrops then fell into the cold air stuck in the Gorge; but in this case it was so deep the drops had a chance to freeze into ice pellets before they hit the ground.  This is also sometimes called sleet, although the official definition is ice pellets.  I have also heard it called “tapioca snow” by road crews in that area in the past.  First time I heard that was 22 years ago…I’m getting old.

Anyway, this was one of those times where quite a bit fell between Bridal Veil and Bonneville Dam.  In past cases I have seen it occur in the same area.   These ice pellets easy bounce, slide, and roll down steep hillsides so they will form drifts (but not from wind) in gullies and other locations.  If they are deep enough, a plow can’t handle it and ODOT has to call in a snow blower.  That happened today near Multnomah Falls:


In 1996, when we had two back to back severe ice storms in the Gorge (2 days apart), the ice pellet drifts were massive, 10-20 feet high and blocked the old highway for many days.  There was very little snow, just ice pellets and freezing rain.  Here’s a picture of my (soon to be) wife standing in front of one…wow, 18 years ago in late December or early January that year.    This was just west of Multnomah Falls:


She didn’t approve me using this picture, but it’s okay, she doesn’t read the blog anyway.  Shhh!  Plus I don’t have any other pictures of the drifts.

Chief Meteorologist Mark Nelsen



22 Responses to Sleet “Drifts” In the Gorge

  1. Andrew (Near Silver Falls 1600') says:

    March is starting off damp here in the foothills. 2.81″ of rain the first 3 days of the month. Average for the month is around 9″.

  2. Jake-(Gresham) says:

    Had a high of 64F here today – just a great day all around. The birds were singing like crazy in the neighborhood and it was warm enough to wear shorts too. 🙂

  3. Claudeane Foster says:

    Always enjoy watching you Mark but wonder where Stephanie is?

    • Mark Nelsen says:

      Stephanie is staying home with her son and doing occasional shoots (stories about food) still for KPTV. Employed here but cut back hours quite a bit. She hasn’t been doing weather for about a month. That’s why we added Joe Rainieri onto the weekend morning show. Everyone else moved around a little.

  4. Jesse-Stevenson says:

    Checking in from the Gorge. I came home from a weekend at the beach to four inches of snow and about 1/4 inch of freezing rain on top of it yesterday evening. I-84 was a mess around Multnomah.

    Yesterday had a high of only 32 out here. Today made it up to 41 with some intense downpours in the afternoon. Even heard a rumble of thunder! There’s still a few inches of snow on the ground for now…

    • Andrew (Near Silver Falls 1600') says:

      I would have been upset had I been away and missed 4″ of snowfall. Especially if I had been at the beach since I do not really like the beach.

  5. pappoose in scappoose says:

    I really like the sleet “Drifts” pics Mark, seriously cool!

  6. Jason Hougak says:

    Mark you’ve been posting like a mad man! Just saw some of your yard footage. I immediately thought of you well back in those trees and lo and behold you post pictures of it. Those Hawaiian memories must be quickly fading back to reality. Thanks for the pix.

    • pappoose in scappoose says:

      Da Hawaiian pineapple express appears to be following him this week. Should keep da memories alive!

  7. Jason Hougak says:

    I remember as a 16 year old seeing those drifts. They lasted into spring in spots. We’ve been getting impressive rainfall here in foothills. Checked radar thinking this is a wide spread event. To my surprise it’s only bands setting up adjacent to the Cascades.

  8. weather lurker says:

    lol Mark. I don’t think any of us would want a picture from the mid 90’s posted on the world wide web. The 90’s are in the awkward phase of being old enough to not be cool and new enough to not be classic.

  9. Sifton says:

    & not to bag on ANYONE, but I always love the busts when it turns from crappy day to pleasant one instead! & HATE it when it rolls the other way……..

  10. W7ENK says:

    Uh oh. Apparently Winter isn’t over. Check this out…

    Arctic Blast 18z GFS HR 384

    MeteoStar GFS 16-Day Weather Forecast

    Looks really good to me, and I feel extremely confident that this one will verify! At the very least, I’m onboard with a significant cool down mid-month. This dovetails nicely with the latest EURO weeklies and the ensemble trends are encouraging. I fully expect models to come into agreement for this event at around 240 hours. At that point this pattern should be a lock!

    Let’s wait and see, shall we?… 😀

  11. Lurkyloo says:

    Crazy that those pics aren’t of snow. Also crazy how warm it was today after waking up to ice yesterday! Got me thinking about my garden!

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