The Japan Agency for Marine-Earth Science and Technology, or JAMSTEC, is a Japanese national research institute for marine-earth science and technology
From the JAMSTEC Discussion:
“The latest observations indicate that there are weak signs of a La Niña. The SINTEX-F ensemble mean predicts that a La Niña Modoki will develop in the boreal autumn and persist into the boreal winter. However, there is a large uncertainty in the timing and amplitude of the event.”
Although it is a World forecast, it includes a forecast for North America since North America is part of the World. One might try to compare it to the NOAA Outlook we published yesterday which can be accessed HERE.
First, we take a look at the forecasted sea surface temperature anomalies (SSTA). JAMSTEC starts by forecasting the SSTA and Nino 3.4 Index on the first day of the month and from there it usually takes their models about two weeks to produce their seasonal forecast. I received it from JAMSTEC on May 14 close to when NOAA issued their Seasonal Update this month. The JAMSTEC model runs are based on conditions as of July 1, 2024. The NOAA Seasonal Outlook is based on conditions closer to the time when it was issued.
We do not have a full three-season forecast from JAMSTEC this month. We have forecast maps for ASO, SON and DJF so it is really a seven-month forecast as ASO and SON overlap a lot. For each of these three-month Outlooks, I also show the corresponding NOAA Outlook. The two are remarkably similar which is very unusual.
We also have single-month forecasts for August, September, and October 2024. I have a single-month outlook for August from NOAA but not single-month outlooks for September and October I did not show those comparisons.
Let’s take a look.
| This shows their forecast of sea surface temperature anomalies at three points in time. Blue is cold and is associated with La Nina if it occurs in the Nino 3.4 measurement areas. You no longer can see the El Nino tongue of warm water extending from Peru to the west in the ASO image but look at that blob of cool (anomaly) water to the west i.e. by this point in time this has Modoki characteristics that impact the Walker circulation. SON and DJF also show La Nina but are increasingly to the west and may not be in the Nino 3.4 measurement area. I have written about that before. It raises questions about the reliability of our current approach to thinking about the ENSO Cycle. This is covered in another article that can be accessed HERE. But JAMSTEC is showing a relatively normal ocean off the coast of much of the U.S. coasts which probably explains their forecast.
Of interest also is the cold water of the West Coast of the U.S. and the warm water between Africa and the north coast of South America which can support tropical storms and hurricanes. JAMSTEC uses the same definition of Normal (climatology) as NOAA. JAMSTEC does a better job at characterizing La Ninas and El Ninos than NOAA. JAMSTEC provides me with a lot of other information that I do not include in my articles to keep them to a manageable size for readers. That material is the atmospheric pressure patterns. |
Some Readers will have to click on “Read More” to read the rest of the article which you need to read to see the forecasts. I can only include a certain amount of material in the lede.
Then we look at three forecasts. As discussed earlier, JAMSTEC tries to work with meteorological seasons and this month it does not line up perfectly since we have ASO, SON and DJF. Next month it will line up perfectly.
Now we look at the three seasonal forecasts.
| The above covers August/September/October
“The SINTEX-F predicts that most parts of the globe will experience a hotter-than-normal condition in the August–October average (especially the northern part of the South American Continent), except for the northwestern parts of the North American Continent, some parts of Central America, most of Argentina, southern Chile, a central part of Africa, southern Asia, Indonesia, northern Europe, and western Russia. In contrast, some parts of Alaska will be colder than normal. ” “As regards the rainfall in the August–October average, a drier-than-normal condition is predicted for the central USA, California, many parts of the South American Continent, and West Africa. On the other hand, Alaska, some parts of Canada, Florida, Central America, the Caribbean, central Africa, India, Nepal, Bhutan, most of Indochina, the Philippines, Indonesia, East Asia, and northern Europe, and some parts of Russia will be wetter than normal. ” “In the August–October average, the model predicts that most of Japan will be hotter and wetter than normal. “ |
NOAA Precipitation Outlook for this period.
| The JAMSTEC Outlook looks a lot like the NOAA Outlook. |
Sep/Oct/Nov
| The above covers September/October/November 2024 which is Fall or Autumn as you prefer.
