WPAC: PRAPIROON - Post-Tropical

[euro6208]

WDPN31 PGTW 281500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 09W (NINE)
WARNING NR 01//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL DEPRESSION (TD) 09W (NINE), LOCATED APPROXIMATELY 419 NM
SOUTH-SOUTHEAST OF KADENA AB, HAS TRACKED WESTWARD AT 07 KNOTS
OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY
SHOWS DEEP AND PERSISTENT CONVECTION, MAINLY SOUTH OF THE LOW LEVEL
CIRCULATION CENTER (LLCC) WITH LIMITED CONVECTION NORTH OF THE LLCC.
THE INITIAL POSITION IS BASED ON A 281326Z GMI MICROWAVE SATELLITE
IMAGE SHOWING THE LLCC. THE INITIAL INTENSITY OF 25 KNOTS IS BASED ON
DVORAK INTENSITY ESTIMATES OF T1.5 (25 KNOTS) FROM PGTW AND T1.0 (25
KNOTS) FROM RJTD. ENVIRONMENTAL ANALYSIS SHOWS TD 09W IS EXPERIENCING
FAVORABLE VERTICAL WIND SHEAR (10 TO 15 KNOTS) ALONG WITH MODERATE
POLEWARD AND EQUATORWARD OUTFLOW. SEA SURFACE TEMPERATURES REMAIN
FAVORABLE, RANGING BETWEEN 28 AND 29 DEGREES CELSIUS. TD 09W IS
TRACKING NORTHWESTWARD ALONG THE SOUTHWESTERN EDGE OF THE SUBTROPICAL
RIDGE (STR) WHICH IS LOCATED TO THE NORTHEAST.
3. FORECAST REASONING.
A. THIS IS THE INITIAL PROGNOSTIC REASONING AND SETS THE FORECAST
PHILOSOPHY.
B. TD 09W WILL TRACK NORTHWESTWARD UNDER THE INFLUENCE OF THE
AFOREMENTIONED STR THROUGH TAU 24, THE TRACK WILL THEN BECOME MORE
NORTHWARD. TD 09W WILL CONTINUE TO ENCOUNTER FAVORABLE ENVIRONMENTAL
CONDITIONS WHICH WILL LEAD TO A STEADY INTENSIFICATION. TD 09W WILL
REACH A PEAK INTENSITY OF 50 KNOTS BY TAU 48 AS IT CONTINUES TO ROUND
THE STR. DYNAMIC MODEL GUIDANCE IS IN POOR AGREEMENT, SPECIFICALLY
WITH THE FORWARD SPEED OF THE SYSTEM. THEREFORE, THERE IS LOW
CONFIDENCE IN THIS PORTION OF THE JTWC FORECAST TRACK.
C. BEYOND TAU 72, TD 09W WILL INTERACT WITH A FAST MOVING WEST TO
EAST TROUGH AND WILL CAUSE TD 09W TO RAPIDLY ACCELERATE TO THE NORTH
AND EVENTUALLY NORTHEAST TOWARDS THE KOREAN PENINSULA AS IT BEGINS
EXTRATROPICAL TRANSITION AT TAU 72. EXTRATROPICAL TRANSITION WILL BE
COMPLETE BY TAU 96. DYNAMIC MODEL GUIDANCE IS IN POOR AGREEMENT
REGARDING TRACK SPEED. THERE IS ALSO A WIDE VARIATION IN THE
INTENSITY AND TIMING OF THE EXTRATROPICAL TRANSITION. THEREFORE,
THERE IS LOW CONFIDENCE IN THIS PORTION OF THE JTWC FORECAST TRACK.//
NNNN

[euro6208]

Expected to become a typhoon.

