WPAC: RAMMASUN - Post-Tropical

[dexterlabio]

The timing of its formation coincides with the expected strengthening of MJO which is now over the Maritime Continent.


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Looks like a wet weather setup for the WPAC and SE Asia continues after Neoguri...

[euro6208]

JTWC upped the chance to LOW!

AN AREA OF CONVECTION HAS PERSISTED NEAR 7.3N 154.4E,
APPROXIMATELY 150 NM EAST OF CHUUK. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY DEPICTS A BROAD AND ILL-DEFINED LOW-LEVEL CIRCULATION CENTER
WITH FLARING AND DISORGANIZED CONVECTION. A 082328Z ASCAT PASS SHOWS
A HIGHLY DISORGANIZED AND ELONGATED CIRCULATION WITH 10 TO 15 KNOT
WINDS. SEA SURFACE TEMPERATURES IN THE REGION ARE CONDUCIVE FOR
DEVELOPMENT. UPPER-LEVEL ANALYSIS REVEALS A FAVORABLE ENVIRONMENT AS
HIGHLY DIFFLUENT OUTFLOW THAT IS BEING ENHANCED BY A TUTT CELL
LOCATED NORTHEAST OF THE SYSTEM. MAXIMUM SUSTAINED SURFACE WINDS ARE
ESTIMATED AT 10 TO 15 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED
TO BE NEAR 1010 MB. THE POTENTIAL FOR THE DEVELOPMENT OF A
SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS LOW.

[cycloneye]

NWS GUAM says there is uncertainty about this in terms of intensity and track as it moves thru the Marianas longitude.

LIGHT WINDS AND ISOLATED SHOWERS ARE ALL THAT IS EXPECTED THE
NEXT FEW DAYS. THE BIG DEBATE IS WHAT WILL HAPPEN TO A
CIRCULATION NOW LOCATED BETWEEN CHUUK AND POHNPEI. MOST MODELS DO
DEVELOP IT. THE GFS MAKES IT THE STRONGEST WHILE THE OTHER MODELS
KEEP IT WEAK.

GFS40 AND GFS ENSEMBLE PASS THE CIRCULATION NEAR ROTA ON SUNDAY
AT 6Z. ECMWF PASSES IT SOUTH OF GUAM SUNDAY NIGHT. NAVGEM IS
SIMILAR TO THE GFS AND GFS ENSEMBLE ONLY IT IS WEAKER. THE GFS
MODELS BOTH SHOWED IT PASSING NORTH OF SAIPAN YESTERDAY. SO THE
TREND OF THE GFS SEEMS TO BE TRACKING THE SYSTEM FURTHER SOUTH.
WILL THE GFS MODELS AND ECMWF EVENTUALLY AGREE ON THE CIRCULATION
PASSING CLOSE TO BUT SOUTH OF GUAM?

NO MATTER WHAT IT EVENTUALLY BECOMES OR THE TRACK IT TAKES...
MOST LIKELY IT SHOULD PRODUCE SOME RAIN. THE MOST LIKELY TIME IS
SUNDAY NIGHT THROUGH MONDAY NIGHT SO ADDED SCATTERED SHOWERS TO
THE FORECAST THEN.

BECAUSE ONE MODEL SHOW THE CIRCULATION PASSING NORTH OF GUAM AND
ONE SOUTH WIND FORECAST IS UNCERTAIN. WITH THE MODELS SO MIXED ON
WINDS AND WIND DIRECTIONS CAN ONLY CAN VOUCH FOR WIND FORECAST
THROUGH SATURDAY AFTER THAT UNCERTAINTY BECOMES GREATER.

[xtyphooncyclonex]

What does the CMC show in their latest run? It is more or less the best performer this year, in terms of forecasting formation of a typhoon, and did close calls to many storms.

[stormcruisin]

What does the CMC show in their latest run? It is more or less the best performer this year, in terms of forecasting formation of a typhoon, and did close calls to many storms.

EC along the same lines as global model no interest in TY atm.

[cycloneye]

12z Best Track:

92W INVEST 140709 1200 8.3N 154.1E WPAC 15 1010

[euro6208]

Superb outflow linked to a TUTT cell and quite small and in a very very favorable environment...

I see JTWC upgrading potential to Medium very soon...

[cycloneye]

It looks like it may be Taiwans turn to have a hit by a strong Typhoon if the models verify.

[cycloneye]

12z GFS shows a monster threatening Taiwan but a little bit north of past runs.Yes,that is 910 mbs.

[cycloneye]

It looks like is organizing at a steady pace.

[cycloneye]

18z Best Track:

92W INVEST 140709 1800 8.3N 152.7E WPAC 15 1010

[cycloneye]

Ummm,is interesting that ECMWF doesn't develop this.

