Monthly Highlights on the Climate System

'Monthly Highlights on the Climate System' has been issued in PDF format since March 2007 as a monthly bulletin focusing on the monthly highlights of the monitoring results.

Highlights in March 2024

- Oceanic and atmospheric conditions over the equatorial Pacific indicate that El Niño conditions were gradually weakening (see El Niño Outlook updated on 10 April 2024).
- Monthly precipitation amounts were significantly above normal on the Sea of Japan side and on the Pacific side in eastern/western Japan.
- Convective activity was enhanced from the equatorial Indian Ocean to the tropical western South Pacific, and suppressed over the Philippines. In the lower troposphere, anti-cyclonic circulation anomalies straddling the equator were seen from the Maritime Continent to the western Pacific.
- In the 500-hPa height field, a wave train was dominant from North America to Central Siberia through Europe. Negative anomalies were seen from Japan to the Aleutian Islands.
- The polar-front jet stream exhibited a meandering structure from Europe to Central Siberia. The subtropical jet stream from Northern Africa to the seas east of Japan generally shifted southward from its normal position.

Full version (PDF)

Monthly Highlights on the Climate System (March 2024)
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The descriptions from May-2011 to April-2021 issue are based on the former climatological normal (1981-2010 average).
In the descriptions until April-2011 issue, 1979-2004 average is used as climatological normal unless otherwise stated.
The descriptions until January-2014 issue are based on the JRA-25/JCDAS datasets.
The descriptions from February-2014 to April-2023 issue are based on the JRA-55 reanalysis.

Figures and Tables

Notice: Products based on JRA-3Q were updated to those with improved quality in terms of tropical cyclone analysis. OLR-related products from January 1991 are based on NOAA CPC Blended OLR (CBO).

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Tokyo Climate Center, Climate Prediction Division.
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