WPAC:SEVERE TROPICAL STORM DUJUAN (0912/13W/LABUYO)

[senorpepr]

WWJP25 RJTD 010600
WARNING AND SUMMARY 010600.
WARNING VALID 020600.
WARNING IS UPDATED EVERY 6 HOURS.
GALE WARNING.
DEVELOPING LOW 1004 HPA
AT 35N 179W NORTH OF MIDWAYS MOVING SOUTHWEST 10 KNOTS.
WINDS 30 TO 35 KNOTS WITHIN 300 MILES OF LOW.
WARNING.
DENSE FOG OBSERVED LOCALLY OVER WATERS BOUNDED BY 40N 150E 46N 151E
51N 157E 52N 170E 60N 175E 60N 180E 44N 180E 37N 170E 40N 157E 40N
150E.
SUMMARY.
TROPICAL DEPRESSION 1000 HPA AT 18N 134E ALMOST STATIONARY.
TROPICAL DEPRESSION 1006 HPA AT 16N 168E WNW 10 KT.
LOW PRESSURE AREA 1004 HPA NEAR 16N 116E ALMOST STATIONARY.
HIGH 1020 HPA AT 41N 132E ALMOST STATIONARY.
HIGH 1022 HPA AT 48N 150E EAST SLOWLY.
HIGH 1024 HPA AT 40N 163E ENE SLOWLY.
WARM FRONT FROM 43N 147E TO 43N 151E 43N 156E.
COLD FRONT FROM 41N 146E TO 39N 145E 37N 142E.
REMARKS.
TROPICAL STORM 0911 KROVANH (0911) 994 HPA AT 42.1N 146.3E : SEE
TROPICAL CYCLONE WARNING.

JAPAN METEOROLOGICAL AGENCY.=

[StormingB81]

Where is this depression I dont see it on JMA or JTWC?

[HURAKAN]

TROPICAL DEPRESSION 1000 HPA AT 18N 134E ALMOST STATIONARY.

[StormingB81]

Awesome Thanks!

[StormingB81]

Looking at that map that other Low became a Depression also..so much for being a poor for the next 12-24 hours. just like that we could have two storms.

[senorpepr]

Looking at that map that other Low became a Depression also..so much for being a poor for the next 12-24 hours. just like that we could have two storms.

The other depression (the one out east by the international dateline) is 02C. However, JMA has now dropped that with the 00Z bulletin.





WWJP25 RJTD 020000
WARNING AND SUMMARY 020000.
WARNING VALID 030000.
WARNING IS UPDATED EVERY 6 HOURS.
GALE WARNING.
DEVELOPING LOW 1000 HPA
AT 44N 153E SEA AROUND KURILS MOVING EASTNORTHEAST 15 KNOTS.
OCCLUDED FRONT FROM 44N 153E TO 44N 155E 44N 156E.
WARM FRONT FROM 44N 156E TO 44N 160E 44N 163E.
COLD FRONT FROM 44N 156E TO 40N 153E 37N 147E.
WINDS 30 TO 45 KNOTS WITHIN 300 MILES OF LOW.
WARNING.
DENSE FOG OBSERVED LOCALLY OVER SEA OF OKHOTSK.
WARNING.
DENSE FOG OBSERVED LOCALLY OVER WATERS BOUNDED BY 40N 142E 43N 141E
46N 151E 54N 166E 55N 180E 36N 180E 39N 160E 40N 142E.
SUMMARY.
LOW 1006 HPA AT 32N 175E WSW 15 KT.
TROPICAL DEPRESSION 1000 HPA AT 18N 134E ALMOST STATIONARY.
LOW PRESSURE AREA 1004 HPA NEAR 16N 114E ALMOST STATIONARY.
LOW PRESSURE AREA 1006 HPA NEAR 07N 158E ALMOST STATIONARY.
HIGH 1016 HPA AT 45N 114E SE 10 KT.
HIGH 1024 HPA AT 46N 143E EAST 15 KT.
HIGH 1020 HPA AT 39N 165E EAST 10 KT.
HIGH 1020 HPA AT 47N 168E EAST 10 KT.

JAPAN METEOROLOGICAL AGENCY.=

[StormingB81]

Question? How can JMA and a philippines site say this storm is a depression and JTWC say it isnt?

[senorpepr]

Question? How can JMA and a philippines site say this storm is a depression and JTWC say it isnt?

Because JMA is the official Regional Meteorological Specialize Center for the WPAC and JTWC is not. Their main customer is the Dept of Defense.

JMA is the lead unit. JTWC can issues their own stuff (i.e. they can issue for a system that JMA hasn't and vice versa and have different intensities).





