![National Oceanic and Atmospheric Administration](/build/images/header/noaa.d87e0251.png)
![National Weather Service](/build/images/header/nws.4e6585d8.png)
![United States Department of Commerce](/build/images/header/doc.b38ba91a.png)
Tropical Weather Discussion
Issued by NWS
Issued by NWS
046 AXPQ20 PGUM 140046 TWDPQ Tropical Weather Discussion National Weather Service Tiyan GU 1046 AM ChST Fri Jun 14 2024 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... None. ...OTHER WEATHER SYSTEMS... TROUGHS... A surface trough extends from across the Philippines and enters western Micronesia around 9N130E and continues towards Palau and Yap Proper, before merging with the weak trade-wind flow and trade-wind troughs that have broken off from the ITCZ in eastern Micronesia and near Chuuk. The surface trough is similar to a weak monsoon trough and is an early indication of a transition to the monsoonal pattern that occurs during the summer. Light to gentle southwest winds extend along the southern edge of the surface trough. Scattered showers extend from Palau and northeast to Yap State and finally south of Guam. The surface trough looks to linger in far western Micronesia for at least the next couple of days as winds remain on the lighter side as Palau and Yap remain in this early transitional phase. TUTT... The primary upper-level low is now located near 17N149E as it continues to drift westward towards the northern islands of the Mariana Islands, and will likely pass near and then west of Pagan and Alamagan within the next 24 hours. Convection remains limited near the center of the low, but the Global Lightning Detection (GLD) network shows isolated thunderstorms south of the low and east of Saipan and Tinian. Most of the showers and thunderstorms are found farther to the southeast along and south of the TUTT axis that curves southwest from across the Date Line at 17N180 to 11N170E and then slowly curving northwest to the TUTT low. Part of this TUTT axis is near the ITCZ discussed in more detail below. Another trough extends southwest from the low passing south of Guam and ending in Yap State near 9N143E, helping to enhance convection between Guam and Yap Proper. The TUTT low will continue westward and move through and then west of the Marianas, and will likely pass near and then west of Pagan and Alamagan within the next 24 hours. Its presence will help to bring showers and thunderstorms to the Marianas through Saturday, with the potential for showers and thunderstorms decreasing Sunday as the TUTT moves away from the Marianas. OTHER SYSTEMS... ...ITCZ... The ITCZ still extends across eastern Micronesia, but has shifted slightly northward as the bulk of the convergence between the northeast and southeast trade winds is between 6N and 8N as it extends from the Marshall Islands to Pohnpei and then becoming much less defined near Chuuk. Scattered to numerous showers and isolated thunderstorms are developing along or just north of the trade convergence due to the upper-level support from the TUTT discussed above. The ITCZ will continue to affect the region over the next couple of days with some minor shifts to the north and south as models show the ITCZ fragmenting by early next week, but still supporting scattered showers across the region. $$ Schank