WPAC: NEPARTAK - Post-Tropical

[dexterlabio]

So which storm do you think will be the first Cat3 of the NHem this 2016? Will it be Nepartak or Blas? Would be fun to turn this to a betting game.

[Alyono]

looks like a 5.0 to me

[NotoSans]

JMA upgrades to Typhoon Nepartak.

TY 1601 (Nepartak)
Issued at 00:50 UTC, 5 July 2016
<Analysis at 00 UTC, 5 July>
Scale -
Intensity Strong
Center position N15°10' (15.2°)
E136°35' (136.6°)
Direction and speed of movement WNW 30 km/h (17 kt)
Central pressure 970 hPa
Maximum wind speed near center 35 m/s (70 kt)
Maximum wind gust speed 50 m/s (100 kt)
≥ 50 kt wind area ALL 90 km (50 NM)
≥ 30 kt wind area NE 330 km (180 NM)
SW 280 km (150 NM)

<Forecast for 12 UTC, 5 July>
Intensity Strong
Center position of probability circle N16°35' (16.6°)
E134°20' (134.3°)
Direction and speed of movement WNW 30 km/h (17 kt)
Central pressure 960 hPa
Maximum wind speed near center 40 m/s (80 kt)
Maximum wind gust speed 60 m/s (115 kt)
Radius of probability circle 70 km (40 NM)
Storm warning area ALL 190 km (100 NM)

<Forecast for 00 UTC, 6 July>
Intensity Very strong
Center position of probability circle N18°05' (18.1°)
E131°10' (131.2°)
Direction and speed of movement WNW 30 km/h (17 kt)
Central pressure 950 hPa
Maximum wind speed near center 45 m/s (85 kt)
Maximum wind gust speed 60 m/s (120 kt)
Radius of probability circle 110 km (60 NM)
Storm warning area ALL 240 km (130 NM)

<Forecast for 00 UTC, 7 July>
Intensity Very strong
Center position of probability circle N21°05' (21.1°)
E125°35' (125.6°)
Direction and speed of movement WNW 30 km/h (15 kt)
Central pressure 940 hPa
Maximum wind speed near center 45 m/s (90 kt)
Maximum wind gust speed 65 m/s (130 kt)
Radius of probability circle 200 km (110 NM)
Storm warning area ALL 350 km (190 NM)

<Forecast for 00 UTC, 8 July>
Intensity Very strong
Center position of probability circle N24°05' (24.1°)
E122°25' (122.4°)
Direction and speed of movement NW 20 km/h (11 kt)
Central pressure 935 hPa
Maximum wind speed near center 50 m/s (95 kt)
Maximum wind gust speed 70 m/s (135 kt)
Radius of probability circle 260 km (140 NM)
Storm warning area ALL 430 km (230 NM)

[stormwise]

The further NW this system moves away from the tutt the more favorable the shear has become.
The opposite should now begin to happen i think with increased outflow this may reach super status before rapidly weakening.

[euro6208]

02W NEPARTAK 160705 0000 15.4N 136.7E WPAC 65 974

Here it goes!

[1900hurricane]

Core building looks just about done.

[Alyono]

02W NEPARTAK 160705 0000 15.4N 136.7E WPAC 65 974

Here it goes!

JTWC horribly underestimating this

JMA has 10 min winds higher than JTs 1 minute winds. Their Dvorak is 1 full number too low

[1900hurricane]

So which storm do you think will be the first Cat3 of the NHem this 2016? Will it be Nepartak or Blas? Would be fun to turn this to a betting game.

Gotta go with Nepartak. Despite JTWC's lowballing, as Alyono has already outlined, Nepartak just has a better structure and better environment to work with.

[Yellow Evan]

02W NEPARTAK 160705 0000 15.4N 136.7E WPAC 65 974

Here it goes!

JTWC horribly underestimating this

JMA has 10 min winds higher than JTs 1 minute winds. Their Dvorak is 1 full number too low

Eye seems to be clearing at now as we speak. At least 90 knots IMO.

