Tropical rainfall outlook: November 2007 to January 2008
A La Niña-like pattern continues, producing a large area of suppressed convection along the equator from Western Kiribati to Eastern Kiribati, including Tuvalu. Below average rainfall is also likely in Tokelau,the Northern Cook Islands, and the Marquesas.
Enhanced convection is likely along a SPCZ displaced southwest of its normal position, from Papua New Guinea to Tonga, then the Society and Austral Islands of French Polynesia. Included in the above average rainfall are NewCaledonia, Vanuatu, Fiji, Tonga, Niue, Southern Cook Islands, and Pitcairn Island.
Near of above average rainfall is expected in Papua-NewGuinea, the Solomon Islands and Samoa.
Near average rainfall is expected in the Tuamotu Islands.
The confidence in the forecast model skill for this seasonal outlook is moderate to high for most Pacific Island countries. In the past, the average region-wide hit rate for forecasts issued in November has been 64%, 4% higher than the long-term average for all months combined.
| Island group | Rainfall outlook | Outlook confidence |
|---|---|---|
| Tonga | 15:30:55 (Above) | High |
| Niue | 20:30:50 (Above) | High |
| Fiji | 20:35:45 (Above) | High |
| Vanuatu | 25:30:45 (Above) | Moderate |
| New Caledonia | 20:35:45 (Above) | Moderate-high |
| Wallis & Futuna | 25:30:45 (Above) | Moderate |
| Southern Cook Islands | 20:35:45 (Above) | Moderate |
| Austral Islands | 20:35:45 (Above) | Moderate-high |
| Society Islands | 20:35:45 (Above) | Moderate |
| Pitcairn Islands | 20:35:45 (Above) | Moderate |
| Papua New Guinea | 20:40:40 (Near or above) | Moderate |
| Solomon Islands | 20:40:40 (Near or above) | Moderate |
| Samoa | 20:40:40 (Near or above) | Moderate |
| Tuamotu Islands | 30:45:25 (Average) | Moderate |
| Tokelau | 40:35:25 (Below) | Moderate |
| Marquesas | 45:30:25 (Below) | Moderate |
| Northern Cook Islands | 40:35:25 (Below) | Moderate |
| Tuvalu | 50:30:20 (Below) | High |
| Western Kiribati | 60:25:15 (Below) | High |
| Eastern Kiribati | 50:30:20 (Below) | High |
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.