Mr. INVEST 90W (WPAC)... Disco here

[wxmann_91]

My feeling is this has a much better chance of significant development than Pabuk. Models forecast landfall in Taiwan as a medium intensity storm (no model bombs it really). The monsoonal trough remains hyperactive in the area.

[WindRunner]

Well, the only models I've looked at were 00z 8/06 . . . i.e. yesterday's runs . . . and the CMC/ECMWF/GFS did nothing with it, while as the NOGAPS actually took Pabuk into Taiwan and developed this system at about that point. A brief Fujiwara, and then this thing quickly follows up to the north of Pabuk's track and follows the Chinese coast into the Yellow Sea area . . . ironically enough, that's exactly what the aforementioned consensus did with Pabuk.

I laughed this morning when seeing the differences between the NOGAPS and the rest of the guidance . . . as well as the fact that the JTWC actually took the NOGAPS over the other models . . . but now it looks like it might just verify. From what you posted, it seems like other global models have shifted to a double-barreled Chinese threat as well . . .

Regardless, if this thing had to interfere with Pabuk's inflow from the south, I'm glad it's going to develop as well. At least the monsoon trough is good for something . . .

[Chacor]

It's now a TD:

TROPICAL DEPRESSION 1000 HPA
AT 15.3N 127.5E SEA EAST OF PHILIPPINES MOVING NORTHWEST SLOWLY.
POSITION POOR.
MAX WINDS 30 KNOTS NEAR CENTER.

[RL3AO]

Ooo.

[Typhoon Hunter]

I've been keeping an eye on this blob and as Chacor mentioned this is a TD now. JWTC are listing the area as "POOR."

B. TROPICAL DISTURBANCE SUMMARY:
(1) AN AREA OF CONVECTION HAS PERSISTED NEAR 14.5N 128.7E,
APPROXIMATELY 450 NM EAST OF MANILA, PHILIPPINES. ANIMATED INFRARED
SATELLITE IMAGERY INDICATES A DEVELOPING LOW-LEVEL CIRCULATION
CENTER (LLCC) WITH PERSISTENT DEEP CONVECTION NEAR THE CENTER.
A 061649Z AMSU IMAGE DEPICTS A DEFINED LLCC WITH CONVECTIVE BANDING
SOUTH OF THE CENTER. THERE IS STRONG DEEP CONVECTION OCCURRING WEST
OF THE CENTER, JUST EAST OF LUZON, DUE TO EXCELLENT LOW-LEVEL
CONVERGENCE ENHANCED BY THE TERRAIN. THE UPPER-LEVEL ENVIRONMENT IS
MARGINAL WITH MODERATE VERTICAL WIND SHEAR AND NORTH-NORTHEASTERLY
FLOW ASSOCIATED WITH THE ANTICYCLONE OVER TS 07W. THIS SHEAR, DUE TO
THE PROXIMITY OF TS 07W, WILL REMAIN THE PRIMARY INHIBITOR TO FURTHER
DEVELOPMENT FOR THE NEXT 24-36 HOURS. THIS DISTURBANCE IS LOCATED
IN THE SOUTHERN PERIPHERY OF A LARGE MONSOON DEPRESSION (TS 07W IS
LOCATED IN THE NORTHERN PERIPHERY). MAXIMUM SUSTAINED SURFACE WINDS
ARE ESTIMATED AT 12 TO 18 KNOTS. MINIMUM SEA LEVE PRESSURE IS
ESTIMATED TO BE NEAR 1006 MB. THE POTENTIAL FOR DEVELOPMENT OF A
TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS POOR.

Honk Kong observatory have issued a forecast track for this and expect it to become a severe top storm and make landfall on Taiwan just where Pabuk is forecast to.

[Chacor]

JTWC has upgraded to FAIR.

THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 14.5N
128.7E IS NOW LOCATED NEAR 14.9N 128.7E, APPROXIMATELY 450 NM
EAST OF MANILA, PHIPPINES. RECENT MULTISPECTRAL SATELLITE IMAGERY
SHOWS CONVECTION PERSISTING ALONG THE SOUTHWESTERN PERIPHERY OF
AN INCREASINGLY WELL-DEFINED LOW LEVEL CIRCULATION CENTER. THE
DISTURBANCE LIES IN A REGION OF MODERATE NORTHEASTERLY VERTICAL
WIND SHEAR (VWS) INDUCED BY THE OUTFLOW LAYER ANTICYCLONE OVER
TYPHOON 07W. STRONG SURFACE CONVERGENCE AND UPPER LEVEL DIFFLUENCE
ARE ENHANCING CONVECTIVE BANDING ON THE SOUTHWESTERN PERIPHERY OF
THE LLCC BUT VWS IS INHIBITING THE DEVELOPMENT OF PERSISTENT
CONVECTION OVER THE SYSTEM CENTER. HOWEVER, AS TY 07W MOVES WEST-
WARD AND DISSIPATES, VWS OVER THE DISTURBANCE IS EXPECTED TO
DECREASE. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 15
TO 20 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR
1004 MB. BASED ON IMPROVED LOW LEVEL ORGANIZATION AND THE
FORECAST FOR MORE FAVORABLE UPPER LEVEL CONDITIONS, POTENTIAL
FOR DEVELOPMENT OF A TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS
IS UPGRADED TO FAIR.

