WPAC: NEPARTAK - Post-Tropical

[stormwise]

Small core would not surprise to see a very healthy RI with this TS.

[cycloneye]

JTWC will upgrade to TD.

02W TWO 160702 1800 8.4N 145.0E WPAC 20 1007

[euro6208]

02W TWO 160702 1800 8.4N 145.0E WPAC 20 1007

We now have 02W!

[Yellow Evan]

The wait is over. Finally with a WPAC named storm.

[dexterlabio]

I'm with JMA this time. This is a TS, no doubt.

OT: Looks like the monsoon trough has spawn a weak circulation just off Visayas. Not really knowledgeable about classifying systems though, has anyone seen the same thing or was it just me? Some model runs are showing a weak LPA getting sucked by Nepartak..

[1900hurricane]

I'm with JMA this time. This is a TS, no doubt.

OT: Looks like the monsoon trough has spawn a weak circulation just off Visayas. Not really knowledgeable about classifying systems though, has anyone seen the same thing or was it just me? Some model runs are showing a weak LPA getting sucked by Nepartak..

Here or so? I might have to look at it more. It certainly does look interesting though. Might bring it up in the main WPac thread.

[dexterlabio]

Here or so? I might have to look at it more. It certainly does look interesting though. Might bring it up in the main WPac thread.

Yup that one! It seems to have popped out of nowhere.

[gatorcane]

Impressive indeed, I agree could become a major typhoon

[ManilaTC]

Here or so? I might have to look at it more. It certainly does look interesting though. Might bring it up in the main WPac thread.

Yup that one! It seems to have popped out of nowhere.

Oooh, checked the Himawari loop, its spinning up nicely hehehe

[Yellow Evan]

Looks primed for development. Not too large and has a great moisture envelope and also embedded in a moist environment with a fantastic upper air setup and very warm ocean temps. I'd estimate this attains winds of 135 knots, which considering the runs of the GFs and HWRF does not seem too far fetched,

[cycloneye]

JTWC first warning peaks at 105kts .

[euro6208]

WDPN31 PGTW 030300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 02W (NEPARTAK)
WARNING NR 01//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
ANIMATED MULTISPECTRAL SATELLITE IMAGERY DEPICTS A BROAD AREA OF
DENSE OVERCAST WITH LIMITED FORMATIVE BANDING AND IMPROVED
CONSOLIDATION OVER THE LAST SIX HOURS. A 022145Z 91GHZ SSMIS IMAGE
SHOWS A DEEP VERY CONVECTIVE BAND WRAPPING INTO THE LOW LEVEL
CIRCULATION CENTER FROM THE SOUTH GIVING FAIR CONFIDENCE TO THE
INITIAL POSITION. THE CURRENT INTENSITY IS ASSESSED AT 25 KNOTS
AND IS BASED ON THE IMPROVED CONSOLIDATION AND OBJECTIVE DVORAK
ESTIMATES FROM PGTW, KNES AND RJTD. ENVIRONMENTAL CONDITIONS ARE
CURRENTLY CONDUCIVE FOR INTENSIFICATION WITH RADIAL OUTFLOW ALOFT,
VERTICAL WIND SHEAR VALUES BETWEEN 15 AND 20 KNOTS, AND SEA SURFACE
TEMPERATURES AROUND 31 CELSIUS.
3. FORECAST REASONING.
A. THIS IS THE INITIAL PROGNOSTIC REASONING AND SETS THE FORECAST
PHILOSOPHY.
B. TD 02W WILL REMAIN UNDER A WEAK STEERING ENVIRONMENT OVER THE
NEXT 12 TO 24 HOURS AS A TUTT CELL POSITIONED TO THE NORTH MOVES OFF
TO THE WEST. A SUBTROPICAL RIDGE IS EXPECTED TO BUILD IN FROM THE
NORTHEAST TAKING NEPARTAK ON A NORTHWESTERN TRACK. GRADUAL
INTENSIFICATION IS ANTICIPATED DURING THIS TIME AS OUTFLOW
STEADILY IMPROVES AND THE SYSTEM CONTINUES TO CONSOLIDATE OVER WARM
WATER.
C. IN THE EXTENDED PERIOD NEPARTAK IS FORECAST TO INTENSIFY TO
TYPHOON STRENGTH. ITS SPEED OF ADVANCE IS ALSO FORECAST TO INCREASE
AS IT CONTINUES ON A NORTHWESTERN TRACK UNDER THE INFLUENCE OF THE
SUBTROPICAL RIDGE. BY TAU 120 A TROUGH IS EXPECTED TO MOVE INTO THE
REGION WEAKENING THE STEERING RIDGE AND CAUSING A SHIFT NORTHWARD.
AVAILABLE DYNAMICAL MODEL GUIDANCE IS IN GOOD AGREEMENT, DIFFERING
SLIGHTLY IN THE EXTENDED TAU TRACKS, GIVING HIGH CONFIDENCE TO THE
JTWC FORECAST.//
NNNN

