WPAC: RAMMASUN - Post-Tropical

[cycloneye]

JMA upgrades to TD:

TROPICAL DEPRESSION 1008 HPA AT 09N 152E WNW SLOWLY.

[stormcruisin]

http://www.goes.noaa.gov/guam/guamloops/guamvs.html

[stormcruisin]

Navgem JMA EC all appear to agree on a weak system.
GFS is on there own with this Monster system being posted here
prolly better idea too wait and not scare monger.

[dexterlabio]

It's interesting that Euro was picking up on this system two or three days ago and the forecast track is quite similar with the recent GFS runs. They still kinda picking it up right now but as a disorganized low. For now, GFS and CMC are the only ones calling for a typhoon...while I don't have access on the latest NAVGEM run atm..


EDITED: Thanks for posting the latest NAVGEM, stormcruisin!

[euro6208]

Special Weather Statement NWS Guam 403 pm local time



000
WWMY80 PGUM 100603
SPSMY

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TIYAN GU
403 PM CHST THU JUL 10 2014

GUZ001>004-110600-
GUAM-ROTA-TINIAN-SAIPAN-
403 PM CHST THU JUL 10 2014

...TROPICAL DISTURBANCE NORTH OF CHUUK HEADING TOWARD THE MARIANAS...

AT 100 PM CHST THIS AFTERNOON...A TROPICAL DISTURBANCE WAS
LOCATED NEAR 9 DEGREES NORTH AND 152 DEGREES EAST...WHICH IS
APPROXIMATELY 600 MILES SOUTHEAST OF GUAM AND SAIPAN AND 120 MILES
NORTH OF CHUUK.

SATELLITE IMAGERY SHOWS A WEAKLY DEFINED CENTER MOVING SLOWLY TOWARD
THE NORTHWEST AND THE MARIANA ISLANDS. WHILE STILL POORLY
ORGANIZED...THE SYSTEM HAS DEVELOPED OVER THE PAST 12 HOURS.
ALTHOUGH IT IS STILL TOO EARLY TO TELL WHETHER THIS SYSTEM WILL
BECOME A DIRECT THREAT TO THE MARIANAS...THE NATIONAL WEATHER
SERVICE ON GUAM EXPECTS AN INCREASE IN WINDS AS WELL AS AN INCREASE
IN HEAVY SHOWERS WITH ISOLATED THUNDERSTORMS TO BEGIN SOMETIME
SATURDAY AND CONTINUE INTO SUNDAY. THE NATIONAL WEATHER SERVICE WILL
CLOSELY MONITOR THIS SYSTEM OVER THE NEXT COUPLE OF DAYS AS IT
APPROACHES AND PASSES THE ISLANDS.

STAY INFORMED ON THIS DEVELOPING WEATHER SITUATION. KEEP ABREAST OF
THE LATEST FORECASTS AND LISTEN FOR ANY FURTHER STATEMENTS OR
WARNINGS FROM THE NATIONAL WEATHER SERVICE AND YOUR LOCAL EMERGENCY
MANAGEMENT OFFICE.

$$

MILLER/EDSON/GUARD

[euro6208]

Tropical Cyclone Formation Alert

WTPN21 PGTW 100730
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
150 NM EITHER SIDE OF A LINE FROM 9.5N 152.7E TO 12.9N 146.7E
WITHIN THE NEXT 12 TO 24 HOURS. AVAILABLE DATA DOES NOT JUSTIFY
ISSUANCE OF NUMBERED TROPICAL CYCLONE WARNINGS AT THIS TIME.
WINDS IN THE AREA ARE ESTIMATED TO BE 20 TO 25 KNOTS. METSAT
IMAGERY AT 100700Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 9.9N 151.7E. THE SYSTEM IS MOVING NORTHWESTWARD AT 08 KNOTS.
2. REMARKS: THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 9.8N
152.4E, IS NOW LOCATED NEAR 9.9N 151.7E, APPROXIMATELY 455 NM EAST-
SOUTHEAST OF ANDERSEN AB, GUAM. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY DEPICTS A COMPACT SYSTEM OBSCURING A CONSOLIDATING LOW-LEVEL
CIRCULATION CENTER (LLCC). A 100608Z SSMIS MICROWAVE IMAGE REVEALS
THE BULK OF THE DEEP CONVECTION OVER THE WESTERN SEMI-CIRCLE WITH
FORMATIVE BANDS WRAPPING INTO THE LLCC. AN OLDER 092308Z ASCAT PASS
SHOWED A WELL-DEFINED 10 TO 15 KNOT CIRCULATION AND ISOLATED 20 TO
25 KNOT WIND BARBS OVER THE NORTHERN QUADRANTS. 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
DISTURBANCE IN VARYING DEGREES WITH THE MOST AGGRESSIVE BEING GFS.
MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 20 TO 25 KNOTS.
MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1006 MB. DUE TO
PERSISTENT CONVECTION, IMPROVING ORGANZIATION AND FAVORABLE
CONDITIONS, THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT
TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS HIGH.
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED BY
110730Z.
//
NNNN

[dexterlabio]

Computer models will be able to initialize this system correctly and have a better look of things to come as this disturbance develops further into an organized system. "Wait and see," as always...

