WPAC: LAN - Post-Tropical

[Hayabusa]

95W INVEST 230805 1800 25.0N 144.0E WPAC 15 1002

[Hayabusa]

12z

[Hayabusa]

18z jma

TROPICAL DEPRESSION 1004 HPA AT 24N 147E NORTH SLOWLY.

[ElectricStorm]

GFS has a strong typhoon moving towards Japan. Euro has a strong TS/Cat 1

[Sciencerocks]

[Sciencerocks]

If this is a depression then 95 and 96L were both tropical cyclones...Vastly more organized.

[Hayabusa]

Up to medium

ABPW10 PGTW 061300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/SIGNIFICANT TROPICAL WEATHER ADVISORY FOR THE WESTERN AND SOUTH
PACIFIC OCEANS REISSUED/061300Z-070600ZAUG2023//
REF/A/MSG/JOINT TYPHOON WRNCEN PEARL HARBOR HI/060752ZAUG2023//
AMPN/REF A IS A TROPICAL CYCLONE WARNING.//
RMKS/
1. WESTERN NORTH PACIFIC AREA (180 TO MALAY PENINSULA):
A. TROPICAL CYCLONE SUMMARY:
(1) AT 06AUG23 0600Z, TROPICAL STORM 06W (KHANUN) WAS LOCATED NEAR
27.8N 130.1E, APPROXIMATELY 319 NM SOUTH OF SASEBO, JAPAN, AND HAD
TRACKED EAST-NORTHEASTWARD AT 06 KNOTS OVER THE PAST SIX HOURS. MAXIMUM
SUSTAINED SURFACE WINDS WERE ESTIMATED AT 55 KNOTS GUSTING TO 70 KNOTS.
SEE REF A (WTPN32 PGTW 060900) FOR FURTHER DETAILS.
(2) NO OTHER TROPICAL CYCLONES.
B. TROPICAL DISTURBANCE SUMMARY:
(1) THE AREA OF CONVECTION (INVEST 95W) PREVIOUSLY LOCATED NEAR
25.7N 145.7E IS NOW LOCATED NEAR 24.8N 145.7E, APPROXIMATELY 238 NM EAST
OF IWO TO, JAPAN. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY AND A
060749Z SSMIS 91GHZ MICROWAVE IMAGE DEPICT A CONSOLIDATING LOW-LEVEL
CIRCULATION WITH CURVED DEEP CONVECTIVE BANDING OVER THE EASTERN
SEMICIRCLE. A RECENT SCATTEROMETER IMAGE SHOWS 15-20 KNOTS TO THE
SOUTHEAST ASSOCIATED WITH THE DEEP CONVECTION AND 10 KNOTS ELSEWHERE.
ENVIRONMENTAL ANALYSIS REMAINS FAVORABLE FOR DEVELOPMENT DUE TO LOW (5-
10 KTS) VWS, WARM (29-30C) SEA SURFACE TEMPERATURES AND GOOD EQUATORWARD
OUTFLOW. GLOBAL MODELS ARE IN GOOD AGREEMENT THAT 95W WILL DRIFT
POLEWARD OVER THE NEXT 48 HOURS WHILE STEADILY CONSOLIDATING AND
INTENSIFYING. MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 15 TO 20
KNOTS. MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1002 MB. THE
POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE WITHIN
THE NEXT 24 HOURS IS UPGRADED TO MEDIUM.

[Hayabusa]

