Tropical Cyclone Zita 07F (Weakening)

[Chacor]

Tropical Disturbance Summary For area Equator to 25S, 160E to 120W
issued from RSMC NADI Jan 21/1332 UTC 2007 UTC.

TROPICAL DEPRESSION 07F [1001 HPA] CENTRE WAS LOCATED NEAR 12.2S
164.6W AT 210730 UTC MOVING SOUTHEAST 105 KNOTS. POSITION POOR BASED
ON MTSAT EIR IMAGERY WITH ANIMATION, PERIPHERAL SURFACE OBSERVATIONS
AND QSCAT DATA. SYSTEM OVERALL ORGAINISATION HAS IMPROVED RAPIDLY
SINCE PAST 12 HOURS. 07F REMAINS IN FAVOURABLE AREA WITH UPPER
DIVERGENCE PERSISTING AT 250HPA. SHEAR IS MINIMAL. OUTLOW GOOD IN ALL
QUARDRANTS. BAND WRAPS 0.4 ON LOG10 SPIRAL YIELDING DT=2.5 PATTERN
AGREES.
FINAL T NUMBER CONTRAINTED BY RULES THUS YIELDING
T2.0/2.0/D1.0/12HRS. GLOBAL MODELS INDICATE SLOW DEVELOPMENT IN THE
NEXT 24 HOURS AND EITHER KEEP THE SYSTEM IN THE AREA OR HAVE GRADUAL
SOUTHEAST MOVEMENT.

THE POTENTIAL FOR 07F TO DEVELOP INTO A TROPICAL CYCLONE IN THE NEXT
24 TO 48 HOURS IS LOW TO MODERATE.

From JTWC:
F. T1.5/1.5/INIT OBS (21/1130Z)

[P.K.]

Low potential for an upgrade to a TC within the next 24 to 48 hours.

Tropical Disturbance Summary For area Equator to 25S, 160E to 120W
issued from RSMC NADI Jan 21/2352 UTC 2007 UTC.

CORRECTION TO TD 08F MOVEMENT...

TROPICAL DEPRESSION 07F [1001 HPA] CENTRE WAS LOCATED NEAR 12.0S
162.1W AT 212100 UTC MOVING EASTERLY 10 KNOTS. POSITION POOR BASED ON
GOES EIR/VIS IMAGERY WITH ANIMATION. 07F IS MOVING INTO INCREASING
SHEAR. OVERALL ORGANISATION DECREASED MARKEDLY PAST 6 TO 12 HOURS.
OUTLOW GOOD TO NORTH BUT RESTRICTED ELSEWHERE.
THE POTENTIAL FOR 07F TO DEVELOP INTO A TROPICAL CYCLONE IN THE NEXT
24 TO 48 HOURS IS LOW.

TROPICAL DEPRESSION 08F [1000 HPA] CENTRE WAS LOCATED NEAR 12.3S
176.1W AT 212100 UTC MOVING EAST-SOUTHEAST ABOUT 05 KNOTS. POSITION
POOR BASED ON MTSAT VIS/EIR IMAGERY WITH ANIMATION AND SCATTEROMETER
DATA. ORGAINISATION IMPROVED PAST 6 TO 12 HOURS THOUGH DIURNAL
INFLUENCE EVIDENT. 08F LOCATED IN A FAVOURABLE ENVIRONMENT WITH
MINIMAL SHEAR. OUTLOW DEVELOPING TO SOUTH AND NORTH. DVORAK BASED ON
WRAP OF 0.35 ON LOG10 SPIRAL YIELDING DT2.0. PT AND MET AGREE. THUS
T2.0/2.0/D1.0/24HRS.
GLOBAL MODELS INDICATE DEVELOPMENT IN THE NEXT 24 HOURS WITH GRADUAL
EASTWARD MOVEMENT.

THE POTENTIAL FOR 08F TO DEVELOP INTO A TROPICAL CYCLONE IN THE NEXT
24 TO 48 HOURS IS MODERATE TO HIGH.

NO OTHER SIGNIFICANT DISTURBANCES ANALYSED OR FORECAST IN THE AREA.

Edit - Also a T3.0 from TCWC Brisbane but the position of the centre given is rather different.

Tropical Low East of Samoa

222300 UTC

14.7S 156.7W

Analysis based on: GOES EIR and VIS 222200 UTC and SSMI 221878 UTC pass.

Latitude Detection Sum : 12

Longitude Detection Sum: 19

Dvorak analysis: Has formed CDO with partial eye evident on SSMI image. Too
early for embd centre so based on Pattern type and MET.

T3.0/3.0/D1.5/24HRS

[P.K.]

