dom

JTWC把預測巔峰強度上調至C2，環境都不錯除了風切有些微強

WTPS31 PGTW 030300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 23P (NIRAN) WARNING NR 009//
RMKS/
1. TROPICAL CYCLONE 23P (NIRAN) WARNING NR 009   
   01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
   MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
   WIND RADII VALID OVER OPEN WATER ONLY
    ---
   WARNING POSITION:
   030000Z --- NEAR 14.7S 148.3E
     MOVEMENT PAST SIX HOURS - 090 DEGREES AT 01 KTS
     POSITION ACCURATE TO WITHIN 050 NM
     POSITION BASED ON CENTER LOCATED BY SATELLITE
   PRESENT WIND DISTRIBUTION:
   MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 064 KT WINDS - 015 NM NORTHEAST QUADRANT
                            010 NM SOUTHEAST QUADRANT
                            010 NM SOUTHWEST QUADRANT
                            015 NM NORTHWEST QUADRANT
   RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
                            035 NM SOUTHEAST QUADRANT
                            025 NM SOUTHWEST QUADRANT
                            030 NM NORTHWEST QUADRANT
   RADIUS OF 034 KT WINDS - 105 NM NORTHEAST QUADRANT
                            070 NM SOUTHEAST QUADRANT
                            060 NM SOUTHWEST QUADRANT
                            105 NM NORTHWEST QUADRANT
   REPEAT POSIT: 14.7S 148.3E
    ---
   FORECASTS:
   12 HRS, VALID AT:
   031200Z --- 14.8S 148.5E
   MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT
                            000 NM SOUTHEAST QUADRANT
                            000 NM SOUTHWEST QUADRANT
                            010 NM NORTHWEST QUADRANT
   RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
                            010 NM SOUTHEAST QUADRANT
                            010 NM SOUTHWEST QUADRANT
                            030 NM NORTHWEST QUADRANT
   RADIUS OF 034 KT WINDS - 160 NM NORTHEAST QUADRANT
                            090 NM SOUTHEAST QUADRANT
                            090 NM SOUTHWEST QUADRANT
                            120 NM NORTHWEST QUADRANT
   VECTOR TO 24 HR POSIT: 115 DEG/ 04 KTS
    ---
   24 HRS, VALID AT:
   040000Z --- 15.1S 149.2E
   MAX SUSTAINED WINDS - 075 KT, GUSTS 090 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 064 KT WINDS - 010 NM NORTHEAST QUADRANT
                            010 NM SOUTHEAST QUADRANT
                            000 NM SOUTHWEST QUADRANT
                            020 NM NORTHWEST QUADRANT
   RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT
                            020 NM SOUTHEAST QUADRANT
                            020 NM SOUTHWEST QUADRANT
                            030 NM NORTHWEST QUADRANT
   RADIUS OF 034 KT WINDS - 190 NM NORTHEAST QUADRANT
                            080 NM SOUTHEAST QUADRANT
                            100 NM SOUTHWEST QUADRANT
                            180 NM NORTHWEST QUADRANT
   VECTOR TO 36 HR POSIT: 110 DEG/ 09 KTS
    ---
   36 HRS, VALID AT:
   041200Z --- 15.8S 151.0E
   MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 064 KT WINDS - 020 NM NORTHEAST QUADRANT
                            010 NM SOUTHEAST QUADRANT
                            010 NM SOUTHWEST QUADRANT
                            020 NM NORTHWEST QUADRANT
   RADIUS OF 050 KT WINDS - 040 NM NORTHEAST QUADRANT
                            020 NM SOUTHEAST QUADRANT
                            030 NM SOUTHWEST QUADRANT
                            050 NM NORTHWEST QUADRANT
   RADIUS OF 034 KT WINDS - 200 NM NORTHEAST QUADRANT
                            140 NM SOUTHEAST QUADRANT
                            140 NM SOUTHWEST QUADRANT
                            190 NM NORTHWEST QUADRANT
   VECTOR TO 48 HR POSIT: 115 DEG/ 14 KTS
    ---
   EXTENDED OUTLOOK:
   48 HRS, VALID AT:
   050000Z --- 16.9S 153.6E
   MAX SUSTAINED WINDS - 090 KT, GUSTS 110 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT
                            010 NM SOUTHEAST QUADRANT
                            020 NM SOUTHWEST QUADRANT
                            030 NM NORTHWEST QUADRANT
   RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT
                            030 NM SOUTHEAST QUADRANT
                            040 NM SOUTHWEST QUADRANT
                            080 NM NORTHWEST QUADRANT
   RADIUS OF 034 KT WINDS - 230 NM NORTHEAST QUADRANT
                            170 NM SOUTHEAST QUADRANT
                            140 NM SOUTHWEST QUADRANT
                            210 NM NORTHWEST QUADRANT
   VECTOR TO 72 HR POSIT: 120 DEG/ 19 KTS
    ---
   72 HRS, VALID AT:
   060000Z --- 20.5S 160.9E
   MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 064 KT WINDS - 050 NM NORTHEAST QUADRANT
                            010 NM SOUTHEAST QUADRANT
                            020 NM SOUTHWEST QUADRANT
                            050 NM NORTHWEST QUADRANT
   RADIUS OF 050 KT WINDS - 080 NM NORTHEAST QUADRANT
                            050 NM SOUTHEAST QUADRANT
                            070 NM SOUTHWEST QUADRANT
                            080 NM NORTHWEST QUADRANT
   RADIUS OF 034 KT WINDS - 310 NM NORTHEAST QUADRANT
                            160 NM SOUTHEAST QUADRANT
                            150 NM SOUTHWEST QUADRANT
                            210 NM NORTHWEST QUADRANT
   VECTOR TO 96 HR POSIT: 120 DEG/ 28 KTS
    ---
   LONG RANGE OUTLOOK:
    ---
   96 HRS, VALID AT:
   070000Z --- 25.8S 171.4E
   MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   BECOMING EXTRATROPICAL
   RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT
                            040 NM SOUTHEAST QUADRANT
                            050 NM SOUTHWEST QUADRANT
                            060 NM NORTHWEST QUADRANT
   RADIUS OF 034 KT WINDS - 200 NM NORTHEAST QUADRANT
                            130 NM SOUTHEAST QUADRANT
                            120 NM SOUTHWEST QUADRANT
                            150 NM NORTHWEST QUADRANT
