Area Forecast Discussion
Issued by NWS Tiyan, Guam
Issued by NWS Tiyan, Guam
663 FXPQ50 PGUM 252008 AFDGUM Area Forecast Discussion National Weather Service Tiyan GU 608 AM ChST Sun May 26 2024 .Marianas Synopsis... ASCAT Analysis indicates a weak surface trough is just moving into the far northern Mariana Islands. Satellite shows patchy clouds near and northeast of Saipan, and patchy clouds were also just west of Guam. Local airports report gentle trade winds, and combined seas are running 4 to 6 feet. && .Discussion... In the near term; the surface trough over the far northern CNMI could trigger a few showers for Saipan and Tinian today, and there could be light showers farther south. Also, models are hinting that another trough could move across the Marianas by about Tuesday and trigger a few showers. Otherwise pleasant and fair weather is expected for the region. && .Marine... Benign marine and surf conditions with a slightly elevated trade swell are expected to continue. A background north to northwest swell coming from distant storms far north may pass thru coastal waters later this week. A moderate risk of rip currents continues along east facing reefs, with a low risk south, west and north reefs. && .Fire weather... Rainfall yesterday at Guam airport was 0.01 inch and the KBDI is just up to only 446 for today. Heavy rainfall two days ago was widespread and isolated light showers are expected at times in the coming week. For the near term; the risk of fast spreading wildfires is low. && .Eastern Micronesia... Scattered showers and isolated thunderstorms are ongoing east of Majuro north of the Inter-Tropical Convergence Zone. Scattered showers and a few thunderstorms were seen overnight north of Pohnpei along a trade-wind trough pushing over the island. Models guidance continues to show the ITCZ building westward south of Majuro through Kosrae and into Pohnpei through early next week keeping a wet and active pattern with the peak of shower and thunderstorm activity expected sometime Monday into Tuesday. For the rest of the week, the ITCZ is expected to become fragmented with convergence and trade-wind troughs bringing periods of isolated to scattered showers and isolated thunderstorms expected through the end of the work week. Gentle to moderate trades and benign sea conditions are expected to persist through the latter part of this week. Altimetry shows combined seas are between 4 to 6 feet in the Marshalls and 5 to 6 feet at Kosrae and Pohnpei. && .Western Micronesia... Convergent flow over Palau continues to bring scattered showers and isolated thunderstorms this morning. The convergent flow will further diminish today with scattered showers and isolated thunderstorms at Palau becoming isolated as TS 01W, currently over the Philippines, continues to move north and away from the region. An active trade- wind pattern is expected to develop early next week for Yap and Palau with scattered showers and isolated thunderstorms. For Chuuk, a broad trough between Pohnpei and Chuuk will bring scattered showers and isolated thunderstorm to Weno today. Latest model guidance continues showing the ITCZ building westward later today into early next week before fragmenting into a series of trade- wind troughs. For the rest of next week, an active trade-wind pattern with embedded troughs in the flow will bring periods of showers and thunderstorms over Weno. Gentle to moderate winds and sea conditions are expected to persist through the latter part of this week. Altimetry shows combined seas are mainly 4 to 5 feet this morning. && .GUM WATCHES/WARNINGS/ADVISORIES... GU...None. MP...None. Marianas Waters...None. && $$ Marianas: Simpson Micronesia: Kelly