[1900hurricane]

Himawari-8 loops not from here haven't updated in hours. I wonder why.

[euro6208]

4.5 from JTWC and 5.0 from SSD.

[euro6208]

02W NEPARTAK 160705 0600 16.3N 135.1E WPAC 85 959

Up to 85 knots...

[dexterlabio]

It sucks that Himawari-8 is down when a WPAC typhoon is bombing. That seems to be the case as per the latest JTWC fix.

TPPN10 PGTW 050921

A. TYPHOON 02W (NEPARTAK)

B. 05/0900Z

C. 16.74N

D. 134.35E

E. ONE/HMWRI8

F. T6.0/6.0/D3.0/24HRS STT: D1.5/03HRS

G. IR/EIR

H. REMARKS: 05A/PBO SML EYE/ANMTN. 5NM LG EYE SURROUNDED BY W YIELDS
AN E# AND DT (NO EYE ADJUSTMENT OR BANDING) OF 6.0. PT AGREES. MET
YIELDS A 5.5. DBO DT.

I. ADDITIONAL POSITIONS:

05/0531Z 16.13N 135.15E MMHS


HART

[euro6208]

Wow...WHat a big change from the previous warning, now has a Category 4 monster making landfall over Taiwan and it's still rapidly intensifying...

[euro6208]

WDPN31 PGTW 050900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 02W (NEPARTAK)
WARNING NR 10//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TYPHOON 02W (NEPARTAK), LOCATED APPROXIMATELY 927 NM EAST-
SOUTHEAST OF TAIPEI, TAIWAN, HAS TRACKED WEST-NORTHWESTWARD AT 18
KNOTS OVER THE PAST SIX HOURS. RECENT INFRARED SATELLITE IMAGERY
INDICATES INCREASING ORGANIZATION AND A DEVELOPING EYE, LENDING HIGH
CONFIDENCE TO THE CURRENT POSITION. THE INTENSITY ANALYSIS OF 85
KNOTS IS CONSISTENT WITH RECENT OBJECTIVE, SATELLITE-BASED INTENSITY
CONSENSUS ESTIMATES AND SUBJECTIVE DVORAK VALUES REPORTED BY PGTW,
KNES, AND RJTD. TY 02W IS UNDERGOING A PERIOD OF RAPID
INTENSIFICATION AIDED BY PASSAGE OVER VERY WARM WATER, LOW VERTICAL
WIND SHEAR, AND FAVORABLE OUTFLOW ENHANCED BY AN UPPER-LEVEL TROUGH
TO THE NORTHWEST. TY 02W CONTINUES TO TRACK RAPIDLY NORTHWESTWARD
ALONG THE PERIPHERY OF AN EXTENSIVE DEEP-LAYERED SUBTROPICAL
STEERING RIDGE.
3. FORECAST REASONING.
A. THE FORECAST TRACK HAS BEEN SHIFTED TO THE SOUTH AND WEST,
PARTICULARLY IN THE TAU 48 THROUGH TAU 120 FORECAST PERIOD. THE PEAK
FORECAST INTENSITY HAS INCREASED TO 125 KNOTS, AND A MORE RAPID
WEAKENING TREND IS REFLECTED IN THE EXTENDED FORECAST PERIOD DUE TO
ANTICIPATED LAND INTERACTION AND OTHER ENVIRONMENTAL FACTORS.
B. THE LATEST MID-LEVEL ANALYSIS AND MODEL GUIDANCE PACKAGE
INDICATES A MORE CONTINUOUS STEERING RIDGE EXTENDING FARTHER TO THE
WEST THAN PREVIOUSLY FORECAST. TY 02W IS EXPECTED TO CONTINUE
TRACKING GENERALLY NORTHWESTWARD ALONG THE PERIPHERY OF THIS
STEERING RIDGE OVER THE NEXT 48 HOURS, AND LANDFALL IN TAIWAN IS A
DISTINCT POSSIBILITY. RAPID INTENSIFICATION IS EXPECTED TO CONTINUE
IN THE NEAR-TERM AS MULTIPLE ENVIRONMENTAL FACTORS REMAIN FAVORABLE
FOR FURTHER DEVELOPMENT. ALTHOUGH PEAK INTENSITY IS FORECASTED AT
125 KNOTS, THERE IS POTENTIAL FOR THE SYSTEM TO REACH SUPERTYPHOON
INTENSITY AT SOME POINT BEFORE LANDFALL. BY TAU 72, TY 02W WILL
BEGIN TO ROUND THE STEERING RIDGE PERIPHERY AND WEAKEN A BIT DUE TO
LAND INTERACTION. NUMERICAL MODEL GUIDANCE IS IN GOOD AGREEMENT WITH
THE OVERALL FORECAST SCENARIO WITHIN THE 72 HOUR FORECAST PERIOD,
LENDING HIGH CONFIDENCE TO THAT PORTION OF THE TRACK FORECAST.
C. IN THE EXTENDED PERIOD, TY 02W IS EXPECTED TO ROUND THE
STEERING RIDGE AXIS AND TRACK POLEWARD OVER THE EASTERN COAST OF
CHINA. LAND INTERACTION, INCREASING VERTICAL WIND SHEAR, AND PASSAGE
OVER COOLER WATER WILL LEAD TO STEADY WEAKENING DURING THIS PERIOD.
NUMERICAL MODELS ARE IN GOOD AGREEMENT REGARDING THE OVERALL
FORECAST SCENARIO, BUT THERE IS SIGNIFICANT SPREAD ASSOCIATED WITH
THE LOCATION AND TIMING OF THE TRACK AROUND THE RIDGE PERIPHERY.
GIVEN THIS SPREAD IN THE EXTENDED PERIOD AND THE RECENT FORECAST
SHIFT, THERE IS LOW CONFIDENCE IN THE CURRENT EXTENDED FORECAST
TRACK.//
NNNN