   VECTOR TO 120 HR POSIT: 125 DEG/ 19 KTS
    ---
   120 HRS, VALID AT:
   080000Z --- 30.3S 178.6E
   MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   EXTRATROPICAL
   RADIUS OF 050 KT WINDS - 060 NM NORTHEAST QUADRANT
                            060 NM SOUTHEAST QUADRANT
                            060 NM SOUTHWEST QUADRANT
                            060 NM NORTHWEST QUADRANT
   RADIUS OF 034 KT WINDS - 120 NM NORTHEAST QUADRANT
                            110 NM SOUTHEAST QUADRANT
                            110 NM SOUTHWEST QUADRANT
                            120 NM NORTHWEST QUADRANT
    ---
REMARKS:
030300Z POSITION NEAR 14.7S 148.3E.
03MAR21. TROPICAL CYCLONE 23P (NIRAN), LOCATED APPROXIMATELY 196
NM NORTHEAST OF CAIRNS, AUSTRALIA, HAS TRACKED EASTWARD AT 01 KNOT
OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY
(MSI) SHOWS CENTRAL DENSE OVERCAST CONTINUING TO DEEPEN AND EXPAND
IN THE CORAL SEA. THE INITIAL POSITION WAS ASSESSED WITH HIGH
CONFIDENCE USING A 022046Z SSMIS 37GHZ AND 91GHZ PASS THAT INDICATES
A MICROWAVE EYE BEGINNING TO FORM. THE INITIAL INTENSITY OF 65KTS IS
BASED WITH HIGH CONFIDENCE AS OVERALL ASSESSMENT FROM MULTIPLE
AGENCY DVORAK INTENSITY ESTIMATES OF T4.0 (65KTS) FROM
PGTW/ABRF/KNES, AND IS SLIGHTLY HIGHER THAN ADVANCED DVORAK
TECHNIQUE (ADT) OF T3.3 (51 KTS) AND THE AFOREMENTIONED MICROWAVE
EYE FEATURE. THE ENVIRONMENT REMAINS OVERALL MARGINALLY FAVORABLE
WITH MODERATE (15-20KT) VERTICAL WIND SHEAR, VERY WARM (29-30C)
SSTS, AND FAIR RADIAL OUTFLOW ALOFT. TC 23P REMAINS QUASI-STATIONARY
AND DRIFTING SLOWLY TO THE EAST-SOUTHEAST AS IT REMAINS IN A COMPLEX
STEERING ENVIRONMENT BETWEEN THE NEAR EQUATORIAL RIDGE (NER) TO THE
NORTHEAST AND THE SUBTROPICAL RIDGE TO THE WEST OVER AUSTRALIA. ONCE
THE NER BECOMES THE DOMINANT STEERING MECHANISM AND NUDGES THE
SYSTEM OUT OF THE AREA IN THE NEXT 12 HOURS EXPECT THE SYSTEM TO
EJECT TO THE SOUTHEAST. THE SYSTEM IS DUE TO MOVE RAPIDLY TO THE
SOUTHEAST AND PASS SOUTH OF NEW CALEDONIA BETWEEN TAU 72 AND 96. THE
ENVIRONMENT WILL BECOME MORE FAVORABLE IN THE NEXT 24 HOURS WITH AN
INCREASE OF POLEWARD OUTFLOW AND PROMOTE AN INCREASE IN
INTENSIFICATION TO A PEAK OF 90KTS BY TAU 48. AFTERWARD, INCREASING
VWS AND COOLING SSTS WILL BEGIN TO ERODE THE CYCLONE DOWN TO 50KTS
BY TAU 120. NEAR TAU 96 THE SYSTEM WILL ENTER THE BAROCLINIC ZONE
AND BEGIN EXTRA-TROPICAL TRANSITION AND COMPLETE TRANSITION BY TAU
120. NUMERICAL MODELS ARE IN GENERAL AGREEMENT WITH THE TRACK
FORECAST WITH SIGNIFICANT VARIATIONS IN ALONG TRACK SPEED IN THE
NEAR-TERM AS NIRAN BEGINS TO SLOWLY PROPAGATE TO THE SOUTHEAST. THE
ALONG TRACK / CROSS TRACK SPREAD IS NOW LESS THAN 200NM BY TAU 48,
HOWEVER, BY TAU 120 ALONG TRACK / CROSS TRACK SPREAD INCREASES TO
WELL OVER 1,300NM, LENDING LOW CONFIDENCE IN THE JTWC TRACK FORECAST
THAT IS LAID CLOSE TO THE MODEL CONSENSUS. MAXIMUM SIGNIFICANT WAVE
HEIGHT AT 030000Z IS 24 FEET. NEXT WARNINGS AT 030900Z, 031500Z,
032100Z AND 040300Z.//
NNNN

