Island Climate Update 29 - February 2003

Tropical cyclone update
The tropical cyclone outlook for the current moderate El Niño season (2002/2003) forecasts an eastward spread in cyclone occurrence, with more cyclones than normal expected east of the dateline, and somewhat fewer than normal in the west.

Forecast validation
Forecast period: November 2002 to January 2003
The El Niño related region of enhanced convection over Western and Eastern Kiribati was expected to persist, resulting in continued above average rainfall there, and above average or average rainfall in Wallis and Futuna, Tuvalu, and Tokelau. A tendency towards below average rainfall was expected from Papua-New Guinea east-southeast to the Austral Islands, including New Caledonia, Fiji, Vanuatu, Tonga, Niue, and the Southern Cook Islands.

ENSO and Sea Surface Temperatures
El Niño fading and likely to return to neutral state by late autumn of 2003
Equatorial Pacific SSTs weakened during January
The El Niño event has peaked and is waning. There was noticeable cooling of SSTs off the South American coast during the month.
The NINO3 SST anomaly was weaker in January than in December (now +1.1°C), while NINO4 was constant at +1.3°C. Three month (November to January) means are about +1.5°C and 1.4°C for NINO3 and NINO4, respectively.

An overview of the present climate in the tropical South Pacific Islands, with an outlook for the coming months, to assist in dissemination of climate information in the Pacific region.
Number 29 – 7 February 2003
January’s climate: The decaying El Niño continues to affect Southwest Pacific climate patterns with enhanced convection and above average rainfall over the equatorial regions of Kiribati and Tuvalu.

Climate developments in January 2003
El Niño related convection continues in the equatorial region
Suppressed convection in eastern Pacific, southeast from Papua New Guinea to New Caledonia
The SPCZ was close to its average position during January, extending southeast from Solomon Islands to Society Islands.

Rainfall outlook for February to April 2003
Above average or average rainfall in equatorial latitudes from west to east and the Solomon Islands trending southeast to Society Islands.
Below average or average rainfall from Vanuatu, Fiji, New Caledonia, trending east to the Marquesas Islands and Pitcairn Island.
Near average rainfall likely elsewhere.
Rainfall is expected to be above average in the equatorial Pacific from west to east due to continuing enhanced convection, resulting in above average rainfall in Western and Eastern Kiribati and the Solomon Islands.

Sources of South Pacific rainfall data
This bulletin is a multi-national project with important collaboration from the following Pacific nations:
American Samoa
Australia
Cook Islands
Fiji
French Polynesia
Kiribati
New Caledonia
New Zealand
Niue
Papua New Guinea
Pitcairn Island
Samoa
Solomon Islands
Tokelau
Tonga
Tuvalu
Vanuatu
Requests for Pacific island climate data should be directed to the Meteorological Services concerned.
Acknowledgements
This bulletin is made possible with financial support from the New Zealand Agency for International Development (NZAID), Wellington, New Zealand, wi