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 October 2021
- La Niña conditions are considered to be present in the equatorial Pacific (see El Niño Outlook updated on 10 November 2021).
- In Japan, temperatures were above normal in the first half of the month but below normal afterward. Monthly precipitation amounts were significantly above normal on the Sea of Japan side of northern Japan.
- Monthly mean temperatures were extremely high from the northeastern part of North America to the central part of Central America and from northern to eastern Australia.
- Convective activity was enhanced over the latitude band of 10°N to 20°N from India to the central North Pacific, and suppressed over the western tropical Indian Ocean and the western to central equatorial Pacific.
- In the 500-hPa height field, a wave train was dominant from the mid-latitude North Pacific via northern North America to the Mediterranean Sea, with significantly positive anomalies over northeastern Canada.
- The subtropical jet stream over Eurasia shifted northward from its normal position. The westerly jet stream over the mid-latitude North Pacific also shifted northward from its normal position.
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.
Figures and Tables
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