WPAC: LAN - Typhoon

[euro6208]

WDPN32 PGTW 182100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 25W (LAN)
WARNING NR 14//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TYPHOON 25W (LAN), LOCATED APPROXIMATELY 441 NM NORTH-NORTHWEST
OF KAYANGEL, HAS TRACKED NORTH-NORTHWESTWARD AT 08 KNOTS OVER THE
PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY AND A
181536Z METOP-A 89 GHZ GMI IMAGE DEPICTS A BROAD AREA OF DEEP
CONVECTIVE BANDING IN THE SOUTHERN SEMI-CIRCLE WRAPPING INTO A LOW-
LEVEL CIRCULATION CENTER (LLCC). THE INITIAL POSITION IS PLACED WITH
HIGH CONFIDENCE BASED ON THE MICROWAVE IMAGE AND MULTI AGENCY
POSITION FIXES. THE INITIAL INTENSITY IS ASSESSED AT 65 KNOTS BASED
ON DVORAK ESTIMATES FROM PGTW AND RJTD OF T4.0 (65 KNOTS) AND IS
SUPPORTED BY A SATCON ESTIMATE OF 59 KNOTS. ENVIRONMENTAL ANALYSIS
REVEALS THAT THE SYSTEM IS IN AN AREA OF LOW (10-15 KNOTS) VERTICAL
WIND SHEAR (VWS) AND IS TRACKING THROUGH AN AREA OF WARM (30 TO 31
CELSIUS) SEA SURFACE TEMPERATURES (SSTS) AND HIGH OCEAN HEAT
CONTENT. THE SYSTEM HAS A WELL DEFINED POLEWARD OUTFLOW CHANNEL THAT
IS FEEDING INTO A TUTT CELL LOCATED TO THE EAST. CURRENTLY TY 25W IS
TRACKING NORTHWARD ALONG THE WESTERN EXTENT OF A SUBTROPICAL RIDGE
(STR) BUILDING TO THE EAST.
3. FORECAST REASONING.
A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS
PROGNOSTIC REASONING MESSAGE.
B. TY 25W IS FORECAST TO TRACK NORTH-NORTHWESTWARD OVER THE NEXT
24 HOURS UNDER THE INFLUENCE OF THE BUILDING STR LOCATED TO THE
EAST. AFTER TAU 24 THE TRACK WILL TURN DUE NORTH AND THEN BEGIN TO
RECURVE TO THE NORTHEAST AS IT ROUNDS THE NORTHWESTERN EXTENT OF THE
STR. FAVORABLE ENVIRONMENTAL CONDITIONS WILL PERSIST ALLOWING FOR A
RAPID INTENSIFICATION OF TY LAN, REACHING A PEAK INTENSITY OF 125
KNOTS BY TAU 48. DYNAMIC MODEL GUIDANCE IS IN VERY TIGHT AGREEMENT
IN THE TRACK DIRECTION AND SPEED, LENDING HIGH CONFIDENCE IN THIS
PORTION OF THE JTWC TRACK FORECAST.
C. AFTER TAU 72, TY 25W WILL CONTINUE TO TRACK TO THE NORTHEAST
AROUND THE SUB TROPICAL RIDGE AXIS AS IT BEGINS TO INTERACT WITH THE
MID-LATITUDE WESTERLIES. AN APPROACHING MID-LATITUDE TROUGH WILL
INITIALLY ENHANCE OUTFLOW FOR A SHORT PERIOD, THEN LIMIT OUTFLOW
CONTRIBUTING TO A WEAKENING TREND. AS THE SYSTEM INTERACTS WITH THE
MID-LATITUDE TROUGH IT WILL ALSO BEGIN EXTRA-TROPICAL TRANSITION
AROUND TAU 96 AT WHICH TIME IT WILL BEGIN TO GRADUALLY ACCELERATE.
DYNAMIC MODEL GUIDANCE IS IN STRONG AGREEMENT AS TO THE TRACK
DIRECTION, HOWEVER, THE TRACK SPEED VARIES IN THE LATER TAUS LEADING
TO A LARGE SPREAD BY TAU 120. DUE TO THE HIGH DEGREE OF UNCERTAINTY
IN STORM SPEED, THERE IS LOW CONFIDENCE IN THIS PORTION OF THE JTWC
TRACK FORECAST.//
NNNN

[euro6208]

Big difference between the GEFS and GEPS regarding intensity.

