271
FXPQ50 PGUM 072059
AFDGUM

Area Forecast Discussion
National Weather Service Tiyan GU
659 AM ChST Sat Jun 8 2024

.Marianas Synopsis...
Partly sunny skies with scattered showers will move through the Guam
and Rota waters today, while partly cloudy skies with isolated
showers will move through the Tinian and Saipan waters today.
Combined seas of 4 to 6 feet are composed mainly of trade-wind swell
and wind waves.

&&

.Discussion...
As the upper-level low devolves, lobes of upper-level divergence will
be passing through. For now these appear to be centering near Guam
and Rota, because they`re farther south. The effect would be even
larger if they were even farther south.

Tinian and Saipan won`t be left out forever though, looks like closer
to Monday and they will get some action also. So, in the final
analysis, it looks like Guam and Rota especially will get some much
needed rainfall to help the drought end sooner rather than later.

&&

.Marine...
Combined seas of 4 to 6 feet will diminish to between 3 and 5 feet
this afternoon, and could plumb 2 to 4 feet around the middle of next
week. That won`t last long, they will be back up to between 3 and 5
feet by the weekend. Winds will be light to gentle the next several
days, so benign marine conditions will keep on keeping on.

&&

.Eastern Micronesia...
As mentioned in the previous forecast, the Inter-Tropical Convergence
Zone (ITCZ) is expected to go through periods of weakening and
strengthening as it waves north and south over the next few days.
Looking at satellite imagery it looks like the ITCZ is in a weakening
phase as the overall coverage of showers is still fairly scattered
across the region, from the Marshall Islands to Pohnpei, with no
large cluster of heavy showers or thunderstorms concentrated
together. Latest model guidance overnight has not varied much since
yesterday, so little was changed in yesterday`s forecast as ITCZ
looks to move out of the Marshalls starting tonight. This will
result in scattered showers and isolated thunderstorms through today
for Majuro, through Sunday for Kosrae, and Tuesday for Pohnpei. By
early next week, the ITCZ looks to break down, with mostly isolated
showers expected across eastern Micronesia for a short time. Majuro
will see a return in increased convection Monday night as the first
of a series of weak trade-wind troughs move into the area. These
troughs will transit across eastern Micronesia, bringing periods of
increased convection to Kosrae beginning Tuesday evening and to
Pohnpei by Wednesday.

Marine conditions look to remain fairly benign over the next several
days, with seas of 3 to 5 feet across the region, with up to 6 feet
possible at times for Majuro. Light to gentle winds will prevail,
with Majuro seeing occasional moderate trades.

&&

.Western Micronesia...
Satellite imagery and scatterometer data shows a very weak
circulation south of Palau with a broad trough extending over Palau
and up toward Yap. The swirling motion seen in the mid-level clouds
that developed between Palau and Yap overnight, also suggest there
some weak vorticity around the 700 to 400 mb layer. Scattered
showers this morning are mainly west and south of Yap and lifting
into Palau this morning. Over by Chuuk, the weak circulation that
was southeast of Chuuk has opened into a trough, with most of the
convection now south of Pohnpei, so showers are isolated across Chuuk
this morning.

As the weak circulation and mid-level vorticity near Palau and Yap
drift west-northwest, expect scattered showers and isolated
thunderstorms at Palau through Sunday, while Yap will start out
isolated and then scattered showers and isolated thunderstorms will
start to develop around Yap later this afternoon and into tonight. A
day or two of fairer weather is expected late Sunday through Monday
as a ridge moves through, but with light and variable winds we may
see island effect showers and thunderstorms if cloud cover is low.

For Chuuk, as the trough near Pohnpei start to drift westward,
expect showers to increase tonight through Monday, and then
decreasing Tuesday as the trough moves off to the west towards Yap
and Palau.

Yap and Palau buoys are reporting combined seas of 3 to 4 feet, while
altimetry shows seas around 3 to 5 near Chuuk. Expect similar
conditions through next week. Light winds are expected to continue
through early next week at Yap and Palau and light to gentle for
Chuuk.

&&

.GUM WATCHES/WARNINGS/ADVISORIES...
GU...None.
MP...None.
Marianas Waters...None.
&&

$$

Marianas: Stanko
Micronesia: Schank