May 15, 2022

La Nina is Not Going Away. What does the mean for this summer's weather?

 It is now clear that La Nina is not going away, and may hang around into next winter.   

Cold water is entrenched over the central and eastern tropical Pacific (the definition of La Nina) and the latest forecast model runs suggest a continuation into fall.

Several of you have asked:   what does this imply for our summer weather?

Let me tell you.   

But first, the bottom line:   the summer effects of La Nina are modest, but will push the western side of our region towards cooler than normal conditions.

The Impacts

During La Nina years, sea surface temperatures off the West coast are usually cooler than normal, and those cooling effects spread inland. 

 To illustrate, here is the sea surface temperate difference from normal for the summer months (May through September) for La Nina years.    Blue colors are cooler than normal.

And if we average surface air temperatures for La Nina summers and subtract those temperatures from normal, we find that cooler than normal summer temperatures (e.g., green colors in the figure below) occur from California to Washington during La Nina summers (temperatures anomalies in degree C are shown below).


In contrast, West Coast precipitation is hardly changed...perhaps slightly drier on the western sides of the Cascades.  I suspect this is because the colder water works against thunderstorms.  Interestingly, La Nina seems to have more summer impact over the Midwest U.S.



Summer versus Winter

La Nina (and El Nino) have far more impact on West Coast weather during winter and early spring than summer.    The atmosphere is far more active during the cool season, with stronger, more active flow in the midlatitudes and more interaction between the tropics and midlatitudes.

A Record-Breaking Spring

As I will detail in a future blog, we are on track to "enjoy" the coolest spring in a half-century.  Right now, the average April/May high temperature at SeaTac is the second-lowest in the past 50 years (see below).  And there are a lot of cold temperatures ahead.


And at Yakima, this spring IS the coldest by far.


La Nina gets part of the blame...but not all.

And I hate to tell you this.... record-breaking cold will be returning later this week.  So don't put your sweaters away yet.

17 comments:

  1. Cliff, last summer was a la Nina season from the data I saw on the cpc website and it was one of the hottest summers in record so why should we expect this summer to be cooler than normal?

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    Replies
    1. Tim...that is not correct. La Nina weakened last summer. The Nino 3.4 index went to near zero. Very different than this summer. Please go to the Climate Prediction Center ENSO weekly presentation to see the graphics..cliff mass

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    2. Tim, you see it here: https://www.cpc.ncep.noaa.gov/products/analysis_monitoring/enso_update/ssta_c.gif
      Sea Surface temperatures during late Spring/early Summer rapidly rose, espeically relative to normal, actually briefly getting above normal. And that probably began in Spring, though the graphic doesn't go that far back. And that is perfectly normal for La Nina, even if it returns the following winter (which it did), it normally weakens during that time period. But this Spring has been quite unusual in that the Nina, after briefly weakening late Winter, has actually intensified during the Spring. I don't remember the last time that happened.

      Delete
  2. Hey Cliff! Thanks for the info. How does this compare to that cold & wet spring we had a couple years ago?

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    Replies
    1. 2017 was a cold wet la Nina spring then the following summer was hot especially July and August.

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    2. Tim.... that is not correct. The summer of 2017 was NOT La Nina. Sea surface temps were actually above normal!..cliff

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    3. Tim, you're getting a number of things wrong today, perhaps you should read some of Cliff's past postings on La Nina and El Nino effects on the PNW.

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    4. Yes, you are correct I see that now, thanks.

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  3. I'm curious as to flooding risk and how late we can expect summer alpine hiking to be snow free. At this point there hasn't been any melting so if we have a large snowpack during the hottest time of the year (July). Flooding in July?

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  4. Models aren't reality. We'll see. If it means the west doesn't burn this summer, I'm all for it.

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  5. I just found story this a few minutes ago. Dr. Mass: I would be interested to hear what your opinion is about their conclusions.

    https://phys.org/news/2022-05-hidden-backstory-deadly-pacific-northwest.html?utm_source=join1440&utm_medium=email

    ReplyDelete
  6. I've been interested in the SnoTel data at Paradise this spring. It's currently significantly in excess of both the plotted median and 30 year average as displayed on the NWRFC graph for the Paradise collection station. The next several days will likely see an increase in both snow depth and snow-to-water equivalent.

    https://www.nwrfc.noaa.gov/snow/snowplot.cgi?AFSW1

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    Replies
    1. I've been following SnoTel as well for years now, wonder why it's never alluded to regarding the MSM reportage on drought conditions.

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  7. If we all just be a little more patient and give us more time to observe, I think we will see the Earth perturb itself into new trends and equilibriums.

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  8. With the way the weather pattern seems to be going, is this similar to the La Nina we had in 2011? I remember that summer because I did DOT work up in the mountains and temperatures still were in the 40s and we didn't hit or exceed 85 degrees until the latter part of August.

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  9. Hi Cliff - more interested in your take on the 2022 corn crop failure across the Great Plains of North America, similar to 2019. We called this situation correctly 20 years ago in 2002 - natural, solar-driven global cooling starting by~2020..
    https://wattsupwiththat.com/2022/05/11/the-recent-decline/#comment-3515361
    Told you so! We've been predicting this slow-motion train wreck since 2002.
    This is ending badly. I would much rather have been wrong.
    [Insert very strong expletives here]

    COLD SPRING KEEPING N.D. MOSQUITOES AT BAY–FOR NOW; PRIME CORN YIELD ALREADY GONE; ‘BLUE BLOB’ HAS HALTED ICELAND/GREENLAND MELTING; + SULINA CANAL RESTRICTED
    May 12, 2022 Cap Allon
    Zelenskyy has again urged the international community to stop the Russian blockade of the deep seaports of Ukraine citing the threat to the world food supply.
    [excerpt]

    PRIME CORN YIELD ALREADY GONE

    Corn farmers across the much of the U.S. are unlikely to net high yields this year because their planting has been delayed significantly by cold and rain, according to an Iowa State University agronomist.
    The impact of that delay will depend heavily on farmers’ progress over the next 10-14 days. If the weather doesn’t play ball (which, going by the chart above, it doesn’t look like it will) then it’s all by game over for U.S. corn.

    Mark Licht, an ISU Extension cropping systems specialist who studies yield trends, believes that the current delays have already reduced yields: “I think we’ve already taken the top end off of it. How much is yet to be determined.”

    Heading into this week, corn planting across the state was about two weeks behind the five-year average, the slowest planting pace since 2013, said Greg Thessen, director of the USDA’s National Statistical Service for the Upper Midwest.

    Just 14% of seed corn was in the ground as of Sunday –thanks to persistent rains since the middle of April and cold soil temperatures– compared with the average of 63%. The ground needs to average about 50F for proper sprouting, yet we still have many regions having to contend with hard frosts.

    The best corn crops are planted before mid-May, and that it’s all-but game over if planting pushes into June.

    SCIENTIFIC COMPETENCE – THE ABILITY TO CORRECTLY PREDICT October 20, 2021. Update May 12, 2022
    https://correctpredictions.ca/
    “The ability to correctly predict is the best objective measure of scientific and technical competence.”
    Our scientific predictions on both Climate and Covid are infinitely more accurate than the mainstream narratives, which have been false and baselessly alarmist to date.

    ReplyDelete
    Replies
    1. Whoa...what? "All-but game over"? The author complains about alarmism in MSM, yet includes it in his own post.
      Bunk. Please find real sources of information.

      Delete

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