WPAC: Ex-Tropical Depression (99W)

[supercane]

Shear really disrupting 99W.

Vis loop:


Latest microwave:


Shear map from CIMSS:

[StormingB81]

So I guess since where it is at with the sheer it has no chance of developing into anything? or how is that forecast looking for later. Is that sheer supposed to stick around?

[StormingB81]

TROPICAL DEPRESSION 1006 HPA AT 22N 132E NW 10 KT.


JMA has it as a Tropical Depression

[KWT]

Hmmmm the shear does look like being an issue, its a bit all over the place to be honest though convection is trying to fire up still.

[StormingB81]

I still think its odd how someone calls it a TD and others don't for awhile and sometimes none at all.

[StormingB81]

99w Is trying to fight back...see what I wake up to tomorrow mornning...

[KWT]

I still think its odd how someone calls it a TD and others don't for awhile and sometimes none at all.

Yeah I've gotta admit the WPAC can be real confusing for things like that, because there are what 3 different agencies at least who operate in the WPAC?

[StormingB81]

JTWC, JMA, PAGASA and HKO..any other? NWS Guam? Anyways what id the probabilty it can strengthen if it goes the same route and comes to okinawa

[KWT]

The ECM does try to develop this weakly as it heads NW but doesn't really ramp it up till its near China on Sunday from the looks of things. So probably just some stormy weather for you guys I'd imagine.

[StormingB81]

Well it is prettyfunny outside now. The lightning is so bright it keeps knocking out the street lights..lol But no rain or thunder

[Typhoon Hunter]

I still think its odd how someone calls it a TD and others don't for awhile and sometimes none at all.

Yeah I've gotta admit the WPAC can be real confusing for things like that, because there are what 3 different agencies at least who operate in the WPAC?

JMA (Japan) is the official RSMC - http://www.jma.go.jp/en/typh/

The main other agencies which issue forecasts are (I have left some out for example Macau:

CWB (Taiwan) - http://www.cwb.gov.tw/eng/index.htm
CMA (China) - http://typhoon.weather.com.cn/
HKO (Hong Kong) - http://www.weather.gov.hk/wxinfo/currwx/tc_pos.htm
KMA (S Korea) - http://web.kma.go.kr/eng/weather/typoon/typhoon.jsp
JTWC (US) - Website doesn't work in Hong Kong so not gonna bother with their link.
NWS Guam also issue forecasts when typhoons are near the Marianas - http://www.prh.noaa.gov/guam/cyclone.php
PAGASA - http://www.pagasa.dost.gov.ph/wb/tcupdate.shtml

If you want official info check out JMA and when a typhoon nears one of the other countries the local met services offer more comprehensive information such as hourly updates etc.

The ones I personally uses when I'm intercepting a typhoon are JMA, CWB, HKO and JTWC in that order of preference.


JTWC (US),

[supercane]

TD (99W) this AM:

12Z JMA analysis:
TROPICAL DEPRESSION 1006 HPA AT 22N 131E NW 10 KT.

IR:


You could perhaps argue for a small circulation and slight banding on microwave imagery:


But does not appear to be a well-defined circulation on the latest ASCAT pass:


Note that even though JMA has classified 99W as a TD, they do not anticipate strengthening to a TD within 24hr, and thus there are no advisories.

All in all agree with JTWC and other agencies on not upgrading this to a TD yet based on that ASCAT pass and decreasing Dvorak classification:

DATE/TIME LAT LON CLASSIFICATION STORM
26/0832 UTC 22.6N 134.0E T1.0/2.0 99W
26/0232 UTC 22.1N 135.2E T1.5/2.0 99W
25/2032 UTC 21.1N 136.7E T2.0/2.0 99W

TXPN29 KNES 260906
SIMWIR

A. TROPICAL DISTURBANCE (99W)
B. 26/0832Z
C. 22.6N
D. 134.0E
E. FIVE/MTSAT
F. T1.0/2.0/S0.0/24HRS
G. IR/EIR/VIS
H. REMARKS...DT OF 1.0 BASED ON .2 BANDING. MET AND PT AGREE. FT BASED
ON DT.
I. ADDL POSITIONS
NIL

...LIDDICK

[Chacor]

There are 14 members of the ESCAP/WMO Typhoon Committee; each one of them (less FS Micronesia, which relies on the US's NWS) issues their own analyses and forecasts. Each is official at a national level; at a regional level the JMA's information should be treated as official.

There is absolutely nothing wrong with agencies disagreeing on the existence of a tropical depression; it happens in the North Atlantic too as France often does not agree with the NHC's assessment of tropical cyclones east of 33°W (which is TPC's High Seas warning boundary).