[mrbagyo]

Concentric Half Eyewall?
What do we call this? 1/2 ERC.
Lan is a bizarre storm.

[mrbagyo]

looking better now

[euro6208]

25W LAN 171019 0600 16.3N 130.1E WPAC 75 967

[mrbagyo]

Time to tighten up. It now has a decent core

[euro6208]

WDPN32 PGTW 190900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 25W (LAN) WARNING NR 16//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TYPHOON 25W (LAN), LOCATED APPROXIMATELY 625 NM SOUTH-SOUTHEAST OF
KADENA AB, OKINAWA, JAPAN, HAS TRACKED NORTH-NORTHWESTWARD AT 10
KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY (MSI) SHOWS THE DEEP CENTRAL CONVECTION WRAPPED TIGHTER INTO
A LARGE, RAGGED AND PARTLY CLOUD-FILLED EYE. HOWEVER, A SERIES OF
MICROWAVE IMAGES INCLUDING 190448Z ATMS, 190451Z GPM, 190521Z SSMI,
AND A90615Z AMSU, DEPICT A WELL-DEFINED MICROWAVE EYE. THE INITIAL
POSITION IS PLACED WITH HIGH CONFIDENCE BASED ON THE MICROWAVE IMAGES
AND ON THE MSI LOOP. THE INITIAL INTENSITY OF 75 KNOTS IS BASED ON
CONGRUENT AND CLOSELY-CLUSTERED DVORAK FIXES FROM PGTW, KNES, AND
RJTD AND ALSO SUPPORTED BY AUTOMATED OBJECTIVE SATCON ESTIMATES.
ENVIRONMENTAL ANALYSIS REVEALS THAT THE SYSTEM IS IN AN AREA OF LOW
TO MODERATE (10-15 KNOT) VERTICAL WIND SHEAR THAT IS OFFSET BY
EXCELLENT RADIAL OUTFLOW GENERATED BY A POINT SOURCE DIRECTLY
OVERHEAD. ADDITIONALLY, TY 25W IS TRACKING OVER AN AREA OF VERY WARM
(30 TO 31 CELSIUS) SEA SURFACE TEMPERATURES (SSTS) AND HIGH OCEAN
HEAT CONTENT. THE CYCLONE IS TRACKING ALONG THE WESTERN PERIPHERY OF
A DEEP-LAYERED SUBTROPICAL RIDGE (STR) TO THE EAST.
3. FORECAST REASONING.
A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS
PROGNOSTIC REASONING MESSAGE.
B. TY 25W IS FORECAST TO TRACK GENERALLY NORTHWESTWARD OVER THE
NEXT 24-36 HOURS UNDER THE INFLUENCE OF THE STR. AFTERWARD, THE
SYSTEM WILL BEGIN TO ROUND THE WESTERN EDGE OF THE STR. FAVORABLE
ENVIRONMENTAL CONDITIONS WILL PERSIST, AIDED BY INCREASED POLEWARD
OUTFLOW WITH THE INITIAL EXPOSURE TO THE PREVAILING WESTERLIES AS
THE CYCLONE GAINS LATITUDE. THIS WILL ALLOW FOR POSSIBLE RAPID
INTENSIFICATION, REACHING A PEAK INTENSITY OF 120 KNOTS BY TAU 48.
AFTER TAU 48, THE SYSTEM WILL BEGIN TO GRADUALLY WEAKEN AS IT TRACKS
INTO AN AREA OF INCREASING VWS DUE TO INTERACTION WITH THE WESTERLIES
AND AN APPROACHING MID-LATITUDE TROUGH. BY TAU 72, TY 25W WILL BEGIN
EXTRA-TROPICAL TRANSITION (ETT). DYNAMIC MODEL GUIDANCE IS IN TIGHT
AGREEMENT, LENDING HIGH CONFIDENCE IN THIS PORTION OF THE JTWC TRACK
FORECAST.
C. AFTER TAU 72, TY LAN WILL ACCELERATE NORTHEASTWARD ON THE
POLEWARD SIDE OF THE STR AXIS AS IT CONTINUES WITH ITS ETT.
INCREASING VWS AND DECREASING SSTS IN ADDITION TO COOL DRY AIR
ENTRAINMENT IN THE BAROCLINIC ZONE WILL GRADUALLY ERODE THE SYSTEM.
BY TAU 96, TY 25W WILL COOMPLETE ETT BECOMING A COLD CORE LOW WITH AN
EXPANSIVE GALE FORCE WIND FIELD. DYNAMIC MODEL GUIDANCE IS IN STRONG
AGREEMENT AS TO THE TRACK DIRECTION, HOWEVER, THE TRACK SPEED VARIES
IN THE LATER TAUS LEADING TO A LARGE SPREAD BY TAU 120. DUE TO THE
HIGH DEGREE OF UNCERTAINTY IN STORM SPEED, THERE IS LOW CONFIDENCE IN
THIS PORTION OF THE JTWC TRACK FORECAST.//
NNNN

