Pacific ENSO Update
3rd Quarter, 2007 Vol. 13 No. 3
Republic of Palau: During the first half of 2007, rainfall throughout Palau was slightly below normal. The 6-month total of 48.76 inches at the WSO Koror was 74% of normal, making this station one of only a few others (including stations on Guam and in the northern RMI) that received less than 75% of normal rainfall during the first 6 months of 2007. Other locations in Palau had more rainfall than at the WSO, and 6-month totals were roughly 85% of normal.
Republic of Palau State Rainfall Summary 2nd Quarter 2007
* Long term normal is not established for these sites
Climate Outlook: Easterly trade winds should continue to dominate the flow in eastern Micronesia (Pohnpei and eastward), and keep rainfall average to slightly below average there. Monsoon and storm activity will have more influence in western Micronesia (Chuuk and westward, including all islands of the Republic of Palau), where the rainfall should be average to slightly above average. The trade winds and sub-surface heating in the western North Pacific will keep sea levels above normal.
Tropical cyclone activity is expected to be below normal throughout the entire western North Pacific basin during 2007. Tropical cyclone activity should be near normal, however, in the western portion of the basin, meaning that Palau should experience two or three episodes of near-gale (25 to 35 mph) westerly winds and hazardous seas in island waters associated with tropical cyclones passing to the north. This level of risk is normal.
Surges in the southwest monsoon can also produce prolonged episodes of westerly wind on Palau, usually during the period from July through December. Rains associated with the monsoon trough and with tropical cyclones passing to north of Palau may yield a month or two with rainfall of 20 inches or more in any of the months during the period August through November. Because of this effect, some of the inclusive periods below have been given slightly above normal rainfall.
Forecast rainfall for Palau from August 2007 through July 2008 is as follows: