SPAC: IAN - Tropical Cyclone

[hurricanes1234]

This is one adorable storm! A compact little system with an eye feature forming. How cute!

[stormkite]

UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 8.1.5
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 08 JAN 2014 Time : 223200 UTC
Lat : 16:42:55 S Lon : 176:38:35 W


CI# /Pressure/ Vmax
3.5 / 987.9mb/ 55.0kt

[hurricanes1234]

!!!!!!!! Madness!!!!!!! 85 knots - skipped Category 1 status (SSHS) COMPLETELY!

07P IAN 140109 0000 16.7S 176.7W SHEM 85 959

[stormkite]

[jaguarjace]

RSMC Nadi Tropical Cyclone Warning Centre

TROPICAL CYCLONE FORECAST TRACK MAP
Severe Tropical Cyclone IAN
Issued at 0129 UTC Thursday 9 January 2014.



ORGANISATION HAS SIGNIFICANTLY IMPROVED PAST 12 HOURS. DEEP
CONVECTION PERSISTENT IN THE LAST 15 HOURS. CLOUD TOPS COOLING.
PRIMARY BANDS TIGHTLY WRAPPING AROUND THE LLCC. EYE PARTIALLY
DISCERNIBLE IN VIS IMAGERY. THE SYSTEM REMAINS IN A LOW SHEARED
ENVIRONMENT UNDER AN UPPER DIFFLUENT REGION WITH FAIR OUTFLOW TO THE
EAST AND SOUTH. SST AROUND 29 DEGREES CELCIUS. SYSTEM IS MOVING
EASTWARDS ON THE SOUTHERN PERIPHERY OF THE NEAR EQUATORIAL RIDGE
SITUATED TO THE NORTH OF THE SYSTEM. DVORAK ANALYSIS BASED ON EMBD
CENTRE B SURROUND YIELDING DT OF 5.0, MET=5.0 AND PT=4.5. FT BASED ON
PT THUS, T4.5/4.5/D1.0/24HRS.

THE CONSENSUS OF GLOBAL MODELS AGREE ON A SOUTHEASTWARD MOVEMENT WITH
GRADUAL INTENSIFICATION.

http://www.met.gov.fj/aifs_prods/20032.txt

[stormkite]

07PIAN.85kts 959mb 167S-1767W

[Grifforzer]

http://goo.gl/vPfxPb Tonga special bulletin #12

Severe Tropical Cyclone Ian, Category 4 (960 hPa) located at 16.8S 176.6W or about 185 NM northwest of Va'vau and 220 NM northwest of Ha'apai has 10 minute sustained winds of 90 knots with momentary gusts up to 125 knots. The cyclone is reported as moving southeast at 3 knots.

A Gale Warning is now in force for Va'vau group

A Tropical Cyclone Alert remains in force for Ha'apai group

A Strong Wind Warning remains in force for the Ha'apai group and Niuas

[stormkite]

Certainty has it's mojo going on now. 20140109 0532 SE-PAC 5.0 -16.8 176.4 954 90 IAN

[hurricanes1234]

Magically stopped intensifying - eye is less distinct now even though convection is deeper.

[stormkite]

ZCZC 572
WTPS11 NFFN 090600
TROPICAL DISTURBANCE ADVISORY NUMBER A16 ISSUED FROM RSMC NADI
Jan 09/0835 UTC 2014 UTC.

SEVERE TROPICAL CYCLONE IAN 07F CENTRE 960HPA CAT 4 WAS LOCATED NEAR
16.8S 176.4W AT 090600 UTC. POSITION GOOD BASED ON HR MTSAT EIR
IMAGERY AND PERIPHERAL SURFACE REPORTS. CYCLONE SLOWLY MOVING
EAST-SOUTHEAST AT ABOUT 02 KNOTS. MAXIMUM 10-MINUTE AVERAGE WINDS
NEAR THE CENTRE ESTIMATED AT ABOUT 90 KNOTS.

EXPECT WINDS ABOVE 63 KNOTS WITHIN 20 NAUTICAL MILES OF CENTRE,
ABOVE 47 KNOTS WITHIN 40 NAUTICAL MILES OF CENTRE AND
ABOVE 33 KNOTS WITHIN 70 NAUTICAL MILES OF CENTRE.