[euro6208]

TXPQ28 KNES 030337
TCSWNP

A. 02W (NEPARTAK)

B. 03/0230Z

C. 8.8N

D. 144.8E

E. THREE/XXXX

F. T2.5/2.5/D1.5/24HRS

G. IR/EIR/VIS

H. REMARKS...DT=3.0 BASED ON .6 BANDING. MET=2.5 BASED ON RAPID
DEVELOPMENT OVER THE LAST 24HRS AND PT=3.0. FT IS BASED ON CONSTRAINT
THAT THE SYSTEM MUST BE LESS THAN OR EQUAL TO 2.5 WITHIN FIRST 24HRS OF
INITIAL CLASSIFICATION.

I. ADDL POSITIONS

NIL

[euro6208]

000
WTPQ31 PGUM 030428
TCPPQ1

BULLETIN
TROPICAL DEPRESSION NEPARTAK (02W) ADVISORY NUMBER 1
NATIONAL WEATHER SERVICE TIYAN GU WP022016
200 PM CHST SUN JUL 3 2016

...TROPICAL DEPRESSION NEPARTAK FORMS EAST OF YAP...

CHANGES WITH THIS ADVISORY
--------------------------
A TROPICAL STORM WARNING IS NOW IN EFFECT FOR FARAULEP
IN YAP STATE.

A TROPICAL STORM WATCH IS NOW IN EFFECT FOR FAIS AND ULITHI
IN YAP STATE.

WATCHES AND WARNINGS
--------------------
A TROPICAL STORM WARNING IS NOW IN EFFECT FOR FARAULEP IN YAP
STATE. A TROPICAL STORM CONDITIONS...INCLUDING WINDS
OF 39 MPH OR MORE...ARE POSSIBLE WITHIN 24 HOURS.

A TROPICAL STORM WATCH IS NOW IN EFFECT FOR FAIS AND ULITHI
IN YAP STATE. A TROPICAL STORM CONDITIONS...INCLUDING WINDS
OF 39 MPH OR MORE...ARE POSSIBLE WITHIN 48 HOURS.

SUMMARY OF 100 PM CHST...0300 UTC...INFORMATION
-----------------------------------------------
LOCATION...9.0N 145.1E

ABOUT 45 MILES NORTHEAST OF FARAULEP
ABOUT 315 MILES EAST OF FAIS
ABOUT 380 MILES EAST OF ULITHI
ABOUT 480 MILES EAST OF YAP AND
ABOUT 310 MILES SOUTH OF GUAM

MAXIMUM SUSTAINED WINDS...35 MPH
PRESENT MOVEMENT...NORTHEAST...035 DEGREES AT 5 MPH

DISCUSSION AND OUTLOOK
----------------------
AT 100 PM CHST...0300 UTC...THE CENTER OF TROPICAL DEPRESSION
NEPARTAK WAS NEAR LATITUDE 9.0 NORTH AND LONGITUDE 145.1 EAST
...MOVING NORTHEAST AT 5 MPH. NEPARTAK IS EXPECTED TO TURN TO THE
NORTHWEST WITH AN INCREASE IN FORWARD SPEED IN THE NEXT 12 HOURS.

MAXIMUM SUSTAINED WINDS ARE AT 35 MPH. STEADY INTENSIFICATION IS
FORECAST AND NEPARTAK COULD BECOME A TROPICAL STORM LATER TODAY.

