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 December 2018
- El Niño conditions are considered to have persisted in the equatorial Pacific (see El Niño Outlook updated on 10 January 2019).
- Monthly mean temperatures were significantly above normal in Okinawa/Amami.
- Monthly sunshine durations were significantly below normal on the Sea of Japan side of northern Japan, on the Pacific side of eastern Japan and in western Japan.
- Monthly mean temperatures were extremely high from Okinawa region of Japan to Southeast Asia, around the Kara Sea, in and around southwestern Europe, from northeastern to western Australia and from southeastern to southern Australia.
- Convective activity was enhanced from the Bay of Bengal to the Indochina Peninsula and over the latitudinal bands of 10ºN over the central Pacific.
- In the 500-hPa height field, wave trains were seen from the North Atlantic to Japan with positive anomalies over southwestern Europe and from southeastern China to mainland Japan.
- The westerly jet stream shifted northward from its normal position from eastern China to the North Pacific.
- Stratospheric Sudden Warming was occurred in the Northern Hemisphere in mid-December.
Full version (PDF)
The descriptions until April 2011 are based on the old normal (i.e., the 1979 - 2004 average).
The descriptions until January 2014 are based on the JRA-25/JCDAS datasets.
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Tokyo Climate Center, Climate Prediction Division, 1-3-4 Otemachi, Chiyoda-ku, Tokyo, Japan.
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