TCFA

WTPN21 PGTW 070300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT (INVEST 95W)//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
A 155 NM RADIUS OF 24.7N 148.7E WITHIN THE NEXT 12 TO 24 HOURS.
AVAILABLE DATA DOES NOT JUSTIFY ISSUANCE OF NUMBERED TROPICAL
CYCLONE WARNINGS AT THIS TIME. WINDS IN THE AREA ARE ESTIMATED TO
BE 18 TO 23 KNOTS. METSAT IMAGERY AT 070000Z INDICATES THAT A
CIRCULATION CENTER IS LOCATED NEAR 24.3N 148.6E. THE SYSTEM IS
MOVING EAST-NORTHEASTWARD AT 11 KNOTS.
2. REMARKS: THE AREA OF CONVECTION (INVEST 95W) PREVIOUSLY LOCATED NEAR
24.8N 145.7E IS NOW LOCATED NEAR 24.3N 148.6E, APPROXIMATELY 400 NM
EAST OF IWO TO, JAPAN. ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI)
AND A 062011Z SSMIS 91 GHZ MICROWAVE SATELLITE PASS REVEAL DEEP
CONVECTIVE BANDS ORGANIZING IN THE SOUTHEASTERN PORTION OF A QUICKLY
CONSOLIDATING, PARTIALLY OBSCURED LOW LEVEL CIRCULATION CENTER
(LLCC). A 070113Z METOP-B SCATTEROMETRY PASS REVEAL AN ELONGATED 20-
25 KTS WIND FIELD EXTENDING ACROSS THE ENTIRE EASTERN SEMICIRCLE,
WRAPPING INTO THE NORTHERN QUADRANT. ENVIRONMENTAL ANALYSIS INDICATES
95W IS IN A FAVORABLE ENVIRONMENT FOR INTENSIFICATION DUE TO WARM
(30-31C) SST, LOW (5-10 KTS) VWS, AND GOOD EQUATORWARD OUTFLOW.
GLOBAL MODELS ARE IN FAIR AGREEMENT THAT 95W QUICKLY INTENSIFY OVER
THE NEXT 24 HOURS, WHILE TURNING BACK TOWARDS THE WEST-NORTHWEST.
MAXIMUM SUSTAINED SURFACE WINDS ARE ESTIMATED AT 18 TO 23 KNOTS.
MINIMUM SEA LEVEL PRESSURE IS ESTIMATED TO BE NEAR 1001 MB. THE
POTENTIAL FOR THE DEVELOPMENT OF A SIGNIFICANT TROPICAL CYCLONE
WITHIN THE NEXT 24 HOURS IS HIGH.
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED BY
080300Z.
//
NNNN

TCW

TD a
Issued at 2023/08/07 01:30 UTC
Analysis at 08/07 00 UTC
Grade TD
Scale -
Intensity -
Center position N24°10′ (24.2°)
E148°50′ (148.8°)
Direction and speed of movement Almost stationary
Central pressure 1002 hPa
Maximum sustained wind speed near center 15 m/s (30 kt)
Maximum wind gust speed 23 m/s (45 kt)
Forecast for 08/08 00 UTC
Grade TS
Intensity -
Center position of probability circle N25°10′ (25.2°)
E148°25′ (148.4°)
Direction and speed of movement NNW Slow
Central pressure 998 hPa
Maximum sustained wind speed near center 18 m/s (35 kt)
Maximum wind gust speed 25 m/s (50 kt)
Radius of probability circle 130 km (70 NM)
Forecast for 08/09 00 UTC
Grade TS
Intensity -
Center position of probability circle N25°20′ (25.3°)
E146°20′ (146.3°)
Direction and speed of movement W Slow
Central pressure 994 hPa
Maximum sustained wind speed near center 20 m/s (40 kt)
Maximum wind gust speed 30 m/s (60 kt)
Radius of probability circle 200 km (110 NM)
Forecast for 08/10 00 UTC
Grade TS
Intensity -
Center position of probability circle N25°40′ (25.7°)
E144°20′ (144.3°)
Direction and speed of movement W Slow
Central pressure 985 hPa
Maximum sustained wind speed near center 23 m/s (45 kt)
Maximum wind gust speed 35 m/s (65 kt)
Radius of probability circle 260 km (140 NM)
Forecast for 08/11 00 UTC
Grade STS
Intensity -
Center position of probability circle N27°35′ (27.6°)
E143°35′ (143.6°)
Direction and speed of movement NNW Slow
Central pressure 980 hPa
Maximum sustained wind speed near center 25 m/s (50 kt)
Maximum wind gust speed 35 m/s (70 kt)
Radius of probability circle 330 km (180 NM)
Forecast for 08/12 00 UTC
Grade STS
Intensity -
Center position of probability circle N29°25′ (29.4°)
E142°50′ (142.8°)
Direction and speed of movement NNW Slow
Central pressure 970 hPa
Maximum sustained wind speed near center 30 m/s (60 kt)
Maximum wind gust speed 45 m/s (85 kt)
Radius of probability circle 440 km (240 NM)
Radius of storm warning area 560 km (300 NM)

[Sciencerocks]

[Sciencerocks]

[cycloneye]

JMA upgrades to TS Lan.