老農民版夜神月

JTWC15Z新報大幅提高上望至C3,105KT(上一報09Z時是上望90KT)

老農民版夜神月

BoM18Z定強澳式C2上限60KT,並於新報首度上望澳式C4

SITUATION
At 1800 UTC Tropical Cyclone Niran was centred within 15 nautical miles of
latitude fourteen decimal nine south (14.9S)
longitude one hundred and forty eight decimal one east (148.1E)
Recent movement : slow moving
Maximum winds   : 60 knots
Central pressure: 974 hPa

老農民版夜神月

BoM21Z升格澳式C3,這時的23P.Niran已經底層風眼漂亮開出，高層風眼隱現

老農民版夜神月

JTWC00Z升格C2

23P NIRAN 210304 0000 15.2S 148.7E SHEM 85 962

TPPS10 PGTW 040005

A. TROPICAL CYCLONE 23P (NIRAN)

B. 03/2330Z

C. 15.15S

D. 148.58E

E. THREE/HMWRI8

F. T5.0/5.0/D1.0/24HRS  STT: S0.0/03HRS

G. IR/EIR/VIS/MSI

H. REMARKS: 11A/PBO RAGGED EYE/ANMTN. MG EYE SURROUNDED BY LG
YIELDS AN E# AND DT (NO EYE ADJUSTMENT) OF 5.0. MET AND PT AGREE.
DBO DT.

I. ADDITIONAL POSITIONS: NONE


   RHOADES

老農民版夜神月

風眼開啓，強度穩定增強。BoM,JTWC持續上調上望
00Z報中，BoM上望100節，JTWC更達120節

IDQ20018
TROPICAL CYCLONE TECHNICAL BULLETIN: AUSTRALIA - EASTERN REGION
Issued by AUSTRALIAN BUREAU OF METEOROLOGY TROPICAL CYCLONE WARNING CENTRE
at: 0041 UTC 04/03/2021
Name: Severe Tropical Cyclone Niran
Identifier: 17U
Data At: 0000 UTC
Latitude: 15.1S
Longitude: 148.6E
Location Accuracy: within 10 nm [20 km]
Movement Towards: east southeast [117 deg]
Speed of Movement: 4 knots [8 km/h]
Maximum 10-Minute Wind: 70 knots [130 km/h]
Maximum 3-Second Wind Gust: 100 knots [185 km/h]
Central Pressure: 968 hPa
Radius of 34-knot winds NE quadrant: 150 nm [280 km]
Radius of 34-knot winds SE quadrant: 60 nm [110 km]
Radius of 34-knot winds SW quadrant: 60 nm [110 km]
Radius of 34-knot winds NW quadrant: 90 nm [165 km]
Radius of 48-knot winds NE quadrant: 50 nm [95 km]
Radius of 48-knot winds SE quadrant: 30 nm [55 km]
Radius of 48-knot winds SW quadrant: 30 nm [55 km]
Radius of 48-knot winds NW quadrant: 40 nm [75 km]
Radius of 64-knot winds: 25 nm [45 km]
Radius of Maximum Winds: 15 nm [30 km]
Dvorak Intensity Code: T4.5/4.5/D0.5/24HRS SST:0.0/06HRS
Pressure of outermost isobar: 1000 hPa
Radius of outermost closed isobar: 180 nm [335 km]
FORECAST DATA
Date/Time    : Location    : Loc. Accuracy: Max Wind   : Central Pressure
[UTC]        : degrees     :      nm  [km]: knots[km/h]: hPa
+06:  04/0600: 15.4S 149.5E:     035 [070]:  080  [150]:  968
+12:  04/1200: 15.8S 150.6E:     050 [090]:  090  [165]:  952
+18:  04/1800: 16.4S 152.0E:     055 [105]:  100  [185]:  943
+24:  05/0000: 17.2S 153.7E:     065 [120]:  100  [185]:  944
+36:  05/1200: 19.3S 157.3E:     090 [165]:  090  [165]:  950
+48:  06/0000: 21.4S 161.2E:     125 [230]:  075  [135]:  966
+60:  06/1200: 23.7S 165.8E:     135 [250]:  060  [115]:  973
+72:  07/0000: 26.4S 171.2E:     130 [240]:  055  [100]:  977
+96:  08/0000:             :              :            :     
+120: 09/0000:             :              :            :     