Now TC Zita. 995hPa, 35kt winds.

[P.K.]

Continuing to deepen, 990hPa now with 40kt winds.

TC ADVISORY
DTG:200701230100Z
TCAC:NFFN
TC:ZITA
NR:01
PSN:S1500 W15606
MOV:SE 14KT
C:990HPA
MAX WIND:40KT
FCST PSN + 12 HR:S1724 W15400
FCST MAX WIND + 12 HR:45KT
FCST PSN + 18 HR:S1848 W15306
FCST MAX WIND + 18 HR:50KT
FCST PSN + 24 HR:S2018 W15218
FCST MAX WIND + 24 HR:55KT
NXT MSG:20070123/1330Z

[HurricaneBill]

Wow, I didn't realize Zita was in the area of Tahiti!

Classic example of the presence of El Nino. (Although La Ninas have also produced cyclones in that area on occasions.)

[Chacor]

JTWC have this becoming extratropical, oddly enough.

SUBJ: TROPICAL CYCLONE 08P (ZITA) WARNING NR 002
WTPS31 PGTW 230900
1. TROPICAL CYCLONE 08P (ZITA) WARNING NR 002
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
---
WARNING POSITION:
230600Z --- NEAR 16.0S 154.5W
MOVEMENT PAST SIX HOURS - 125 DEGREES AT 19 KTS
POSITION ACCURATE TO WITHIN 040 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 060 KT, GUSTS 075 KT
RADIUS OF 050 KT WINDS - 035 NM NORTHEAST QUADRANT
035 NM SOUTHEAST QUADRANT
035 NM SOUTHWEST QUADRANT
035 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 105 NM NORTHEAST QUADRANT
105 NM SOUTHEAST QUADRANT
095 NM SOUTHWEST QUADRANT
095 NM NORTHWEST QUADRANT
REPEAT POSIT: 16.0S 154.5W
---
FORECASTS:
12 HRS, VALID AT:
231800Z --- 19.3S 151.7W
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
BECOMING EXTRATROPICAL
RADIUS OF 034 KT WINDS - 095 NM NORTHEAST QUADRANT
095 NM SOUTHEAST QUADRANT
085 NM SOUTHWEST QUADRANT
085 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 165 DEG/ 26 KTS
---
24 HRS, VALID AT:
240600Z --- 24.3S 150.2W
MAX SUSTAINED WINDS - 040 KT, GUSTS 050 KT
EXTRATROPICAL
---
REMARKS:
230900Z POSITION NEAR 16.8S 153.8W.
TROPICAL CYCLONE (TC) 08P (ZITA), LOCATED APPROXIMATELY 330 NM
WEST-NORTHWEST OF TAHITI, HAS TRACKED SOUTHEASTWARD AT 19 KNOTS
OVER THE PAST SIX HOURS. RECENT ANIMATED INFRARED AND WATER VAPOR
SATELLITE IMAGERY SHOW THE SYSTEM TRACKING SOUTHEASTWARD UNDER
THE STEERING INFLUENCE OF LOW TO MID LEVEL SUBTROPICAL RIDGING
NORTHEAST OF THE SYSTEM AND BEGINNING TO ACCELERATE SOUTHEASTWARD
AHEAD OF AN APPROACHING MIDLATITUDE TROUGH. GOOD POLEWARD UPPER
LEVEL OUTFLOW AND LOW TO MODERATE VERTICAL WIND SHEAR HAVE ALLOWED
THE SYSTEM TO FURTHER INTENSIFY OVER THE PAST 12 HOURS. HOWEVER,
THE STORM IS EXPECTED TO WEAKEN SLOWLY DURING THE UPCOMING 12
HOURS AS INCREASED NORTHWESTERLY VERTICAL WIND SHEAR AND ENTRAIN-
MENT OF DRIER AIR ASSOCIATED WITH THE APPROACHING TROUGH BEGIN TO
HAVE AN EFFECT. THE STORM WILL CONTINUE TO INTERACT WITH THIS
TROUGH DURING THE FORECAST PERIOD, BECOMING FULLY EXTRATROPICAL
BY TAU 24. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 230600Z IS 14 FEET.
NEXT WARNING AT 232100Z.//
BT

[Chacor]

Tropical Disturbance Advisory Number B2 issued from RSMC NADI
Jan 23/0748 UTC 2007 UTC.