T2307(Lan)
Issued at 2023/08/08 01:20 UTC
Analysis at 08/08 00 UTC
Grade TS
Scale -
Intensity -
Center position N24°30′ (24.5°)
E149°05′ (149.1°)
Direction and speed of movement Almost stationary
Central pressure 1000 hPa
Maximum sustained wind speed near center 18 m/s (35 kt)
Maximum wind gust speed 25 m/s (50 kt)
Radius of 30-kt wind area E390 km (210 NM)
W280 km (150 NM)

[cycloneye]

WDPN31 PGTW 080300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL DEPRESSION 07W (SEVEN) WARNING
NR 002//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
INITIAL POSITION: 24.6N 149.0E
INITIAL INTENSITY: 25 KTS
GEOGRAPHIC REFERENCE: 420 NM EAST OF IWO TO, JAPAN
MOVEMENT PAST 6 HOURS: NORTHWESTWARD AT 04 KTS
SIGNIFICANT WAVE HEIGHT: 12 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) SHOWS A MEDIUM-SIZED
SYSTEM THAT IS SLOWLY CONSOLIDATING EVEN AS THE MAIN CONVECTION
REMAINS SHEARED SOUTHEASTWARD OF AN ELONGATED AND PARTIALLY
EXPOSED LOW LEVEL CIRCULATION (LLC). THE INITIAL POSITION IS
PLACED WITH HIGH CONFIDENCE BASED ON THE PARTIALLY EXPOSED LLC. THE
INITIAL INTENSITY IS ALSO PLACED WITH HIGH CONFIDENCE BASED ON
OVERALL ASSESSMENT OF AGENCY AND AUTOMATED DVORAK ESTIMATES AND
REFLECTS THE SLIGHT 6-HR IMPROVEMENT. ANALYSIS INDICATES A
FAVORABLE ENVIRONMENT WITH WARM SST, AND INCREASING VENTILATION ALOFT,
ONLY TEMPERED BY LOW TO MODERATE VWS.

INITIAL WIND RADII BASIS: NOT APPLICABLE (THERE ARE NO INITIAL WIND
RADII).

CURRENT STEERING MECHANISM: WEAK LOW-LAYER SUBTROPICAL RIDGE TO THE
NORTHEAST.


AGENCY DVORAK AND AUTOMATED FIXES:
PGTW: T2.0 - 30 KTS
RJTD: T2.0 - 30 KTS
KNES: T2.0 - 30 KTS
CIMSS ADT: 29 KTS AT 072340Z

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE
VWS: 10-15 KTS
SST: 30-31 CELSIUS
OUTFLOW: STRONG EQUATORWARD
OTHER FACTORS: MODERATE EASTWARD OUTFLOW INTO A TUTT CELL.

ANALYSIS CONFIDENCE:
INITIAL POSITION: HIGH
INITIAL INTENSITY: HIGH
INITIAL WIND RADII: NOT APPLICABLE

3. FORECAST REASONING.

SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO
THE FORECAST FROM THE PREVIOUS WARNING.

FORECAST DISCUSSION: TD 07W WILL TURN MORE WESTWARD AS THE STR
BUILDS. AFTER TAU 36, THE SYSTEM WILL TRACK MORE NORTHWESTWARD
TOWARD YOKOSUKA AS THE STR RECEDES WITH THE APPROACH OF A
MID-LATITUDE TROUGH FROM THE NORTHWEST. DECREASING VWS AND
INCREASING POLEWARD OUTFLOW WILL FUEL A STEADY INTENSIFICATION TO
75KTS BY TAU 120.