WWJP25 RJTD 020600
WARNING AND SUMMARY 020600.
WARNING VALID 030600.
WARNING IS UPDATED EVERY 6 HOURS.
GALE WARNING.
DEVELOPED LOW 1004 HPA
AT 45N 156E SEA EAST OF KURILS MOVING EASTNORTHEAST 20 KNOTS.
OCCLUDED FRONT FROM 45N 156E TO 45N 158E 45N 159E.
WARM FRONT FROM 45N 159E TO 45N 162E 44N 165E.
COLD FRONT FROM 45N 159E TO 42N 158E 38N 153E.
WINDS 30 TO 40 KNOTS WITHIN 400 MILES OF LOW SOUTHWEST SEMICIRCLE AND
300 MILES ELSEWHERE.
WARNING.
DENSE FOG OBSERVED LOCALLY OVER SEA OF OKHOTSK.
WARNING.
DENSE FOG OBSERVED LOCALLY OVER WATERS BOUNDED BY 47N 152E 53N 160E
58N 180E 44N 180E 42N 165E 43N 161E 40N 158E 41N 154E 47N 152E.
SUMMARY.
LOW 1004 HPA AT 32N 173E WEST 10 KT.
TROPICAL DEPRESSION 998 HPA AT 18N 134E ALMOST STATIONARY.
LOW PRESSURE AREA 1002 HPA NEAR 15N 116E ALMOST STATIONARY.
LOW PRESSURE AREA 1004 HPA NEAR 09N 161E ALMOST STATIONARY.
HIGH 1024 HPA AT 45N 146E EAST 10 KT.
HIGH 1020 HPA AT 48N 174E EAST 20 KT.

JAPAN METEOROLOGICAL AGENCY.=

[theavocado]

Question? How can JMA and a philippines site say this storm is a depression and JTWC say it isnt?

In addition to what senorpepr said, there is limited data out in the middle of the ocean, so sometimes systems are classified on estimations using the Dvorak method and using check-lists. In this case, JMA might estimate the system to be deeper than JTWC. With so few actual (reliable) observations in that area, there is often disparagy between the groups. They usually become much more consistent on better developed systems.

That said, this system is looking better and better and I fully expect to see something from JTWC soon. I think the fact that it's still pretty broad has been holding it back. They have it as a FAIR on their bulletin right now.

<cut>
(2) THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 17.8N
135.2E, IS NOW LOCATED NEAR 17.5N 132.6E, APPROXIMATELY 695 NM EAST-
NORTHEAST OF MANILA, PHILIPPINES. ANIMATED MULTISPECTRAL IMAGERY
SHOWS A BROAD ELONGATED CIRCULATION WITH CONVECTION PERSISTING NEAR
THE LLCC SUPPORTED BY A 012116Z QUIKSCAT PASS, WHICH INDICATED WINDS
BETWEEN 15 AND 20 KNOTS. UPPER LEVEL ANALYSIS INDICATES THE AREA IS
LOCATED UNDER AN ANTICYCLONE, WHICH IS HELPING TO ENHANCE THE POLE-
WARD AND EQUATORWARD OUTFLOW. VWS AND SST REMAIN FAVORABLE FOR
CONTINUED DEVELOPMENT. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED
AT 15 TO 20 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR
1002 MB. BASED ON GOOD UPPER LEVEL OUTFLOW, FAVORABLE SST AND VWS,
BUT AN ELONGATED LLCC, THE POTENTIAL FOR THE DEVELOPMENT OF A
SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS UPGRADED TO
FAIR.
<cut>

[HURAKAN]

SUBJ/TROPICAL CYCLONE FORMATION ALERT//
WTPN21 PGTW 021500
REF/A/NAVMARFCSTCEN PEARL HARBOR HI/021451Z SEP 09//
AMPN/REF IS TROPICAL CYCLONE FORMATION ALERT (WTPN21 PGTW 021500)//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
A 190 NM RADIUS OF 17.7N 132.5E WITHIN THE NEXT 12 TO 24 HOURS.
AVAILABLE DATA DOES NOT JUSTIFY ISSUANCE OF NUMBERED TROPICAL CY-
CLONE WARNINGS AT THIS TIME. WINDS IN THE AREA ARE ESTIMATED TO
BE 18 TO 22 KNOTS. METSAT IMAGERY AT 021130Z INDICATES THAT A
CIRCULATION CENTER IS LOCATED NEAR 17.6N 132.5E. THE SYSTEM IS
MOVING WESTWARD AT 07 KNOTS.
2. REMARKS:
THIS SUPERSEDES REF A.
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED BY 031500Z.

[HURAKAN]

Looking good

[StormingB81]

Thanks for answering my question hopefully it wasn't a stupid one. I am in Okinawa I will be watching this system closely looks like it can be near us this weekend as a typhoon they are saying See how fast this thing develops

[HURAKAN]

Looking very good

[StormingB81]

This is going to be a typhoon quick!

[HURAKAN]

ZCZC 546
WTPQ20 RJTD 030000
RSMC TROPICAL CYCLONE ADVISORY
NAME TD
ANALYSIS
PSTN 030000UTC 18.2N 130.0E POOR
MOVE W SLOWLY
PRES 996HPA
MXWD 030KT
GUST 045KT
FORECAST
24HF 040000UTC 19.5N 131.2E 120NM 70%
MOVE ENE 07KT
PRES 992HPA
MXWD 035KT
GUST 050KT =
NNNN

[StormingB81]

Everyone has this storm as almost tropical storm (35mph winds) level and yet JTWC still has nothing on it and there are no models up. with this being focasted to be here sat night sunday morning as a severe tropical storm or typhoon they sure are stalling alot.

