Thought it might pay to start a thread on this TD which had been producing severe thundertorms over Fiji over the last few days. It's actually a merger of 2 TD's, which RSMC Nadi have been monitoring since early last week and looks likely to become the SW Pacific's 5th named TC by tomorrow, albeit a not very significant one…
TROPICAL DISTURBANCE ADVISORY NUMBER A3 ISSUED FROM RSMC NADI
Feb 27/2003 UTC 2014 UTC.
TROPICAL DEPRESSION 15F CENTRE 997HPA WAS LOCATED NEAR 15.1S 180.0E
AT 271800 UTC. POSITION FAIR BASED ON HR GMS EIR/VIS IMAGERY AND
PERIPHERAL SURFACE REPORTS. TD15F MOVING NORTHEAST AT ABOUT 07
KNOTS. MAXIMUM 10-MINUTE AVERAGE WINDS NEAR THE CENTRE ESTIMATED AT
ABOUT 25 KNOTS.
DEEP CONVECTION REMAINS PERSISTANT PAST 24 HOURS. ORGANISATION HAS
SLIGHTLY IMPROVED PAST 24 HOURS. SYSTEM LIES NORTH OF AN UPPER RIDGE
IN A MODERATE SHEARED ENVIRONMENT. OUTFLOW FAIR TO THE SOUTH BUT
RESTRICTED ELSEWHERE. SST AROUND 30 DEGREES CELCIUS. CYCLONIC
CIRCULATION EXTENDS UPTO 500HPA. DVORAK ANALYSIS BASED ON 0.35 WRAP
ON LOG10 SPIRAL YEILDING DT OF 2.0, MET=2.5 AND PT=2.0. FT BASED ON
DT THUS, T2.0/2.0/S0.0/24HRS.
GLOBAL MODELS AGREE ON A EASTWARD MOVEMENT BEFORE CURVING IT
SOUTHEASTWARDS WITH FURTHER INTENSIFICATION.
POTENTIAL FOR TD15F TO DEVELOP INTO A TROPICAL CYCLONE IN THE NEXT 24
TO 48 HOURS IS MODERATE TO HIGH.
WTPS21 PGTW 272100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE FORMATION ALERT//
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
125 NM EITHER SIDE OF A LINE FROM 15.1S 177.7E TO 19.0S 178.3W
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 25 TO 30 KNOTS. METSAT
IMAGERY AT 271800Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 16.1S 178.7E. THE SYSTEM IS MOVING NORTHEASTWARD AT 04
KNOTS.
2. REMARKS: THE AREA OF CONVECTION PREVIOUSLY LOCATED NEAR 18.1S
178.6E, IS NOW LOCATED NEAR 16.1S 178.7E, APPROXIMATELY 120 NM EAST
OF NADI, FIJI. ANIMATED INFRARED SATELLITE IMAGERY SHOWS FLARING
FORMATIVE CONVECTIVE BANDING WRAPPING AROUND A POORLY DEFINED LOW
LEVEL CIRCULATION CENTER. A 271718Z SSMIS MICROWAVE IMAGE SHOWS A
DEFINED SYSTEM DESPITE THE CONVECTIVE ORGANIZATION OF THE SYSTEM
REMAINING FAIRLY BROKEN. THE RADAR LOOP FROM LABASA, FIJI, IS
SHOWING THE LOW LEVEL STRUCTURE OF THE SYSTEM IS ILL DEFINED AS THE
ISLANDS SEEM TO BE DISRUPTING THE LOW-LEVEL INFLOW. UPPER-LEVEL
ANALYSIS INDICATES THE SYSTEM IS LOCATED NEAR THE RIDGE AXIS IN AN
AREA OF LOW (05 TO 10 KNOTS) VERTICAL WIND SHEAR AND FAVORABLE
POLEWARD AND EQUATORWARD OUTFLOW. SEA SURFACE TEMPERATURES ARE
CONDUCIVE FOR DEVELOPMENT (30 DEGREES CELSIUS). NUMERICAL MODELS
INDICATE SIGNIFICANT DEVELOPMENT OVER THE NEXT 48 HOURS AS THE
SYSTEM MOVES POLEWARD FROM THE ISLANDS OF FIJI. MAXIMUM SUSTAINED
SURFACE WINDS ARE ESTIMATED AT 20 TO 25 KNOTS. MINIMUM SEA LEVEL
PRESSURE IS ESTIMATED TO BE NEAR 999 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
282100Z.