MODEL DISCUSSION: NUMERICAL MODELS ARE IN OVERALL GOOD AGREEMENT
WITH A GRADUAL SPREAD TO 370NM BY TAU 120, LENDING MEDIUM
CONFIDENCE IN THE JTWC TRACK AND INTENSITY FORECASTS.


FORECAST CONFIDENCE:
TRACK 0 - 72 HR: MEDIUM
TRACK 72-120 HR: MEDIUM
INTENSITY 0 - 72 HR: MEDIUM
INTENSITY 72-120 HR: MEDIUM//

[Sciencerocks]

[cycloneye]

WDPN31 PGTW 080900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 07W (LAN) WARNING NR
003//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
INITIAL POSITION: 24.4N 148.5E
INITIAL INTENSITY: 35 KTS
GEOGRAPHIC REFERENCE: 301 NM WEST OF MINAMI TORI SHIMA
MOVEMENT PAST 6 HOURS: WEST-NORTHWESTWARD AT 04 KTS
SIGNIFICANT WAVE HEIGHT: 15 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) DEPICTS A PARTIALLY
OBSCURED LOW LEVEL CIRCULATION CENTER (LLCC) WITH A BULK OF THE
CONVECTION ON THE EASTERN PERIPHERY. A 080521Z SSMIS 91 GHZ
MICROWAVE IMAGE REVEAL DEEP CONVECTIVE BANDS ON THE SOUTHERN AND
EASTERN SEMICIRCLES. THE INITIAL POSITION IS PLACED WITH HIGH
CONFIDENCE BASED ON THE PARTIALLY EXPOSED LLCC. THE INITIAL
INTENSITY IS ALSO PLACED WITH MEDIUM CONFIDENCE BASED ON OVERALL
ASSESSMENT OF AGENCY AND AUTOMATED DVORAK ESTIMATES. ENVIRONMENTAL
ANALYSIS INDICATES 07W IS IN A FAVORABLE ENVIRONMENT FOR
INTENSIFICATION DUE TO WARM (30-31C) SEA SURFACE TEMPERATURES
(SSTS), LOW (5-10 KTS) VERTICAL WIND SHEAR (VWS), AND GOOD
EQUATORWARD OUTFLOW.

INITIAL WIND RADII BASIS: PERSISTENCE

CURRENT STEERING MECHANISM: DEEP-LAYER SUBTROPICAL RIDGE (STR) TO
THE NORTHEAST.

AGENCY DVORAK AND AUTOMATED FIXES:
PGTW: T2.0 - 30 KTS
RJTD: T2.0 - 30 KTS
RCTP: T2.5 - 35 KTS
KNES: T2.0 - 30 KTS
CIMSS SATCON: 34 KTS AT 080238Z
CIMSS ADT: 32 KTS AT 080230Z

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE
VWS: 5-10 KTS
SST: 30-31 CELSIUS
OUTFLOW: STRONG EQUATORWARD

ANALYSIS CONFIDENCE:
INITIAL POSITION: HIGH
INITIAL INTENSITY: MEDIUM
INITIAL WIND RADII: LOW

3. FORECAST REASONING.

SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO
THE FORECAST FROM THE PREVIOUS WARNING.

FORECAST DISCUSSION: TS 07W IS FORECAST TO TRACK ALONG THE OUTER
PERIPHERY OF THE SUBTROPICAL RIDGE (STR) TO THE NORTHEAST, AS THE
SYSTEM CONTINUES TO DO SO THE STR WILL REPOSITION TO A NORTHWEST TO
SOUTHEAST ORIENTATION. AFTER TAU 36, A MID-LATITUDE TROUGH TO THE
NORTH WILL WEAKEN THE STR ALLOWING TS 07W TO ACCELERATE NORTHWESTWARD
TOWARD HONSHU. AS THE SYSTEM TRANSITS NORTHWESTWARD, THE ENVIRONMENTAL
CONDITIONS WILL REMAIN FAVORABLE WITH DECREASING VWS AND INCREASING
POLEWARD OUTFLOW WHICH WILL ALLOW 07W TO STEADILY INTENSIFY TO A
MAXIMUM INTENSITY OF 75 KTS BY TAU 120.

