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AXPQ20 PGUM 060057 CCA
TWDPQ

Tropical Weather Discussion...CORRECTED
National Weather Service Tiyan GU
1057 AM ChST Wed Aug 6 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...

TRADE-WIND TROUGHS...
A trough in the trades stretches from 5N140E to west of Saipan.
Fairly widespread convection will continue to accompany this
feature, due to strong surface convergence, as it heads west the
next few days.

Farther east-southeast, a subtle trough stretches from just
northeast of Kapingamarangi through Pohnpei to west of Ujelang.
Convection is widespread south-southwest of Pohnpei due to
stronger surface convergence, with another pocket of activity
north-northeast of Pohnpei. All of this activity will continue
westward over the next few days with pockets of convection
stretching along the trough axis.

Then, a third and final surface trough stretches from southeast of
Kosrae through Majuro to the northeast, ending near 13N177E. Here
too, the best coverage and intensity of convection is located
along the southern portions of the trough axis, east and southeast
of Kosrae. This is due to better moisture quality and depth as
PWATs are in excess of 2.25 inches. Further northeast, lower PWATs
are resulting in isolated convection until you pass 10N, where
better convergence and PWATs near 2.5 inches, locally higher, are
producing numerous showers and thunderstorms. This feature will
maintain orientation as it heads west the next several days with
convection along it.

TUTT...
A TUTT axis stretches 23N180 through a col northeast of Wake Island
to a TUTT cell over Chuuk, then stretches to another smaller TUTT
cell northwest of Saipan, crossing 23N130E to a fourth TUTT cell
southeast of Taiwan. Aside from convection around the periphery of
these cells, the main effect they have is to provide divergence aloft
for any surface troughs in the trades, as mentioned above. In
general, the models show the TUTT orientation changing over the next
few days. That said, today`s pattern is more complicated than what
the models showed yesterday, so it`s hard to say what the orientation
of it (the TUTT) will be by the weekend when the pattern change
stabilizes.

$$

Doll