Area Forecast Discussion
Issued by NWS Tiyan, Guam
Issued by NWS Tiyan, Guam
438 FXPQ50 PGUM 290729 AFDGUM Area Forecast Discussion National Weather Service Tiyan GU 529 PM ChST Sat Jun 29 2024 .Marianas Synopsis... Gentle to moderate trades prevail in the region. Satellite imagery indicates a few lines of showers crossing Rota and Tinian waters. Ritidian buoy shows that seas are around 5 feet. && .Discussion... Satellite MIMIC TPW indicates that PWAT values upstream are expected to dip below 2 inches, which in addition to the upper-level low northwest of the region moving further away, makes thunderstorms less likely to develop over the Marianas over the next few days. Even so, disturbances moving across Micronesia are still expected to trip over Guam occasionally, bringing low-end scattered showers tonight through Sunday, as well as potentially sometime around midweek. Meanwhile, the Northern Marianas should see a much more pleasant weather regime for much of the forecast period. && .Marine... Combined seas of 4 to 6 feet will drop to 3 to 5 feet by Monday, staying as such for the rest of the week. A moderate risk of rip currents is expected along east facing reefs through at least the middle of next week, with a low risk expected along all other reefs. && .Eastern Micronesia and Chuuk... An ITCZ pattern is developing and taking hold across the region. Expect active weather through the weekend into next week, with scattered to numerous showers and isolated thunderstorms. Heavy downpours and gusty winds possible with stronger showers and thunderstorms, especially through early next week, with passing trade-wind troughs and a Tropical Upper Tropospheric Trough (TUTT) to the north providing upper-level support. A robust trough currently working through the Marshall Islands and pushing into Kosrae will work into Pohnpei Sunday and Chuuk Sunday night. Winds will generally be light to gentle around Chuuk and light to moderate across eastern Micronesia for the period. Fresh to strong gusts possible for Kosrae through Sunday and Pohnpei Sunday and Sunday night. Combined seas of 3 to 5 feet for most of the region and up to 6 feet at Majuro. && .Western Micronesia for Palau and Yap... A tropical disturbance is centered near 6N129E to the southwest of Palau and continues to slowly drift northwest towards the Philippines through the weekend. A trough extending northeast from the disturbance across the main islands of Palau and Yap Proper will slowly drift northwest, with convergent southerly winds bringing scattered to numerous showers and isolated thunderstorms through the weekend. Heavy downpours and gusty winds possible tonight for Yap and through Sunday for Palau. For next week, quieter weather expected as a weak wind pattern sets up with some subtle disturbances passing through and bringing scattered showers at times. Island-effect convection could also flare up at times next week under the weak wind regime. Wind mostly gentle this weekend look to become light to gentle for Yap and light for Palau for most of next week. Fresh to strong gusts possible with heavier showers tonight for Yap and through Sunday for Palau. Combined seas of 3 to 5 feet look to drop a foot or two by early next week, as various swells and wind waves decrease. && .GUM WATCHES/WARNINGS/ADVISORIES... GU...None. MP...None. Marianas Waters...None. && $$ Marianas: Montvila Micronesia: Slagle