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Tropical Weather Discussion...CORRECTED
National Weather Service Tiyan GU
926 AM ChST Fri Jul 26 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...

TROPICAL CYCLONES...
Tropical Storm Gaemi and its affects have moved away from our
region and onshore into southeast China. Meanwhile, a weak
circulation just south of Koror near 6N134E has been labeled
as Invest 95W. Large areas of showers and isolated thunderstorm
with gusty winds are seen over most of Palau and Yap State. Invest
95W is expected to move slowly toward the northwest and gradually
develop as it moves into and through the Philippine Sea.

MONSOON TROUGH AND TROPICAL DISTURBANCES...
The monsoon trough extends eastward from 95W at 6N134E to just
north of Weno Chuuk at 9N151E. North of this trough axis, where
southeast to east surface winds are converging, we see scattered
to numerous showers and very isolated thunderstorms northward to
about 13N. These showers will affect Guam and Rota at times the
next couple of days. South of the axis, surface winds are west to
southwest at 10-20 mph with some heavier showers moving briskly
at 25-35 mph. Numerous showers are seen over western and northern
Chuuk State, besides over Yap and Palau.

The monsoon trough will begin to lift WNW the next several days
with good potential of the circulation becoming better organized
as it passes toward the NW of Yap and Palau. As it does this,
gusty SW winds and periods of heavy showers will continue over the
region before pulling away over the weekend to the NW.

...OTHER WEATHER SYSTEMS...

TRADE-WIND TROUGHS...
A surface trough is moving slowly over the Mariana Islands today,
and divergent upper-level winds will continue over the region.
Isolated to scattered showers are seen over most of the Marianas.
Heavier showers could produce wind gusts of 25 to 30 mph. This
relatively wet synoptic scale pattern over the Marianas will
persist the next couple of days at least.

A westward-moving trough north of Chuuk is centered near 11N152E.
Showers and thunderstorms are seen between 9N and 13N from 152E
to 157E.

Another surface trough moving from Kosrae toward Pohnpei is also
causing showers and very isolated thunderstorms, mainly from the
northwest of Kosrae to southeast of Kosrae.

TUTT...
The TUTT runs westward from 22N180 through two upper-level lows,
NW of Wake Island at 23N163E and NE of the Marianas at 20N151E,
then southwestward ending near 12N140E. Strong southwest to west
winds aloft south of the TUTT are triggering showers and isolated
thunderstorms in two relatively small areas, one just northeast
of Wake centered at 20N169E and one farther northwest of Wake at
21N160E.

The TUTT is very slow moving and more transitional in nature, but
could eventually lift northward over the weekend with westerly
winds aloft slowly decreasing.

...ITCZ...
The ITCZ remains active over eastern Micronesia, mainly between
3N and 6N from 160E to beyond the Date Line. A surface trough and
heavy showers are also embedded in the ITCZ just moving across
the Date Line. Areas of heavy showers and a few thunderstorms are
seen from near Majuro to Tarawa, and generally between 1N and 7N
from 170E eastward to beyond 180.

$$

Simpson