[euro6208]

NAVGEM keeps trending towards Okinawa the past few runs and stronger. Has a massive strike on mainland Japan.

[euro6208]

EURO peaks it at 919 mb east of Okinawa.



GFS trending weaker.

[euro6208]

WDPN32 PGTW 192100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 25W (LAN) WARNING NR 18//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TYPHOON 25W (LAN), LOCATED APPROXIMATELY 523 NM SOUTH-SOUTHEAST
OF KADENA AB, HAS TRACKED NORTHWARD AT 10 KNOTS OVER THE PAST SIX
HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY SHOWS DEEP
BANDING WRAPPING INTO A LARGE, WELL DEFINED LOW LEVEL CIRCULATION
CENTER (LLCC). THE SYSTEM REMAINS VERY BROAD, COVERING OVER 900 NM.
A 191754Z 85 GHZ SSMI IMAGE SHOWS DEEP CONVECTIVE BANDING WRAPPING
INTO A WELL DEFINED MICROWAVE EYE FEATURE. THE INITIAL POSITION IS
PLACED WITH HIGH CONFIDENCE BASED ON THE PREVIOUSLY MENTIONED
MICROWAVE EYE FEATURE. THE INITIAL INTENSITY OF 75 KNOTS IS BASED
ON DVORAK INTENSITY ASSESSMENTS OF T4.5 (77 KNOTS) FROM BOTH PGTW
AND RJTD. ENVIRONMENTAL ANALYSIS INDICATES THAT THE SYSTEM IS IN AN
AREA OF LOW (5-15 KNOT) VERTICAL WIND SHEAR (VWS) THAT IS BEING
OFFSET BY ROBUST RADIAL OUTFLOW. TYPHOON LAN IS TRACKING THOUGH AN
AREA OF VERY WARM (30 TO 31 CELSIUS) SEA SURFACE TEMPERATURES
(SSTS) AND HIGH OCEAN HEAT CONTENT. TY 25W IS TRACKING ALONG THE
WESTERN PERIPHERY OF A DEEP-LAYERED SUBTROPICAL RIDGE (STR) LOCATED
TO THE NORTHEAST.
3. FORECAST REASONING.
A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS
PROGNOSTIC REASONING MESSAGE.
B. TY 25W IS FORECAST TO TRACK NORTHWARD OVER THE NEXT 12-24
HOURS UNDER THE INFLUENCE OF THE STR. AFTER CROSSING THE RIDGE AXIS
AROUND TAU 24, THE SYSTEM WILL BEGIN TO RECURVE BACK TO THE
NORTHEAST. FAVORABLE ENVIRONMENTAL CONDITIONS WILL PERSIST AND
POLEWARD OUTFLOW WILL BE ENHANCED AS THE SYSTEM APPROACHES THE MID-
LATITUDE WESTERLIES. INTERACTION WITH THE WESTERLIES WILL ALLOW FOR
A BRIEF PERIOD OF RAPID INTENSIFICATION, REACHING A PEAK INTENSITY
OF 105 KNOTS AROUND TAU 36. AFTER TAU 48, THE SYSTEM WILL BEGIN TO
GRADUALLY WEAKEN AS VERTICAL WIND SHEAR INCREASES AND THE SYSTEM
BEGINS TO INTERACT WITH AN APPROACHING MID-LATITUDE TROUGH. BY TAU
72, TY 25W WILL BEGIN EXTRA-TROPICAL TRANSITION (ETT). DYNAMIC
MODEL GUIDANCE IS IN STRONG AGREEMENT, LENDING HIGH CONFIDENCE IN
THIS PORTION OF THE JTWC TRACK FORECAST.
C. AFTER TAU 72, TY LAN WILL ACCELERATE NORTHEASTWARD AS IT
BECOMES EMBEDDED IN THE BAROCLINIC ZONE. AROUND TAU 60, THE SYSTEM
IS FORECAST TO MAKE A BRIEF LANDFALL NEAR TOKYO. AFTER EXITING BACK
INTO THE PACIFIC OCEAN, THE SYSTEM IS FORECAST TO CONTINUE TO TRACK
TO THE NORTHEAST AND COMPLETE EXTRA-TROPICAL TRANSITION BY TAU 96,
BECOMING A HURRICANE-FORCE COLD CORE LOW WITH AN EXPANSIVE WIND
FIELD. INCREASING VWS AND THE SYSTEM TRACKING THROUGH AN AREA OF
COOLER (<26 CELSIUS) SEA SURFACE TEMPERATURES WILL CONTINUE TO
WEAKEN THE SYSTEM FOR THE DURATION OF THE FORECAST PERIOD. DYNAMIC
MODEL GUIDANCE IS IN TIGHT AGREEMENT DIRECTION-WISE, HOWEVER,
VARIATIONS IN THE TRACK SPEED AFTER TAU 72 LEAD TO A SIGNIFICANT
SPREAD BY TAU 120. DUE TO THE UNCERTAINTY IN STORM SPEED AND SPREAD
IN THE MODEL GUIDANCE, THERE IS LOW CONFIDENCE IN THIS PORTION OF
THE JTWC TRACK FORECAST.//
NNNN