WTPS31 PGTW 040300
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 23P (NIRAN) WARNING NR 013//
RMKS/
1. TROPICAL CYCLONE 23P (NIRAN) WARNING NR 013   
   01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
   MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
   WIND RADII VALID OVER OPEN WATER ONLY
    ---
   WARNING POSITION:
   040000Z --- NEAR 15.2S 148.7E
     MOVEMENT PAST SIX HOURS - 090 DEGREES AT 04 KTS
     POSITION ACCURATE TO WITHIN 020 NM
     POSITION BASED ON EYE FIXED BY A COMBINATION OF
     SATELLITE, RADAR AND SYNOPTIC DATA
   PRESENT WIND DISTRIBUTION:
   MAX SUSTAINED WINDS - 085 KT, GUSTS 105 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 064 KT WINDS - 050 NM NORTHEAST QUADRANT
                            025 NM SOUTHEAST QUADRANT
                            030 NM SOUTHWEST QUADRANT
                            050 NM NORTHWEST QUADRANT
   RADIUS OF 050 KT WINDS - 105 NM NORTHEAST QUADRANT
                            070 NM SOUTHEAST QUADRANT
                            070 NM SOUTHWEST QUADRANT
                            105 NM NORTHWEST QUADRANT
   RADIUS OF 034 KT WINDS - 200 NM NORTHEAST QUADRANT
                            105 NM SOUTHEAST QUADRANT
                            125 NM SOUTHWEST QUADRANT
                            165 NM NORTHWEST QUADRANT
   REPEAT POSIT: 15.2S 148.7E
    ---
   FORECASTS:
   12 HRS, VALID AT:
   041200Z --- 15.9S 150.6E
   MAX SUSTAINED WINDS - 100 KT, GUSTS 125 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
                            020 NM SOUTHEAST QUADRANT
                            020 NM SOUTHWEST QUADRANT
                            030 NM NORTHWEST QUADRANT
   RADIUS OF 050 KT WINDS - 080 NM NORTHEAST QUADRANT
                            040 NM SOUTHEAST QUADRANT
                            040 NM SOUTHWEST QUADRANT
                            080 NM NORTHWEST QUADRANT
   RADIUS OF 034 KT WINDS - 210 NM NORTHEAST QUADRANT
                            150 NM SOUTHEAST QUADRANT
                            130 NM SOUTHWEST QUADRANT
                            200 NM NORTHWEST QUADRANT
   VECTOR TO 24 HR POSIT: 115 DEG/ 16 KTS
    ---
   24 HRS, VALID AT:
   050000Z --- 17.3S 153.5E
   MAX SUSTAINED WINDS - 120 KT, GUSTS 145 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
                            020 NM SOUTHEAST QUADRANT
                            020 NM SOUTHWEST QUADRANT
                            040 NM NORTHWEST QUADRANT
   RADIUS OF 050 KT WINDS - 090 NM NORTHEAST QUADRANT
                            050 NM SOUTHEAST QUADRANT
                            040 NM SOUTHWEST QUADRANT
                            080 NM NORTHWEST QUADRANT
   RADIUS OF 034 KT WINDS - 230 NM NORTHEAST QUADRANT
                            150 NM SOUTHEAST QUADRANT
                            130 NM SOUTHWEST QUADRANT
                            210 NM NORTHWEST QUADRANT
   VECTOR TO 36 HR POSIT: 120 DEG/ 20 KTS
    ---
   36 HRS, VALID AT:
   051200Z --- 19.3S 157.2E