MODEL DISCUSSION: NUMERICAL MODEL GUIDANCE ARE IN OVERALL GOOD
THROUGH TAU 36, WITH ONLY A 83 NM SPREAD IN MODEL TRACK SOLUTIONS.
BY TAU 120 THE MODEL GUIDANCE INCREASES IN UNCERTAINLY WITH A
GRADUAL SPREAD TO 275 NM. THEREFORE, THE JTWC TRACK FORECAST IS
ASSESSED WITH MEDIUM CONFIDENCE TO ACCOUNT FOR THE CROSS TRACK
SPREAD AT TAU 120. INTENSITY GUIDANCE REMAINS MIXED WITH HAFI BEING
AGGRESSIVE WITH A STEADY INTENSIFICATION TO A PEAK OF 85 KNOTS,
WHILE AVNI SHOWS A MORE MODEST INTENSIFICATION WITH A PEAK OF 75
KNOTS. FOR THESE REASONS THE JTWC INTENSITY FORECAST IS ASSESSED
WITH MEDIUM CONFIDENCE AND FOLLOWS CLOSELY TO THE MULTI-MODEL
CONSENSUS.

FORECAST CONFIDENCE:
TRACK 0 - 72 HR: MEDIUM
TRACK 72-120 HR: MEDIUM
INTENSITY 0 - 72 HR: MEDIUM
INTENSITY 72-120 HR: MEDIUM//
NNNN

[Hayabusa]

Euro and latest GFS want this to track over Tokyo, if true would be the first since 2019's Faxai (or Hagibis)
However ensemble spread is large and the multimodel too.

[cycloneye]

WDPN31 PGTW 081500
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 07W (LAN) WARNING NR
004//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
INITIAL POSITION: 24.5N 148.1E
INITIAL INTENSITY: 45 KTS
GEOGRAPHIC REFERENCE: 323 NM WEST OF MINAMI TORI SHIMA
MOVEMENT PAST 6 HOURS: WEST-NORTHWESTWARD AT 04 KTS
SIGNIFICANT WAVE HEIGHT: 17 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY CONTINUES TO
DEPICT A CONSOLIDATING SYSTEM WITH IMPROVED CONVECTIVE BANDING OVER
THE NORTHERN AND EASTERN SEMICIRCLES OBSCURING LOW LEVEL CIRCULATION
CENTER (LLCC). THE INITIAL POSITION IS PLACED WITH MEDIUM
CONFIDENCE BASED ON A GROUPING OF AGENCY POSITION FIXES.
ENVIRONMENTAL CONDITIONS REMAIN FAVORABLE FOR INTENSIFICATION DUE
TO WARM (30-31C) SEA SURFACE TEMPERATURES (SSTS), LOW (5-10 KTS)
VERTICAL WIND SHEAR (VWS), AND GOOD EQUATORWARD OUTFLOW. THE
INITIAL INTENSITY OF 45 KTS IS ASSESSED WITH MEDIUM CONFIDENCE
BASED ON A COMBINATION OF AGENCY DVORAK ESTIMATES FROM PGTW, KNES,
RCTP, RJTD ALONG WITH AUTOMATED DVORAK ESTIMATES. ADDITIONALLY, A
081058Z ASCAT WHICH SHOWS 40-45 KTS OVER THE EASTERN SEMICIRCLE.

INITIAL WIND RADII BASIS: PERSISTENCE

CURRENT STEERING MECHANISM: DEEP-LAYER SUBTROPICAL RIDGE (STR) TO
THE NORTHEAST.