Here is the interpretation from the JAMSTEC discussion: “In the boreal autumn, the SINTEX-F still predicts warmer than normal conditions for most of the globe, except for western Canada, western USA, some parts of Argentina, some parts of central/northern Africa, India, and western Russia. Some parts of Vietnam, northern India, and Indonesia will be colder than normal.” “In the boreal autumn, drier-than-normal conditions are predicted for California, many parts of the South American Continent, some parts of Asia, Italy, and some parts of West Africa. In contrast, wetter-than-normal conditions are predicted for Alaska, some parts of Canada, some parts of Central America, the Caribbean, eastern Australia, some parts of central Africa, India, Nepal, Bhutan, some parts of Indochina, the Philippines, Indonesia, and some parts of East Asia.” “In the autumn, the model still predicts that most of Japan will be warmer. Some parts of southern and northern Japan will be wetter.” |
NOAA Precipitation Outlook for this period.
| The JAMSTEC Outlook looks a lot like the NOAA Outlook but drier in parts. |
| The above covers December/January/February which is Winter.
JAMSTEC does not provide a commentary for the third season map but the reader can interpret it themselves.
|
NOAA Precipitation Outlook for this period.
| The JAMSTEC Outlook looks a lot like the NOAA Outlook but the Southern Tier dryness is more pronounced. |
Now I am going to provide their single-month forecasts for August, September and October 2024.
| The above is the single month of August 2024. It is interesting as a world forecast but since the U.S. is part of the world it also provides a U.S. forecast. |
| The above is the single month of September 2024. It is a world forecast but you can clearly see the forecast for the U.S. |
| The above is the single month of October 2024. |
Now we look at the key indices used by JAMSTEC in making their forecast. Perhaps I should have presented these first.
| This forecast is for a marginal La Nina which is different from what NOAA is forecasting. |
| I am showing the Modoki Index this month. This index shows that by Fall, the La Nina will take on Modoki characteristics. If I remember correctly this impacts Eastern Asia more than the U.S. |
And here is the short JAMSTEC Discussion which I have already included with each of the seasonal forecast maps.
ENSO forecast:
The latest observations indicate that there are weak signs of a La Niña. The SINTEX-F ensemble mean predicts that a La Niña Modoki will develop in the boreal autumn and persist into the boreal winter. However, there is a large uncertainty in the timing and amplitude of the event.
Indian Ocean forecast:
A higher than normal temperature is present in the tropical Indian Ocean, indicating a positive phase of the Indian Ocean Basin Mode. Meanwhile, warmer temperatures in the east suggest the development of a negative phase of the Indian Ocean Dipole. The SINTEX-F predicts that a weak negative Indian Ocean Dipole will develop in the boreal autumn. This is different from last month’s prediction of a positive Indian Ocean Dipole in the boreal summer.
Regional forecast:
The SINTEX-F predicts that most parts of the globe will experience a hotter-than-normal condition in the August–October average (especially the northern part of the South American Continent), except for the northwestern parts of the North American Continent, some parts of Central America, most of Argentina, southern Chile, a central part of Africa, southern Asia, Indonesia, northern Europe, and western Russia. In contrast, some parts of Alaska will be colder than normal. In the boreal autumn, the SINTEX-F still predicts warmer than normal conditions for most of the globe, except for western Canada, western USA, some parts of Argentina, some parts of central/northern Africa, India, and western Russia. Some parts of Vietnam, northern India, and Indonesia will be colder than normal.
As regards the rainfall in the August–October average, a drier-than-normal condition is predicted for the central USA, California, many parts of the South American Continent, and West Africa. On the other hand, Alaska, some parts of Canada, Florida, Central America, the Caribbean, central Africa, India, Nepal, Bhutan, most of Indochina, the Philippines, Indonesia, East Asia, and northern Europe, and some parts of Russia will be wetter than normal. In the boreal autumn, drier-than-normal conditions are predicted for California, many parts of the South American Continent, some parts of Asia, Italy, and some parts of West Africa. In contrast, wetter-than-normal conditions are predicted for Alaska, some parts of Canada, some parts of Central America, the Caribbean, eastern Australia, some parts of central Africa, India, Nepal, Bhutan, some parts of Indochina, the Philippines, Indonesia, and some parts of East Asia.
In the August–October average, the model predicts that most of Japan will be hotter and wetter than normal. In the autumn, the model still predicts that most of Japan will be warmer. Some parts of southern and northern Japan will be wetter.
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| I hope you found this article interesting and useful |