WDPN31 PGTW 282100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 09W (NINE)
WARNING NR 02//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL DEPRESSION 09W (NINE), LOCATED APPROXIMATELY 442 NM
SOUTH-SOUTHEAST OF KADENA AB, HAS TRACKED SOUTHWESTWARD AT 08
KNOTS OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE
IMAGERY SHOWS A LOW LEVEL CIRCULATION COVERED BY FLARING CONVECTION
AND BANDING PRIMARILY TO THE SOUTH AND EAST. THE INITIAL POSITION
IS HEDGED WITH LOW CONFIDENCE BETWEEN THE PGTW AND THE RJTD 18Z FIX
POSITIONS, AS THE LLC IS COVERED. A 281817Z SSMI 85GHZ MICROWAVE
IMAGE SUPPORTS THE GENERAL REGION OF THE INITIAL POSITION UNDER THE
CONVECTION. A 281209Z PARTIAL ASCAT PASS SHOWS AN ELONGATED
CYCLONIC LOW LEVEL CIRCULATION, LENDING UNCERTAINTY TO THE EXACT
POSITION OF THE CENTER. THE INITIAL INTENSITY OF 30 KNOTS IS BASED
ON THE 281209Z PARTIAL ASCAT PASS SHOWING 25-29 KT WIND BARBS TO
THE SOUTHWEST. THE 30 KT INITIAL INTENSITY AGREES WITH THE PGTW 18Z
CURRENT INTENSITY OF T2.0 (30 KTS), AND IS ABOVE THE RJTD CURRENT
INTENSITY ESTIMATE OT T1.5 (25 KTS). ENVIRONMENTAL ANALYSIS SHOWS
TD 09W IS EXPERIENCING FAVORABLE VERTICAL WIND SHEAR (10 TO 15
KNOTS) ALONG WITH EXCELLENT DUAL OUTFLOW ALOFT. SEA SURFACE
TEMPERATURES REMAIN FAVORABLE, RANGING BETWEEN 28 AND 29 DEGREES
CELSIUS. TD 09W HAS RECENTLY JOGGED TO THE SOUTHWEST, ALTHOUGH THE
CONFIDENCE IN THE INITIAL POSITION IS LOW DUE TO THE CDO COVERING
THE LLCC AND THE ELONGATED LLC.
3. FORECAST REASONING.
A. THERE IS NO CHANGE IN THE FORECAST PHILOSOPHY SINCE THE
PREVIOUS PROGNOSTIC REASONING MESSAGE.
B. TD 09W WILL TRACK NORTHWESTWARD ALONG THE SOUTHWESTERN SIDE
OF THE SUBTROPICAL RIDGE TO THE NORTHEAST THROUGH TAU 48, WHEN THE
TRACK WILL BECOME MORE NORTHWARD AFTER IT HAS ROUNDED THE RIDGE.
THOUGH THERE IS DRY AIR TO THE NORTH, TD 09W IS FORECAST TO
STEADILY INTENSIFY UNDER OTHERWISE FAVORABLE ENVIRONMENTAL
CONDITIONS AS A TROPICAL SYSTEM. TD 09W WILL REACH A PEAK
INTENSITY OF 65 KNOTS BY TAU 48, AS AN APPROACHING UPPER LEVEL
TROUGH FROM THE WEST WILL ENHANCE POLEWARD OUTFLOW AS WELL AS BEGIN
ACCELERATING THE SYSTEM TO THE NORTH-NORTHEAST. WIND RADII ARE
FORECAST TO BE ASYMMETRIC, WITH STRONGER WINDS IN THE EASTERN
SECTOR OF THE SYSTEM. THERE ARE SIGNIFICANT DIFFERENCES IN
PREDICTED FORWARD MOTION BETWEEN MODELS, WITH ECMWF AND EGRR MORE
ACCURATELY REFLECTING THE OBSERVED WESTWARD JOG IN RECENT POSITIONS
AND A SLOWER PROPAGATION SPEED, WHILE NAVGEM AND COTC PROPAGATE 09W
MUCH FASTER TO THE NORTH. GFS IS A WESTWARD OUTLIER. THEREFORE,
THERE IS LOW CONFIDENCE IN THIS PORTION OF THE JTWC FORECAST TRACK.
C. BEYOND TAU 72, TD 09W WILL INTERACT WITH THE AFOREMENTIONED
MIDLATITUDE TROUGH AND WILL RAPIDLY ACCELERATE TO THE NORTH AND
EVENTUALLY NORTHEAST TOWARDS THE KOREAN PENINSULA AS IT BEGINS
EXTRATROPICAL TRANSITION AT TAU 72. EXTRATROPICAL TRANSITION WILL
BE COMPLETE BY TAU 96. DYNAMIC MODEL GUIDANCE IS IN POOR AGREEMENT
REGARDING TRACK SPEED, EAST-WEST TRACK SPREAD, THE INTENSITY AND
TIMING OF THE EXTRATROPICAL TRANSITION, AS WELL AS THE DEGREE OF
FRONTAL NATURE AND WIND FIELD EXPANSION OF TD 09W WHEN IT
TRANSITIONS. AS TD 09W IS FORECAST TO TRACK OVERLAND KOREA BETWEEN
TAU 72-96, IT WILL WEAKEN RAPIDLY WHILE COMPLETING EXTRATROPICAL
TRANSITION. THEREFORE, THERE IS LOW CONFIDENCE IN THIS PORTION OF
THE JTWC FORECAST TRACK.//
NNNN

