Three-month outlook

Three-month outlook: July to September 2007
 
Rainfall outlook map for July to September 2007.

Three-month outlook: July to September 2007

 

Rainfall outlook map for July to September 2007. (Click for enlargement)

The rainfall forecast for the Pacific region for the coming three months depicts La Niña like pattern.

Enhanced convection is expected over Samoa and the Northern Cook Islands where rainfall is expected to be above aveage.

A large region of near or above average rainfall is likely from Papua New Guinea to French Polynesia, including the Solomon Islands, Vanuatu, Walli and Futuna, Fiji, Tonga, Niue, the Southern Cook Islands, Tuamotu Islands, Society Islands, and the Austral Islands.

Suppressed convection is likely in the equatorial region of Western and Eastern Kiribati, where rainfall is forecast to be below average. Near or below average rainfall is expected over Tuvalu and Tokelau.

The rainfall forecast model skill is around moderate for this time of the year.

Island group Rainfall outlook Outlook confidence
Samoa 30:30:40 (Above) Moderate
Northern Cook Islands 30:25:45 (Above) Moderate
Papua New Guinea 20:40:40 (Near or above average) Moderate
Solomon Islands 20:40:40 (Near or above average) Moderate
Vanuatu 20:40:40 (Near or above average) Moderate
Wallis and Futuna 20:40:40 (Near or above average) Moderate
Fiji 20:40:40 (Near or above average) Moderate
Tonga 20:40:40 (Near or above average) Moderate
Niue 20:40:40 (Near or above average) Moderate
Southern Cook Islands 20:40:40 (Near or above average) Moderate
Tuamotu Islands 20:40:40 (Near or above average) Moderate
Society Islands 20:40:40 (Near or above average) Moderate
Austral Islands 20:40:40 (Near or above average)) Moderate
New Caledonia 25:40:35 (Near average) Low – moderate
Marquesas Islands 20:45:35 (Near average) Moderate
Pitcairn Island 30:40:30 (Near average) Moderate
Tuvalu 40:40:20 (Near or below average) Moderate
Tokelau 40:40:20 (Near or below average) Moderate
Western Kiribati 40:30:30 (Below) Moderate
Eastern Kiribati 40:30:30 (Below) Moderate

NOTE: Rainfall estimates for Pacific Islands for the next three months are given in the table. The tercile probabilities (e.g., 20:30:50) are derived from the interpretation of several global climate models. They correspond to the odds of the observed rainfall being in the lowest (driest) one third of the rainfall distribution, the middle one third, or the highest (wettest) one third of the distribution. On the long-term average, rainfall is equally likely (33% chance) in any tercile.