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TWDPQ

Tropical Weather Discussion...UPDATED
National Weather Service Tiyan GU
1140 PM ChST Sat Oct 19 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...

.UPDATED FOR TROPICAL CYCLONE FORMATION ALERT...

TROPICAL AND MONSOON DISTURBANCES...
A Tropical Cyclone Formation Alert has been issued for Invest 96W,
which replaced Invest 94W. Invest 96W is currently
located near 14.1N and 138.1E, about 443 Statute Miles west of
Guam. Deep convection with numerous showers and thunderstorms are
seen southwest and northeast of the center. Latest guidance
indicates that TCFA 96W will drift slowly west and strengthen over
the next several days, but models vary greatly on strength and
location. Invest 96W is not expected to directly impact the
Marianas, Yap or Palau, but a monsoon type wind flow will cause
inclement weather across these areas.

Another monsoon disturbance, Invest 95W, is centered just south
of Guam near 12.5N 144.5E. 95W is showing as a broad circulation
with an ill-defined center at this time. A broad area of moderate
to deep convection is seen west of the Marianas to north of Chuuk,
as far north as 19N. Models vary greatly on the movement and
development of 95W over the next few days, so confidence in the
development and location of 95W over the next few days is very
low. The probability of 95W becoming a significant tropical
cyclone over the next 24 hours is low.

For more information on Invest 96W and Invest 95W, see bulletins
issued by the Joint Typhoon Warning Center under WMO header ABPW10
PGTW.

...OTHER WEATHER SYSTEMS...

MONSOON TROUGH...
The monsoon trough extends east-northeast from near Mindanao across
130E near 13N into Invest 94W. It continues east through Invest 95W
to end north of Weno, Chuuk near 13N151E. Moderate to deep convection
with scattered to numerous showers and isolated thunderstorms are
found over a large area near and north of the trough, and and with
Invests 94W and 95W, across the Marianas to north of Chuuk, north of
11N. In the monsoon flow south of the trough, moderate to deep
convection crosses into Palau to south of Yap Proper. As the MJO
continues to affect the region, the monsoon trough is expected to
strengthen over the next few days with little change in location.
This is expected to bring increasing convection across Palau and Yap
over the next couple of days along with increasing southwest to west
winds. Gale-force winds are a possibility early next week.

TRADE-WIND TROUGHS...
A weak trade-wind trough is found over Majuro, stretching northward
from near 6N172E to 14N172E. Scattered moderate to deep convection is
associated with trough over and north of Majuro. The trough will
continue to move west-southwest over the coming days.

Another trade-wind trough is seen southwest of Pohnpei from 3N155E to
8N154E. Scattered moderate to deep convection is seen with this
trough southwest of Pohnpei to the equator. The trough will slowly
move west the northwest as it erodes the weak surface ridge currently
over Chuuk.

OTHER SYSTEMS...
A band of strong convergence is seen over Chuuk State, south of the
eastern end of the monsoon trough, where moderate to fresh southwest
to west winds are converging into east to south winds east trade
winds with a weak surface ridge over the area.

A band of upper-level divergence west of an upper-level trough is
generating a broad area of moderate to deep convection between
Kwajalein and Wake Island. The trough and associated divergence look
to continue moving east over the coming days with decreasing
convection as the divergence weakens.

A surface trough extends northwestward from Invest 94W, producing
scattered deep convection in a narrow line to beyond 130E at 18N.

$$

Kleeschulte/Simpson/Williams