[euro6208]

JTWC at 2.5 and SSD at 2.0.

TPPN10 PGTW 282059

A. TROPICAL DEPRESSION 09W (SE OF OKINAWA)

B. 28/2030Z

C. 19.18N

D. 130.63E

E. FIVE/HMWRI8

F. T2.5/2.5/D1.5/24HRS STT: D0.5/03HRS

G. IR/EIR

H. REMARKS: 38A/PBO SBC/ANMTN. CNVCTN WRAPS .60 ON LOG10 SPIRAL
YIELDING A DT OF 3.0. MET YIELDS A 2.0 WHILE PT YIELDS A 2.5.
DBO PT.

I. ADDITIONAL POSITIONS:
28/1643Z 19.55N 130.58E AMS2
28/1817Z 19.75N 130.73E SSMI


LEMBKE

TXPQ29 KNES 282104
TCSWNP

A. 09W (NONAME)

B. 28/2030Z

C. 20.7N

D. 130.4E

E. THREE/HIMAWARI-8

F. T2.0/2.0/D1.0/24HRS

G. IR/EIR/SWIR/SSMI

H. REMARKS...THIS INTENSITY ESTIMATE WAS DERIVED USING 4 KM IR
DATA. 3.5/10 BANDING WAS INTUITED BY THE 1817Z SSMI IMAGE. THIS YIELDS
A DT OF 2.0. MET AND PT ARE ALSO 2.0. FT IS BASED ON DT.

I. ADDL POSITIONS

28/1817Z 20.5N 130.6E SSMI


...TURK

[euro6208]

UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 8.2.1
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 28 JUN 2018 Time : 211000 UTC
Lat : 19:48:14 N Lon : 130:41:17 E


CI# /Pressure/ Vmax
2.3 /1001.9mb/ 33.0kt


Final T# Adj T# Raw T#
2.3 2.5 2.9

Center Temp : -53.5C Cloud Region Temp : -62.0C

Scene Type : CURVED BAND with 0.71 ARC in LT GRAY

Positioning Method : FORECAST INTERPOLATION

Ocean Basin : WEST PACIFIC
Dvorak CI > MSLP Conversion Used : CKZ Method

Tno/CI Rules : Constraint Limits : 0.7T/6hr
Weakening Flag : OFF
Rapid Dissipation Flag : OFF

C/K/Z MSLP Estimate Inputs :
- Average 34 knot radii : N/A
- Environmental MSLP : 1007mb

Satellite Name : HIM-8
Satellite Viewing Angle : 25.8 degrees

****************************************************

[euro6208]

[euro6208]

EURO and GFS even more stronger. GFS has a North Korea strike.

