February 03, 2022

January Was No Month for Vacation in the Columbia Basin

Cold, with temperatures generally remaining below freezing.

Cloudy almost all the time, with very little sunshine

Icy, with freezing fog on many days.

Some location in the interior of Alaska?    Siberia?

No, the Columbia Basin of Eastern Washington.

Day after day, cold air and associated low clouds pooled in the Columbia Basin (see imagery below on January 28th)

WSDOT highway cams show fog and low clouds nearly every day (see an example for January 14th below)

With the unending veil of clouds, the temperature stayed nearly constant and cold--close to freezing for extended periods.

Below is something amazing...and disturbing.  The temperatures at Patterson in Benton County.  For more than half the month, temperatures were between 30 and 35, with many days showing almost no diurnal (daily) variations.   Just constant murk, cold, and freezing fog.  Very unpleasant.  I would take 20F and blue skies any day over that.

Even more depressing is the solar radiation measurement, with many days remaining less than 100 W/square meter).  Several near 50.  Full sun is around 450 by the end of the month.

On many days, Seattle (not known as the winter mecca of sun loves) had considerably more sun.

Ironically, there are several solar projects completed or planned for eastern Washington...they should not expect to generate much electricity in mid-winter I suspect.

Why is the Columbia Basin so cloudy and cool during the winter?   

Because it is a basin, in which cold, dense air collects (see terrain map).  Cold air can enter through the Okanagan Valley or can be generated on the surrounding slopes (by infrared radiation to space) and then settles into the lower elevations of the Basin (cold air is dense and tends to sink).  The Columbia Basin has only one real exit....the Columbia Gorge... and that is quite narrow, limiting its ability to "drain" the cold air in the Basin.

Warm air from the west often overrides the cold air of the Columbia Basin, producing a strong inversion, in which temperature increases with height.   This structure is illustrated by vertical sounding at Spokane during the morning of January 13 (below).   Inversions prevent mixing of air in the vertical, which further "protects" the low-level cold air.

But it is even worst than that!   The low-level low clouds within the Columbia Basin tend to radiate infrared energy to space, further cooling the near-surface frigid layer. It is like having a refrigeration unit on top of the low clouds.

The  Columbia Basin cold pool has some other unpleasant issues.   Subfreezing air near the surface can foster freezing rain and ice storms, when warm rain falls into the cold air and is supercooled to below freezing.  And the inversion can separate strong winds aloft from "dead air" within the cold pool.  The result can be strong wind shear (large changes of wind with height) that results in considerable low-level turbulence--producing a bumpy ride for aircraft landing in towns such as Richland and Moses Lake.

Because of the persistent cold air in the Columbia Basin, the climatology of the region is one of great extremes.   

Consider the average temperatures by month in the Tri-Cities. (below).  December and January are cold, with temperatures averaging in the 30s.  This is the season of the Columbia Basin  low-level cold pool.  But something wonderful happens in February.  Increasing sun finally has an impact, warming the surface, increasing vertical mixing, and weakening/destroying the cold poor. Temperatures surge.  

By March the cold pool is history and the Columbia Basin becomes warmer than western WA.  

Courtesy of Weatherspark


  1. Based on my observations as a weather-obsessed individual who has resided in the Columbia Basin for over 30 years, "fog season" (period of time when we can experience persistent fog/stratus) begins when the length of day drops below 10 hours and 20 minutes, combined with a maximum sun angle of 31° (above the horizon at noon). That starts on around Oct 27, and ends around Feb 14. There's more than one reason to celebrate Valentines Day over here. It had actually been a relatively low fog year until January..

  2. Thanks for touching on this topic, Cliff. I've been wanting to ask you about weather conditions that flatline temperatures. We usually concentrate on large temperature swings rather than the absence of same. I remember the big NW ice storm 20-25 years ago. Seems like the temperature sat between 28 and 30 degrees for several days. Similar inversion, I suspect. Are there other atmosphere conditions that flatline temperatures, maybe extreme cold? (Aside: What conditions are necessary for the super lightning bolt that set a record a few days ago in the SE?)

  3. Some of the worst visibility I've ever experienced was driving home to the West Side while going to school at WSU in Pullman. In fact when freezing fog was in the forecast, I would often drive north on US-195 to the town of Steptoe, and take Hwy 23 to I-90 at Sprauge. This route bypasses the 130-mile Hwy 26, which runs from Colfax to Vantage, and is only a 2-lane road.

  4. January was the pits in Hood River.

  5. Last year around this time the Columbia River Gorge winds really ramped up, and combined with an approaching cold front caused a massive ice storm throughout the Williamette Valley. My neighborhood was without power for over three days, with many other areas being dark for over a week. Coupled with the massive wildfires that had occurred earlier in the previous Fall, it was a nasty one - two punch.

  6. I totally concur with your blog, Cliff. My wife and I just moved to Quincy from Tacoma (60 years on the west side) in June 2021, and have experienced both extremes the Columbia basin has to offer. We still have snow on the ground from the January 6th snow storm! We love it here, though.

  7. Cliff: I've long wondered why the Sichuan Basin in China has such awful, rainy weather, even though it's far from either ocean. (Yet it seems the Tibetan-Qinghai plateau to the west can be much sunnier.) Is this the explanation?

  8. I live on the Naneum Fan, about 5 miles NE of the Ellensburn Airport (KELN).
    The elevation is 2,240 feet.
    The last bit in the post shows averages.
    I think the actual high in June (?) was 116°F and the
    December low (at my house) was about -3°F.
    There was a 24" snowfall in early January. It is still here.
    Yes it did compact a bit.
    Thanks Cliff.

  9. Even though it was persistently cloudy and cool in Wenatchee this January, the average temperature for the month actually ended up slightly above the long term normal based on the long term record from the Tree Fruit Research Center. And despite the record one-day snowfall of 24", the total snowfall for the season is only a few inches above the long term seasonal average at the TFRC. (38")
    It would be interesting to compare the average January temperature at a high elevation station, that was mostly in the warmer air above the inversion, with its normal January temperature, since I think you would find that it was considerably above normal for this January.


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