January 30, 2017

Another Cold, Snowy, and Icy Period Will Hit Portland AGAIN

You have to feel sorry for the folks living around Portland and the Columbia Gorge.   They have suffered from snow, freezing rain, strong winds, and ice. And according to the latest models, their suffering is not over, with more wintry weather coming later this week.  And yes, those cold-buffeted folks in eastern Washington should get ready for the chill as well.

If I was the Mayor of Portland I would order some salt and be ready so spread it BEFORE any snow hits.
Portland Oregon Needs This

Here is the latest high resolution forecasts (and yes, there is still considerable uncertainty in the forecast).

To get snow and freezing rain, one needs cold air.  That is coming, starting tomorrow.  The following are a series of forecast maps from the UW high resolution prediction system, showing sea level pressure (solid lines) and temperature (shading, blue is cold).

4 PM Monday:  mild (green color) air over most of the region.

 4 PM Tuesday, an influx of cold air is occurring in Washington, northern Idaho, and Montana.
 Cold air is in place east of the Cascade crest and a very large difference in pressure have developed across the Cascades.  Strong easterly winds would be occurring in the Columbia Gorge.

 Thursday, 4 PM.  Little change east of the Cascades but warmer air to the west.
So plenty cold for snow east of the Cascades.  Cold air in the Gorge and over the eastern side of Portland. Windy and cold in the Washington Cascades passes.

On Thursday and early Friday an area of precipitation will move northward into the region (see the 24-h precipitation ending 4 AM Friday  For most of the west, this will fall as rain, but in the Gorge and immediately downstream of it,there could be snow and freezing rain.
The 24h snowfall prediction ending 4 AM Friday suggests this...and if anything the model is probably underplaying the cold air coming through the Gorge.  Substantial snow along the eastern slopes of the Oregon Cascades.

It is too early to have too much confidence in this snow forecast, but the cold air east of the Cascades is pretty much a sure thing, as is some frozen precipitation in the Gorge.   Keep tuned and don't hold the salt if you are in Portland.


  1. Portland's mayor will probably get more votes in the next election for NOT using salt on the roads. NaCl, a deadly poison to all right-thinking (or is it left-thinking?) progressives.
    OT, it looks like California's drought is about over.

  2. It could be worse - residents of Hood River must be exhausted. Stunning how much snow/ice they have had, and it's surprising that more damage has not occurred.

  3. FYI, The City of Portland did test road salt vs the magnesium chloride they have been using and found it to be no better: http://www.oregonlive.com/weather/index.ssf/2017/01/portland_test_finds_road_salt.html

  4. Bob...they used the snow WRONG. They put it on AFTER it snowed. It is critical to put it on BEFORE it snows..cliff

  5. Relax folks, just hunker down and wait it out just like we have done for thousands of years. It won't hurt you a bit to sit still and watch it snow. Please Cliff keep your salt for the Sounders, were a fresh water port.

  6. I love the Portland article where they say salt works the same as de-icer. The reality is that all the de-icers are chloride salts, but you can get them in sodium, magnesium and calcium varieties. The basic difference is that they work slightly differently at different temps. They all dump cations into the environment. They all lower the melting temperature of water.

    NaCl is best at temps near freeing, while MgCl is better at lower temps (like zero). Most of our road freezing occurs with temps in the high teens to high twenties which says NaCl.

    The discussions of the specific form of salt are a waste of time. The real issue is how and when its applied and how cold the road surface is at the tine of application. Most importantly, whether the city uses a prevention philosophy (very effective) or they use salt to help their equipment remove ice and packed snow later (not as effective). But its all salt.

    So why don't we shift the discussion to How and not What. Can't believe Portland didn't understand that, but then, Seattle didn't used to either. But if you go to the upper Midwest, every road department understands this stuff. Oregon is acting like its inventing something new.

  7. Bob says, "The City of Portland did test road salt vs the magnesium chloride they have been using and found it to be no better".

    It was NOT a "test" in any sense of the word as it applies to any legitimate measurement or comparison. I was a typical inept Portland ruse of no value but to invent a fallacious reason to keep pretending as though they are preventing vehicle, road, bridge and environmental damage.
    If they were ever genuinely interested in learning the impact of the very infrequent use Portland would need officials need only look for said damage right across the river where salt has been used for decades in Clark County Washington.
    But that would require honest public officials and this is Portland and Oregon.

  8. Vicki,

    NaCl hardly qualifies as deadly poison. Sea air deposits on the order of 1 gram per day of salt to the ground in seaside areas. While it's true that too much salt stunts trees and other plants, we couldn't live without salt.

    Or we could use potassium chloride on the roads, which is a (natural) fertilizer...

  9. We're finally getting a real winter in the NW.


  10. I don't feel sorry for Portland. I lived there a while. It's much more seasonal than the Sound. And that means much nicer summers too. It's a great city that like any city has its flaws and gems.

  11. It appears that at least some of the saner heads in Portland are finally getting the message:


    It's not much at all for an alleged "test" run, but at this point I'll take anything, given the nightmares the roads have become during this winter.


Please make sure your comments are civil. Name calling and personal attacks are not appropriate.

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