[euro6208]

UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 8.2.1
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 28 JUN 2018 Time : 234000 UTC
Lat : 19:51:10 N Lon : 130:30:40 E


CI# /Pressure/ Vmax
2.5 /1000.7mb/ 35.0kt


Final T# Adj T# Raw T#
2.5 2.6 2.6

Center Temp : -38.8C Cloud Region Temp : -56.7C

Scene Type : CURVED BAND with 0.58 ARC in LT GRAY
Maximum CURVED BAND with 0.60 ARC in LT GRAY
at Lat: 19:51:00 N Lon: 130:54:36 E

Positioning Method : FORECAST INTERPOLATION

Ocean Basin : WEST PACIFIC
Dvorak CI > MSLP Conversion Used : CKZ Method

Tno/CI Rules : Constraint Limits : NO LIMIT
Weakening Flag : OFF
Rapid Dissipation Flag : OFF

C/K/Z MSLP Estimate Inputs :
- Average 34 knot radii : N/A
- Environmental MSLP : 1007mb

Satellite Name : HIM-8
Satellite Viewing Angle : 26.0 degrees

****************************************************

[Alyono]

TS Prapiroon

[cycloneye]

JMA upgrades to TS PRAPIROON.

TS 1807 (Prapiroon)
Issued at 01:05 UTC, 29 June 2018

<Analysis at 00 UTC, 29 June>
Scale -
Intensity -
Center position N20°00' (20.0°)
E130°10' (130.2°)
Direction and speed of movement W 10 km/h (6 kt)
Central pressure 998 hPa
Maximum sustained wind speed 18 m/s (35 kt)
Maximum wind gust speed 25 m/s (50 kt)
≥ 30 kt wind area ALL 370 km (200 NM)

<Forecast for 00 UTC, 30 June>
Intensity -
Center position of probability circle N21°30' (21.5°)
E129°00' (129.0°)
Direction and speed of movement NW Slow
Central pressure 992 hPa
Maximum wind speed near center 23 m/s (45 kt)
Maximum wind gust speed 35 m/s (65 kt)
Radius of probability circle 90 km (50 NM)

<Forecast for 00 UTC, 1 July>
Intensity -
Center position of probability circle N25°35' (25.6°)
E126°50' (126.8°)
Direction and speed of movement NNW 20 km/h (11 kt)
Central pressure 980 hPa
Maximum wind speed near center 30 m/s (60 kt)
Maximum wind gust speed 45 m/s (85 kt)
Radius of probability circle 200 km (110 NM)
Storm warning area ALL 300 km (160 NM)

<Forecast for 00 UTC, 2 July>
Intensity -
Center position of probability circle N32°50' (32.8°)
E126°05' (126.1°)
Direction and speed of movement N 35 km/h (18 kt)
Central pressure 985 hPa
Maximum wind speed near center 30 m/s (55 kt)
Maximum wind gust speed 40 m/s (80 kt)
Radius of probability circle 410 km (220 NM)
Storm warning area ALL 500 km (270 NM)

[euro6208]

09W NINE 180629 0000 19.6N 130.5E WPAC 35 998

[euro6208]

TPPN10 PGTW 290024

A. TROPICAL DEPRESSION 09W (SE OF OKINAWA)

B. 29/0000Z

C. 19.34N

D. 130.59E

E. FIVE/HMWRI8

F. T2.5/2.5/D1.5/24HRS STT: S0.0/03HRS

G. IR/EIR/VIS/MSI

H. REMARKS: 40A/PBO SBC/ANMTN. CNVCTN WRAPS .60 ON LOG10 SPIRAL
YIELDING A DT OF 3.0. MET YIELDS A 2.0 WHILE PT YIELDS A 2.5.
POSITION IS BASED ON CENTROID DUE TO MULTIPLE VORTICIES. DBO PT.

I. ADDITIONAL POSITIONS:
28/1926Z 19.77N 131.08E SSMS
28/2057Z 19.52N 130.73E SSMS


LEMBKE

[1900hurricane]

With the outflow presentation, I think this one has a better chance to overperform than underperform. The main limiting factor at least in the short term appears to be the possibility of ingesting some of the wedge of dry air to the northwest.

[euro6208]

HWFR takes it to Major.

[cycloneye]

JTWC forecast to be a Typhoon.

