WPAC: TRAMI - Post-Tropical

[Hayabusa]

28W TRAMI 180922 0000 16.6N 140.4E WPAC 50 993

[xtyphooncyclonex]

For the mean time, no more northerly bend at TAU 120. Both the JTWC and JMA agree on track

[euro6208]

WDPN31 PGTW 220300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 28W (TRAMI)
WARNING NR 06//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL STORM (TS) 28W (TRAMI), LOCATED APPROXIMATELY 919NM
SOUTHEAST OF KADENA AB, HAS TRACKED WEST-NORTHWESTWARD AT 11 KNOTS
OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY
(MSI) DEPICTS A COMPACT SYSTEM WITH A PERSISTENT CENTRAL DENSE
OVERCAST, WITH SOME FLARING, OVERSHOOTING TOPS IN VICINITY OF THE
ASSESSED LOW LEVEL CIRCULATION CENTER (LLCC). THE INITIAL POSITION
IS PLACED WITH MEDIUM CONFIDENCE BASED ON ANALYSIS OF THE MSI,
SUPPORTED BY A 212335Z AMSU-B 89 GHZ MICROWAVE IMAGE, WHICH
INDICATED WEAK CONVECTION WRAPPING INTO A COMPACT CORE OF DEEP
CONVECTION CONCENTRATED NEAR THE LLCC. THE INITIAL INTENSITY OF 50
KNOTS IS IN LINE WITH THE DVORAK CURRENT INTENSITY ESTIMATES OF T3.0
(45 KNOTS) FROM KNES AND PGTW, HEDGED SLIGHTLY HIGHER IN LIGHT OF AN
AUTOMATED DVORAK ESTIMATE OF T3.6 (56 KNOTS) AND A SATCON ESTIMATE
OF 56 KNOTS. TS 28W LIES IN A VERY FAVORABLE ENVIRONMENT, WITH LOW
VWS AND HIGH SSTS. THE PRIMARY OUTFLOW CHANNEL IS IN THE PROCESS OF
SHIFTING FROM EASTWARD INTO THE TUTT, TO WESTWARD ALONG THE BASE OF
AN UPPER LEVEL ANTICYCLONE. HENCE, UPPER LEVEL OUTFLOW, WHILE STILL
FAVORABLE, HAS DECREASED OVER THE PAST SIX HOURS LEADING TO A SLOWER
THAN FORECASTED INCREASE IN INTENSITY. TS 28W IS TRACKING WEST-
NORTHWESTWARD UNDER THE INFLUENCE OF THE WEST TO EAST ORIENTATED
SUBTROPICAL RIDGE (STR) LOCATED TO THE NORTH.
3. FORECAST REASONING.
A. THERE IS NO SIGNIFICANT CHANGE TO THE FORECAST PHILOSOPHY FROM
THE PREVIOUS PROGNOSTIC REASONING MESSAGE.
B. TS 28W WILL CONTINUE TO TRACK WEST-NORTHWESTWARD THROUGH TAU
72 UNDER THE STEERING INFLUENCE OF THE PREVIOUSLY MENTIONED STR. VWS
IS FORECAST TO REMAIN LOW, WHILE SSTS REMAIN HIGH (29-30 DEG C)
THROUGH THE FIRST 72 HOURS OF THE FORECAST, SUPPORTING FURTHER
INTENSIFICATION. UPPER LEVEL OUTFLOW WILL BEGIN TO IMPROVE OVER THE