[sikkar]

Look at that EYE!

[aperson]

Symmetric bands of convection are now firing on both the N and S sides of this system around the large eye structure. Lan seems to finally be getting the symmetry it requires to deepen. I'm curious to see how rapidly it can intensify in these favorable SST and shear conditions given the abnormally large size of the eye structure.

[1900hurricane]

Not looking too bad on visible imagery now.

[euro6208]

85 knots.

WDPN32 PGTW 200300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 25W (LAN) WARNING NR 19//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TYPHOON 25W (LAN), LOCATED APPROXIMATELY 478 NM SOUTH-SOUTHEAST
OF KADENA AB, HAS TRACKED NORTHWARD AT 08 KNOTS OVER THE PAST SIX
HOURS. ANIMATED ENHANCED MULTI-SPECTRAL SATELLITE IMAGERY SHOWS
DEEP CONVECTIVE BANDING WRAPPING INTO A LARGE, CONSOLIDATING, LOW
LEVEL CIRCULATION CENTER (LLCC). THE SYSTEM HAS BEGUN TO
CONSOLIDATE, THOUGH IT REMAINS VERY BROAD, COVERING OVER 850 NM. A
192131Z 91 GHZ SSMIS IMAGE AND A 192206Z 37 GHZ WINDSAT DEPICT DEEP
CONVECTIVE BANDING WRAPPING INTO A WELL DEFINED MICROWAVE EYE
FEATURE. THE INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE BASED
ON EXTRAPOLATION OF THE MICROWAVE EYE FEATURE AND THE PGTW
SATELLITE FIX. THE INITIAL INTENSITY OF 85 KNOTS IS HEDGED ABOVE
DVORAK INTENSITY ASSESSMENTS OF T4.5 (77 KNOTS) FROM BOTH PGTW AND
RJTD AND IS SUPPORTED BY A SATCON ESTIMATE OF 83 KNOTS.
ENVIRONMENTAL ANALYSIS INDICATES THAT THE SYSTEM IS IN AN AREA OF
LOW (5-15 KNOT) VERTICAL WIND SHEAR (VWS) AND IS TRACKING THROUGH
AN AREA OF VERY WARM (30 TO 31 CELSIUS) SEA SURFACE TEMPERATURES.
TYPHOON LAN CURRENTLY HAS AN OUTFLOW CHANNEL THAT EXITS THE
POLEWARD SIDE OF THE STORM, WRAPS AROUND THE EASTERN PERIPHERY, AND
EXTENDS EQUATORWARD. TY 25W IS TRACKING NORTH-NORTHEAST ALONG THE
WESTERN PERIPHERY OF A SUBTROPICAL RIDGE (STR) LOCATED TO THE
NORTHEAST.
3. FORECAST REASONING.
A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS
PROGNOSTIC REASONING MESSAGE.
B. TY 25W IS FORECAST TO TRACK NORTH-NORTHEASTWARD OVER THE NEXT