[euro6208]

WDPN31 PGTW 290300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 09W (PRAPIROON)
WARNING NR 03//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL STORM 09W (PRAPIROON), LOCATED APPROXIMATELY 440 NM
SOUTH-SOUTHEAST OF KADENA AB, HAS TRACKED WEST-SOUTHWESTWARD AT
04 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY SHOWS SPIRAL BANDING WRAPPING INTO A 100 NM DIAMETER MASS
OF DEEP CONVECTION COVERING UP THE LOW LEVEL CIRCULATION CENTER
(LLCC). THE INITIAL POSITION IS SUPPORTED BY A 282057Z SSMI/S
MICROWAVE IMAGE WITH LOW CONFIDENCE, AS THE LLCC IS OBSCURED BY
CONVECTION. THE INITIAL INTENSITY OF 35 KNOTS IS BASED ON
MULTIAGENCY DVORAK ESTIMATES RANGING FROM T2.0 TO T2.5 (30 TO 35
KTS) HEDGED HIGH DUE TO A 290000Z ADVANCED DVORAK ESTIMATE OF 37
KNOTS. ENVIRONMENTAL ANALYSIS SHOWS TS 09W IS EXPERIENCING SOMEWHAT
FAVORABLE VERTICAL WIND SHEAR (10 TO 15 KNOTS) ALONG WITH GOOD
RADIAL OUTFLOW ALOFT. SEA SURFACE TEMPERATURES REMAIN FAVORABLE,
RANGING BETWEEN 28 AND 29 DEGREES CELSIUS. TS 09W HAS ENTERED A
QUASI-STATIONARY STATE UNDER THE INFLUENCE OF THE STR TO THE
NORTHEAST AND AN EXTENSION OF THE STR TO THE SOUTHWEST.
3. FORECAST REASONING.
A. THERE IS NO CHANGE IN THE FORECAST PHILOSOPHY SINCE THE
PREVIOUS PROGNOSTIC REASONING MESSAGE.
B. BY TAU 12, TS 09W IS EXPECTED TO BREAK FREE OF ITS COMPETING
STEERING INFLUENCES AND BEGIN TO TRACK NORTHWESTWARD ALONG THE
SOUTHWESTERN PERIPHERY OF THE SUBTROPICAL RIDGE TO THE NORTHEAST.
SHORTLY AFTER TAU 48, IT IS EXPECTED TO ROUND THE RIDGE AXIS AND
RECURVE GRADUALLY NORTHWARD. ALTHOUGH DRY AIR TO THE NORTH IS A
LIMITING FACTOR, TS 09W IS FORECAST TO STEADILY INTENSIFY UNDER
OTHERWISE FAVORABLE ENVIRONMENTAL CONDITIONS AS A TROPICAL SYSTEM.
TS 09W IS EXPECTED TO REACH A PEAK INTENSITY OF 70 KNOTS BY TAU 48,
AFTER WHICH AN APPROACHING UPPER LEVEL TROUGH WILL ENHANCE POLEWARD
OUTFLOW AND BEGIN ACCELERATING THE SYSTEM TO THE NORTH-NORTHEAST.
WIND RADII ARE FORECAST TO BE ASYMMETRIC, WITH STRONGER WINDS IN
THE EASTERN SEMI-CIRCLE. MODEL GUIDANCE HAS COME INTO TIGHTER
AGREEMENT; HOWEVER, THERE REMAINS A SIGNIFICANT SPREAD AFTER TAU
48. FOR THIS REASON AS WELL AS THE LACK OF CONFIDENCE IN INITIAL
POSITION, THERE IS LOW CONFIDENCE IN THIS PORTION OF THE JTWC
FORECAST TRACK.
C. BEYOND TAU 72, TS 09W IS EXPECTED TO BEGIN EXTRATROPICAL
TRANSITION AS IT INTERACTS WITH THE AFOREMENTIONED MIDLATITUDE
TROUGH AND RAPIDLY ACCELERATES TO THE NORTH AND THEN NORTHEASTWARD
TOWARDS THE KOREAN PENINSULA. AS TS 09W IS FORECAST TO TRACK
OVERLAND THROUGH KOREA BETWEEN TAU 72-96, IT WILL WEAKEN RAPIDLY
DUE TO FRICTION AND DRY AIR ENTRAINMENT DESPITE THE EXTRATROPICAL
TRANSITION. EXTRATROPICAL TRANSITION WILL BE COMPLETE BY TAU 96.
DYNAMIC MODEL GUIDANCE REMAINS IN POOR AGREEMENT REGARDING TRACK
SPEED, EAST-WEST TRACK SPREAD, AND TIMING OF THE EXTRATROPICAL
TRANSITION. THEREFORE, THERE IS LOW CONFIDENCE IN THIS PORTION OF
THE JTWC FORECAST TRACK.//
NNNN