ORGANISATION HAS IMPROVED SIGNIFICANTLY PAST 12 HOURS. DEEP
CONVECTION PERSISTENT. CLOUD TOPS COOLING PAST 6 HOURS. EYE
DISCERNIBLE IN VIS/IR IMAGERY BUT IS PARTIALLY CLOUD FILLED. THE
SYSTEM REMAINS IN A LOW SHEARED ENVIRONMENT UNDER AN UPPER RIDGE WITH
FAIR OUTFLOW TO THE EAST AND SOUTH. SST AROUND 29 DEGREES CELCIUS.
SYSTEM CURRENTLY LOCATED IN A WEAK STEERING ENVIRONMENT, BETWEEN A
SUB-TROPICAL RIDGE LOCATED TO THE SOUTH AND NEAR-EQUATORIAL RIDGE
LOCATED TO THE NORTH OF THE SYSTEM. BUT THE SUB-TROPICAL RIDGE IS
SHOWING SIGNS OF WEAKENING. DVORAK ANALYSIS BASED ON EYE PATTERN WITH
B EYE AND W SURROUND, SUBTRACTING 0.5 FOR EYE ADJUSTMENT YIELDS DT OF
5.5, MET=5.5 AND PT=5.5. FT BASED ON DT THUS, T5.5/5.5/D2.0/24HRS.

THE CONSENSUS OF GLOBAL MODELS AGREE ON A SOUTHEASTWARD MOVEMENT WITH
GRADUAL INTENSIFICATION.

FORECASTS :
AT 12 HRS VALID AT 091800 UTC 17.3S 175.6W MOV SE AT 05 KT WITH 90 KT
CLOSE TO CENTRE
AT 24 HRS VALID AT 100600 UTC 18.1S 174.8W MOV SE AT 06 KT WITH 90 KT
CLOSE TO CENTRE

OUTLOOK :
AT 36 HRS VALID AT 101800 UTC 19.2S 174.0W MOV SE AT 07 KT WITH 90 KT
CLOSE TO CENTRE
AT 48 HRS VALID AT 110600 UTC 20.6S 173.3W MOV SSE AT 07 KT WITH 80
KT CLOSE TO CENTRE

THE NEXT TROPICAL DISTURBANCE ADVISORY ON SEVERE TROPICAL CYCLONE IAN
WILL BE ISSUED AROUND 091400 UTC.





NNNN


T5.5 = 102 KNOTS Cat 3

[stormkite]

Magically stopped intensifying - eye is less distinct now even though convection is deeper.

Yeah lots of oddities with this system

[euro6208]

WOW! this is such a cute little cyclone with a distinct eye earlier. truly impressive.

85 knots...

REMARKS:
090900Z POSITION NEAR 16.9S 176.4W.
TROPICAL CYCLONE 07P (IAN), LOCATED APPROXIMATELY 302 NM EAST-
NORTHEAST OF SUVA, FIJI, HAS TRACKED EAST-SOUTHEASTWARD AT 02 KNOTS
OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE IMAGERY
SHOWS THAT OVER THE PAST 12 HOURS THE SYSTEM HAS UNDERGONE A PERIOD
OF RAPID INTENSIFICATION. ALTHOUGH TC 07P REMAINS A COMPACT SYSTEM,
THE LOW LEVEL CIRCULATION CENTER (LLCC) AND SUPPORTING UPPER LEVEL
ENVIRONMENT HAS ALLOWED FOR THE DEVELOPMENT OF A WELL-DEFINED EYE
FEATURE. A RECENT 090552Z SSMIS MICROWAVE PASS INDICATES A PINHOLE
EYE REMAINS AND HAS BEEN USED IN THE PLACEMENT OF THE SYSTEM. OVER
THE PAST FEW HOURS THE TRACK HAS STARTED TO MOVE EASTWARD AND
APPEARS TO BE BECOMING MORE ENGAGED BY THE NEAR EQUATORIAL RIDGE
(NER) AS A MID-LATITUDE TROUGH CONTINUES TO TRACK OVER NEW ZEALAND,
WEAKENING THE SUB-TROPICAL RIDGE (STR) TO THE SOUTH OF TC 07P. MODEL
GUIDANCE INDICATES THE TROUGH WILL CONTINUE TO SHIFT THE STR,
EVENTUALLY MERGING WITH THE NER CAUSING AN INCREASE IN TRACK SPEED
FOR TC 07P AROUND TAU 36 TO 48. IN THE LATER TAUS, INTERACTION WITH
THE MID-LATITUDE WESTERLIES WILL LEAD TO A WEAKENING TREND BY TAU
72. TC 07P IS FORECAST TO BEGIN EXTRA-TROPICAL TRANSITION BY TAU 96.
AS THE CURRENT POSITIONING ALIGNS WITH THE PREVIOUS FORECAST, THERE
HAS BEEN A SLIGHT INCREASE IN THE CONFIDENCE FOR THE FORECAST TRACK,
BUT OVERALL CONFIDENCE REMAINS LOW DUE TO THE RECENT NATURE OF THE
TRACK CHANGES. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 090600Z IS 20
FEET. NEXT WARNINGS AT 092100Z AND 100900Z.//
NNNN