[dexterlabio]

Looking at the streamline analysis, this potential storm also has a chance to recurve or at least turn poleward after tracking westward across the Philippine Sea, but unlike Neoguri, the point of recurve could be farther west...near 128 degrees longitude. Looks like Taiwan and northern Luzon will see the effects of a tropical cyclone this time, either weak or significant...

Personal Forecast Disclaimer:
The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.

[cycloneye]

TROPICAL DEPRESSION 1006 HPA AT 10N 151E WNW SLOWLY.

[ManilaTC]

Looking at the streamline analysis, this potential storm also has a chance to recurve or at least turn poleward after tracking westward across the Philippine Sea, but unlike Neoguri, the point of recurve could be farther west...near 128 degrees longitude. Looks like Taiwan and northern Luzon will see the effects of a tropical cyclone this time, either weak or significant...

Personal Forecast Disclaimer:
The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.

I second the motion Dex, once Neoguri moves away and transitions into a XT low. the Subtropical High will build back west and a extension of it to be near Taiwan and North Philippine Sea, forcing the new TD to track more westerly then track NW... but still its long term...

[euro6208]

000
WWMY80 PGUM 100943
SPSMY

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE TIYAN GU
743 PM CHST THU JUL 10 2014

GUZ001>004-110600-
GUAM-ROTA-TINIAN-SAIPAN-
743 PM CHST THU JUL 10 2014

...TROPICAL DISTURBANCE NORTH OF CHUUK HEADING TOWARD THE MARIANAS...

AT 700 PM CHST THIS EVENING...A TROPICAL DISTURBANCE WAS LOCATED
NEAR 10 DEGREES NORTH AND 151 DEGREES EAST...WHICH IS APPROXIMATELY
480 MILES SOUTHEAST OF GUAM AND SAIPAN AND 190 MILES NORTH OF CHUUK.

SATELLITE IMAGERY SHOWS A GRADUALLY DEVELOPING CIRCULATION CENTER
MOVING TOWARD THE NORTHWEST AND THE MARIANA ISLANDS. THIS
CIRCULATION IS NOW THE SUBJECT OF A TROPICAL CYCLONE FORMATION ALERT
FROM THE JOINT TYPHOON WARNING CENTER. THE SYSTEM HAS DEVELOPED OVER
THE PAST 12 HOURS...AND CONDITIONS ARE FAVORABLE FOR FURTHER
DEVELOPMENT. ALTHOUGH IT IS STILL TOO EARLY TO TELL WHETHER THIS
SYSTEM WILL BECOME A DIRECT THREAT TO THE MARIANAS...THE NATIONAL
WEATHER SERVICE ON GUAM EXPECTS AN INCREASE IN WINDS AS WELL AS AN
INCREASE IN HEAVY SHOWERS WITH ISOLATED THUNDERSTORMS TO BEGIN
SOMETIME SATURDAY AND CONTINUE INTO SUNDAY. THE NATIONAL WEATHER
SERVICE WILL CLOSELY MONITOR THIS SYSTEM OVER THE NEXT COUPLE OF
DAYS AS IT APPROACHES AND PASSES THE ISLANDS.

STAY INFORMED ON THIS DEVELOPING WEATHER SITUATION. KEEP ABREAST OF
THE LATEST FORECASTS AND LISTEN FOR ANY FURTHER STATEMENTS OR
WARNINGS FROM THE NATIONAL WEATHER SERVICE AND YOUR LOCAL EMERGENCY
MANAGEMENT OFFICE.

$$

STANKO

[stormcruisin]

The LLCC looks to be suffering from the shear to the N atm.




latest access run is a weak system tracking to the Philippines.

[euro6208]

09W NINE 140710 1200 10.8N 150.5E WPAC 25 1005

09W will be here shortly...

[euro6208]