   MAX SUSTAINED WINDS - 115 KT, GUSTS 140 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
                            020 NM SOUTHEAST QUADRANT
                            020 NM SOUTHWEST QUADRANT
                            040 NM NORTHWEST QUADRANT
   RADIUS OF 050 KT WINDS - 090 NM NORTHEAST QUADRANT
                            050 NM SOUTHEAST QUADRANT
                            060 NM SOUTHWEST QUADRANT
                            080 NM NORTHWEST QUADRANT
   RADIUS OF 034 KT WINDS - 260 NM NORTHEAST QUADRANT
                            160 NM SOUTHEAST QUADRANT
                            150 NM SOUTHWEST QUADRANT
                            210 NM NORTHWEST QUADRANT
   VECTOR TO 48 HR POSIT: 120 DEG/ 25 KTS
    ---
   EXTENDED OUTLOOK:
   48 HRS, VALID AT:
   060000Z --- 21.7S 161.8E
   MAX SUSTAINED WINDS - 095 KT, GUSTS 115 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   RADIUS OF 064 KT WINDS - 040 NM NORTHEAST QUADRANT
                            020 NM SOUTHEAST QUADRANT
                            030 NM SOUTHWEST QUADRANT
                            050 NM NORTHWEST QUADRANT
   RADIUS OF 050 KT WINDS - 100 NM NORTHEAST QUADRANT
                            060 NM SOUTHEAST QUADRANT
                            070 NM SOUTHWEST QUADRANT
                            080 NM NORTHWEST QUADRANT
   RADIUS OF 034 KT WINDS - 260 NM NORTHEAST QUADRANT
                            170 NM SOUTHEAST QUADRANT
                            160 NM SOUTHWEST QUADRANT
                            190 NM NORTHWEST QUADRANT
   VECTOR TO 72 HR POSIT: 115 DEG/ 26 KTS
    ---
   72 HRS, VALID AT:
   070000Z --- 25.9S 172.2E
   MAX SUSTAINED WINDS - 070 KT, GUSTS 085 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   BECOMING SUBTROPICAL
   RADIUS OF 064 KT WINDS - 010 NM NORTHEAST QUADRANT
                            000 NM SOUTHEAST QUADRANT
                            020 NM SOUTHWEST QUADRANT
                            030 NM NORTHWEST QUADRANT
   RADIUS OF 050 KT WINDS - 070 NM NORTHEAST QUADRANT
                            040 NM SOUTHEAST QUADRANT
                            060 NM SOUTHWEST QUADRANT
                            070 NM NORTHWEST QUADRANT
   RADIUS OF 034 KT WINDS - 210 NM NORTHEAST QUADRANT
                            160 NM SOUTHEAST QUADRANT
                            140 NM SOUTHWEST QUADRANT
                            170 NM NORTHWEST QUADRANT
   VECTOR TO 96 HR POSIT: 110 DEG/ 26 KTS
    ---
   LONG RANGE OUTLOOK:
    ---
   96 HRS, VALID AT:
   080000Z --- 29.0S 176.7W
   MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
   WIND RADII VALID OVER OPEN WATER ONLY
   SUBTROPICAL
   RADIUS OF 050 KT WINDS - 030 NM NORTHEAST QUADRANT
                            020 NM SOUTHEAST QUADRANT
                            020 NM SOUTHWEST QUADRANT
                            060 NM NORTHWEST QUADRANT
   RADIUS OF 034 KT WINDS - 170 NM NORTHEAST QUADRANT
                            120 NM SOUTHEAST QUADRANT