NEXT 6 TO 12 HOURS AS AN UPPER LEVEL POINT SOURCE IS EXPECTED TO
DEVELOP NEAR OR ON TOP OF THE SYSTEM. COMBINED WITH THE OTHER
FAVORABLE ENVIRONMENTAL FACTORS, TS 28W IS FORECAST TO RAPIDLY
INTENSIFY, REACHING AN INTENSITY OF 95 KNOTS WITHIN 48 HOURS. RI-
SPECIFIC MODEL GUIDANCE CONTINUES TO INDICATE A VERY HIGH
PROBABILITY OF RI, LENDING TO HIGH CONFIDENCE IN THIS PORTION OF THE
FORECAST. AFTER TAU 48, THE SYSTEM IS FORECAST TO CONTINUE TO
INTENSIFY, THOUGH AT A SLIGHTLY SLOWER RATE UNDER FAVORABLE
ENVIRONMENTAL CONDITIONS. DYNAMIC MODEL GUIDANCE IS IN GOOD
AGREEMENT WITH A MODEL SPREAD OF 145NM BY TAU 72. JGSM AND CTCX ARE
THE PRIMARY OUTLIERS TO THE SOUTHWEST AND NORTHEAST RESPECTIVELY AND
THE JTWC FORECAST TRACK IS PLACED CLOSE TO THE MULTI-MODEL CONSENSUS
WITH HIGH CONFIDENCE.
C. IN THE LATER TAUS, THE TRACK AND INTENSITY FORECASTS ARE MORE
UNCERTAIN DUE TO LARGE DIFFERENCES IN HOW THE MODELS HANDLE THE
STRENGTH AND ORIENTATION OF THE STEERING PATTERN. BY TAU 72, THE
STEERING RIDGE BEGINS TO MOVE EASTWARD AND ERODE AS A DEEP MID-
LATITUDE TROUGH APPROACHES FROM THE NORTHWEST. BY TAU 96 A LARGE COL
AREA WILL DEVELOP BETWEEN A STR TO THE WEST OVER CHINA AND A STR TO
THE EAST NEAR 160 EAST AND THE TROUGH TO THE NORTH. THE RESULTANT
WEAK STEERING ENVIRONMENT WILL ALLOW TS 28W TO BECOME QUASI-
STATIONARY FROM TAU 96 TO 120. ENVIRONMENTAL CONDITIONS WILL REMAIN
CONDUCIVE FOR INTENSIFICATION THROUGH TAU 96, ALLOWING TS 28W TO
REACH A PEAK INTENSITY OF 135 KNOTS AT TAU 96. AS THE SYSTEM REMAINS
QUASI-STATIONARY FOR AT LEAST 24 HOURS, UPWELLING OF COOLER WATERS
WILL ALLOW FOR WEAKENING THROUGH TAU 120. DYNAMIC MODEL GUIDANCE
AGREEMENT HAS IMPROVED SINCE THE PREVIOUS RUN, BUT IS STILL IN
MODERATELY POOR AGREEMENT, WITH A TRACK SPREAD OF 285NM BY TAU 120.
CTCI AND JGSI REMAIN THE PRIMARY OUTLIERS TO THE NORTHEAST AND
SOUTHWEST, RESPECTIVELY, WITH THE REMAINDER OF THE GUIDANCE SPREAD
FAIRLY EQUALLY BETWEEN THE OUTLIERS. THE OFFICIAL FORECAST TRACK IS
PLACED TO THE NORTH OF THE MULTI-MODEL CONSENSUS, HEDGED SLIGHTLY
MORE TOWARDS THE ECMWF SOLUTION, WITH LOW CONFIDENCE.//
NNNN