Tropical Cyclone ZITA 07F [985hPa] centre was located near 16.1S
154.5W at 230600 UTC. Position poor based on HRES GOES EIR imagery
with animation. Cyclone moving southeast at 15 knots and expected to
accelerate further. Maximum 10-minute average winds estimated at 50
knots close to the centre increasing to 60 knots in the next 12 to 24
hours. Expect winds over 47 knots within 30 miles of centre and winds
over 33 knots within 90 miles of centre in the northern semicircle
and within 120 miles of centre in the southern semicircle.

Organisaton significantly increased past 6 hours with CDO developing
over LLCC and cold bands wrapping tightly around centre. Outflow good
all quadrants. Cyclone lies under a divergent region. Dvorak based on
wrap of 0.8 on log10 spiral yielding a DT3.5. PAT agrees but MET
still at 3.0, thus T3.5/3.5/D2.0/24hrs. Global models that have
captured this system agree on southeast acceleration with further
intensification in the next 24 to 48 hours.

FORECAST:
12hrs valid at 231800 UTC near 18.8S 153.1W mov SE 15kt with 55kt
close to centre.
24hrs valid at 240600 UTC near 21.7S 152.2W mov SSE 15kt with 60kt
close to centre.

OUTLOOK:
36hrs valid at 241800 UTC near 25.4S 151.6W mov S 20kt with 60kt
close to centre.
48hrs valid at 250600 UTC near 29.2S 152.2W mov SSW 18kt with 50kt
close to centre.

The next Tropical Disturbance Advisory on Tropical Cyclone ZITA will
be issued around 231400 UTC.

[Chacor]

426
WWSO21 ABRF 231231
IDQ20015
Australian Government Bureau of Meteorology
Queensland
Tropical Cyclone Warning Centre


SATELLITE ANALYSIS BULLETIN
1231 UTC 23 January 2007

Tropical Cyclone Zita
231200 UTC

17.3S 153.8W

Analysis based on: GOES EIR 231030 UTC.

Latitude Detection Sum : 11

Longitude Detection Sum: 17

T4.0/4.0/D1.5/24HRS

Dvorak analysis: Small system shows tight curvature. Compact CDO. CMG band wraps
0.8 on log10 spiral yielding DT 3.5 + 0.5 .

[Chacor]

WTPS12 NFFN 240000
Tropical Disturbance Advisory Number B5 issued from RSMC NADI
Jan 24/0202 UTC 2007 UTC.

TROPICAL CYCLONE ZITA 07F [985HPA] CENTRE WAS LOCATED NEAR 21.7S
151.8W AT 240000 UTC. POSITION FAIRR BASED ON HRES GOES VIS IMAGERY
WITH ANIMATION. CYCLONE MOVING SOUTH-SOUTHEAST AT 20 KNOTS. MAXIMUM
10-MINUTE AVERAGE WINDS ESTIMATED AT 50 KNOTS CLOSE TO THE CENTRE
DECREASING TO 35 KNOTS IN THE NEXT 12 HOURS. EXPECT WINDS OVER 47
KNOTS WITHIN 30 MILES OF CENTRE AND WINDS OVER 33 KNOTS WITHIN 90
MILES OF CENTRE IN THE NORTHERN SEMICIRCLE AND WITHIN 120 MILES OF
CENTRE IN THE SOUTHERN SEMICIRCLE.

EXPOSED LLCC LOCATED ABOUT 40NM NORTHWEST OF REMAINING COLD
CONVECTION. OUTFLOW GOOD FROM SOUTH TO NORTH BUT POOR ELSEWHERE.
CYCLONE CONTINUES TO MOVE INTO A STRONGLY DIVERGENT AND SHEARED
REGION. DVORAK BASED ON SHEAR PATTERN WITH DT2.5. PAT AND MET
SUPPORT, THUS T2.5/3.5/W1.0/24HRS. GLOBAL MODELS MAITAIN A MORE
SOUTHERLY TRACK WITH FURTHER WEAKENING.

FORECAST:
12HRS VALID AT 241200 UTC NEAR 25.0S 149.7W MOV SSE 19KT WITH 35KT
CLOSE TO CENTRE.
24HRS VALID AT 250000 UTC NEAR 29.5S 148.4W MOV SSE 20KT WITH 30KT
CLOSE TO CENTRE.

OUTLOOK:
36HRS VALID AT 251200 UTC NEAR 33.3S 149.2W MOV S 20KT WITH 25KT
CLOSE TO CENTRE.
48HRS VALID AT 260000 UTC NEAR 35.8S 150.6W MOV S 18KT WITH 20KT
CLOSE TO CENTRE.

THE NEXT TROPICAL DISTURBANCE ADVISORY ON TROPICAL CYCLONE ZITA WILL
BE ISSUED AROUND 240800 UTC UNLESS DOWNGRADED TO DEPRESSION BEFORE
THEN.