[Chacor]

06z globals doesn't see much in its future.

FXPQ20 RJTD 030600
RSMC GUIDANCE FOR FORECAST
NAME TD
PSTN 030600UTC 17.8N 128.4E
PRES 996HPA
MXWD 30KT
FORECAST BY GLOBAL MODEL
TIME PSTN PRES MXWD
(CHANGE FROM T=0)
T=06 18.2N 129.6E +001HPA -001KT
T=12 18.2N 130.3E -002HPA +002KT
T=18 18.8N 131.7E -001HPA 000KT
T=24 19.5N 133.0E -004HPA +001KT
T=30 20.2N 134.2E -003HPA +001KT
T=36 21.0N 135.2E -005HPA 000KT
T=42 22.0N 136.4E -004HPA +001KT
T=48 22.9N 137.0E -007HPA -001KT
T=54 23.4N 138.0E -004HPA -002KT
T=60 24.9N 139.2E -006HPA -001KT
T=66 26.4N 140.2E -006HPA +001KT
T=72 27.7N 141.1E -007HPA +001KT
T=78 28.8N 141.9E -005HPA 000KT
T=84 29.5N 142.6E -006HPA +002KT=

[senorpepr]

WTPQ20 RJTD 030900 CCA
RSMC TROPICAL CYCLONE ADVISORY
NAME TD
ANALYSIS
PSTN 030900UTC 17.2N 128.0E POOR
MOVE W SLOWLY
PRES 994HPA
MXWD 030KT
GUST 045KT
FORECAST
24HF 040900UTC 18.1N 129.2E 120NM 70%
MOVE ENE SLOWLY
PRES 990HPA
MXWD 035KT
GUST 050KT =





PAGASA has this system as a tropical storm...

Severe Weather Bulletin Number THREE
Tropical Cyclone ALERT: Tropical Storm "LABUYO"
Issued at 11:00 a.m., Thursday, 03 September 2009

"LABUYO" has intensified into Tropical Storm as it moves in the general direction of Extreme Northern Luzon.

Location of Center:
(as of 10:00 a.m.) 710 kms East of Tuguegarao City
Coordinates: 18.1°N,129.4°E
Strength: Maximum winds of 65 kph near center and Gustiness of up to 80 kph
Movement: West Northwest at 7 kph

Forecast Positions/Outlook:
Friday morning:
590 kms East Northeast of Tuguegarao City or
570 kms East Southeast of Basco, Batanes

Saturday morning:
400 kms East Southeast of Basco, Batanes

Sunday morning:
240 kms East of Basco, Batanes


No Public Storm Warning Signals Raised


This disturbance is expected to enhance the Southwest Monsoon and bring occasional to frequent rains over Southern Luzon, Visayas particularly the western sections.

The public and the disaster coordinating councils concerned are advised to take appropriate actions and watch for the next bulletin to be issued at 11 PM today.

[theavocado]

Everyone has this storm as almost tropical storm (35mph winds) level and yet JTWC still has nothing on it and there are no models up. with this being focasted to be here sat night sunday morning as a severe tropical storm or typhoon they sure are stalling alot.

I don't think this storm is going to make it up to Okinawa that fast. The steering environment is still very week with the sub-tropical ridge so far north. It's starting to look like there might be a reverse oriented monsoon trough in our future, and in that case it will most likely ride up the trough along the southern coast of the Japanese mainland. I'm not sure who is forecasting it to get that strong, but most of the guidance I've seen implies a weak TS by late weekend. Right now the model with the best handle (IMO) is ECMWF, which barely has it as a TS in 72 hours.

I'm a bit surprised that JTWC hasn't warned on this yet, but these types of systems are tricky. It's essentially a monsoon depression right now, which is a system that has been "induced" by the monsoon flow around the eastern end of the monsoon trough. These systems are *very* slow to form and some of the global models (NOGAPS in particular) tend to develop them more rapidly than is observed. One of the hallmarks is the stronger winds tend to be separated from the center, and are more associated with the pressure gradient around the monsoon trough than with the center of the tropical system like a traditional tropical cyclone. Additionally, because of the broad nature, you get lower winds than you would expect from a given central pressure.

In this particular case, Quikscat (see below) shows the system is still elongated and the winds have not fully closed around the northeastern side of the system. This tell me that JTWC might not think this is a Tropical Cyclone yet. That is to say, it hasn't become self sustaining yet and the winds are still associated with the monsoon flow.

[theavocado]

I'm a bit surprised that JTWC hasn't warned on this yet, but these types of systems are tricky.

I may have spoke too soon, I was just on the FNMOC TC Sat page and it appears that 93W is now showing up as 13W. So, it looks like they are writing a warning as I type this and it will be out at 1500Z.