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TWDPQ 



Tropical Weather Discussion

National Weather Service Tiyan GU

1059 AM ChST Thu May 8 2025



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...



NEAR EQUATORIAL TROUGH...

A Near-Equatorial Trough (NET) enters the region near 2N130E,

extending east-southeast across western Micronesia to a buffer 

circulation near 1N141E, to then extend further east and end near

EQ155E near Kapingamarangi. Moderate convection is associated with

this feature, producing scattered to numerous showers south of the

trough axis to the Equator, and some showers and thunderstorms in a

cluster northward from the aforementioned buffer and Yap Proper. 

This feature will remain in the general vicinity through the weekend,

with little change in convective activity other than in the 

northeastern peripheries interacting with a convergence zone upstream

by early next week.



CONVERGENCE ZONE...

A convergence zone spans much of eastern Micronesia, extending

eastward from a broad surface trough across much of Pohnpei State,

Kosrae State and the Marshalls to end at the Date Line. Moderate to

deep convection is associated with this feature, producing numerous

showers and some thunderstorms over Pohnpei, Kosrae, and the southern

Marshalls. This feature is expected to weaken in convective activity

overnight, followed by another pulse sometime during the weekend,

before breaking down into an average trade-wind regime early next

week.



TRADE-WIND TROUGHS...

Multiple trade-wind troughs are observed across the region, with most

concentrated mainly within the aforementioned convergence zone. The

exception being a broad surface trough extending from the easternmost

edge of the NET northward across Kapingamarangi, curving northwest to

end near Chuuk. Moderate convection is associated with this feature,

producing scattered showers across the southern half of Chuuk and

Pohnpei States in central Micronesia, and some pockets of

thunderstorms just northeast of Chuuk. This trough is expected to 

follow the movement of the buffer circulation near the Equator, 

before dissipating sometime early next week.



TUTT...

A Tropical Upper-Tropospheric Trough (TUTT) enters the region near

25N175E, extending southwest to a significant TUTT low centered near

20N162E west-northwest of Wake Island, to then extend further 

southwest into Micronesia to end east of Yap Proper. Moderate 

convection is associated with this feature as it interacts with 

surface features, producing numerous to widespread thunderstorms 

within the general vicinity of the TUTT low from 159E to 165E between

22N and 16N. The TUTT low will begin to weaken later this afternoon,

as it is being absorbed by the much more significant TUTT low to the

northeast along the trough axis, followed by the evaporation of the 

entire trough as the second TUTT low shifts the flow east by the 

weekend.



OTHER SYSTEMS...

A dissipating semi-stationary front enters the region near 25N142E

over Iwo To, extending westward to then exit the region near 23N130E.

Some thunderstorms and widespread cloudiness are observed within 175

miles of the frontal axis. This feature is expected to disintegrate

quickly overnight, as a high pressure cells exits the eastern shores

of Tohoku and separates the frontal system from another low in

eastern China.



$$



Montvila