Three-month outlook
Three-month outlook: August to October 2007
Rainfall outlook map for September to November 2007. (Click for enlargement)
A La Niña-like pattern, with a large region of enhanced convection is expected from Vanuatu southeast to the Southern Cook Islands, with above average rainfall likely over Vanuatu, Wallis and Futuna, Tonga, Niue, and Fiji’s Rotuma Island.
Average or above average rainfall is expected in Papua New Guinea, the Solomon Islands, New Caledonia, Fiji, Samoa, the Southern Cook Islands, and Pitcairn Island.
Suppressed convection with below average rainfall is expected over Western and Eastern Kiribati, and Tuvalu.
Near or below average rainfall is likely in the Northern Cook Islands.
Near average rainfall is expected in Tokelau and French Polynesia.
Confidence in the forecast model skill, for this seasonal outlook, is moderate for most Pacific Island countries. In the past, the average region-wide hit rate for forecasts issued in September has been 60%.
| Island group | Rainfall outlook | Outlook confidence |
|---|---|---|
| Vanuatu | 20:35:45 (Above) | Moderate |
| Wallis and Futuna | 20:35:45 (Above) | Moderate |
| Tonga | 20:35:45 ((Above) | Moderate |
| Niue | 20:35:45 (Above) | Low |
| Papua New Guinea | 20:40:40 (Near or above) | Moderate |
| Solomon Islands | 20:40:40 (Near or above) | Moderate |
| New Caledonia | 25:35:40 (Near or above) | Moderate |
| Fiji | 20:40:40 (Near or above) | Moderate |
| Samoa | 20:40:40 (Near or above) | Moderate |
| Southern Cook Islands | 20:40:40 (Near or above) | Moderate |
| Pitcairn Island | 40:40:20 (Near or below) | Moderate |
| Tokelau | 20:45:35 (Near average) | Low |
| Society Islands | 20:50:30 (Near average) | Moderate |
| Tuamotu Islands | 25:45:30 (Near average) | Low |
| Austral Islands | 25:45:30 (Near average) | Moderate |
| Marquesas Islands | 30:45:25 (Near average) | Moderate |
| Northern Cook Islands | 40:40:20 (Near or below) | Moderate |
| Tuvalu | 45:30:25 (Below) | Moderate |
| Western Kiribati | 50:30:20 (Below) | High |
| Eastern Kiribati | 45:35:20 (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.