[hurricanes1234]

What did the 12z JTWC Best Track say? I'm seeing 90 knots on 18z, so it looks to have either intensified or maintained its intensity.

07P IAN 140109 1800 17.1S 175.8W SHEM 90 956

[stormkite]

SH072014 IAN for Run: 2014-01-09 18Z (Noaa)


http://www.ssd.noaa.gov/PS/TROP/mtcswa. ... 014&id=IAN


RMS
FKPS01 NFFN 091849 2014009 1849
TC ADVISORY
DTG: 20140109/1800Z
TCAC: NFFN
TC: IAN
NR: 17
PSN: S1706 W17548
MOV: ESE 04KT
C: 955HPA
MAX WIND: 90KT
FCST PSN +6HR: 10/0000 S1724 W17524
FCST MAX WIND +6HR: 90KT
FCST PSN +12HR: 10/0600 S1742 W17454
FCST MAX WIND +12HR: 85KT
FCST PSN +18HR: 10/1200 S1812 W17436
FCST MAX WIND +18HR: 85KT
FCST PSN +24HR: 10/1800 S1842 W17412
FCST MAX WIND +24HR: 80KT
RMK: NIL
NXT MSG: 20140110/0100Z
wxtlist.k: done




TROPICAL CYCLONE IAN ANALYSED POSITION : 16.8S 176.0W^M

VERIFYING TIME POSITION STRENGTH TENDENCY
-------------- -------- -------- -------
12UTC 09.01.2014 16.8S 176.0W STRONG
00UTC 10.01.2014 17.5S 175.0W MODERATE LITTLE CHANGE
12UTC 10.01.2014 18.2S 174.3W MODERATE WEAKENING SLIGHTLY
00UTC 11.01.2014 19.8S 173.9W MODERATE LITTLE CHANG
12UTC 11.01.2014 21.4S 173.8W MODERATE INTENSIFYING SLIGHTLY
00UTC 12.01.2014 23.0S 173.5W MODERATE LITTLE CHANGE
12UTC 12.01.2014 25.1S 173.0W STRONG INTENSIFYING SLIGHTLY
00UTC 13.01.2014 27.2S 172.2W STRONG LITTLE CHANGE
12UTC 13.01.2014 28.3S 171.8W MODERATE WEAKENING RAPIDLY
/tmp/fileNuxfbJ


Personal Forecast Disclaimer:
The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products

[stormkite]

cinnamon roll cyclone


TROPICAL CYCLONE ADVISORY NUMBER TWENTY NINE (29) FOR TONGA ON SEVERE TROPICAL
CYCLONE IAN ISSUED FROM THE FUA'AMOTU TROPICAL CYCLONE WARNING CENTRE AT 1:00PM
FRIDAY JANUARY 10TH 2014.

A TROPICAL CYCLONE WARNING

A HURRICANE WARNING REMAINS INFORCE FOR THE VAVAU GROUP.

A STORM WARNING REMAINS IN FORCE AND A HURRICANE ALERT IS NOW IN FORCE FOR THE
HA'APAI GROUP.

THE GALE WARNING PREVIOUSLY IN FORCE FOR NIUAFO'OU IS NOW CANCELLED.

A TROPICAL CYCLONE ALERT REMAINS IN FORCE FOR TONGATAPU AND 'EUA.

