FXPQ50 PGUM 050738 AFDGUM Area Forecast Discussion National Weather Service Tiyan GU 538 PM ChST Thu Nov 5 2026 .Marianas Synopsis... Satellite and radar imagery show mostly isolated light showers across the Marianas this evening. Models and observations show combined seas of 6 to 7 feet. && .Discussion... A quiet pattern continues through Friday with little to no light showers. Friday night, scattered showers and isolated thunderstorms will be possible for Tinian and Saipan as Invest 99W tracks through the far northern CNMI, likely between Alamagan and Agrihan. Model guidance shows 99W slowly strengthening, possibly moving through the islands as a tropical depression or weak tropical storm. However, Guam and Rota will likely remain dry with light winds. Breezy conditions appear unlikely at this time for Tinian and Saipan, and would be limited to any thunderstorms. Afterwards, periods of isolated to low end scattered trade wind showers will likely return for the rest of the forecast period. && .Marine... Light to moderate trade winds are expected before becoming light Friday night and then returning Sunday. Combined seas of 6 to 7 ft will be steady most of the forecast period. Swells consist of an easterly trade wind swell and a small northwest swell. There will be a moderate risk of rip currents along north and east facing reefs through the weekend. Surf will be elevated along east-facing reefs, enhanced by approaching Invest 99W. As 99W passes through the far northern CNMI, it may bring scattered showers and isolated thunderstorms to the coastal waters of Tinian and Saipan around Friday night. Therefore, there will be a moderate risk of lightning Friday night near Tinian and Saipan as 99W passes by to the north. && .Tropical Systems... A weak disturbance, Invest 99W, is found well east of the Marianas, centered near 16N159E. 99W is moving slowly west-northwest, toward the northern CNMI. Latest guidance shows 99W moving through near Alamagan as a weak circulation, developing into a Tropical Depression to the west of the islands. However, latest satellite data does show a bit more organization with Invest 99W than was expected. Therefore, developing into a significant tropical cyclone before reaching the islands is a possibility. Invest 99W will be monitored closely over the next few days for any indications of faster development or change in movement. Residents of the northern CNMI should continue to monitor forecasts for any change in expected movement or intensity. For more information on Invest 99W, see bulletins issued by JTWC under WMO header ABPW10 PGTW. && .Eastern Micronesia... An overall dry pattern is in place across most of eastern Micronesia this evening. The only exception is Kosrae. Weak convergence associated with the Near-Equatorial Trough is generating low-end scattered showers and isolated thunderstorms that will continue at Kosrae through tonight, then dry out Friday morning. Otherwise, both Pohnpei and Kosrae can expect another weak increase in showers over the weekend, with a 30 percent chance of showers and a slight chance of thunderstorms Saturday night into Sunday. For Majuro, dry conditions are expected to continue through the beginning of next week. Benign marine conditions are expected to continue through the next several days, with seas of 3 to 5 feet at Pohnpei and Kosrae, and 4 to 6 feet for Majuro. Light to gentle winds will prevail across the region. && .Western Micronesia... The monsoon-like pattern remains disorganized and displaced to the south, with Palau, Yap, and Chuuk all in trade winds. This situation does not look to change through the entire forecast period, tonight through Tuesday. After Tuesday, getting toward mid-November, it looks like the monsoon pattern may start attempting arecovery for one more big push this year. Often the models are a bit precocious on this type of thing though, so it could easily bleed over into late November or even into December. Meanwhile, Chuuk, Yap, and Palau have primarily isolated showers through the forecast period. Palau has the most showers with scattered showers lasting from Sunday through Tuesday, but even here, QPF is expected to be less than impressive. The good news is, with winds at or below 15 knots, and seas at or below 5 feet, benign marine conditions will continue to rule the area. && .GUM WATCHES/WARNINGS/ADVISORIES... GU...None. MP...None. Marianas Waters...None. && $$ Marianas: Ogle East Micronesia/Tropical: Kleeschulte West Micronesia: Stanko