[euro6208]

[xtyphooncyclonex]

STS 1824 (Trami)
Issued at 06:45 UTC, 22 September 2018

<Analysis at 06 UTC, 22 September>
Scale -
Intensity -
Center position N16°25' (16.4°)
E139°20' (139.3°)
Direction and speed of movement WNW 20 km/h (12 kt)
Central pressure 990 hPa
Maximum wind speed near center 25 m/s (50 kt)
Maximum wind gust speed 35 m/s (70 kt)
≥ 30 kt wind area NE 390 km (210 NM)
SW 220 km (120 NM)

<Forecast for 18 UTC, 22 September>
Intensity -
Center position of probability circle N16°50' (16.8°)
E136°55' (136.9°)
Direction and speed of movement W 20 km/h (12 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 70 km (40 NM)
Storm warning area ALL 150 km (80 NM)

<Forecast for 06 UTC, 23 September>
Intensity Strong
Center position of probability circle N17°05' (17.1°)
E135°00' (135.0°)
Direction and speed of movement W 20 km/h (10 kt)
Central pressure 965 hPa
Maximum wind speed near center 40 m/s (75 kt)
Maximum wind gust speed 55 m/s (105 kt)
Radius of probability circle 90 km (50 NM)
Storm warning area ALL 200 km (110 NM)

<Forecast for 06 UTC, 24 September>
Intensity Violent
Center position of probability circle N18°50' (18.8°)
E131°10' (131.2°)
Direction and speed of movement WNW 20 km/h (10 kt)
Central pressure 915 hPa
Maximum wind speed near center 55 m/s (105 kt)
Maximum wind gust speed 75 m/s (150 kt)
Radius of probability circle 180 km (95 NM)
Storm warning area ALL 390 km (210 NM)

<Forecast for 06 UTC, 25 September>
Intensity Very strong
Center position of probability circle N19°25' (19.4°)
E129°25' (129.4°)
Direction and speed of movement WNW Slow
Central pressure 925 hPa
Maximum wind speed near center 50 m/s (100 kt)
Maximum wind gust speed 70 m/s (140 kt

[doomhaMwx]

The spread in the model guidance remains pretty large... Northern Luzon to Japan.
Hopefully, the trend does not go closer and closer to Luzon again. We're still recovering from the effects of Mangkhut.

[euro6208]

WDPN31 PGTW 220900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TROPICAL STORM 28W (TRAMI)
WARNING NR 07//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TROPICAL STORM (TS) 28W (TRAMI), LOCATED APPROXIMATELY 866 NM
SOUTHEAST OF KADENA AB, JAPAN, HAS TRACKED WEST-NORTHWESTWARD AT 12
KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY DEPICTS A CONSOLIDATING SYSTEM WITH IMPROVED DEEP CONVECTIVE
BANDING WRAPPING INTO A MORE DEFINED YET RAGGED LOW-LEVEL
CIRCULATION CENTER (LLCC). THIS IMPROVEMENT IS EVIDENT IN A 220633Z
MHS 89GHZ IMAGE, WHICH REVEALS DEEP CONVECTIVE BANDING WRAPPING INTO
A WEAK MICROWAVE EYE FEATURE. CONSEQUENTLY, THERE IS GOOD CONFIDENCE
IN THE INITIAL POSITION. THE INITIAL INTENSITY IS ASSESSED AT 50
KNOTS BASED ON AN AVERAGE OF DVORAK ESTIMATES RANGING FROM T3.0 (45
KNOTS) TO T3.5 (55 KNOTS) WITH A RECENT BYU HIRES ASCAT IMAGE
SHOWING 40 TO 45 KNOTS. UPPER-LEVEL ANALYSIS INDICATES A FAVORABLE
ENVIRONMENT WITH NEAR-RADIAL OUTFLOW, ENHANCED BY A TUTT CELL TO THE
NORTHEAST, AND LOW VERTICAL WIND SHEAR. TS 28W IS TRACKING WEST-
NORTHWESTWARD ALONG THE SOUTHERN PERIPHERY OF A DEEP-LAYERED
SUBTROPICAL RIDGE (STR) ENTRENCHED TO THE NORTH.
3. FORECAST REASONING.
A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE
PREVIOUS PROGNOSTIC REASONING MESSAGE. THE INITIAL 34-KNOT WIND
RADII HAVE BEEN ADJUSTED BASED ON A DETAILED ANALYSIS OF A RECENT
ASCAT IMAGE.
B. TS TRAMI IS FORECAST TO TRACK WEST-NORTHWESTWARD UNDER THE
STEERING INFLUENCE OF THE AFOREMENTIONED STR THROUGH TAU 72.
NUMERICAL MODEL GUIDANCE REMAINS IN TIGHT AGREEMENT WITH A 100NM
SPREAD IN SOLUTIONS AT TAU 72. THE SYSTEM IS EXPECTED TO RAPIDLY
INTENSIFY UNDER FAVORABLE CONDITIONS FROM TAU 12 TO TAU 72 WITH AN
INTENSITY OF 125 KNOTS ANTICIPATED BY TAU 72.
C. AFTER TAU 72, A MIDLATITUDE SHORTWAVE TROUGH WILL DEEPEN OVER
THE EAST CHINA SEA AND WESTERN JAPAN CREATING A BROAD, PERSISTENT
BREAK IN THE STR. THIS WILL RESULT IN A SLIGHT POLEWARD TURN AND
SIGNIFICANT DECREASE IN TRACK SPEEDS AS THE STEERING INFLUENCE
ERODES QUICKLY. NUMERICAL MODEL GUIDANCE INDICATES INCREASING SPREAD
AND GREATER UNCERTAINTY IN THE EXACT FORECAST TRACK WITH A 250-NM
SPREAD IN SOLUTIONS AT TAU 120. FOUR MODELS (NAVGEM, UKMET, AFUM AND
JGSM) DEPICT A WESTWARD TRACK WHILE THE BULK OF THE GUIDANCE SHOWS A
SLOW WEST-NORTHWESTWARD TO NORTHWESTWARD TRACK TOWARD THE BREAK IN
THE STR. THE JTWC OFFICIAL FORECAST FAVORS A SLOW, POLEWARD TRACK AS
THE MORE LIKELY SCENARIO CONSIDERING THE STRENGTH / PROXIMITY OF THE
SHORTWAVE TROUGH AND THE PRESENCE OF A PERSISTENT BREAK IN THE STR.
OVERALL, THERE IS LOW CONFIDENCE IN THE JTWC TRACK DUE TO THE LARGE
SPREAD IN SOLUTIONS AFTER TAU 72. TS TRAMI SHOULD REACH SUPER
TYPHOON INTENSITY IN THE EXTENDED PERIOD.//
NNNN