A STRONG WIND WARNING REMAINS INFORCE FOR NIUAFO'OU, NIUATOPUTAPU, TAFAHI
TONGATAPU, 'EUA AND SURROUNDING ISLANDS.

A HEAVY DAMAGING SWELL ADVISORY REMAINS INFORCE FOR COASTAL WATERS OF
VAVA'U AND HA'APAI GROUP.

A HEAVY RAIN ADVISORY IS NOW IN FORCE FOR THE VAVA'U AND HA'APAI GROUPS.

SEVERE TROPICAL CYCLONE IAN CATEGORY 4 WAS LOCATED NEAR 17 DECIMAL 2 SOUTH 175
DECIMAL 5 WEST OR ABOUT 180KM SOUTH OF NIUAFO'OU OR ABOUT 230KM NORTHWEST
OF VAVA'U AT 10:00AM THIS MORNING.TROPICAL CYCLONE IAN HAS ESTIMATED WINDS OF
90KNOTS NEAR ITS CENTRE WITH MOMENTARY GUSTS UP TO 125KNOTS.THE CYCLONE IS
NOW MOVING SOUTHEAST AT 6KNOTS.

ON ITS CURRENT TRACK, TROPICAL CYCLONE IAN MAY BRING:

DAMAGING GALE FORCE WINDS TO VAVA'U IN THE 3-6HRS, DESTRUCTIVE STORM FORCE
WINDS IN THE NEXT 6-12HRS AND VERY DESTRUCTIVE HURRICANE FORCE WINDS IN THE
NEXT 12-18HRS

FOR THE HA'APAI GROUP TROPICAL CYCLONE IAN MAY BRING DAMAGING GALE FORCE
WINDS IN THE NEXT 6-12HRS, DESTRUCTIVE STORM FORCE WINDS IN THE NEXT 12-18
AND POSSIBLE VERY DESTRUCTIVE HURRICANCE FORCE WINDS IN THE NEXT 24 TO 36HR.

FOR TONGATAPU AND EUA THE CYCLONE MAY BRING DAMAGING GALE FORECE WINDS IN THE
NEXT 24-48HRS

WEATHER FORECAST FOR TONGA:

FOR THE VAVA'U GROUP:
NORTH TO NORTHEAST WINDS 15-20KT INCREASING TO 45-55KTS WITH MOMENTARY GUST
UP TO 65 T0 75KT IN THE NEXT 6-12HRS AND FURTHER INCREASING TO 65 KNOTS WITH
GUST UP TO 85 IN THE NEXT 12-18HRS. OVERCAST WITH RAIN DEVELOPING WITH FLASH
FLOODING EXPECTED.HIGH SEAS WITH DAMAGING HEAVY NORTHWEST SWELLS DEVELOPING.
SEA FLOODING OF NORTHERN COASTS LIKELY.

FOR THE HA'APAI GROUPS:
EAST WINDS 15-20 INCREASING TO 45-50KT WITH MOMENTARY GUST TO 55-60KT IN THE
NEXT 12-18HR. BECOMING OVERCAST WITH RAIN DEVELOPING.FLASH FLOODING EXPECTED.
SEAS BECOMING ROUGH TO VERY ROUGH WITH DAMAGING HEAVY NORTHWEST SWELLS
DEVELOPING.SEA FLODDING OF LOW LYING COASTAL AREAS POSIBLE.

FOR NIUAFO'OU:
WEST WINDS 20-25KTS WITH MOMENTARY GUSTS UP 30-35KT BUT EASING TODAY. RAIN
EASING.SEAS ROUGH TO VERY ROUGH WITH HEAVY SOUTHWEST SWELL.

FOR NIUATOPUTAPU AND TAFAHI:
NORTHWEST WINDS INCREASING TO 20-30KTS AT TIMES. CLOUDY PERIODS WITH
OCCASIONAL SHOWERS. SEAS BECOMING ROUGH WITH MODERATE NORTHWEST SWELLS.

FOR TONGATAPU AND 'EUA:
SOUTHEAST WINDS 15-20KTS POSSIBLY INCREASING TO 30-35 KNOTS IN THE NEXT 24-48
HOURS. EXPECT RAIN, HEAVY AT TIMES IN THE NEXT 24-48HOURS. ROUGH SEAS WITH
HEAVY SWELLS DEVELOPING.

