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785 FXPQ50 PGUM 052022 AFDGUM Area Forecast Discussion National Weather Service Tiyan GU 622 AM ChST Wed May 6 2020 .Marianas Synopsis... Satellite shows partly cloudy skies, moderate trade winds and a few light showers across the Marianas. A batch of showers is grazing the far southern waters of Guam. Seas are 4 to 6 feet from the east. && .Discussion... Only a few cosmetic changes to the previous forecast. Guidance and satellite imagery depict a dry and rather featureless trade-wind pattern east of the Marianas. Therefore, expect partly cloudy skies and only isolated light showers the next several days. A couple of trade-wind disturbances will slide near or south of Guam early next week. GFS model continues to bounce back and forth with the northward extent of shower across the Marianas while ECMWF maintains patchy showers south of Guam. Some of this model variability appears to be related to (1) a broad/weak disturbance that will meander near Yap and Palau the next several days and (2) the position and intensity of an upper-level low that is forecast to develop west of the Marianas late this week. Maintained mostly cloudy skies and isolated showers for Sunday and Monday as it remains the most reasonable outcome at this time. && .Marine... Latest ASCAT, buoy data and model guidance indicate trade winds have eased a bit over and upstream of the Marianas. Combined seas should fall 1 to 2 feet tonight through Friday before rising back to between 5 and 6 feet this weekend. Trade-wind swell will maintain a moderate rip risk along east facing reefs through the week. && .Fire weather... A trade-wind disturbance brought wetting rain to southern Guam yesterday but dry weather is expected the next few days and fuels will dry out. Winds look to stay at moderate levels the next few days so a fire weather watch is not expected. The KBDI is in the high category at 575. && .Eastern Micronesia... Satellite shows a broken band of trade-wind convergence stretching across eastern Micronesia from south of Pohnpei across Kosrae to south of Majuro. The models are persistent with this convergence zone over the next few days, drifting it slowly north through Sunday. Scattered showers and isolated thunderstorms will persist around Kosrae today through Friday, tapering to isolated over the weekend as the convergence moves north of the island. But that northward drift will bring scattered showers and isolated thunderstorms to Pohnpei Thursday through Friday, and to Majuro Thursday through Saturday. On Sunday, scattered showers return to Pohnpei as convergence expands back down from the north. Seas will generally be a little elevated at 6 to 8 feet for all three locations, but that will be enough to keep high surf going through tonight along east facing reefs of Kosrae. && .Western Micronesia... In the west, a broad but weak circulation, now carried as Invest 95W by JTWC, is centered well south of Yap near 4N140W. The models show little more than a quasi-steady state over the next few days for 95W, with no development, and a slow WNW drift for the center. Satellite currently shows deep convection southeast through east of Palau and Yap. Scattered showers and isolated thunderstorms are expected for Yap today, tapering off to isolated tonight through Saturday, then increasing to scattered again Sunday, but details on the timing of scattered are highly uncertain as long as 95W remains so loosely organized. At Koror, scattered showers should hold off until tonight and Thursday before going isolated for Thursday night and Friday. Scattered showers return there for the weekend as 95W drifts by just to the south. But again, details are uncertain, and we will have to track developments from day to day. Chuuk lies outside the influence of 95W, but the western end of the convergence zone to the east will be lurking to the south, and it should finally bring scattered showers and isolated thunderstorms over the weekend as the zone drifts north. For all three locations, seas will be moderate 4 to 6 feet, with no high surf expected. && .GUM WATCHES/WARNINGS/ADVISORIES... GU...None. Marianas Waters...None. && $$ Bukunt/Middlebrooke