[euro6208]

TPPN10 PGTW 220936

A. TROPICAL STORM 28W (TRAMI)

B. 22/0900Z

C. 16.75N

D. 138.00E

E. FIVE/HMWRI8

F. T3.5/3.5/D1.0/24HRS STT: D0.5/03HRS

G. IR/EIR

H. REMARKS: 38A/PBO SBC/ANMTN. CNVCTN WRAPS .80 ON LOG10 SPIRAL
YIELDING A DT OF 3.5. MET AND PT AGREE. DBO DT.

I. ADDITIONAL POSITIONS: NONE


LOWE


TXPQ24 KNES 220909
TCSWNP

A. 28W (TRAMI)

B. 22/0830Z

C. 17.1N

D. 138.4E

E. THREE/HIMAWARI-8

F. T3.5/3.5/D1.5/24HRS

G. IR/EIR/SWIR/VIS/AMSR2/AMSU

H. REMARKS...THIS INTENSITY ESTIMATE WAS DERIVED USING 4 KM IR
DATA. RECENT MICROWAVE DATA SHOWS RAPID DEVELOPMENT INTO A CURVED BAND
PATTERN FROM WHAT HAD BEEN A PARTIALLY EXPOSED CENTER IN THE 0046Z
GPM DATA. 10/10 BANDING YIELDS A DT OF 3.5. MET IS 3.5 BASED ON RAPID
DEVELOPMENT OVER THE LAST 24 HOURS. PT IS 3.5 ALSO. FT IS BASED ON DT.

I. ADDL POSITIONS

22/0355Z 16.6N 139.4E AMSR2
22/0633Z 17.0N 138.6E AMSU


...TURK

[euro6208]

CURRENT ESTIMATE
Date (mmddhhmm): 09220632
SATCON: MSLP = 988 hPa MSW = 59 knots
SATCON Member Consensus: 58.0 knots
Pressure -> Wind Using SATCON MSLP: 62 knots
Distance to Outer Closed Isobar Used is 175 nm
Eye Size Correction Used is 0 knots Source: NA

Member Estimates

ADT: 993 hPa 53 knots Scene: CDO Date: SEP220840
CIMSS AMSU: 984 hPa 61 knots Bias Corr: 0 (MW) Date: 09220632
ATMS: 982.1 hPa 64.8 knots Date: 09220410
SSMIS: 979.8 hPa 66.7 knots Date: 09220410
CIRA ATMS: 978 hPa 69 knots Date: 09220410

[Hayabusa]

[euro6208]

Inner core continues to improve and with that, rapid intensification should commence afterwards.