AGENCY DVORAK AND AUTOMATED FIXES:
PGTW: T3.0 - 45 KTS
RJTD: T2.5 - 35 KTS
RCTP: T3.0 - 45 KTS
KNES: T2.5 - 35 KTS
CIMSS ADT: 34 KTS AT 081140Z

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE
VWS: 10-15 KTS
SST: 30-31 CELSIUS
OUTFLOW: STRONG EQUATORWARD

ANALYSIS CONFIDENCE:
INITIAL POSITION: MEDIUM
INITIAL INTENSITY: MEDIUM
INITIAL WIND RADII: LOW

3. FORECAST REASONING.

SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO
THE FORECAST FROM THE PREVIOUS WARNING.

FORECAST DISCUSSION: TS 07W IS FORECAST TO TRACK WEST-NORTHWESTWARD
ALONG THE SOUTHERN AND SOUTHWESTERN PERIPHERIES OF THE STR THROUGH
TAU 36. AFTER TAU 36, 07W WILL SLOW SLIGHTLY AND TURN NORTHWESTWARD
AS A MID-LATITUDE TROUGH TO THE NORTH WILL WEAKEN THE STR. BY TAU
48, THE STR IS EXPECTED TO POSITION TO A NORTH-SOUTH ORIENTATION
SUPPORTING A MORE NORTH-NORTHWESTWARD TRACK. AFTER TAU 72, TS 07W
IS EXPECTED TO ACCELERATE NORTHWESTWARD TOWARD HONSHU THROUGH THE
END OF THE FORECAST. TS 07W WILL INTENSIFY OVER THE NEXT 12 HOURS
AS IT CONSOLIDATES UNDER GENERALLY FAVORABLE CONDITIONS. BY TAU 24,
THE FORECAST CALLS FOR A STEEPER RATE OF INTENSIFICATION AND THE
POSSIBILITY OF RAPID INTENSIFICATION AS POLEWARD OUTFLOW IMPROVES.
AFTER WHICH A PEAK INTENSITY OF 85 KNOTS IS EXPECTED TO OCCUR NEAR
TAU 72.


MODEL DISCUSSION: NUMERICAL MODEL GUIDANCE ARE IN OVERALL GOOD
THROUGH TAU 72, WITH ONLY A 75 NM SPREAD IN MODEL TRACK SOLUTIONS.
BY TAU 120 THE MODEL GUIDANCE INCREASES IN UNCERTAINLY WITH A
GRADUAL SPREAD TO 200 NM. THEREFORE, THE JTWC TRACK FORECAST IS
ASSESSED WITH MEDIUM CONFIDENCE TO ACCOUNT FOR THE CROSS TRACK
SPREAD AT TAU 120. INTENSITY GUIDANCE REMAINS FAIR AGREEMENT AND
SUPPORTS A RAPID INTENSIFICATION PHASE WITH HAFI INDICATING A
STEADY INTENSIFICATION PHASE TO A PEAK OF 95 KNOTS, WHILE AVNI
SHOWS A MORE MODEST INTENSIFICATION WITH A PEAK OF 75 KNOTS.
ADDITIONALLY, RAPID INTENSIFICATION (RI) GUIDANCE IS TRIGGERED
LENDING ADDITIONAL SUPPORT TO THE IMMINENT RI PHASE. FOR THESE
REASONS THE JTWC INTENSITY FORECAST IS ASSESSED WITH MEDIUM
CONFIDENCE AND FOLLOWS CLOSELY TO THE MULTI-MODEL CONSENSUS.

FORECAST CONFIDENCE:
TRACK 0 - 72 HR: HIGH
TRACK 72-120 HR: HIGH
INTENSITY 0 - 72 HR: MEDIUM
INTENSITY 72-120 HR: MEDIUM//
NNNN

[Sciencerocks]

[cycloneye]

