WPAC: Invest 96W

[1900hurricane]

The next invest has been designated in the WPac. 96W isn't particularly well organized at the moment (even for an invest), receiving no mention yet from JTWC or even a low on the latest JMA surface analysis. 96W is convectively active though, so it does have at least that going for it. American guidance is most bullish with 96W, with both the GFS and GEFS mean showing some development as it crosses the South China Sea. Most other global guidance is less enthusiastic though, with any developing low hardly being distinguishable from the background pressures.



Infrared imagery of 96W actually looks deceptively good at the moment (largely due to the S/SW outflow jet associated with the SW Asian Monsoon), but without any low level structure, there is yet to be any kind of organization present aside for bursting thunderstorms.

[stormwise]

If it can consolidate it may then crank.

[cycloneye]

JMA upgrades to TD.

TD
Issued at 07:20 UTC, 23 June 2016


<Analysis at 06 UTC, 23 June>
Scale -
Intensity -
TD
Center position N11°35' (11.6°)
E118°30' (118.5°)
Direction and speed of movement WNW 25 km/h (13 kt)
Central pressure 1006 hPa
Maximum wind speed near center 15 m/s (30 kt)
Maximum wind gust speed 23 m/s (45 kt)

<Forecast for 18 UTC, 23 June>
Intensity -
TD
Center position of probability circle N13°00' (13.0°)
E115°50' (115.8°)
Direction and speed of movement WNW 25 km/h (13 kt)
Central pressure 1004 hPa
Maximum wind speed near center 15 m/s (30 kt)
Maximum wind gust speed 23 m/s (45 kt)
Radius of probability circle 110 km (60 NM)

<Forecast for 06 UTC, 24 June>
Intensity -
Center position of probability circle N14°20' (14.3°)
E113°35' (113.6°)
Direction and speed of movement WNW 25 km/h (13 kt)
Central pressure 1000 hPa
Maximum wind speed near center 18 m/s (35 kt)
Maximum wind gust speed 25 m/s (50 kt)
Radius of probability circle 200 km (110 NM)

[euro6208]

THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 12.4N
118.6E, IS NOW LOCATED NEAR 13.1N 117.9E, APPROXIMATELY 200 NM WEST-
SOUTHWEST OF MANILA, PHILIPPINES. ENHANCED INFRARED SATELLITE
IMAGERY DEPICTS A BROAD MID-LEVEL CIRCULATION DISPLACED TO WEST-
SOUTHWEST OF AN AREA OF FLARING CONVECTION. A 231315Z ASCAT PASS
SHOWS 10-15 KT WINDS AND AN AREA OF BROAD TROUGHING WITH NO OBVIOUS
CLOSED LOW-LEVEL CIRCULATION CENTER. UPPER-LEVEL ANALYSIS CURRENTLY
INDICATES A MARGINALLY FAVORABLE ENVIRONMENT WITH MODEST OUTFLOW TO
THE WEST BUT RESTRICTED ELSEWHERE, DUE TO THE PRESENCE OF A WEAK
UPPER-LEVEL LOW TO THE WEST AND UPPER-LEVEL TROUGHING SURROUNDING
THE SYSTEM TO THE NORTH. VERTICAL WIND SHEAR REMAINS LOW AROUND 5-10
KTS. GLOBAL MODELS ARE SLOW TO DEVELOP THE SYSTEM AS IT TRACKS
NORTHWESTWARD ACROSS THE SOUTH CHINA SEA. MAXIMUM SUSTAINED SURFACE
WINDS ARE ESTIMATED AT 10 TO 15 KNOTS. MINIMUM SEA LEVEL PRESSURE IS
ESTIMATED TO BE NEAR 1008 MB. DUE TO THE MARGINALLY FAVORALE
ENVIRONMENT BUT NO LLCC, THE POTENTIAL FOR THE DEVELOPMENT OF A
SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24 HOURS REMAINS LOW.

[euro6208]

TXPQ25 KNES 232108
TCSWNP

A. TROPICAL DISTURBANCE (96W)

B. 23/2030Z

C. 14.1N

D. 117.2E

E. THREE/HIMAWARI-8

F. T1.0/1.0/D1.0/24HRS

G. IR/EIR/SWIR

H. REMARKS...LESS THAN .2 CURVED BANDING RESULTS IN A SYSTEM THAT IS
TOO WEAK TO CLASSIFY. MET=1.0 AND PT<1.0. FT IS BASED ON CONSTRAINTS,
WHICH PREVENTS LOWERING THE FT AT NIGHT DURING THE FIRST 24 HOURS OF
DEVELOPMENT.

I. ADDL POSITIONS

NIL


...KIM

[euro6208]

Long range models have this doing a Fujiwhara with the system to the east of the Philippines.

EURO and GFS has a small weak TS making landfall over Central Vietnam.

