WPAC: TEMBIN - Post-Tropical

[tatlopuyo]

I think that is another another storm way east. Latest ecmwf doesnt show it too hitting the philippines anymore. Might be just an error from both gfs and ecmwf?

[mrbagyo]

I think that is another another storm way east. Latest ecmwf doesnt show it too hitting the philippines anymore. Might be just an error from both gfs and ecmwf?

saw the latest euro, I'm out of word. What happened?
Crazy swing around

[1900hurricane]

Looks like I'll be waiting for the 12Z guidance before doing my blog.

[doomhaMwx]

00Z GFS run develops another system to the east of 97W instead. The 00Z ECMWF is quite similar to 00Z GFS solution.

[dexterlabio]

Looks like the models are seeing this system dissipating in the coming days, then spewing another one to become a crazy intense STY. I think I've seen this scenario play out countless times this year in WPAC...

[euro6208]

Remains MEDIUM

THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 2.3N
148.9E, IS NOW LOCATED NEAR 4.4N 146.0E, APPROXIMATELY 392 NM
SOUTHWEST OF CHUUK. ANIMATED MULTISPECTRAL SATELLITE IMAGERY AND A
160502Z 89GHZ SSMI IMAGE DEPICT AN ELONGATED AND ILL-
DEFINED LOW LEVEL CIRCULATION CENTER (LLCC) WITH SCATTERED
CONVECTION OVER THE NORTHERN AND WESTERN PERIPHERIES. A 152315Z
OSCAT IMAGE SHOWS AN ELONGATED TROUGH WITH NO EVIDENCE OF A CLOSED
SURFACE CIRCULATION, WITH STRONGER WINDS ON THE EASTERN SIDE
EMBEDDED WITHIN THE CONVECTION. UPPER LEVEL ANALYSIS DEPICTS LOW TO
MODERATE (10-15 KNOTS) VERTICAL WIND SHEAR AND FAVORABLE DIFFLUENCE
ALOFT. ADDITIONALLY, THE DISTURBANCE IS LOCATED IN AN AREA OF
FAVORABLE SEA SURFACE TEMPERATURES (30-31 CELSIUS) THAT WILL SUPPORT
FUTURE DEVELOPMENT. GLOBAL MODELS ARE IN GOOD AGREEMENT THAT THE
DISTURBANCE WILL TRACK WEST-NORTHWESTWARD OVER THE NEXT 48 HOURS
WITH STEADY DEVELOPMENT. MAXIMUM SUSTAINED SURFACE WINDS ARE
ESTIMATED AT 15 TO 20 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED
TO BE NEAR 1004 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A
SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS REMAINS MEDIUM.

[euro6208]

Incredibly deep convection...

[euro6208]

The NWS of the region starting to notice.

A monsoon trough stretches southeastward from TS Kai-Tak to a
developing tropical disturbance, Invest 97W, centered well to the
south of Guam. Converging winds north of the trough brought scattered
showers and a few thunderstorms to Guam and Guam waters early this
afternoon. Decided to go ahead and add isolated thunderstorms to the
remainder of the Marianas due to marginal instability across the
area. Otherwise, no changes beyond tonight. Models continue to
struggle with the outcome of Invest 97W. Latest model guidance now
shows this system weakening and a new one developing farther south
and east. The ECMWF develops this new system south of Chuuk, while
the GFS has it further east, developing south of Pohnpei. This
situation will need to be monitored very closely over the next couple
of days.

Invest 97W, now well south of Guam, remains the focus over Micronesia
this afternoon. There is a lot of uncertainty with this system.
Latest model guidance indicates this system will slowly dissipate and
another will form farther south and east. Due to the uncertainty,
this situation will be monitored closely over the next few days.
Regardless, a fairly wet pattern is likely over western Micronesia
and, depending on how the disturbances develop, could push northward
into the Marianas.

The Special Weather Statement was re-issued and High Surf Advisory
remains for Koror. TS Kai-Tak is moving away northwest, while the
monsoon trough runs southeastward over Yap through the disturbance
southwest of Chuuk near 3.5N148E; Invest Area 97W. The pattern is
complicated and there may be several small circulations in the
monsoon trough, and the weather moving across Yap this afternoon
seems to be associated with a mid-level circulation. Models differ
widely on development and movement of 97W. GFS and WW3 Wave Model
still seem too aggressive. Current forecast follows continuity with
previous forecasts with a few small upward adjustments. The main
circulation thats associated with Invest 97W is expected to move
slowly toward west-northwest and gradually develop further over the
next few days, and the situation will need to be monitored very
carefully.

[euro6208]

06Z GFS is back to developing this somewhat. Big Palau landfall and peak of 892 mb...

[euro6208]

HWRF with a Cat 3...

[1900hurricane]

Looks like the center is trying to establish itself here.

[1900hurricane]

Mid-layer shear is something to watch. The PTKK (Truuk) sounding from 12Z had easterlies anywhere between 25-40 kt in the 500-300 mb layer.



Other than that though, it's worth noting the EL at the tropopause near 100 mb, where it's about -85ºC.

[cycloneye]

About the 12z GFS run=Is crazy.

[1900hurricane]

About the 12z GFS run=Is crazy.

Not touching that run with a 39 and a half foot pole. The GFS has been lost out here lately.