[Infdidoll]

Wondering if they think this has a chance despite the shear? The last wind analysis I saw didn't look too promising.



And JTWC is giving it a FAIR now...

ABPW10 PGTW 261100
MSGID/GENADMIN/NAVMARFCSTCEN PEARL HARBOR HI/JTWC//
SUBJ/SIGNIFICANT TROPICAL WEATHER ADVISORY FOR THE WESTERN AND
/SOUTH PACIFIC OCEANS REISSUED/261100Z-270600ZAUG2010//
RMKS/
1. WESTERN NORTH PACIFIC AREA (180 TO MALAY PENINSULA):
A. TROPICAL CYCLONE SUMMARY: NONE.
B. TROPICAL DISTURBANCE SUMMARY:
(1) THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 22.6N
135.6E, IS NOW LOCATED NEAR 21.6N 134.6E, APPROXIMATELY 470 NM
SOUTHEAST OF OKINAWA, JAPAN. ANIMATED MULTI-SPECTRAL SATELLITE
IMAGERY AND A 260919Z SSMIS MICROWAVE IMAGE SHOW INCREASED CENTRAL
CONVECTION FLARING OVER A CONSOLIDATING LOW LEVEL CIRCULATION
CENTER (LLCC). UPPER LEVEL ANALYSIS REVEALS THAT THIS SYSTEM IS IN
AN AREA OF LOW VERTICAL WIND SHEAR AND ENHANCED UPPER LEVEL
DIFFLUENCE ASSOCIATED WITH AN ANTICYCLONE DIRECTLY OVER THE SYSTEM
CENTER. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 15 TO 20
KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1006 MB.
DUE TO A MORE CONSOLIDATED LLCC AND INCREASED UPPER LEVEL OUTFLOW,
THE POTENTIAL FOR DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE IN
THE NEXT 24 HOURS IS UPGRADED TO FAIR.
(2) NO OTHER SUSPECT AREAS.
2. SOUTH PACIFIC AREA (WEST COAST OF SOUTH AMERICA TO 135 EAST):
A. TROPICAL CYCLONE SUMMARY: NONE.
B. TROPICAL DISTURBANCE SUMMARY: NONE.
3. JUSTIFICATION FOR REISSUE: UPGRADED AREA IN PARA 1.B.(1) TO
FAIR.//
NNNN

Interesting...If this proves true, Hong Kong's model wasn't too far off the mark after all. Anyway, goodnight or good morning all...I'm off to bed.

[supercane]

There are 14 members of the ESCAP/WMO Typhoon Committee; each one of them (less FS Micronesia, which relies on the US's NWS) issues their own analyses and forecasts. Each is official at a national level; at a regional level the JMA's information should be treated as official.

There is absolutely nothing wrong with agencies disagreeing on the existence of a tropical depression; it happens in the North Atlantic too as France often does not agree with the NHC's assessment of tropical cyclones east of 33°W (which is TPC's High Seas warning boundary).

If this is directed at me, I know all this and have read (and cited here before) the 2010 Typhoon Committee document. When possible, I do try to cite any issuing agency's analysis/forecast. I think I have given a fair reasoning of my understanding of the synoptic situation without disparaging any agency. Based on my analysis, 99W's broad circulation makes declaration of a TD premature, and most of the other agencies in the basin agree. That is all.

[supercane]

The ones I personally uses when I'm intercepting a typhoon are JMA, CWB, HKO and JTWC in that order of preference.

If I may ask why do you rank the centers in this order? I'll admit I like JMA's interim updates of storm position between advisory times.

[KWT]

14 agencies, wow thats quite a few!

I don't think this is a TD at all right now, its getting better right now though for sure in terms of convection but it still looks broad in terms of the circulation.

[Chacor]

There are 14 members of the ESCAP/WMO Typhoon Committee; each one of them (less FS Micronesia, which relies on the US's NWS) issues their own analyses and forecasts. Each is official at a national level; at a regional level the JMA's information should be treated as official.

There is absolutely nothing wrong with agencies disagreeing on the existence of a tropical depression; it happens in the North Atlantic too as France often does not agree with the NHC's assessment of tropical cyclones east of 33°W (which is TPC's High Seas warning boundary).

If this is directed at me

I'm sorry you got that impression; you posted while I was typing up the post. It wasn't meant for you.

[supercane]

All I can say from this microwave image is that if anything is developing, it isn't happening very fast:

[supercane]

I'm sorry you got that impression; you posted while I was typing up the post. It wasn't meant for you.

Sorry, it's all good.