515 AXPQ20 PGUM 140054 TWDPQ Tropical Weather Discussion National Weather Service Tiyan GU 1054 AM ChST Tue Apr 14 2026 Tropical Weather Discussion for the Western North Pacific between the Equator and 25N from 130E to 180. The following information is based on recent satellite imagery/data, weather observations, radar, and meteorological analysis. ...SPECIAL FEATURES... TROPICAL CYCLONES... As of the 1000 AM ChST PGUA radar fix, Super Typhoon Sinlaku was centered near 14.3N 146.6E, or about 135 miles east-northeast of Guam radar, 80 miles southeast of Tinian and Saipan. The latest 3-hourly track indicates a slight northward shift in Sinlaku's path, and a slight increase in forward speed, moving north- northwest at 9 mph toward Tinian and Saipan. Additionally, radar reflectivity depicts the appearance of a secondary eye wall with a roughly 50-mile diameter, with the inner eye still around 10 to 15 miles in diameter. Bands of heavier showers continue to move south to southeastward over the Marianas with Saipan seeing gusts up to near 85 mph, and Guam seeing gusts to around 75 mph this morning. As Sinlaku moves closer to the islands, winds will continue to increase, with rapidly worsening conditions for Tinian and Saipan. The highest reflectivities and heaviest showers are currently seen in the outer rain bands south of Guam and just east-southeast of Saipan and Tinian, along the inner periphery of the secondary eyewall. The latest forecast track from the Joint Typhoon Warning Center (JTWC) maintains a north-northwest passage of Sinlaku over or near Saipan and Tinian late tonight, potentially passing north of both islands if the current track holds. Sinlaku's track looks to shift more northward after it crosses the Marianas, moving through the northern CNMI just west of the islands on Wednesday through Thursday night, before making a northeast turn away by the end of the week. Super Typhoon Sinlaku is on a gradual weakening trend through the next few days, but is still expected to cross the Marianas as a Category 4 storm. For more information please refer to bulletins from the Joint Typhoon Warning Center under WMO header WTPN31 PGTW and from the National Weather Service under WMO header WTPQ31 PGUM. ...OTHER WEATHER SYSTEMS... SURFACE TROUGHS... A broad, weak surface trough extends southwest from Super Typhoon Sinlaku, passing near Yap Proper, just north of Koror, then extends west-northwestward through 9N130E. Patchy scattered showers are seen within the trough axis west-northwest of Palau. Some of the far outer rainbands of STY Sinlaku extend just north of Yap Proper, just north of the trough axis. Another trough extends southeast from Sinlaku, passing over Weno, Chuuk, then south of Pohnpei, to around EQ163E, with scattered showers seen south of Pohnpei. These weak features will shift very slowly northward with the movement of Sinlaku, helping to maintain patchy showers across the general area near and south of Pohnpei and Chuuk through the latter half of the week. TRADE-WIND SURGE... A large trade-wind surge continues north of Super Typhoon Sinlaku to around 22N, from around 145E to 165E, within the strong pressure gradient between Sinlaku and high pressure well to the north and northeast. Aside from the outer rain bands of STY Sinlaku and the trailing convergence to its east, patchy scattered showers and cloud cover are seen within the trade-wind surge to the north of these features. The easterly trade winds will weaken east towards the Date Line over the next few days as STY shifts northwestward, and high pressure to the northeast moves further away. OTHER SYSTEMS... A Westerly Wind Burst (WWB) is located along the equator to southern Pohnpei State. Fresh to strong winds encompass much of eastern Yap State and western Chuuk State, strengthening to near-gale force in northwestern Chuuk State. As Sinlaku curves northwest to north over the next couple days, fresh to near-gale force westerlies will begin to subside to moderate to fresh across eastern Yap State and western and northwestern Chuuk. ...ITCZ... An Intertropical Convergence Zone (ITCZ) fragment extends westward across the Date Line near 7N, then curving northwestward across Majuro and the northern Marshalls. Over the next few days, this pattern shifts out of the cross-equatorial flow, blending into the overall trade-wind convergence in the wake of STY Sinlaku, also shifting northward as Sinlaku moves across the far northern Marianas. $$ Cruz/DeCou