WTPN32 PGTW 101500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE WARNING//
RMKS/
1. TROPICAL DEPRESSION 09W (NINE) WARNING NR 001
02 ACTIVE TROPICAL CYCLONES IN NORTHWESTPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
101200Z --- NEAR 10.8N 150.5E
MOVEMENT PAST SIX HOURS - 305 DEGREES AT 15 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 025 KT, GUSTS 035 KT
WIND RADII VALID OVER OPEN WATER ONLY
REPEAT POSIT: 10.8N 150.5E
---
FORECASTS:
12 HRS, VALID AT:
110000Z --- 11.9N 149.0E
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 24 HR POSIT: 295 DEG/ 10 KTS
---
24 HRS, VALID AT:
111200Z --- 12.8N 147.2E
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 36 HR POSIT: 285 DEG/ 10 KTS
---
36 HRS, VALID AT:
120000Z --- 13.4N 145.2E
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 035 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 280 DEG/ 11 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
121200Z --- 13.7N 142.9E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
060 NM SOUTHWEST QUADRANT
070 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 275 DEG/ 11 KTS
---
72 HRS, VALID AT:
131200Z --- 14.1N 138.4E
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 090 NM NORTHEAST QUADRANT
080 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
095 NM NORTHWEST QUADRANT
VECTOR TO 96 HR POSIT: 275 DEG/ 10 KTS
---
LONG RANGE OUTLOOK:
---
96 HRS, VALID AT:
141200Z --- 14.4N 134.2E
MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT
WIND RADII VALID OVER OPEN WATER ONLY
VECTOR TO 120 HR POSIT: 290 DEG/ 10 KTS
---
120 HRS, VALID AT:
151200Z --- 15.8N 130.3E
MAX SUSTAINED WINDS - 075 KT, GUSTS 090 KT
WIND RADII VALID OVER OPEN WATER ONLY
---
REMARKS:
101500Z POSITION NEAR 11.1N 150.1E.
TROPICAL DEPRESSION 09W (NINE), LOCATED APPROXIMATELY 372 NM
EAST-SOUTHEAST OF ANDERSEN AFB, HAS TRACKED NORTHWESTWARD AT 15
KNOTS OVER THE PAST SIX HOURS. MAXIMUM SIGNIFICANT WAVE HEIGHT AT
101200Z IS 6 FEET. NEXT WARNINGS AT 102100Z, 110300Z, 110900Z AND
111500Z. REFER TO TROPICAL STORM 08W (NEOGURI) FOR THE FINAL WARNING
(WTPN31 PGTW) FOR SIX-HOURLY UPDATES.
//
NNNN

[euro6208]

Looking like a very wet days ahead for expected Tropical Storm Rammasun...

[mrbagyo]

Looking like a very wet days ahead for expected Tropical Storm Rammasun...

yeah, SCS looks primed for another monsoon barrage for the Philippines.

lots of moisture.

[cycloneye]

JTWC Discussion of 15:00 UTC warning:

Low confidence.


WDPN32 PGTW 101500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 09W (NINE) WARNING
NR 01//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL DEPRESSION (TD) 09W (NINE), LOCATED APPROXIMATELY 372 NM
EAST-SOUTHEAST OF ANDERSEN AFB, HAS TRACKED NORTHWESTWARD AT 15
KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED (EIR)
SATELLITE IMAGERY DEPICTS A COMPACT SYSTEM OBSCURING A RAPIDLY-
CONSOLIDATING LOW-LEVEL CIRCULATION CENTER (LLCC). A 101152Z METOP-A
MICROWAVE IMAGE REVEALS THE BULK OF THE DEEP CONVECTION OVER THE
WESTERN SEMI-CIRCLE WITH TIGHTLY-CURVED BANDING WRAPPING INTO THE
LLCC. THE CURRENT POSITION IS BASED ON THE EIR ANIMATION AND ABOVE
MICROWAVE IMAGE WITH GOOD CONFIDENCE. THE INITIAL INTENSITY IS BASED
ON CONGRUENT DVORAK ESTIMATES FROM PGTW AND KNES. 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.
3. FORECAST REASONING.
A. THIS IS THE INITIAL PROGNOSTIC REASONING AND SETS THE FORECAST
PHILOSOPHY.
B. TD 09W IS CURRENTLY TRACKING ALONG THE SOUTHERN PERIPHERY OF
THE SUBTROPICAL RIGDE (STR) ANCHORED TO THE NORTH. THE STR SYNOPTIC
PATTERN IS FORECAST TO REMAIN THROUGH THE FORECAST PERIOD WITH A
MIDLATUDE SHORTWAVE TROUGH FORECAST TO DEEPEN OVER THE EAST CHINA
SEA NEAR TAU 72. FAVORABLE CONDITIONS REMAIN THROUGHOUT THE FORECAST
PERIOD, ALLOWING THE SYSTEM TO GRADUALLY INTENSIFY.
C. AFTER TAU 72, THE STR IS EXPECTED TO WEAKEN AS THE
AFOREMENTIONED MIDLATUDE TROUGH INFLUENCES THE STEERING ENVIRONMENT,
CAUSING THE DISTURBANCE TO RECURVE AFTER TAU 96. AVAILABLE MODEL
GUIDANCE IS IN TIGHT AGREEMENT; HOWEVER, NUMERICAL MODELS DEVELOP
THIS DISTURBANCE IN VARYING DEGREES WITH THE MOST AGGRESSIVE BEING
GFS. SINCE THIS IS A COMPACT SYSTEM, THE AVAILABLE GLOBAL MODELS
MIGHT NOT RESOLVE THIS SYSTEM CORRECTLY. DUE TO THIS UNCERTAINTY,
THERE IS OVERALL LOW CONFIDENCE TO THE OFFICIAL FORECAST.//

[Alyono]

Just have to raise a point of contention

Why is JTWC saying they are the OFFICIAL forecast, when JMA issues the official forecasts?

[RL3AO]

My guess is they mean official forecast for US DOD interests.

[dexterlabio]

My guess is they mean official forecast for US DOD interests.

I think so.. Military bases in the WPAC follow the JTWC warnings over the JMA, so in a way JTWC warnings are "official" for them. Or it could be simply about the choice of words... maybe they meant "official" as in the only valid forecast coming from their agency, not as the official agency or an RSMC...