12-24 HOURS UNDER THE INFLUENCE OF THE STR. AFTER CROSSING THE
RIDGE AXIS AROUND TAU 24, THE SYSTEM WILL BEGIN TO ACCELERATE AND
RECURVE BACK TO THE NORTHEAST ON A TRACK THAT WILL PASS ALONG THE
EAST COAST OF JAPAN. FAVORABLE ENVIRONMENTAL CONDITIONS WILL
PERSIST AND POLEWARD OUTFLOW WILL BE ENHANCED AS THE SYSTEM
APPROACHES THE MID-LATITUDE WESTERLIES. THIS ENHANCED OUTFLOW
WILL ALLOW FOR A PERIOD OF RAPID INTENSIFICATION WITH THE SYSTEM
REACHING A PEAK INTENSITY OF 115 KNOTS AROUND TAU 36. AFTER TAU 36,
THE SYSTEM WILL BEGIN TO GRADUALLY WEAKEN AS IT BEGINS TO INTERACT
WITH A PASSING MID-LATITUDE TROUGH AND BECOMES EMBEDDED IN THE
MID-LATITUDE WESTERLIES, INCREASING VERTICAL WIND SHEAR. THE TROUGH
INTERACTION AND WESTERLIES WILL CAUSE TY 25W TO BEGIN EXTRA-
TROPICAL TRANSITION. DYNAMIC MODEL GUIDANCE IS IN STRONG AGREEMENT,
LENDING HIGH CONFIDENCE IN THIS PORTION OF THE JTWC TRACK FORECAST.
C. AFTER TAU 72, TY LAN WILL CONTINUE TO ACCELERATE
NORTHEASTWARD AS IT BECOMES FULLY EMBEDDED IN THE BAROCLINIC ZONE.
INCREASING VWS AND THE SYSTEM TRACKING THROUGH COOLER (<26 CELSIUS)
SEA SURFACE TEMPERATURES WILL WEAKEN THE SYSTEM FROM TAU 72 THROUGH
THE DURATION OF THE FORECAST PERIOD. SHORTLY AFTER TAU 72, THE
SYSTEM IS FORECAST TO MAKE A BRIEF LANDFALL BETWEEN KYOTO AND
TOKYO. THE SYSTEM?S NORTHEASTERLY TRACK WILL TAKE IT BACK OUT OVER
THE PACIFIC OCEAN SOUTH OF SENDAI. TY LAN WILL CONTINUE TO TRACK TO
THE NORTHEAST AND COMPLETE EXTRA-TROPICAL TRANSITION BY TAU 96,
BECOMING A HURRICANE-FORCE COLD CORE LOW WITH AN EXPANSIVE WIND
FIELD. DYNAMIC MODEL GUIDANCE IS IN TIGHT AGREEMENT FOR THE TRACK
DIRECTION, HOWEVER, VARIATIONS IN THE TRACK SPEED AFTER TAU 48 LEAD
TO A SIGNIFICANT SPREAD IN THE GUIDANCE BY TAU 96. DUE TO THE
UNCERTAINTY IN STORM SPEED IN THE LATER TAUS, THERE IS LOW
CONFIDENCE IN THIS PORTION OF THE JTWC TRACK FORECAST.//
NNNN

[doomhaMwx]

The forecast takes the eye/center very close or possibly even over the Daito islands, located east of Okinawa island,
tomorrow night or on Sunday morning...

[euro6208]