WDPN31 PGTW 082100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 07W (LAN) WARNING NR
005//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
INITIAL POSITION: 24.4N 147.6E
INITIAL INTENSITY: 50 KTS
GEOGRAPHIC REFERENCE: 344 NM EAST OF IWO TO, JAPAN
MOVEMENT PAST 6 HOURS: WEST-NORTHWESTWARD AT 06 KTS
SIGNIFICANT WAVE HEIGHT: 22 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED ENHANCED INFRARED (EIR) SATELLITE IMAGERY SHOWS THE SYSTEM
CONTINUED TO CONSOLIDATE AS DEEP CONVECTION HAS NOW WRAPPED ALMOST
COMPLETELY AROUND THE LOW LEVEL CIRCULATION (LLC) FORMING THE EARLY
STAGE OF A BANDING EYE. THE INITIAL POSITION IS PLACED WITH HIGH
CONFIDENCE BASED ON THE FORMATIVE EYE THAT LINED UP WELL WITH A
MICROWAVE EYE FEATURE IN THE 081752Z SSMIS 37GHZ IMAGE. THE
INITIAL INTENSITY IS ALSO PLACED WITH HIGH CONFIDENCE BASED ON THE
HIGH END OF AGENCY AND AUTOMATED DVORAK ESTIMATES AND REFLECTS THE
6-HR IMPROVEMENT. ANALYSIS INDICATES A FAVORABLE ENVIRONMENT WITH
WARM SST, LOW VWS, AND EFFICIENT VENTILATION ALOFT.

INITIAL WIND RADII BASIS: SCATTEROMETER DATA.

CURRENT STEERING MECHANISM: SUBTROPICAL RIDGE (STR) TO THE
NORTHEAST.



AGENCY DVORAK AND AUTOMATED FIXES:
PGTW: T3.0 - 45 KTS
RJTD: T2.5 - 35 KTS
RCTP: T3.0 - 45 KTS
KNES: T3.5 - 55 KTS
CIMSS ADT: 41 KTS AT 081740Z

FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE
VWS: 5-10 KTS
SST: 30-31 CELSIUS
OUTFLOW: STRONG EQUATORWARD
OTHER FACTORS: STRONG EASTWARD OUTFLOW INTO A TUTT CELL.

ANALYSIS CONFIDENCE:
INITIAL POSITION: HIGH
INITIAL INTENSITY: MEDIUM
INITIAL WIND RADII: HIGH

3. FORECAST REASONING.

SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO
THE FORECAST FROM THE PREVIOUS WARNING.

FORECAST DISCUSSION: TS LAN WILL CONTINUE ON ITS CURRENT TRACK
UNDER THE STEERING STR. AFTER TAU 36, IT WILL TRACK MORE
NORTHWESTWARD TOWARD YOKOSUKA, JAPAN, AS THE STR RECEDES WITH THE
APPROACH OF A MID-LATITUDE TROUGH FROM THE NORTHWEST. THE FAVORABLE
ENVIRONMENT WILL FUEL A STEADY INTENSIFICATION TO A PEAK OF 80KTS
BY TAU 96. AFTERWARD, INCREASING VWS AND COOLING SST WILL BEGIN TO
WEAKEN THE SYSTEM, DOWN TO 70KTS BY TAU 120.



MODEL DISCUSSION: NUMERICAL MODELS ARE IN TIGHT AGREEMENT WITH A
GRADUAL AND EVEN SPREAD TO A MERE 105NM BY TAU 120, LENDING HIGH
CONFIDENCE TO THE JTWC TRACK AND INTENSITY FORECASTS.


FORECAST CONFIDENCE:
TRACK 0 - 72 HR: HIGH
TRACK 72-120 HR: HIGH
INTENSITY 0 - 72 HR: HIGH
INTENSITY 72-120 HR: HIGH//
NNNN

[cycloneye]

WDPN31 PGTW 090300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 07W (LAN) WARNING NR
006//
RMKS/
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.