[euro6208]

A sign of rapid intensification soon?



UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 8.2.1
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 29 JUN 2018 Time : 031000 UTC
Lat : 19:42:12 N Lon : 130:17:26 E


CI# /Pressure/ Vmax
2.8 / 995.3mb/ 41.0kt


Final T# Adj T# Raw T#
2.8 3.0 3.2

Center Temp : -71.0C Cloud Region Temp : -66.5C

Scene Type : UNIFORM CDO CLOUD REGION

Positioning Method : FORECAST INTERPOLATION

Ocean Basin : WEST PACIFIC
Dvorak CI > MSLP Conversion Used : CKZ Method

Tno/CI Rules : Constraint Limits : 0.7T/6hr
Weakening Flag : OFF
Rapid Dissipation Flag : OFF

C/K/Z MSLP Estimate Inputs :
- Average 34 knot radii : 115km
- Environmental MSLP : 1007mb

Satellite Name : HIM-8
Satellite Viewing Angle : 25.9 degrees

****************************************************

[euro6208]

UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 8.2.1
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 29 JUN 2018 Time : 051000 UTC
Lat : 19:44:16 N Lon : 130:11:27 E


CI# /Pressure/ Vmax
3.0 / 993.2mb/ 45.0kt


Final T# Adj T# Raw T#
3.0 3.2 3.2

Center Temp : -64.2C Cloud Region Temp : -61.5C

Scene Type : UNIFORM CDO CLOUD REGION

Positioning Method : FORECAST INTERPOLATION

Ocean Basin : WEST PACIFIC
Dvorak CI > MSLP Conversion Used : CKZ Method

Tno/CI Rules : Constraint Limits : NO LIMIT
Weakening Flag : OFF
Rapid Dissipation Flag : OFF

C/K/Z MSLP Estimate Inputs :
- Average 34 knot radii : 115km
- Environmental MSLP : 1007mb

Satellite Name : HIM-8
Satellite Viewing Angle : 26.0 degrees

****************************************************

[doomhaMwx]

The HWRF model continues to show Prapiroon becoming quite a strong typhoon over the East China Sea.

[euro6208]

Peak now up to 75 knots.

