March 11, 2019

Record-Breaking Cold in Eastern Washington

The cold that has been experienced in eastern WA  since early February has been totally amazing.  And unlike western WA they have had little relief the past week.

You will not believe the minimum temperatures this morning (see below).  Yakima got down to 7°F, with a number of locations around Ellensburg dropped to 2-3F. 

Such temperatures are unusual this late in the season, as shown below at several sites in northeast Oregon and southeast WA.  Some of the daily low temperature records were smashed by 5-8F.  That is significant.

Want to be really impressed?  Yakima set a new record for coldest temperature so late in the season with 7 F today.  Prior to 2019 the temperature had never dropped lower than 13 F this late in the season.

Today marks the 4th consecutive single-digit minimum temperature at Yakima with 7, 7, 4, and 7 F.  Over the past month, Yakima's highs have been hanging around the normal lows, with temperatures dropping below 10F on roughly 1/3 of the days.
Even worse was Pasco, where the highs on several days did not get even near the normal lows.
Over the last week, the departure of the daily average temperature from normal has been stunning east of the Cascades crest, with much of eastern WA more than 16F below normal.

An interesting aspect of the cold air is how shallow it was.  As suggested by the minimum temperature map, the coldest temperatures were at low elevations, with warmer air above. This structure is suggested by the radiosonde (balloon-launched weather station) observation at Spokane for 5 AM Monday, which shows cool air near the surface topped by a strong inversion (temperature warming with height).  So a modest hike to higher elevation would bring much warmer tempeatures.

In this plot, temperature is the right line and dew point temperature is the left line.  
Heights are in pressure (850 is roughly 5000 ft).

Why do cold?  We start with unusually extensive snow cover for this time of the year, with snow producing cooling by reflecting solar radiation back to space and through emission of infrared energy away from the surface.

A satellite picture shows the total snow cover over eastern WA today.

With virtually no cover over the Columbia Basin a year ago.

And the general weather circulation pattern has been highly anomalous, with ridging offshore and a trough of low pressure and cold air over us for most of the past 30 days (see the upper level height anomaly below, with the purple being more lower heights/pressures).

The extreme low  temperatures in eastern Washington have already killed thousands of cattle and winter wheat emergence has been slowed.   Fortunately, major warming is in store during the next few days, with highs moving into the 40s and low temperatures rising into the 20s or more.


  1. Spokane(GEG) still has 12" of snow on the ground,with another 3-4" expected tomorrow.Despite the upcoming warming trend this weekend,nighttime temps
    there will still remain well below normal because of the snowpack and strong radiational cooling.The snow will be melting very slowly,which actually be good, since there is a flood threat if it melts too quickly.
    If we think temps are cold in Washington,many Montana stations are running 28-30 degrees below normal so far in March!
    It would be interesting if the state climatologist office could do some research regarding this stretch of consecutive days with below normal average temps for various weather stations in the state.It's approaching 40 days now,which must certainly be one of the longest streaks--certainly in modern post WW2 time period--since records started to be kept over 100 years ago.

  2. We drove back from the Gingko Petrified Forest yesterday, where it was around 30 in the afternoon. Driving west through Kittitas at dusk, the temps were dropping steadily to about 20 midway between Ellensburg and Cle Elum, and I thought for sure it would be really cold up at the pass. Surprised to see it was 30 in Cle Elum where we stopped, and then actually RISING temps as we ascended in altitude, so it was 34-35 up at Snoqualmie Pass, then steadily warmer as we descended on the other side. Must have been an inversion layer on the east side of the mountains?

  3. My mother and grandfather live a few miles west of Ellensburg and as of Saturday when I was last there, they still had 19-20 inches of snow on the ground. Both mornings I was there the lows dropped into the single digits, Friday morning getting down to 1.8. And there have been several days where it dropped below zero there since the cold began. Daytime highs have been just getting into the low to mid 20s most days lately at their place, with a pretty persistent layer of fog and low clouds some of the days. There's definitely an inversion, as I hike Manastash Ridge whenever I'm there, and this last trip it felt easily 10-15 degrees warmer at the summit than at the trailhead(approx 1700 foot elevation difference). And hiking above the cloud deck made for beautiful photos. Cliff, I'd love to hear an explanation in a future blog about the atmospheric conditions that have to be present to create the fog and low clouds that are sometimes so persistent and trap the cold in the Kittitas Valley in winter. I realize it is typically when there is high pressure, and seems more prevalent the more snow is on the ground. I can remember times where it would be sunny and 50-60 degrees on surrounding peaks, while being in the teens in the valley beneath the clouds. Would love to hear a more scientific explanation of this phenomenon. Thanks for the great blog!

  4. You might have mentioned that many of the long range forecasts for February, including the CFSv2, IMME, NMME and ECMWF all forecast above average temps for the Pacific NW last January and remained posted as such even through mid February.

  5. just curious, Cliff, if the extended hyper-cold throughout the north-western tier is going to impact the ongoing pine-bark beetle infestation?? I think cold weather is anathema to those guys...

  6. Woke up to fresh snow on the ground again this morning. Near Beaver Lake in Sammamish.

  7. Replies
    1. Well, that didn't take long. Standard "I have a snowball in my hand, so climate change is impossible" ignorance. I guess there has to be at least one of those types of comments on every single page that involves a discussion about the weather.

  8. I wonder if the albedo effect presents a positive feedback mechanism where cold and snow reinforce each other, causing a sudden shifts in climate in the cooling direction.

  9. Heck, I'm on the western side of the Cascades, got 4" MORE snow Monday night, and it's still coming down. I don't know which gods to sacrifice to at this point...

  10. Has it been much colder in Western Washington as well vs. last year? PSE just sent me a notice that my gas usage was projected to be 31% higher than 3/2-12 last year. Since gas only heats my water and hydronic baseboard heaters, and my thermostat is similar to last year, I am wondering if the difference is just that temps have been colder. I have tried to get day-by-day data, but the NOAA website only provides summaries for the time period

  11. I'm very curious about the blizzard of February 9/10 that decimated the dairy farms in the lower Yakima Valley. It sounded like the forecasts underestimated it and the severity of it was in a small area. I gained a lot from Mr. Mass' analyses of the California and Arizona windstorms and wonder if this was freaky enough to warrant a similar kind of analysis.

  12. Sounds like a good fire season this year, a big relief compared to the past two smoke - filled summers.

  13. that's what happens when you lose multi-year ice, the jet stream goes haywire and we have polar vortexes stumbling around....

    Polar Vortex, Jet Stream, Climate Change and Cold Snaps

    article here:

    Jennifer Francis: A New Arctic Feedback

    and here:


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