NEXT ADVISORY
-------------
AN INTERMEDIATE ADVISORY WILL BE ISSUED BY THE NATIONAL WEATHER
SERVICE AT 5 PM THIS AFTERNOON FOLLOWED BY A SCHEDULED ADVISORY
LATER THIS EVENING AT 800 PM CHST.

$$

ZIOBRO

[1900hurricane]

A small core is beginning to develop.

[euro6208]

WDPN31 PGTW 030900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 02W (NEPARTAK)
WARNING NR 02//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
ANIMATED MULTISPECTRAL SATELLITE IMAGERY DEPICTS A CONSOLIDATING
LOW-LEVEL CIRCULATION CENTER WITH CURVED CONVECTIVE BANDING WRAPPING
INTO THE SYSTEM. A 020454Z 37 GHZ SSMI IMAGE REVEALS THIS BANDING IS
MAINLY CONFINED ALONG THE SOUTHERN AND EASTERN PERIPHERY OF THE
SYSTEM, AND SUPPORTS THE JTWC BEST TRACK POSITION WITH GOOD
CONFIDENCE. THE CURRENT INTENSITY IS ASSESSED AT 35 KNOTS BASED ON A
030021Z ASCAT PASS SHOWING A BAND OF 30 KNOT WINDS WITH ISOLATED 35
KNOT WINDS WITHIN DEEP CONVECTION IN THE EASTERN QUADRANT.
ENVIRONMENTAL CONDITIONS ARE CURRENTLY CONDUCIVE FOR INTENSIFICATION
WITH RADIAL OUTFLOW ALOFT, LOW (10 TO 15 KNOTS) VERTICAL WIND SHEAR,
AND WARM SSTS.
3. FORECAST REASONING.
A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS
PROGNOSTIC REASONING MESSAGE.
B. TD 02W WILL REMAIN UNDER A WEAK STEERING ENVIRONMENT OVER THE
NEXT 12 TO 24 HOURS AS A TUTT CELL POSITIONED TO THE NORTH MOVES OFF
TO THE WEST. A SUBTROPICAL RIDGE IS EXPECTED TO BUILD IN FROM THE
NORTHEAST TAKING NEPARTAK ON A NORTHWESTERN TRACK. GRADUAL
INTENSIFICATION IS ANTICIPATED DURING THIS TIME AS OUTFLOW STEADILY
IMPROVES AND THE SYSTEM CONTINUES TO CONSOLIDATE OVER WARM
WATER.
C. IN THE EXTENDED PERIOD NEPARTAK IS FORECAST TO INTENSIFY TO
TYPHOON STRENGTH AT A STEADY RATE. ITS SPEED OF ADVANCE IS ALSO
FORECAST TO INCREASE AS IT CONTINUES ON A NORTHWESTERN TRACK UNDER
THE INFLUENCE OF THE SUBTROPICAL RIDGE, WITH RELATIVELY LOW VWS AND
EXCELLENT UPPER-LEVEL OUTFLOW. BY TAU 120 A TROUGH IS EXPECTED TO
MOVE INTO THE REGION WEAKENING THE STEERING RIDGE AND CAUSING A
SHIFT NORTHWARD. AVAILABLE DYNAMICAL MODEL GUIDANCE IS IN GOOD
AGREEMENT, DIFFERING SLIGHTLY IN THE EXTENDED TAU TRACKS, GIVING
HIGH CONFIDENCE TO THE JTWC FORECAST.//
NNNN

[cycloneye]

 https://twitter.com/RyanMaue/status/749505318065811456

[cycloneye]

 https://twitter.com/MikeAdcockWx/status/749555038188609536

[senorpepr]

Thanks for the post, Luis!

Here's the latest track from JMA... should become a typhoon (10-min average) by Wednesday. Tropics are finally becoming active between this, two more in the EPAC, and a potential third soon.

[Alyono]

 https://twitter.com/RyanMaue/status/749505318065811456

shaking my head at that

You CANNOT use the MU ensemble alone to estimate uncertainty. It has the narrowest ensemble envelope. I can say that other ensembles have a wider dispersion, though its not quite a bifurcation