//
NNNN
You do not have the required permissions to view the files attached to this post.
JTWC already seemed to have deemed this system a TC earlier this evening…
WTPS31 PHNC 280900
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 16P (SIXTEEN) WARNING NR 001//
RMKS/
1. TROPICAL CYCLONE 16P (SIXTEEN) WARNING NR 001
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
WIND RADII VALID OVER OPEN WATER ONLY
---
WARNING POSITION:
280600Z --- NEAR 16.1S 179.5W
MOVEMENT PAST SIX HOURS - 110 DEGREES AT 09 KTS
POSITION ACCURATE TO WITHIN 020 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
WIND RADII VALID OVER OPEN WATER ONLY
…
REMARKS:
280900Z POSITION NEAR 16.5S 179.2W.
TROPICAL CYCLONE (TC) 16P (SIXTEEN), LOCATED APPROXIMATELY 170 NM
NORTHEAST OF SUVA, FIJI, HAS TRACKED EAST-SOUTHEASTWARD AT 09
KNOTS OVER THE PAST SIX HOURS. ANIMATED MULTISPECTRAL SATELLITE
IMAGERY (MSI) SHOWS THE SYSTEM HAS FURTHER CONSOLIDATED AS FORMATIVE
BANDS WRAPPED TIGHTER INTO A LOW LEVEL CIRCULATION CENTER THAT HAS
BECOME BETTER-DEFINED. THE INITIAL POSITION IS BASED ON THE MSI LOOP
WITH FAIR CONFIDENCE. THE INITIAL INTENSITY IS BASED ON THE HIGHER
END OF DVORAK ESTIMATES FROM PGTW, KNES, NFFN, AND ABRF. UPPER LEVEL
ANALYSIS INDICATES THE SYSTEM IS UNDER A RIDGE AXIS IN AN AREA OF
LIGHT TO MODERATE (10-15 KNOT) VERTICAL WIND SHEAR (VWS) AND GOOD
POLEWARD OUTFLOW. A MID-LAYERED SUBTROPICAL RIDGE TO THE EAST HAS
ASSUMED STEERING AND IS EXPECTED TO BE THE DOMINANT DRIVER OF THE
CYCLONE THROUGHOUT THE FORECAST. TC 16P WILL GRADUALLY INTENSIFY,
PEAKING AT 60 KNOTS FROM TAU 72-96 BEFORE ACCELERATING TOWARDS
EXTRA-TROPICAL TRANSITION AND HIGHER VWS. THE AVAILABLE NUMERIC
GUIDANCE IS IN TIGHT AGREEMENT, LENDING HIGH CONFIDENCE TO THE JTWC
TRACK FORECAST. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 280600Z IS 10
FEET. NEXT
WARNINGS AT 282100Z AND 010900Z. THIS WARNING SUPERSEDES AND
CANCELS REF A (WTPS21 PGTW 272100). //
NNNN
TROPICAL DISTURBANCE ADVISORY NUMBER A5 ISSUED FROM RSMC NADI
Feb 28/0811 UTC 2014 UTC.
TROPICAL DEPRESSION 15F CENTRE 995HPA WAS LOCATED NEAR 16.0S 179.6W
AT 280600 UTC. POSITION GOOD BASED ON RADAR IMAGERY AND PERIPHERAL
SURFACE REPORTS. TD15F MOVING SOUTHEAST AT ABOUT 08 KNOTS. MAXIMUM
10-MINUTE AVERAGE WINDS NEAR THE CENTRE ESTIMATED AT ABOUT 30 KNOTS.
DEEP CONVECTION REMAINS PERSISTANT PAST 12 HOURS. ORGANISATION HAS
SLIGHTLY IMPROVED PAST 24 HOURS. SYSTEM LIES JUST SOUTH OF AN UPPER
RIDGE IN A HIGH SHEARED ENVIRONMENT. OUTFLOW GOOD TO THE NORTH BUT
RESTRICTED ELSEWHERE. SST AROUND 30 DEGREES CELCIUS. CYCLONIC
CIRCULATION EXTENDS UPTO 500HPA. DVORAK ANALYSIS BASED ON 0.40 WRAP
ON LOG10 SPIRAL YEILDING DT OF 2.5, MET AND PT AGREE. FT BASED ON DT
THUS, T2.5/2.5/D0.5/24HRS.