[tatlopuyo]

12z euro doesnt develop anything anymore at all.

[1900hurricane]

Looks like guidance might be flattening 97W with a trade surge coupled with reduced equatorial westerlies. If it can't remain independent of the monsoon trough, it might be done in a day or two.

[cebuboy]

Can anyone estimate the percent probability that this would landfall in Visayas/Mindanao region? I'm planning to go out this Christmas season but I would rather stay home if this storm will be forecasted to pass the islands.

I would like to see the long term forecast of this storm. But as of now I don't see a clear consensus. Maybe its too early to tell.
Thanks.

[euro6208]

Very detailed discussion from NWS this morning.

Models have been struggling with 97W, with rather large run-to-run
variations in how they handle it. But the 12Z runs of the GFS and
ECMWF are in fairly good agreement in stretching 97W out into a
NW-SE trough over the next couple of days, which looks reasonable.
This reduces the expected winds a little for the Marianas the next
few days, and this is reflected in the forecast. Otherwise, weather
remains the same, with isolated showers through the forecast period,
and breezy conditions Tuesday and Wednesday.

On satellite imagery, 97W appears to be separating into two distinct
entities; one east of Yap near 8N142E, and the other well southwest
of Chuuk near 2N148E, with the two connected by a trough. The GFS
and ECMWF both depict a weak circulation under the cloud mass east
of Yap, which is supported by the evening ASCAT surface wind
analysis, while the GFS also has a weak elongated circulation under
the other cloud system. Winds aloft are very strong over the Yap
system, ranging from 30 kt to near 50 kt, mainly from the east. The
ECMWF quickly wipes out the Yap system, and weakens the trough as
well over the next few days. The GFS also opens the Yap system into
a trough by this evening, but it takes the other cloud mass SW of
Chuuk and develops it into a tropical depression Tuesday night and
Wednesday well south of Chuuk near 1N152E. With strong upper winds
and fair model agreement, the demise of the Yap circulation seems
likely, and indeed it appears to be losing organization on the
satellite loop. The development of the other system seems doubtful,
especially as the ECMWF shows nothing developing in that area. In
fact, the ECMWF develops nothing at all anywhere over the next ten
days.

The tropical/monsoonal disturbance, JTWC Invest Area 97W is slowly
drifting west-northwestward and is near 8N142E this morning. Latest
ASCAT satellite imagery indicates converging fresh to strong monsoon
winds west and south of 97W. Aided by strong divergent east-southeast
flow of 30 to 45 knots above 500mb, widespread deep convection
continues to flare up near the disturbance and is then being sheared
toward the west. This vertical wind shear should hinder 97W from
developing further thru at least Monday night. The western edge of
this convection is already reaching Yap coastal waters this morning
and will likely spread over Yap this afternoon. The lower atmosphere
near Yap might stabilize itself and cause convection to weaken this
evening. With conditions still conducive for upward motion, deep
convection is expected to reform later tonight and Monday. This
convection can produce 2 to 4 inches of rainfall across western Yap
State by Monday afternoon. Converging fresh west to northwest winds
near Koror will also trigger periodic showers and thunderstorms
there thru Monday. As 97W drifts toward Koror on Monday night and
Tuesday, there will be the potential for heavy rainfall as well.
The GFS is forming a secondary circulation near the southeastern
end of the monsoon trough southwest of Chuuk near midweek. If so,
it will probably sustain an unstable monsoonal regime across far
western Micronesia most of this week.

[xtyphooncyclonex]

GFS again... on Christmas Day



Here's why the GFS has this ramping up again

[Digital-TC-Chaser]

Boms model is still developing a system over xmas.





Basicly its the ukmet unified run by the bom.


Is it the system behind 97w that ramps up.or does TD 97w collapse and regenerate?.

TROPICAL DEPRESSION 97W ANALYSED POSITION : 7.3N 144.2E

VERIFYING TIME POSITION STRENGTH TENDENCY
-------------- -------- -------- --------
12UTC 16.12.2017 7.3N 144.2E WEAK
00UTC 17.12.2017 6.6N 144.5E WEAK LITTLE CHANGE
12UTC 17.12.2017 6.6N 143.9E WEAK LITTLE CHANGE
00UTC 18.12.2017 BELOW TROPICAL STORM STRENGTH

NEW TROPICAL STORM FORECAST TO DEVELOP AFTER 78 HOURS
FORECAST POSITION AT T+ 78 : 7.5N 136.4E

VERIFYING TIME POSITION STRENGTH TENDENCY
-------------- -------- -------- --------
00UTC 20.12.2017 7.5N 136.6E MODERATE LITTLE CHANGE
12UTC 20.12.2017 8.3N 135.4E MODERATE INTENSIFYING SLIGHTLY
00UTC 21.12.2017 8.9N 134.1E MODERATE INTENSIFYING SLIGHTLY
12UTC 21.12.2017 9.2N 133.1E STRONG INTENSIFYING SLIGHTLY
00UTC 22.12.2017 9.4N 132.4E STRONG INTENSIFYING SLIGHTLY
12UTC 22.12.2017 9.7N 131.0E INTENSE INTENSIFYING SLIGHTLY]

http://tgftp.nws.noaa.gov/data/raw/fx/fxxt03.egrr..txt