[wxmann_91]

I think it's time to take the models w/ a grain of salt.

First of all, the CMC has initialization issues. It has switched back and forth between underestimating the initial strength of STS 07W (and in the latest run) 90W.

ECM tries to merge 90W with the remnants of TS 06W, and takes it S of Taiwan (in the 12Z run). Guess what - according to it, STS 07W doesn't exist.

GFS can always be taken w/ a grain of salt in the WPAC. The OP and the Ensembles just aren't able to see WPAC storms.

Perhaps the NOGAPS is the best model to use (if there's one). The forecast over the next few days over the WPAC is really difficult. Outflow from 07W is hurting 90W, but if it abates, 90W will intensify and start doing Fujiwhara with 07W. Then again, 07W could dissipate quickly and then 90W's intensity will be directly dependent on track (how fast it moves and whether it moves close enough to the Philippines or Taiwan to get hurt). Or 07W can suddenly intensify and start shearing 90W to death.

The conditions are more prime for 90W than 07W... the wet phase of the MJO has pretty much dissipated as it hits the "Wall of Death" of the cooler SST's in the Nino 4 region. The effects can be similar to what happens when a wet MJO leaves - enhanced convection groups together, and the other weaker convection dies... much greater chance of a strong TC developing.

[HURAKAN]

90W (down) & Paduk (up) in the picture:

[alan1961]

Hello guys..could anyone of you post the models for the western pacific please..will be appreciated..thanks

[Typhoon Hunter]

JTWC have now issued a Ttropical Cyclone Formation Alert for 90W. Here's what they say:

WTPN21 PGTW 071000
MSGID/GENADMIN/NAVPACMETOCCEN PEARL HARBOR HI/JTWC//
SUBJ/ TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
120 NM EITHER SIDE OF A LINE FROM 16.3N 127.8E TO 21.0N 123.3E
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 17 TO 22 KNOTS. METSAT IM-
AGERY AT 070600Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 16.5N 127.5E. THE SYSTEM IS MOVING NORTHWESTWARD AT 15
KNOTS.
2. REMARKS: AN AREA OF CONVECTION NEAR 16.5N 127.5E, APPROXIMATELY
395 NM EAST-NORTHEAST OF MANILA, PHILIPPINES, HAS PERSISTED OVER
THE PAST 12 HOURS. RECENT ANIMATED MULTISPECTRAL AND INFRARED
SATELLITE IMAGERY SHOW DEEP CONVECTION FLARING ON THE SOUTH-
WESTERN PERIPHERY OF A CONSOLIDATING LOW LEVEL CIRCULATION CENTER.
ALTHOUGH VERTICAL WIND SHEAR REMAINS MODERATE OVER THE DISTURBANCE
DUE TO UPPER LEVEL OUTFLOW FROM TY 07W, STRONG LOW LEVEL CYCLONIC
SHEAR AND GOOD UPPER LEVEL DIFFLUENCE HAVE ALLOWED THE CIRCULATION
TO CONTINUE TO ORGANIZE. VERTICAL WIND SHEAR OVER THIS DISTURBANCE
IS EXPECTED TO DECREASE AS TY 07W WEAKENS AND MOVES ASHORE. MAXIMUM
SUSTAINED SURFACE WINDS ARE ESTIMATED AT 17 TO 22 KNOTS. MINIMUM
SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1003 MB. DUE TO IMPROV-
ING LOW LEVEL ORGANIZATION AND THE FORECAST FOR DECREASING VERTICAL
WIND SHEAR, THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT
TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS IS GOOD.
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED
BY 081000Z.//

[wxmann_91]

Ack! It looks like while Pabuk has the advantage of anticyclonic upper flow, its thermodynamic environment is impeded. 90W is still being sheared to death and probably has little chance of making major status before hitting Taiwan.

Here's the site for WPAC models:
http://www.meteo.psu.edu/%7Egadomski/ewalltropwpac.html

I wonder if the tropics will heat up ever - anywhere. Maybe all the energy for TC's has been depleted from the 2005 Cane season and Ioke?

[alan1961]

Ack! It looks like while Pabuk has the advantage of anticyclonic upper flow, its thermodynamic environment is impeded. 90W is still being sheared to death and probably has little chance of making major status before hitting Taiwan.

Here's the site for WPAC models:
http://www.meteo.psu.edu/%7Egadomski/ewalltropwpac.html

I wonder if the tropics will heat up ever - anywhere. Maybe all the energy for TC's has been depleted from the 2005 Cane season and Ioke?

much appreciated wxmann_91..thank you

[HurricaneRobert]

So far this year has had one Category 5 cyclone - Gonu in the Arabian Sea.