[euro6208]

TXPQ25 KNES 240304
TCSWNP

A. TROPICAL DISTURBANCE (96W)

B. 24/0230Z

C. 15.4N

D. 114.6E

E. FIVE/HIMAWARI-8

F. TOO WEAK

G. IR/EIR/VIS

H. REMARKS...THIS SYSTEM IS TOO WEAK TO CLASSIFY DUE TO NO LOW LEVEL
CIRCULATION ASSOCIATED WITH THE SYSTEM.

I. ADDL POSITIONS

NIL


...KIBLER

[1900hurricane]

I'm surprised JMA declared this a depression, and I'm even more surprised that they're calling for further development so soon. Scatterometer and microwave passes continue to show any areas of enhanced convergence, let alone an organized circulation.

[1900hurricane]

Ha, beat me to it regarding the circulation. Not sure what JMA is looking at.

[euro6208]

THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 13.1N
117.9E, IS NOW LOCATED NEAR 13.0N 115.2E, APPROXIMATELY 350 NM WEST-
SOUTHWEST OF MANILA, PHILIPPINES. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY DEPICTS A BROAD AREA OF CONVECTION WITH LIMITED
ORGANIZATION. RECENT ASCAT DATA INDICATES TROUGHING IN THE REGION
WITH NO EVIDENCE FOR A CLOSED LOW LEVEL CIRCULATION CENTER (LLCC).
UPPER-LEVEL ANALYSIS INDICATES A MARGINAL ENVIRONMENT WITH MODEST
OUTFLOW TO THE WEST BUT RESTRICTED ELSEWHERE, DUE TO THE PRESENCE OF
A WEAK UPPER-LEVEL LOW TO THE EAST CREATING 15-25 KNOTS OF VERTICAL
WIND SHEAR. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 10 TO
15 KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1008
MB. DUE TO THE MARGINAL ENVIRONMENT THE POTENTIAL FOR THE
DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN THE NEXT 24
HOURS REMAINS LOW.

[wxman57]

Ha, beat me to it regarding the circulation. Not sure what JMA is looking at.

I saw no circulation on the ASCAT from yesterday morning. I've noticed that the JMA tends to be very liberal in what they identify as a "depression". It seems that any slight area of low pressure gets classified as a "depression", whether or not it meets the typical definition.

[euro6208]

THE AREA OF CONVECTION (INVEST 96W) PREVIOUSLY LOCATED
NEAR 13.0N 115.2E, IS NOW LOCATED NEAR 14.9N 113.2E, APPROXIMATELY
335 NM EAST-SOUTHEAST OF HUE, VIETNAM. ANIMATED INFRARED SATELLITE
IMAGERY DEPICTS WEAK LOW-LEVEL TROUGHING WITH ISOLATED FLARING
CONVECTION DISPLACED TO THE SOUTH. A 241033Z WINDSAT PASS SHOWS
LIGHT 10-15 KNOT WINDS ASSOCIATED WITH THE TROUGHING. VERTICAL WIND
SHEAR REMAINS LIGHT (10-15 KNOTS), HOWEVER, THERE IS VERY LITTLE
UPPER LEVEL OUTFLOW AT THIS TIME. GLOBAL MODELS GENERALLY MAINTAIN
96W AS A WEAK CIRCULATION THAT TRACKS INTO VIETNAM OVER THE NEXT TWO
DAYS. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 10 TO 15
KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1007 MB.
THE POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE
WITHIN THE NEXT 24 HOURS REMAINS LOW.

[stormwise]

ZCZC 811
WTPQ20 RJTD 250600
RSMC TROPICAL CYCLONE ADVISORY
NAME TD
ANALYSIS
PSTN 250600UTC 14.3N 113.8E POOR
MOVE W SLOWLY
PRES 1006HPA
MXWD 030KT
GUST 045KT
FORECAST
24HF 260600UTC 14.6N 113.1E 110NM 70%
MOVE WNW SLOWLY
PRES 1000HPA
MXWD 035KT
GUST 050KT =
NNNN

[euro6208]

Something interesting might unfold.

CMC and NAVGEM has this swallow 97W or vice versa and becomes a large monsoon system in the SCS. 12Z and 00Z CMC then takes this to Northern Hainan/Southern China.

GFS and EURO still null on development.

[RL3AO]

12Z position was at 14N 114E. Here is an ASCAT pass from 13Z.

Sure JMA can get a little liberal with calling things depressions...but this is pretty out there.

[stormwise]

https://ams.confex.com/ams/annual2003/t ... _56496.htm

[1900hurricane]

12Z position was at 14N 114E. Here is an ASCAT pass from 13Z.

Sure JMA can get a little liberal with calling things depressions...but this is pretty out there.

Yeah, agree completely. There has been nothing going on with this invest in terms of low-level organization.

[stormwise]

Gyre..

[1900hurricane]

As 96W prepares to move inland over Vietnam, the circulation appears too broad and devoid of convection to be classified as a tropical depression, but does look like a monsoon depression.