[euro6208]

It sucks that Himawari-8 is down when a WPAC typhoon is bombing. That seems to be the case as per the latest JTWC fix.

TPPN10 PGTW 050921

A. TYPHOON 02W (NEPARTAK)

B. 05/0900Z

C. 16.74N

D. 134.35E

E. ONE/HMWRI8

F. T6.0/6.0/D3.0/24HRS STT: D1.5/03HRS

G. IR/EIR

H. REMARKS: 05A/PBO SML EYE/ANMTN. 5NM LG EYE SURROUNDED BY W YIELDS
AN E# AND DT (NO EYE ADJUSTMENT OR BANDING) OF 6.0. PT AGREES. MET
YIELDS A 5.5. DBO DT.

I. ADDITIONAL POSITIONS:

05/0531Z 16.13N 135.15E MMHS


HART

SSD also at 6.0...

TXPQ28 KNES 050856
TCSWNP

A. 02W (NEPARTAK)

B. 05/0830Z

C. 16.6N

D. 134.5E

E. ONE/XXXX

F. T6.0/6.0/D2.5/24HRS

G. IR/EIR/VIS

H. REMARKS...A LG EYE IS EMBEDDED IN W AND SURROUNDED BY CMG RESULTING
IN A DT OF 6.0. NOTHING WAS ADDED FOR AN EYE ADJUSTMENT. MET IS 5.0 AND
PT IS 5.5. FT IS BASED ON DT.

I. ADDL POSITIONS

NIL


...MICHAEL

[Alyono]

the data is available, not sure why the public satellite sites are not displaying it any longer

[stormwise]

I would go with`100 kts atm=with the 18z forecast.

[1900hurricane]

The JMA Himawari-8 site is still up to date.

http://www.data.jma.go.jp/mscweb/data/himawari/index.html

[stormwise]

http://satview.bom.gov.au/