TEMPERATURE FORECAST FOR NUKU'ALOFA:
MAX: 31 DEGREES CELSIUS TODAY.
MIN: 25 DEGREES CELSIUS TONIGHT.

TIDE PREDICTIONS:
HIGH TIDE : 03:10PM
LOW TIDE : 09:35PM

THE MEAN SEA LEVEL PRESSURE RECORDED AT FUA'AMOTU AT 1:00PM WAS 1004.3MB

THE NEXT TROPICAL CYCLCONE ADVISORY ON SEVERE TROPICAL CYCLONE IAN WILL BE
ISSUED AROUND 4:00PM TODAY.

[hurricanes1234]

Is there something stopping Ian from intensifying? Very odd system.

[mrbagyo]

^what?? it's still intensifying but just gradual

[euro6208]

07P IAN 140110 1200 18.4S 174.9W SHEM 105 944

Category 3 cyclone!!!

[Meow]

RSMC Nadi’s Category 5 Severe Tropical Cyclone

TROPICAL DISTURBANCE ADVISORY NUMBER A21 ISSUED FROM RSMC NADI
Jan 10/1348 UTC 2014 UTC.

SEVERE TROPICAL CYCLONE IAN 07F CENTRE 930HPA CAT 5 WAS LOCATED NEAR
18.2S 174.9W AT 101200 UTC. POSITION GOOD BASED ON HR MTSAT EIR
IMAGERY AND PERIPHERAL SURFACE REPORTS. CYCLONE MOVING
SOUTH-SOUTHEAST AT ABOUT 04 KNOTS. MAXIMUM 10-MINUTE AVERAGE WINDS
NEAR THE CENTRE ESTIMATED AT ABOUT 110 KNOTS.

EXPECT WINDS ABOVE 63 KNOTS WITHIN 20 NAUTICAL MILES OF CENTRE,
ABOVE 47 KNOTS WITHIN 40 NAUTICAL MILES OF CENTRE AND
ABOVE 33 KNOTS WITHIN 80 NAUTICAL MILES OF CENTRE.

DEEP CONVECTION REMAINS PERSISTANT PAST 12 HOURS. EYE DISCERNIBLE AND
WARMING. CLOUD TOPS COOLING RAPIDLY PAST 6 HOURS. IAN LIES IN A LOW
SHEARED ENVIRONMENT JUST SOUTH OF AN UPPER RIDGE. OUTFLOW FAIR TO
SOUTH AND EAST BUT RESTRICTED ELSEWHERE. SST AROUND 28 DEGREES
CELCIUS. SYSTEM IS MOVING SOUTHEASTWARDS ON THE SOUTHERN PERIPHERY OF
THE NEAR EQUATORIAL RIDGE TO THE NORTHWEST OF THE SYSTEM. DVORAK
ANALYSIS BASED ON EYE PATTERN WITH OW EYE SURROUNDED BY W EMBEDDED IN
CMG YIELDS DT OF 6.5, MET=6.0 AND PT=6.5. FT BASED ON DT THUS,
T6.5/6.5/D2.0/24HRS.

GLOBAL MODELS AGREE ON A SOUTHEASTWARD MOVEMENT WITH GRADUAL
WEAKENING AFTER 24 HOURS.

FORECASTS :
AT 12 HRS VALID AT 110000 UTC 19.4S 174.4W MOV SSE AT 06 KT WITH 100
KT CLOSE TO CENTRE
AT 24 HRS VALID AT 111200 UTC 20.8S 173.9W MOV SSE AT 07 KT WITH 85
KT CLOSE TO CENTRE

OUTLOOK :
AT 36 HRS VALID AT 120000 UTC 22.4S 173.4W MOV SSE AT 07 KT WITH 70
KT CLOSE TO CENTRE
AT 48 HRS VALID AT 121200 UTC 24.1S 172.9W MOV SSE AT 08 KT WITH 50
KT CLOSE TO CENTRE


THE NEXT TROPICAL DISTURBANCE ADVISORY ON SEVERE TROPICAL CYCLONE IAN
WILL BE ISSUED AROUND 102000 UTC.

[euro6208]

07P IAN 140110 1800 18.9S 174.8W SHEM 120 933

holy bonanza! category 4 cyclone (SSHS) on the JTWC best track!