[Hurricane_Luis]

Ummm,is interesting that ECMWF doesn't develop this.

Nothing new there then. Although the latest GFS run does.

[cycloneye]

THis is the latest Guam NWS discussion about 92W.

NAVGEM STILL DOES NOT HAVE A HANDLE ON 92W...SO GRID UPDATES WERE
BASED ON THE LATEST RUNS OF THE GFS AND ECMWF. BOTH THE ECMWF AND
GFS ARE TRENDING TOWARD THE SOUTH WITH THE FORECAST TRACK OF 92W.
AM BUYING INTO THIS TREND...AS UPPER-LEVEL ENVIRONMENT TO THE
NORTH OF 92W LOOKS QUITE HOSTILE WITH EXTENSIVE MID TO UPPER-
LEVEL TROUGHING IN PLACE TO THE NORTH OF 92W. WATER VAPOR LOOP
ALSO SUGGESTS MID-LEVEL RIDGING IS BEGINNING TO BUILD OVER
92W...WHICH SHOULD HELP THIS RELATIVELY SMALL SYSTEM STEER CLOSER
TO WEST VERSUS NORTHWEST. BASED UPON ALL OF THIS...REDID WINDS
DAYS 2 THRU 8. GRID UPDATES TRACK 92W ON A FASTER TRACK SOUTH OF
GUAM SATURDAY NIGHT AND SUNDAY. ADDED SCATTERED SHOWERS TO THE
FORECAST GRIDS BEGINNING ON SATURDAY NIGHT ACCORDINGLY. KEPT
SCATTERED SHOWERS IN THE FORECAST FOR MONDAY AND MONDAY NIGHT AS
DEEP MOISTURE REMAINS IN PLACE FOLLOWING THE PASSAGE OF 92W. THE
GFS AND ECMWF BOTH SUGGEST THE TROPICAL DISTURBANCE NORTHEAST OF
POHNPEI COULD EVENTUALLY FOLLOW A TRACK SIMILAR TO THAT OF 92W AND
AFFECT THE FORECAST ZONES AROUND THE MIDDLE OF NEXT WEEK. STRONGER
RIDGING IN PLACE TO THE NORTH OF THESE SYSTEMS WOULD DELAY ANY
NORTHWARD MOVEMENT OF THE MONSOON TROUGH...SO HAVE DELAYED PASSAGE
OF THE TROUGH TO THE NORTH OF THE FORECAST ZONES UNTIL DAY 8.

[xtyphooncyclonex]

I guess this may pan out due to the high consistency bstween GFS & CMC with this potential typhoon.

[StormingB81]

Looking at the Forecast for Okinawa....With all that flooding there is a lot of rain foretasted for the next few days..if it does that and this comes anywhere close it could mean huge trouble for Okinawa..not saying thats where it is going however just saying if it ends up happening and not even this one any one anytime soon

[cycloneye]

00z Best Track:

92W INVEST 140710 0000 9.1N 151.8E WPAC 20 1007

[stormcruisin]

Maybe the EC is sickly wrong with this invest or its the other disturbance mentioned in the discussion that follows that develops into the system modeled to bomb will be interesting to see what models are on the mark. GFS and cmc are always bullish most of the time.

[cycloneye]

Is this one. JTWC upgraded to Medium.

THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 7.3N
154.4E, IS NOW LOCATED NEAR 9.1N 151.8E, APPROXIMATELY 103 NM NORTH
OF CHUUK, FSM. ANIMATED MULTISPECTRAL SATELLITE IMAGERY SHOWS A
COMPACT SYSTEM THAT HAS BEGUN TO CONSOLIDATE AS FORMATIVE BANDS
ARE WRAPPING TIGHTER INTO AN OBSCURED LOW-LEVEL CIRCULATION CENTER.
UPPER-LEVEL ANALYSIS INDICATES A FAVORABLE ENVIRONMENT WITH DUAL
OUTFLOW - ONE ENHANCED BY A TUTT CELL TO THE NORTHEAST AND A
WESTWARD OUTFLOW ENHANCED BY THE STRONG EASTERLY WINDS ALONG THE
SOUTHERN PERIPHERY OF THE RIDGE TO THE NORTH. NUMERIC WEATHER
PREDICTION MODELS DEVELOP THIS AREA IN VARYING DEGREES WITH THE MOST
AGGRESSIVE BEING GFS. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED
AT 15 TO 20 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE
NEAR 1007 MB. DUE TO THE IMPROVING ENVIRONMENTAL CONDITIONS, THE
POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE
WITHIN THE NEXT 24 HOURS IS UPGRADED TO MEDIUM.

[stormcruisin]

JMA model.