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.
Notice: From 19 May 2021 onward, the products in this page are based on the new climatological normal (1991-2020 average) unless otherwise stated.
Highlights in September 2021
- Though ENSO-neutral conditions persisted (see El Niño Outlook updated on 11 October 2021) negative SST anomalies were observed from the central to eastern part of the equatorial Pacific.
- High pressure systems frequently covered northern Japan and that condition brought a record-breaking long sunshine duration to the Sea of Japan side of northern Japan.
- Monthly mean temperatures were extremely high from the northern Korean Peninsula to the northern part of Southeast Asia and in the central part of North America. Monthly precipitation amounts were extremely high in central China.
- Convective activity was enhanced from southwest of Sumatra to the Maritime Continent, and correspondingly easterly wind anomalies were dominant from the western to central equatorial Pacific in the lower troposphere.
- The subtropical jet stream shifted northward from its normal position over Eurasia.
Full version (PDF)
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.
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