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The PEAC tropical cyclone outlook for the upcoming 2008 season is for more activity in the western North Pacific basin than occurred during 2007, even though the typhoon season may once again start get off to a late start because of La Niña conditions. Also, the geographical distribution of western North Pacific tropical cyclones should return to a more normal pattern, elevating the risk of a typhoon in Micronesia (from Chuuk and westward) to near normal. Islands from Pohnpei and eastward into the RMI experience tropical storms and typhoons primarily during El Niño. The risk of a damaging tropical cyclone in these locations is considered low during 2008 (but not quite so extraordinarily low as it was in 2007).

There has been some concern that above average SST in the vicinity of American Samoa would translate into an increased risk of a damaging tropical cyclone there. Through mid-January, however, the tropical cyclone activity has been focused westward and southwestward of the archipelago. At the time of this writing, an active phase of the Australian northwest monsoon was occurring in the Coral Sea, and Cyclone Funa had passed through Vanuatu with hurricane-force winds. This active phase of MJO will push out to the central South Pacific by the end of January, perhaps causing a tropical cyclone to form east of Niue and move through the Cook Islands. The PEAC Center remains cautiously optimistic that the primary focus of the South Pacific tropical cyclone activity for the next three months will remain in the Coral Sea from northeastern Australia eastward to Fiji (a view also supported by the TSR research group – see excerpt below). Through April of 2008, it is likely that one or two tropical cyclones will pass close enough to the south of American Samoa so as to bring gusty northwesterly winds of near-gale strength to the islands and territorial waters. The risk of a damaging impact by a hurricane or strong tropical storm in American Samoa is considered to be near normal (roughly a 5 to 10% chance) through April 2008. For comparison, the risk of a damaging impact by a typhoon on Guam is typically 10 to 20% during any given year, increasing to 25 to 30% during El Niño years.

On December 5, 2007, the Tropical Storm Risk Research Group issued the following assessment of tropical cyclone activity for the Australian region:

“ …. The TSR (Tropical Storm Risk) early December forecast update for Australian-region tropical cyclone activity in 2007/8 continues to anticipate activity 10-20% above the 1975/6-2006/7 climate norm. This would make the 2007/8 season the most active for basin tropical storms since 1998/9. The forecast spans the Australian season from the 1st November 2007 to the 30th April 2008 and is based on data available through the end of November 2007. Our main predictor is the actual anomaly in October-November Niño 4 sea surface temperatures (SST) which is below average at -0.95ºC. …

There is a 72% probability that Australian-region tropical storm numbers in 2007/8 will be above average (defined as more than 12 tropical storms), a 25% likelihood they will be near normal (defined as between 9 and 12 tropical storms) and only a 3% chance they will be below normal (defined as less than 9 tropical storms). …”

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The PEAC tropical cyclone forecasts for 2008 are provisional. Normally the PEAC Center considers input from two seasonal outlooks for tropical cyclone activity in the western North Pacific basin: (1) The City University of Hong Kong Laboratory for Atmospheric Research, under the direction of Dr. J. C-L. Chan, and (2) The Benfield Hazard Research Centre, University College London, Tropical Storm Risk (TSR) research group, UK, led by Dr Adam Lea and Professor Mark Saunders. These agencies have yet to release an assessment of typhoon activity for 2008.