                            120 NM SOUTHWEST QUADRANT
                            170 NM NORTHWEST QUADRANT
    ---
REMARKS:
040300Z POSITION NEAR 15.4S 149.2E.
04MAR21. TROPICAL CYCLONE (TC) 23P (NIRAN), LOCATED APPROXIMATELY 196
NM EAST-NORTHEAST OF CAIRNS, AUSTRALIA, HAS TRACKED EASTWARD AT
04 KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY (MSI) DEPICTS A FORMATIVE 20-NM EYE WITHIN A SYMMETRIC
CENTRAL DENSE OVERCAST WITH A BANDING FEATURE OVER THE NORTHERN
SEMICIRCLE. MSI SUPPORTS THE INITIAL POSITION AND THE RECENT
EASTWARD TRACK MOTION WITH GOOD CONFIDENCE. ANIMATED RADAR IMAGERY
FROM THE WILLIS ISLAND RADAR REVEALS SPIRAL BANDING WRAPPING INTO A
WELL DEFINED EYEWALL WITH A SMALL BREAK IN THE SOUTH QUADRANT. THE
INITIAL INTENSITY IS ASSESSED AT 85 KNOTS BASED ON DVORAK ESTIMATES
RANGING FROM T4.5 (77 KNOTS) TO T5.0 (90 KNOTS). TC 23P IS LOCATED
ABOUT 98NM NORTHWEST OF WILLIS ISLAND (16.29S 149.97E), WHICH IS
REPORTING 10-MINUTE SUSTAINED WINDS OF 25-30 KTS GUSTING TO 37 KTS.
UPPER-LEVEL ANALYSIS INDICATES A FAVORABLE ENVIRONMENT WITH GOOD
OUTFLOW, LOW VERTICAL WIND SHEAR (VWS) AND WARM SST VALUES (29-30C).
TC 23P IS FORECAST TO ACCELERATE EAST-SOUTHEASTWARD THROUGH THE
FORECAST PERIOD WITHIN THE ENHANCED FLOW BETWEEN A STRONG MAJOR
TROUGH TO THE SOUTH AND THE STEERING RIDGE ENTRENCHED TO THE NORTH
AND NORTHEAST. NUMERICAL MODEL GUIDANCE IS IN FAIR AGREEMENT WITH A
260NM SPREAD IN SOLUTIONS AT TAU 72 LENDING MODERATE CONFIDENCE TO
THE JTWC FORECAST TRACK. BASED ON THE TRIGGERING OF RAPID
INTENSIFICATION PREDICTION AIDS, THE PRESENCE OF A COMPACT CYAN RING
FEATURE IN THE 032031Z SSMIS 37GHZ COLOR COMPOSITE IMAGE, WHICH IS
TYPICALLY INDICATIVE OF IMMINENT RAPID INTENSIFICATION, AND THE
FORMATION OF A SMALL EYE IN EIR, TC 23P IS EXPECTED TO RAPIDLY
INTENSIFY TO A PEAK OF 120 KNOTS BY TAU 24 BUT THIS COULD OCCUR
EARLIER AND PEAK AT A HIGHER INTENSITY. AFTER TAU 36, TC 23P WILL
ENCOUNTER INCREASING VWS ASSOCIATED WITH THE SUBTROPICAL WESTERLIES
AND WILL WEAKEN STEADILY THROUGH THE REMAINDER OF THE PERIOD. NEAR
TAU 72, THE SYSTEM WILL COMMENCE SUBTROPICAL TRANSITION AS IT
BECOMES EMBEDDED WITHIN THE SUBTROPICAL WESTERLIES AND INTERACTS
WITH WEAK BAROCLINICITY ALONG THE NORTHERN EDGE OF THE BAROCLINIC
ZONE. THE SYSTEM SHOULD COMPLETE SUBTROPICAL TRANSITION AS A STORM-
FORCE LOW BY TAU 96. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 040000Z IS
30 FEET. NEXT WARNINGS AT 040900Z, 041500Z, 042100Z AND 050300Z.//
NNNN

dom

Niran也要開眼了
可能成為本年度澳洲地區第二個MH
對上一個是幾天前的Marian

TPPS10 PGTW 040621

A. TROPICAL CYCLONE 23P (NIRAN)

B. 04/0600Z

C. 15.50S

D. 149.43E

E. THREE/HMWRI8

F. T5.5/5.5/D1.0/24HRS STT: D0.5/03HRS

G. IR/EIR/VIS/MSI

H. REMARKS: 11A/PBO RAGGED EYE/ANMTN. OW EYE SURROUNDED BY LG
YIELDS AN E# OF 5.0. ADDED 0.5 EYE ADJUSTMENT FOR B, TO YIELD A
DT OF 5.5.

I. ADDITIONAL POSITIONS: NONE


HEINS

dom

底層眼東南側崩壞，高層風眼填塞，可能是風切較強，早前一度清空至OW
未知情況能否轉好，但還有+12H左右發展空間，JTWC12Z暫將其降格C2下限

23P NIRAN 210304 1200 15.4S 150.4E SHEM 85 964