Area Forecast Discussion
Issued by NWS Tiyan, Guam
Issued by NWS Tiyan, Guam
855 FXPQ50 PGUM 082008 AFDGUM Area Forecast Discussion National Weather Service Tiyan GU 608 AM ChST Thu May 9 2024 .Marianas Synopsis... Satellite imagery is showing partly to mostly cloudy skies with isolated showers. Latest altimetry data is indicating seas of 4 to 6 feet in the coastal waters. Winds are gentle to moderate. && .Discussion... A weak trade-wind trough is passing through the region today and may see an uptick in showers today, as CIMMS MIMIC Precipitable Water product is showing values in the 2"+ range, but shower coverage should generally remain isolated. By later today, the dry trade-wind pattern returns with only slight upticks in clouds and showers expected with passing wrinkles in the trades. && .Marine/Surf... Gentle to moderate winds and combined seas in the 4 to 6 foot range are expected through the weekend. As the north to northeast swell diminishes, the east trade-wind swell is expected to build through the weekend. A moderate risk of rip currents will continue along east facing reefs for the next several days. The moderate risk of rip currents along north facing reefs expected to become low by Friday morning. && .Tropical Systems... A Near-Equatorial Trough (NET) is evident on the latest ASCAT analysis to the south of Yap and Palau. Within the NET, this is an area of interest being monitored by the Joint Typhoon Warning Center (JTWC) Invest 92W is a sub low and is centered near 3N147.9E. Latest model guidance shows 92W drifting off to the west-northwest over the next several days and very slowly organizing, though it looks unlikely that 92W will develop into a significant Tropical Cyclone (TC) before passing through Palau early next week. Residents of Palau and western Yap State should continue to monitor forecasts over the next few days for any possible change in the expectations for Invest 92W. && .Eastern Micronesia... No major changes to the forecast. The trade-wind convergence continues to move across the region with surface troughs within the trade-wind convergence bringing scattered showers and isolated thunderstorms for Pohnpei and Kosrae the next few days. Did reduce POPs for Pohnpei today, as models and satellite show showers early morning then some clearing after trough passage. For Majuro, scattered showers are expected to be low-end, with a possible increase in shower potential around the weekend. Altimetry shows around 5 to 7 feet across the islands` coastal waters. Expect a decrease in combined sea heights of about 1 to 2 ft over the weekend. && .Western Micronesia... Convective activity is developing east of 140E, along and north of the near equatorial trough, and convective activity continues further east near 4N146E with Invest 92W. Expect to see scattered showers near Yap today. Satellite indicated spotty showers developing near Yap`s waters, so bumped up the timing of scattered showers for Yap to today. Models continue to track Invest 92W west to pass south of Koror late weekend or so, possibly increasing showers, winds and seas for Koror and Yap. Scattered showers for Chuuk today, then winding down through the evening and Friday. Gentle to moderate trades and combined seas of 3 to 5 feet are expected across the region through the weekend. && .GUM WATCHES/WARNINGS/ADVISORIES... GU...None. MP...None. Marianas Waters...None. && $$ Marianas: Slagle Tropical: Slagle Micronesia: Hong