[1900hurricane]

Still a ways to go as far as core structure is concerned.

[NotoSans]

I wonder why JMA has become very aggressive in terms of intensity forecast on these two recent typhoons.

[Hayabusa]

Typhoon Trami



TY 1824 (Trami)
Issued at 18:45 UTC, 22 September 2018

<Analysis at 18 UTC, 22 September>
Scale -
Intensity Strong
Center position N17°05' (17.1°)
E136°10' (136.2°)
Direction and speed of movement W 30 km/h (15 kt)
Central pressure 975 hPa
Maximum wind speed near center 35 m/s (65 kt)
Maximum wind gust speed 50 m/s (95 kt)
≥ 50 kt wind area ALL 80 km (45 NM)
≥ 30 kt wind area NE 390 km (210 NM)
SW 220 km (120 NM)

<Forecast for 06 UTC, 23 September>
Intensity Strong
Center position of probability circle N17°30' (17.5°)
E134°20' (134.3°)
Direction and speed of movement W 15 km/h (9 kt)
Central pressure 965 hPa
Maximum wind speed near center 40 m/s (75 kt)
Maximum wind gust speed 55 m/s (105 kt)
Radius of probability circle 60 km (30 NM)
Storm warning area ALL 170 km (90 NM)

<Forecast for 18 UTC, 23 September>
Intensity Very strong
Center position of probability circle N18°20' (18.3°)
E132°30' (132.5°)
Direction and speed of movement WNW 15 km/h (9 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 90 km (50 NM)
Storm warning area ALL 240 km (130 NM)

<Forecast for 18 UTC, 24 September>
Intensity Very strong
Center position of probability circle N19°30' (19.5°)
E129°40' (129.7°)
Direction and speed of movement WNW 15 km/h (7 kt)
Central pressure 925 hPa
Maximum wind speed near center 50 m/s (100 kt)
Maximum wind gust speed 70 m/s (140 kt)
Radius of probability circle 180 km (95 NM)
Storm warning area ALL 370 km (200 NM)

<Forecast for 18 UTC, 25 September>
Intensity Violent
Center position of probability circle N20°05' (20.1°)
E128°40' (128.7°)
Direction and speed of movement WNW Slow
Central pressure 915 hPa
Maximum wind speed near center 55 m/s (105 kt)
Maximum wind gust speed 75 m/s (150 kt)
Radius of probability circle 240 km (130 NM)
Storm warning area ALL 460 km (250 NM)

[euro6208]

Peaks at 140 knots.