GLOBAL MODELS AGREE ON A SOUTHEASTWARD MOVEMENT WITH FURTHER
INTENSIFICATION.
POTENTIAL FOR TD15F TO DEVELOP INTO A TROPICAL CYCLONE IN THE NEXT 24
TO 48 HOURS IS HIGH.
You do not have the required permissions to view the files attached to this post.
Still officially a TD this morn according to RSMC Nadi, but I expect that'll change later today. Not sure why JTWC insist on applying their 1-minute wind speeds to our BoM/Fiji TC scale though, i.e. 35 kt 1-minute winds only equal about 31 kt 10-minute winds.
Also been some serious flooding in Fiji from this TD recently. Some rainfall totals include 334mm in the 48 hrs to 9am of Friday at Laucala Bay in Suva, and 311mm in just 24 hrs to 9am on Thursday in the island of Matuku. Tonga's turn next.
TROPICAL DISTURBANCE ADVISORY NUMBER A7 ISSUED FROM RSMC NADI
Feb 28/1956 UTC 2014 UTC.
TROPICAL DEPRESSION 15F CENTRE 995HPA WAS LOCATED NEAR 17.8S 178.8W
AT 281800 UTC. POSITION FAIR BASED ON HR MTSAT EIR IMAGERY AND
PERIPHERAL SURFACE REPORTS. DEPRESION MOVING SOUTH-SOUTHEAST AT
ABOUT 08 KNOTS. MAXIMUM 10-MINUTE AVERAGE WINDS NEAR THE CENTRE
ESTIMATED AT ABOUT 30 KNOTS.
CONVECTION REMAINS PERSISTANT PAST 24 HOURS. OVERALL ORGANISATION HAS
IMPROVED PAST 24 HOURS. PRIMARY BANDS TRYING TO WRAP AROUND LLCC.
SYSTEM LIES UNDER AN UPPER RIDGE IN A LOW SHEARED ENVIRONMENT.
OUTFLOW GOOD TO THE SOUTH AND NORTH. SST AROUND 30 DEGREES CELCIUS.
CYCLONIC EXTENDS UPTO 500HPA. SYSTEM IS BEING STEERED TO THE
SOUTHEAST BY A MID LEVEL SUBTROPICAL RIDGE TO THE EAST. DVORAK
ANALYSIS BASED ON 0.5 WRAP ON LOG10 SPIRAL YEILDING DT OF 2.5,
MET=2.5 AND PT=2.5. FT BASED ON DT THUS, T2.5/2.5/D0.5/24HRS.
GLOBAL MODELS AGREE ON A SOUTH-SOUTHEAST MOVEMENT WITH FURTHER
INTENSIFICATION.
POTENTIAL FOR TD15F TO DEVELOP INTO A TROPICAL CYCLONE IN THE NEXT 12
TO 18 HOURS IS HIGH.
...
WTPS31 PHNC 282100
MSGID/GENADMIN/JOINT TYPHOON WRNCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE 16P (SIXTEEN) WARNING NR 002//
RMKS/
1. TROPICAL CYCLONE 16P (SIXTEEN) WARNING NR 002
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
…
REMARKS:
282100Z POSITION NEAR 18.0S 178.7W.