WDPN31 PGTW 290900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 09W (PRAPIROON)
WARNING NR 04//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL STORM (TS) 09W (PRAPIROON), LOCATED APPROXIMATELY 427 NM
SOUTH-SOUTHEAST OF KADENA AB, HAS TRACKED WESTWARD AT 03 KNOTS OVER
THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY SHOWS
THAT SPIRAL BANDING WRAPPING AROUND THE LOW LEVEL CIRCULATION CENTER
(LLCC) CONTINUES TO IMPROVE IN STRUCTURE. THE INITIAL POSITION IS
PLACED WITH LOW CONFIDENCE DUE THE EXTENSIVE CLOUD COVER WHICH IS
OBSCURING THE LLCC. THE INITIAL POSITION IS BASED ON A PARTIAL
290530Z 37GHZ SSMI MICROWAVE IMAGE SHOWING CURVED BANDING. THE
INITIAL INTENSITY OF 40 KNOTS IS HEDGED BETWEEN A 290453Z SATCON
ESTIMATE OF 43 KNOTS, AN ADT ESTIMATE OF T3.1 (47 KNOTS), AND DVORAK
INTENSITY ESTIMATES OF T2.5 (35 KNOTS) FROM PGTW AND T2.0 (30 KNOTS)
FROM RJTD. ENVIRONMENTAL ANALYSIS SHOWS THAT TS 09W IS EXPERIENCING
NEAR RADIAL OUTFLOW AND HAS NEARLY TAPPED INTO THE JET STREAM TO THE
NORTH. THE OUTFLOW PATTERN IS CONDUCIVE FOR CONTINUED DEVELOPMENT.
VERTICAL WIND SHEAR REMAINS FAVORABLE, NEAR 10 TO 15 KNOTS. SEA
SURFACE TEMPERATURES ALSO REMAIN WARM (28 TO 29 DEGREES CELSIUS) AND
WILL SUPPORT ADDITIONAL DEVELOPMENT. TS 09W IS IN A QUASI-STATIONARY
STATE WHILE TRACKING SLOWLY WESTWARD AS IT REMAINS UNDER THE
INFLUENCE OF THE SUBTROPICAL RIDGE (STR) TO THE NORTHEAST AND A
WEAKER STR LOCATED TO THE SOUTHWEST.
3. FORECAST REASONING.
A. THERE IS NO CHANGE IN THE FORECAST PHILOSOPHY SINCE THE
PREVIOUS PROGNOSTIC REASONING MESSAGE.
B. TS 09W WILL DRIFT SLOWLY TO THE NORTHWEST THROUGH TAU 12 AS IT
REMAINS LOCATED BETWEEN THE AFOREMENTIONED STRS. THE STR TO THE
NORTHEAST WILL BECOME THE DOMINATE STEERING FEATURE BY TAU 24 AND
WILL ALLOW TS 09W TO ACCELERATE TOWARD THE NORTHWEST AND EVENTUALLY
TO THE NORTH. AS TS 09W TRACKS NORTHWESTWARD THE UPPER LEVEL OUTFLOW
WILL CONTINUE TO INTERACT WITH THE JET STREAM TO THE NORTH. THIS
ENHANCED OUTFLOW WILL LEAD TO A PEAK INTENSITY OF 75 KNOTS BY TAU 48
WITH THE STRONGEST WINDS REMAINING IN THE RIGHT SEMI-CIRCLE OF THE
SYSTEM. SEA SURFACE TEMPERATURES AND VERTICAL WIND SHEAR WILL ALSO
REMAIN FAVORABLE DURING THIS TIME. TS 09W WILL BEGIN TO INTERACT WITH
THE BAROCLINIC ZONE BY TAU 72 AND WILL BEGIN EXTRATROPICAL TRANSITION
AT THAT TIME WITH AN INTENSITY OF 65 KNOTS. DYNAMIC MODEL GUIDANCE IS
NOW IN FAIRLY GOOD AGREEMENT THROUGH TAU 48. HOWEVER, THERE IS A
WIDER SPREAD IN THE MODEL GUIDANCE AFTER TAU 48. OVERALL, THERE IS
LOW CONFIDENCE IN THIS PORTION OF THE JTWC FORECAST TRACK.
C. BEYOND TAU 72, A WEST TO EAST MOVING TROUGH WILL HELP TO
ACCELERATE TS 09W TOWARD THE NORTH AND EVENTUALLY NORTHEAST. TS 09W
WILL CONTINUE EXTRATROPICAL TRANSITION AND WILL COMPLETE
EXTRATROPICAL TRANSITION BY TAU 96 WITH AN INTENSITY OF 35 KNOTS.
DYNAMIC MODEL GUIDANCE REMAINS IN POOR AGREEMENT REGARDING TRACK
SPEED, EAST-WEST TRACK SPREAD, AND TIMING OF THE EXTRATROPICAL
TRANSITION. THEREFORE, THERE IS LOW CONFIDENCE IN THIS PORTION OF THE
JTWC FORECAST TRACK.//
NNNN

[1900hurricane]

Looks like some dry air did manage to work its way in.