WDPN31 PGTW 222100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/PROGNOSTIC REASONING FOR TYPHOON 28W (TRAMI)
WARNING NR 09//
RMKS//
1. FOR METEOROLOGISTS.
2. 6 HOUR SUMMARY AND ANALYSIS.
TYPHOON (TY) 28W (TRAMI), LOCATED APPROXIMATELY 727 NM SOUTHEAST
OF KADENA AB, OKINAWA, JAPAN, HAS TRACKED WESTWARD AT 15 KNOTS OVER
THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE IMAGERY
DEPICTS AN AREA OF DEEP AND PERSISTENT CONVECTION LOCATED ABOVE THE
LOW LEVEL CIRCULATION CENTER (LLCC) ASSOCIATED WITH TY 28W. THE
INITIAL POSITION IS PLACED WITH HIGH CONFIDENCE AND IS BASED ON A
221608Z 89GHZ AMSR2 MICROWAVE IMAGE SHOWING A FORMATIVE EYE
FEATURE. THE INITIAL INTENSITY OF 65 KNOTS IS BASED ON A DVORAK
INTENSITY ESTIMATE OF T4.0 (65 KNOTS) FROM RJTD. THE INTENSITY IS
HEDGED BETWEEN AN ADT ESTIMATE OF T4.4 (75 KNOTS), A 221641Z SATCON
ESTIMATE OF 78 KNOTS AND A DVORAK INTENSITY ESTIMATE OF T3.5 (55
KNOTS) FROM PGTW. ENVIRONMENTAL ANALYSIS SHOWS THAT TY 28W IS
EXPERIENCING FAVORABLE VERTICAL WIND SHEAR (5 TO 10 KNOTS) ALONG
WITH EXCELLENT RADIAL OUTFLOW WHICH CONTINUES TO TAP INTO THE
TROPICAL UPPER TROPOSPHERIC TROUGH (TUTT) CELL LOCATED TO THE EAST.
SEA SURFACE TEMPERATURES ARE ALSO CONDUCIVE FOR DEVELOPMENT,
BETWEEN 29 TO 30 DEGREES CELSIUS. TY 28W IS TRACKING WESTWARD ALONG
THE SOUTHERN PERIPHERY OF A DEEP-LAYERED SUBTROPICAL RIDGE (STR)
LOCATED TO THE NORTH.
3. FORECAST REASONING.
A. THERE IS NO CHANGE TO THE FORECAST PHILOSOPHY SINCE THE
PREVIOUS PROGNOSTIC REASONING MESSAGE.
B. THROUGH TAU 72, TY 28W WILL TRACK WEST-NORTHWEST WHILE UNDER
THE INFLUENCE OF THE AFOREMENTIONED STR. FAVORABLE ENVIRONMENTAL
CONDITIONS (LOW VERTICAL WIND SHEAR, FAVORABLE OUTFLOW, AND WARM
SEA SURFACE TEMPERATURES) WILL LEAD TO RAPID INTENSIFICATION WHICH
HAS BEEN CAPTURED BY MODEL GUIDANCE. INTENSITY GUIDANCE IS IN GOOD
AGREEMENT. TRACK GUIDANCE IS IN FAIRLY GOOD AGREEMENT THROUGH TAU
48 WITH A SPREAD OF 150NM. HOWEVER, BY TAU 72 THE SPREAD IN MODEL
GUIDANCE INCREASES TO 230NM. THEREFORE, THERE IS LOW CONFIDENCE IN
THIS PORTION OF THE JTWC FORECAST TRACK.
C. AFTER TAU 72, A MIDLATITUDE SHORTWAVE TROUGH WILL DEEPEN OVER
THE EAST CHINA SEA AND WESTERN JAPAN CREATING A BROAD, PERSISTENT
BREAK IN THE STR. STRS TO THE WEST AND NORTHEAST WILL COMPETE TO
BECOME THE DOMINANT STEERING FEATURE. AS A RESULT, TY 28W WILL SLOW
IN FORWARD SPEED AND MAY BECOME QUASI-STATIONARY FOR A SHORT TIME.
MODEL GUIDANCE IS IN POOR AGREEMENT WITH A SIGNIFICANT SPREAD OF
500NM BY TAU 120. MODELS ARE BEGINNING TO SHOW A BIFURCATION WITH
GFS AND COAMPS SHOWING A NORTHWESTWARD TRACK AFTER TAU 72 WHILE
NAVGEM, JGSM, AND AFUM INDICATE A MORE WESTWARD TRACK. THE JTWC
FORECAST TRACK IS PLACED SLIGHTLY SOUTH OF THE MULTI-MODEL
CONSENSUS, FAVORING A MORE WESTWARD TRACK AND NEAR THE ECMWF TRACK.
THEREFORE, THERE IS LOW CONFIDENCE IN THIS PORTION OF THE JTWC
FORECAST TRACK.//
NNNN

[Hayabusa]

OHC during Mangkhut


Trami



While OHC isn't that high now compared to during Mangkhut, I think it's high enough for Trami to intensify to super typhoon

[mrbagyo]

I can see a hint of an eye forming.

[Hayabusa]

28W TRAMI 180923 0000 16.9N 135.1E WPAC 75 978

[Highteeld]

could be a cat 2 in less than 12 hours at this rate

[Highteeld]

Definitely showing signs of an eye