[Chacor]

KGWC and PGTW satfixes say extratropical.

[Chacor]

JTWC issues final advisory:

WTPS31 PGTW 240900
MSGID/GENADMIN/NAVPACMETOCCEN PEARL HARBOR HI/JTWC//
SUBJ/TROPICAL CYCLONE WARNING//
RMKS/
1. TROPICAL CYCLONE 08P (ZITA) WARNING NR 004
01 ACTIVE TROPICAL CYCLONE IN SOUTHPAC
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
---
WARNING POSITION:
240600Z --- NEAR 23.4S 151.3W
MOVEMENT PAST SIX HOURS - 165 DEGREES AT 19 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 035 KT, GUSTS 045 KT
BECOMING EXTRATROPICAL
RADIUS OF 034 KT WINDS - 110 NM NORTHEAST QUADRANT
110 NM SOUTHEAST QUADRANT
080 NM SOUTHWEST QUADRANT
080 NM NORTHWEST QUADRANT
REPEAT POSIT: 23.4S 151.3W
---
FORECASTS:
12 HRS, VALID AT:
241800Z --- 27.9S 150.9W
MAX SUSTAINED WINDS - 030 KT, GUSTS 040 KT
EXTRATROPICAL
---
REMARKS:
240900Z POSITION NEAR 24.5S 151.2W.
TROPICAL CYCLONE (TC) 08P (ZITA), LOCATED APPROXIMATELY 350 NM
SOUTH-SOUTHWEST OF TAHITI, HAS TRACKED SOUTH-SOUTHEASTWARD AT
19 KNOTS OVER THE PAST SIX HOURS. THE STORM IS COMPLETING THE
FINAL STAGES OF EXTRATROPICAL TRANSITION AHEAD OF AN APPROACHING
MIDLATITUDE TROUGH AND IS EXPECTED TO BECOME FULLY EXTRATROPICAL
BY TAU 12. RECENT ANIMATED INFRARED AND MICROWAVE SATELLITE
IMAGERY SHOW THAT ALL DEEP CONVECTION HAS SHEARED TO THE SOUTH-
EAST OF AN ELONGATING LOW LEVEL CIRCULATION CENTER. A 240559Z
SSMIS IMAGE SHOWS DRY AIR TO THE SOUTHWEST OF THE STORM WRAPPING
AROUND THE NORTHERN SEMICIRCLE AND INTO THE NORTHEASTERN QUADRANT.
THEREFORE, THIS IS THE FINAL WARNING ON THIS SYSTEM BY THE JOINT
TYPHOON WARNING CENTER (NAVPACMETOCCEN). THE SYSTEM WILL BE
CLOSELY MONITORED FOR SIGNS OF REGENERATION. MAXIMUM SIGNIFICANT
WAVE HEIGHT AT 240600Z IS 12 FEET.//

[P.K.]

First TCWC Wellington warning of the season.

GALE WARNING 238
This affects ocean area/s: PACIFIC

Cyclone ZITA [990hPa] centre was located near 25 South 150 West at
241100 UTC.
Position fair.
Repeat position 25S 150W at 241100 UTC.
Cyclone is moving south-southeast about 20 knots.
Expect sustained winds of 45 knots close to the centre decreasing to
35 knots in the next 6 to 12 hours.
Expect winds over 33 knots within 90 miles of centre in the northern
semicircle and within 180 miles of centre in the southern semicircle.

Forecast position near 30S 148W at 250000 UTC

and near 33S 146W at 251200 UTC.

This warning cancels and replaces warning 234.

[Chacor]

GALE WARNING 242
This affects ocean area/s: PACIFIC

Cyclone ZITA [995hPa] centre was located near 27.5 South 150.2 West
at
241700 UTC.
Position poor.
Repeat position 27.5S 150.2W at 241700 UTC.
Cyclone is moving south about 20 knots.
Expect sustained winds of up to 35 knots within 180 miles of centre
in southeast quadrant and within 90 miles of centre elsewhere.

Cyclone expected to become Extra-Tropical next 6-12 hours.

Forecast position near 31.5S 149W at 250600 UTC

and near 35S 150W at 251800 UTC.

This warning cancels and replaces warning 238.

[P.K.]

Zita is no more.

GALE WARNING 246
This affects ocean area/s: PACIFIC

AT 250000UTC

Low 998hPa, former Tropical Cyclone ZITA, near 29S 150W moving
southsoutheast 20kt.
Within 180 miles of low in southeast quadrant and within 90 miles of
low elsewhere: Clockwise 35kt.
Area of gales moving with low.

This warning cancels and replaces warning 242.