WPAC: INVEST 98W

[cycloneye]

INFARED LOOP

VISIBLE LOOP

[xtyphooncyclonex]

If this GFS run from 25/12z verifies, this would be my first time to have experienced typhoon-strength winds and a direct hit from a typhoon.



CMC agrees... somewhat weaker. Strong TS though

[cycloneye]

950 mbs at landfall.

[cycloneye]

Latest position of 98W is almost at the equator.

As of 18:00 UTC Dec 25, 2017:

Location: 0.9°N 162.2°E
Maximum Winds: 15 kt
Minimum Central Pressure: 1010 mb

[cycloneye]

Convection has increased over the LPA.

[euro6208]

98W INVEST 171226 0000 2.3N 161.4E WPAC 15 1007

Up to 2.3N of the equator.

[xtyphooncyclonex]

[euro6208]

619
FXPQ60 PGUM 260809
AFDPQ

Area Forecast Discussion
National Weather Service Tiyan GU
610 PM ChST Tue Dec 26 2017

.Marianas Synopsis...
A dry trade-wind pattern persists across the region. After a nearly
cloud-free morning, low-level clouds have moved back into the
Marianas.

&&

.Discussion...
The dry trade-wind pattern will persist for the rest of this week
with moderate to fresh winds. A disturbance south of Pohnpei and
Kosrae is beginning to slowly move west. Late in the week, as it
passes well south of Guam, clouds are expected to increase in the
Marianas. Models show showers increasing just south and west of Guam
as the disturbance passes, but I am hesitant to reflect a change in
the current forecast from isolated showers as models have been over-
forecasting westward motion of these disturbances much of the past
few weeks. A little westward motion of the disturbance, seen in
satellite imagery, could be indication that the disturbance is
finally on the move.

In the long range, models show a couple of shear lines approaching
the Marianas. The first is expected to stall out northwest of the
area this weekend, but the second could reach the islands late next
week.

&&

.Marine...
A long-period north-northwest swell will reach the Marianas on
Thursday. This will cause surf along west and north facing to build
a couple of feet, increasing the risk of rip currents to moderate
along those reefs. Seas will otherwise range between 6 and 8 feet the
next few days. The next couple of shifts will need to keep an eye on
surface winds and buoy data in the event trade- wind swell build
another foot or two. In that case, the risk of rip currents could
become high.

&&

.Eastern Micronesia...
A weak circulation southeast of Pohnpei will continue moving
slowly west-northwestward. This feature may bring scattered
showers to Pohnpei overnight. This circulation has weakened with
time and looks much less organized than it did even 24 hours ago.
The rest of eastern Micronesia looks to be fairly quiet for the
mid and late week period. I kept thunder in the forecast through
Wednesday for Pohnpei and Kosrae until the circulation moves
further west, then just general showers. This disturbance will
then bring scattered showers to Chuuk on Wednesday.

The high surf advisory will remain in effect for Kosrae through
Wednesday and for Majuro through tonight. Conditions should begin
to slowly decrease. Seas will remain hazardous for small craft at
Pohnpei and Majuro through tonight and Kosrae through Wednesday,
and Chuuk through Wednesday night.

&&

.Western Micronesia...
Koror will start of with some scattered showers early tonight due
to a trade wind disturbance, otherwise western Micronesia looks
fairly quiet through the end of the week. Then, all of the
guidance suggests that the circulation over eastern Micronesia
will develop around Friday and could bring more clouds, scattered
showers and isolated thunderstorms to Koror and Yap Friday into
Saturday. The guidance still differs on the timing and track of
the system, so its possible that weather could end up Saturday and
Sunday instead of Friday and Saturday, but it is worth adding
something into the forecast at this point and making changes from
there.

&&

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

$$

W. Aydlett/Nierenberg

[euro6208]

[cycloneye]

18:00 UTC position:

Location: 2.8°N 160.3°E
Maximum Winds: 15 kt
Minimum Central Pressure: 1010 mb



Models agree on track and intensity now as they go to Mindanao as a Tropical Storm.We saw how many people dies from the last TS Tembin due to extensive floodings and mudslides so it is not have to be a Typhoon.

[xtyphooncyclonex]

Interesting agreement here

UKMET - consistent; showing a typhoon



ECMWF - most consistent; showing a strong TS or entry-level STS



GFS - weakest and least consistent

[xtyphooncyclonex]

Tropical cyclogenesis is very likely, near-certainty. The risk of formation is already high for the next two weeks.

[euro6208]

One thing is for sure. Whether or not this develops, it will dump even more rain onto areas affected by Tembin and Kai-tak. Grounds already saturated and more water will cause more landslide and flooding.

[doomhaMwx]

The Navy has dropped this 24hrs ago.
Area of convection well to the south of Guam likely to be our next Invest.