SIO: CILIDA - Post-Tropical

[WAcyclone]

Cilida is now forecast to reach 140 kt and become Earth's eleventh Category 5 storm of 2018:






Source: https://weather.us

[TyphoonNara]

No longer forcasted to become a cat 5.

[TyphoonNara]

212100Z POSITION NEAR 15.9S 57.8E.
TROPICAL CYCLONE (TC) 07S (CILIDA), LOCATED APPROXIMATELY 271 NM
NORTH OF PORT LOUIS, MAURITIUS, HAS TRACKED SOUTHWARD AT 05 KNOTS
(KTS) OVER THE PAST SIX HOURS. THE INITIAL POSITION IS PLACED WITH
HIGH CONFIDENCE BASED ON A 15 NM WIDE EYE EVIDENT IN ANIMATED
ENHANCED INFRARED SATELLITE IMAGERY. A BULLSEYE 211755Z METOP-B
ASCAT PASS REVEALS A RELATIVELY SMALL, SYMMETRIC WIND FIELD. THE
INITIAL INTENSITY OF 130 KNOTS IS CONSISTENT WITH MULTI-AGENCY
DVORAK CURRENT INTENSITY ESTIMATES RANGING FROM T6.0-T7.0 (115-140
KTS). THE ENVIRONMENT IS FAVORABLE WITH WARM (27-28 CELSIUS) SEA
SURFACE TEMPERATURE (SST), LOW (10-15 KT) VERTICAL WIND SHEAR (VWS),
AND RADIAL OUTFLOW. TC 07S IS TRACKING ALONG THE WESTERN PERIPHERY
OF A SUBTROPICAL RIDGE (STR) TO THE EAST. FOR THE DURATION OF THE
FORECAST, TC 07S WILL ACCELERATE SOUTHWARD TO SOUTHEASTWARD AS IT
TRACKS AROUND THE STR AXIS. TC 07S IS FORECAST TO GRADUALLY WEAKEN
THROUGH TAU 36. AROUND TAU 48, THE CYCLONE WILL BEGIN EXTRATROPICAL
TRANSITION AS IT INTERACTS WITH THE MID-LATITUDE WESTERLIES AND
ENCOUNTERS INCREASING VWS AND COOLING SST. EXTRATROPICAL TRANSITION
WILL BE COMPLETED SOMETIME BETWEEN TAU 72 AND TAU 96. DYNAMIC MODEL
GUIDANCE IS IN TIGHT AGREEMENT WITH A SPREAD OF 140 NM AT TAU 72 AND
210 NM AT TAU 96, LENDING TO HIGH CONFIDENCE IN THE JTWC TRACK
FORECAST. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 211800Z IS 33 FEET.
NEXT WARNINGS AT 220300Z, 220900Z, 221500Z AND 222100Z. REFER TO
TROPICAL CYCLONE 06S (KENANGA) WARNINGS (WTXS31 PGTW) FOR SIX-HOURLY
UPDATES.//

[wxman57]

This is a first. La Reunion has declared Cilida a post-tropical depression after calling it a 70kt TC six hours ago. They have max 10-min winds at 60 kts for this depression. I think they want to take Christmas Day off.



WTIO30 FMEE 241259 RRA
RSMC / TROPICAL CYCLONE CENTER / LA REUNION
TROPICAL CYCLONE FORECAST WARNING (SOUTH-WEST INDIAN OCEAN)
0.A WARNING NUMBER: 26/5/20182019
1.A POST-TROPICAL DEPRESSION 5 (EX-CILIDA)
2.A POSITION 2018/12/24 AT 1200 UTC:
WITHIN 20 NM RADIUS OF POINT 26.4 S / 66.3 E
(TWENTY SIX DECIMAL FOUR DEGREES SOUTH AND SIXTY SIX DECIMAL
THREE DEGREES EAST)
MOVEMENT : SOUTH-EAST 14 KT
3.A DVORAK ANALYSIS: NIL
4.A CENTRAL PRESSURE: 979 HPA
5.A MAX AVERAGE WIND SPEED (10 MN): 60 KT
RADIUS OF MAXIMUM WINDS (RMW) :46 KM
6.A EXTENSION OF WIND BY QUADRANTS (KM):
28 KT NE: 190 SE: 240 SW: 190 NW: 190
34 KT NE: 130 SE: 150 SW: 130 NW: 130
48 KT NE: 90 SE: 110 SW: 90 NW: 90
7.A FIRST CLOSED ISOBAR (PRESSURE / AVERAGE DIAM): 1006 HPA / 700 KM
8.A VERTICAL EXTENSION OF CYCLONE CIRCULATION : DEEP
1.B FORECASTS:
12H: 2018/12/25 00 UTC: 28.7 S / 67.7 E, MAX WIND=055 KT,
POST-TROPICAL DEPRESSION
24H: 2018/12/25 12 UTC: 31.2 S / 68.9 E, MAX WIND=050 KT,
POST-TROPICAL DEPRESSION
36H: 2018/12/26 00 UTC: 34.1 S / 70.4 E, MAX WIND=045 KT,
POST-TROPICAL DEPRESSION
48H: 2018/12/26 12 UTC: 36.3 S / 72.3 E, MAX WIND=040 KT,
POST-TROPICAL DEPRESSION
60H: 2018/12/27 00 UTC: 37.6 S / 74.1 E, MAX WIND=035 KT,
POST-TROPICAL DEPRESSION
72H: 2018/12/27 12 UTC: 38.0 S / 77.1 E, MAX WIND=030 KT,
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