Area Forecast Discussion
Issued by NWS Tiyan, Guam
Issued by NWS Tiyan, Guam
186 FXPQ50 PGUM 020719 AFDGUM Area Forecast Discussion National Weather Service Tiyan GU 519 PM ChST Tue Jul 2 2024 .Marianas Synopsis... Satellite imagery is showing generally partly cloudy skies and isolated trade showers. Increased skies showers were present across the southern Guam waters and further south. Latest altimetry passes and Ritidian buoy data are indicating seas of 3 to 5 feet. && .Discussion... Expect mainly isolated trade showers through tonight. A disturbance approaching from the east will arrive tomorrow morning and looks to bring scattered showers through the 4th of July. Guam and Rota will likely see the greater coverage of showers, as moisture being pulled north from Micronesia will be deeper and convergent flow will be more pronounced. Isolated thunderstorms also expected through Thursday night, as instability increases and a TUTT cell aloft provides some upper-level support as it pushes overhead and west of the islands. For the rest of the forecast period, drier conditions expected with few upticks in showers and a slight chance of thunderstorms as disturbances push near to south of the Marianas, The best potential looks to be over the weekend as some models are hinting a disturbance drifting northwest out of Micronesia and possibly clipping the region. However, kept shower potential to slight this far out, as confidence is low due to lack of good model run-to-run consistency. && .Marine/Surf... Gentle to moderate trade winds and combined seas of 3 to 5 feet will continue this week. Some gusty winds and choppy seas are possible near heavier showers and thunderstorms, mainly over Guam and Rota waters, as a couple of disturbances pass near to south of the Marianas. A moderate risk of rip currents continues along east facing reefs, while low risk remains along all other reefs. Surf may rise around a foot on Wednesday night as the trade swell increases slightly. && .Eastern Micronesia... Much of the ITCZ has dissipated, but there is a trade-wind trough north and east of Kosrae expected to move west and bring showers to Pohnpei tonight and Wednesday, but for Kosrae expect only isolated showers through Wednesday. For Majuro, expect mostly cloudy with scattered showers tonight as clouds and showers develop upstream. Expect increasing clouds and showers approaching Majuro from the southeast over the next day or two. Region wide, shower potential is forecast to increase over the next few days through the weekend, most likely will see pockets of heavy showers around the time when the TUTT starts to dig south into the region Thursday and Friday. Altimetry observed seas of 3 to 4 feet around Kosrae`s waters. Little change in sea heights is expected. && .Western Micronesia... Ridging continues across Koror and Yap. Should see some showers for Yap later tonight with a weak trough moving into Yap`s waters. Models show on and off scattered showers starting around Wednesday evening for Koror with no real distinguishable features with winds remaining light through most of the week. Scattered showers at Chuuk are expected to wind down some time tonight becoming isolated by Wednesday night, then becoming on and off scattered showers around the weekend. Altimetry, Koror and Yap buoys are reporting 3 to 4 foot seas. Little change in sea heights is expected. && .GUM WATCHES/WARNINGS/ADVISORIES... GU...None. MP...None. Marianas Waters...None. && $$ Marianas: Slagle Micronesia: Hong