TROPICAL CYCLONE (TC) 16P (SIXTEEN), LOCATED APPROXIMATELY 157 NM
EAST OF SUVA, FIJI, HAS TRACKED SOUTH-SOUTHEASTWARD AT 09 KNOTS
OVER THE PAST SIX HOURS. ANIMATED ENHANCED INFRARED SATELLITE
IMAGERY DEPICTS CURVED CONVECTIVE BANDING WRAPPING BROADLY INTO THE
LOW-LEVEL CIRCULATION CENTER (LLCC). A 281802Z SSMIS IMAGE SHOWS A
DEFINED BUT ELONGATED LLCC. RECENT SCATTEROMETRY DATA ALSO REVEALS A
BROAD CIRCULATION WITH 25 TO 30 KNOT WINDS WHILE SURFACE
OBSERVATIONS SHOW SLP NEAR 997MB, WHICH CORRESPONDS TO 30 T0 35 KNOT
MAXIMUM SUSTAINED SURFACE WINDS. THE CURRENT INTENSITY REMAINS
ASSESSED AT 35 KNOTS BASED ON DVORAK ESTIMATES OF 35 KNOTS FROM ALL
AGENCIES. THE CURRENT POSITION IS BASED ON THE AFOREMENTIONED SSMIS
IMAGE WITH FAIR CONFIDENCE. TC 16P IS TRACKING ALONG THE WESTERN
PERIPHERY OF THE SUBTROPICAL RIDGE (STR) AND IS FORECAST TO
GRADUALLY ACCELERATE AFTER TAU 36 AS IT BEGINS TO TRACK INTO AN AREA
OF ENHANCED POLEWARD FLOW SITUATED BETWEEN THE STR AND AN
APPROACHING DEEP MIDLATITUDE TROUGH. BY TAU 48, TC 16P SHOULD BEGIN
EXTRA-TROPICAL TRANSITION (ETT) AS IT INTERACTS WITH THE TROUGH AND
BAROCLINIC ZONE. AFTER TAU 72, THE SYSTEM WILL ENCOUNTER INCREASING
VERTICAL WIND SHEAR AND COOLER SST, WHICH WILL SERVE TO WEAKEN THE
SYSTEM RAPIDLY. TC 16P IS FORECAST TO COMPLETE ETT BY TAU 96 AS IT
BECOMES FULLY-EMBEDDED IN THE BAROCLINIC ZONE AND GAINS FRONTAL
CHARACTERISTICS. THERE IS HIGH CONFIDENCE IN THE FORECAST DUE TO THE
TIGHT GROUPING OF DYNAMIC GUIDANCE. MAXIMUM SIGNIFICANT WAVE HEIGHT
AT 281800Z IS 11 FEET. NEXT WARNINGS AT 010900Z AND 012100Z.//
NNNN
You do not have the required permissions to view the files attached to this post.
STORM WARNING 001 ISSUED FROM RSMC NADI Mar 01/0107 UTC 2014 UTC.
TROPICAL CYCLONE KOFI CENTRE 990HPA CATEGORY 1 WAS LOCATED NEAR 19.4
SOUTH 177.5 WEST AT 010000 UTC.
POSITION FAIR.
REPEAT POSITION 19.4S 177.5W at 010000 UTC.
CYCLONE MOVING SOUTHEAST AT 14 KNOTS. CYCLONE INTENSIFYING.
EXPECT SUSTAINED WINDS OF 35 KNOTS CLOSE TO THE CENTRE INCREASING TO
50 KNOTS BY 020000 UTC.
...
You do not have the required permissions to view the files attached to this post.
TROPICAL DISTURBANCE ADVISORY NUMBER A8 ISSUED FROM RSMC NADI
Mar 01/0155 UTC 2014 UTC.
TROPICAL CYCLONE KOFI CENTRE 990HPA CAT 1 WAS LOCATED NEAR 19.4S
177.5W AT 010000 UTC. POSITION FAIR BASED ON HR MTSAT EIR AND VIS
IMAGERY AND PERIPHERAL SURFACE REPORTS. CYCLONE MOVING SOUTHEAST AT
ABOUT 14 KNOTS. MAXIMUM 10-MINUTE AVERAGE WINDS NEAR THE CENTRE
ESTIMATED AT ABOUT 35 KNOTS.
…
OVERALL ORGANISATION HAS SIGNIFICANTLY IMPROVED PAST 24 HOURS. DEEP
CONVECTION REMAINS PERSISTANT PAST 12 HOURS. PRIMARY BANDS TIGHTLY
WRAPPING AROUND LLCC. SYSTEM LIES UNDER AN UPPER RIDGE IN A LOW
SHEARED ENVIRONMENT. OUTFLOW GOOD TO THE NORTH AND SOUTH. SST AROUND
30 DEGREES CELCIUS. SYSTEM IS BEING STEERED TO THE SOUTHEAST BY MID
LEVEL SUBTROPICAL RIDGE TO THE EAST. DVORAK ANALYSIS BASED ON 0.6
WRAP ON LOG10 SPIRAL YEILDING DT OF 3.0, MET=3.0 AND PT=3.0. FT BASED
ON DT THUS, T3.0/3.0/D1.0/24HRS.
GLOBAL MODELS AGREE ON A SOUTHEAST MOVEMENT WITH GRADUAL
INTENSIFICATION.
...
You do not have the required permissions to view the files attached to this post.