SUMMARY:
INITIAL POSITION: 24.2N 146.9E
INITIAL INTENSITY: 55 KTS
GEOGRAPHIC REFERENCE: 308 NM EAST OF IWO TO
MOVEMENT PAST 6 HOURS: WESTWARD AT 06 KTS
SIGNIFICANT WAVE HEIGHT: 25 FEET

SATELLITE ANALYSIS, INITIAL POSITION AND INTENSITY DISCUSSION:
ANIMATED MULTISPECTRAL SATELLITE IMAGERY (MSI) SHOWS THE SYSTEM
CONTINUED TO CONSOLIDATE AS CENTRAL CONVECTION DEEPENED AND WRAPPED
TIGHTER INTO AN OBSCURED LOW LEVEL CIRCULATION (LLC) WITH A PARTIAL
PINHOLE FORMATIVE EYE. THE INITIAL POSITION IS PLACED WITH HIGH
CONFIDENCE BASED ON THE FORMATIVE EYE THAT LINED UP PERFECTLY WITH
A 082338Z ASCAT BULLSEYE PASS. THE INITIAL INTENSITY IS ALSO PLACED
WITH HIGH CONFIDENCE BASED ON THE HIGH END OF AGENCY AND AUTOMATED
DVORAK ESTIMATES AND THE ASCAT PASS THAT REFLECTS THE 6-HR
IMPROVEMENT. ANALYSIS INDICATES A FAVORABLE ENVIRONMENT WITH WARM
SST, LOW VWS, AND EFFICIENT DUAL OUTFLOW ALOFT.

INITIAL WIND RADII BASIS: SCATTEROMETER DATA.

CURRENT STEERING MECHANISM: SUBTROPICAL RIDGE (STR) TO THE
NORTHEAST.


AGENCY DVORAK AND AUTOMATED FIXES:
PGTW: T3.5 - 55 KTS
RJTD: T2.5 - 35 KTS
RCTP: T3.0 - 45 KTS
KNES: T3.5 - 55 KTS
CIMSS SATCON: 46 KTS AT 081945Z
CIMSS ADT: 41 KTS AT 082340Z
CIMSS D-PRINT: 54 KTS AT 090100Z


FORECASTER ASSESSMENT OF CURRENT ENVIRONMENT: FAVORABLE
VWS: 0-5 KTS
SST: 30-31 CELSIUS
OUTFLOW: STRONG EQUATORWARD
OTHER FACTORS: STRONG EASTWARD OUTFLOW INTO A TUTT CELL.

ANALYSIS CONFIDENCE:
INITIAL POSITION: HIGH
INITIAL INTENSITY: HIGH
INITIAL WIND RADII: HIGH

3. FORECAST REASONING.

SIGNIFICANT FORECAST CHANGES: THERE ARE NO SIGNIFICANT CHANGES TO
THE FORECAST FROM THE PREVIOUS WARNING.

FORECAST DISCUSSION: TS LAN WILL CONTINUE ON A MORE NORTHWESTWARD
TRACK UNDER THE STEERING STR TOWARD YOKOSUKA, JAPAN, AS THE STR
RECEDES WITH THE APPROACH OF A MID-LATITUDE TROUGH FROM THE
NORTHWEST. THE FAVORABLE ENVIRONMENT WILL FUEL A STEADY
INTENSIFICATION TO A PEAK OF 90KTS AT TAUS 36-48. AFTERWARD,
COOLING SST DUE TO UPWELLING IN RELATIVELY SHALLOW WATERS WILL
SLIGHTLY AND GRADUALLY WEAKEN THE SYSTEM, DOWN TO 80KTS BY TAU 120
AS IT APPROACHES SAGAMI BAY.


MODEL DISCUSSION: NUMERICAL MODELS ARE IN TIGHT AGREEMENT WITH A
GRADUAL AND EVEN SPREAD TO A MERE 140NM BY TAU 120, LENDING HIGH
CONFIDENCE TO THE JTWC TRACK FORECAST. GIVEN THE VARIABILITY OF
INTENSITY CHANGE DUE TO UPWELLING, THERE IS ONLY MEDIUM CONFIDENCE
IN THE JTWC INTENSITY FORECAST.


FORECAST CONFIDENCE:
TRACK 0 - 72 HR: HIGH
TRACK 72-120 HR: HIGH
INTENSITY 0 - 72 HR: MEDIUM
INTENSITY 72-120 HR: MEDIUM//
NNNN

[ElectricStorm]

Looks like this could end up being a pretty significant Tokyo threat. Hopefully everyone is prepared.