WDPN32 PGTW 200900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 25W (LAN) WARNING NR 20//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TYPHOON 25W (LAN), LOCATED APPROXIMATELY 427 NM SOUTH-SOUTHEAST
OF KADENA AB, OKINAWA, JAPAN, HAS TRACKED NORTHWARD AT 09 KNOTS OVER
THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY SHOWS
EXPANSIVE AND DEEP CONVECTIVE BANDS TIGHTLY WRAPPING INTO A LARGE (55
NM) RAGGED, ALBEIT SYMMETRICAL EYE. THE INITIAL POSITION IS PLACED
WITH HIGH CONFIDENCE BASED THE EYE FEATURE. THE INITIAL INTENSITY OF
90 KNOTS IS BASED ON CONGRUENT AND CLOSELY-CLUSTERED DVORAK FIXES OF
T5.0 FROM PGTW AND RJTD. UPPER LEVEL ANALYSIS INDICATES THAT THE
SYSTEM IS IN AN AREA OF LOW (5-10 KNOT) VERTICAL WIND SHEAR (VWS) AND
EXCELLENT DUAL CHANNEL OUTFLOW. ADDITIONALLY, ALONG-TRACK SEA SURFACE
TEMPERATURES (SSTS) ARE VERY WARM (30 TO 31 CELSIUS). TY 25W IS
TRACKING ALONG THE WESTERN PERIPHERY OF A DEEP-LAYERED SUBTROPICAL
RIDGE (STR) LOCATED TO THE EAST.
3. FORECAST REASONING.
A. NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE PREVIOUS
PROGNOSTIC REASONING MESSAGE.
B. TY 25W WILL BEGIN TO TRACK NORTH-NORTHEASTWARD OVER THE NEXT
48 HOURS UNDER THE INFLUENCE OF THE STR. AFTERWARD, THE SYSTEM WILL
ACCELERATE AS IT RECURVES NORTHEASTWARD ON THE POLEWARD SIDE OF THE
STR AXIS, CROSSING THE KANTO PLAIN OF HONSHU, JAPAN, BEFORE EXITING
BACK INTO THE PACIFIC OCEAN BY TAU 72. FAVORABLE ENVIRONMENTAL
CONDITIONS WILL PERSIST AND POLEWARD OUTFLOW WILL INCREASE AS THE
SYSTEM APPROACHES THE MID-LATITUDE WESTERLIES. THIS INITIAL EXPOSURE
TO THE WESTERLIES WILL ENHANCE OUTFLOW AND ALLOW FOR A PERIOD OF
RAPID INTENSIFICATION, REACHING A PEAK OF 115 KNOTS AROUND TAU 24.
AFTERWARD, THE SYSTEM WILL BEGIN TO GRADUALLY WEAKEN AS IT BEGINS TO
INTERACT WITH A PASSING MID-LATITUDE TROUGH AND BECOMES EMBEDDED IN
THE MID-LATITUDE WESTERLIES, STRONG VWS, COOLER SSTS, AND RUGGED
TERRAIN OF HONSHU. BY TAU 48, TY 25W WILL BEGIN EXTRA-TROPICAL
TRANSITION (ETT) AND BECOME A COLD CORE LOW WITH A VERY WIDE WIND
FIELD BY TAU 72. DYNAMIC MODEL GUIDANCE IS IN TIGHT AGREEMENT,
LENDING HIGH CONFIDENCE IN THIS PORTION OF THE JTWC TRACK FORECAST.
C. AFTER TAU 72, TY LAN WILL CONTINUE TO ACCELERATE NORTHEASTWARD
DEEPER INTO THE BAROCLINIC ZONE. INCREASING VWS, COOLER SSTS, AND DRY
AIR ENTRAINMENT WILL RAPIDLY ERODE THE COLD-CORE SYSTEM DOWN TO 45
KNOTS WITH STILL A RELATIVELY WIDE WIND FIELD. DYNAMIC MODEL GUIDANCE
IS IN TIGHT AGREEMENT FOR THE TRACK DIRECTION, HOWEVER, VARIATIONS IN
THE TRACK SPEED AFTER TAU 48 LEAD TO A SIGNIFICANT SPREAD IN THE
GUIDANCE BY TAU 96. DUE TO THE UNCERTAINTY IN STORM SPEED IN THE
LATER TAUS, THERE IS LOW CONFIDENCE IN THIS PORTION OF THE JTWC TRACK
FORECAST.//
NNNN

[euro6208]

That eye is huge!

[euro6208]

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

----- Current Analysis -----
Date : 20 OCT 2017 Time : 094000 UTC
Lat : 20:02:11 N Lon : 130:16:25 E


CI# /Pressure/ Vmax
5.2 / 960.3mb/ 94.8kt


Final T# Adj T# Raw T#
5.2 5.3 5.6

Estimated radius of max. wind based on IR : 48 km

Center Temp : +6.2C Cloud Region Temp : -71.0C

Scene Type : LARGE EYE

Positioning Method : SPIRAL ANALYSIS

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

Tno/CI Rules : Constraint Limits : 1.7T/6hr
Weakening Flag : OFF
Rapid Dissipation Flag : OFF

C/K/Z MSLP Estimate Inputs :
- Average 34 knot radii : N/A
- Environmental MSLP : 1008mb

Satellite Name : HIM-8
Satellite Viewing Angle : 26.4 degrees

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

[euro6208]

The size is just incredible.

[doomhaMwx]

Category 3...

25W LAN 171020 1200 20.4N 130.2E WPAC 100 950