NW Australia: Tropical Cyclone Melanie (TC 08S)

[Ed Mahmoud]

How cold are those cloud tops?

IIRC, -80ºC or colder.

From post above with UW CIMMS ADT

Center Temp : -85.1C Cloud Region Temp : -84.1C

[CrazyC83]

Those have to be the coldest ever that I can recall for a storm of that intensity...

[CrazyC83]

Current Intensity Analysis




UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 7.2.1
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 2007DEC28 Time : 173000 UTC
Lat : 16:20:43 S Lon : 117:52:28 E


CI# /Pressure/ Vmax
3.0 / 991.0mb/ 45.0kt


6hr-Avg T# 3hr-Avg T# Adj T# Raw T#
3.0 3.1 3.2 3.8

Latitude bias adjustment to MSLP : +0.0mb

Center Temp : -86.2C Cloud Region Temp : -87.2C

Scene Type : UNIFORM CDO CLOUD REGION

Positioning Method : FORECAST INTERPOLATION

Ocean Basin : INDIAN
Dvorak CI > MSLP Conversion Used : PACIFIC

Tno/CI Rules : Constraint Limits : 0.7T/6hr
Weakening Flag : OFF
Rapid Dissipation Flag : OFF

[HURAKAN]

Australian Government Bureau of Meteorology
Western Australia

Media: The Standard Emergency Warning Signal should NOT be used with this
warning.

PRIORITY

TROPICAL CYCLONE ADVICE NUMBER 3
Issued at 4:00 am WDT on Saturday, 29 December 2007
BY THE BUREAU OF METEOROLOGY
TROPICAL CYCLONE WARNING CENTRE PERTH

A Cyclone WATCH has been declared for coastal areas from Exmouth to Broome.

At 3:00 am WDT Tropical Cyclone Melanie, Category 1 was estimated to be
540 kilometres west northwest of Broome and
560 kilometres north of Port Hedland and
moving south at 7 kilometres per hour towards the coast.

Tropical Cyclone Melanie is not expected to cause gales on the coast today.
However gales may develop on the coast on Sunday.

Details of Tropical Cyclone Melanie at 3:00 am WDT:
.Centre located near...... 15.3 degrees South 118.0 degrees East
.Location accuracy........ within 55 kilometres
.Recent movement.......... towards the south at 7 kilometres per hour
.Wind gusts near centre... 120 kilometres per hour
.Severity category........ 1
.Central pressure......... 980 hectoPascals

FESA-State Emergency Service advises that there are no community alerts at
present.
Residents in coastal communities between Broome and Exmouth should listen for
the next advice.
The next advice will be issued by 10:00 am WDT Saturday 29 December.
Cyclone advices and State Emergency Service Community Alerts are available by
dialling 1300 659 210

A map showing the track of the cyclone is available at:
http://www.bom.gov.au/weather/wa/cyclone

[CrazyC83]

Eyewall forming per NRL analysis...

[CrazyC83]

Best shot yet, clear signs that it is developing an eye:



I'd say 55 kt (1-min)/985mb personally right now.

[Cyclone1]

Dude... that IR shot on Page 2 is off the scale! I remember it hitting dark gray with Noel but not like that.

[CrazyC83]

Current Intensity Analysis




UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 7.2.1
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 2007DEC28 Time : 193000 UTC
Lat : 16:33:33 S Lon : 117:46:18 E


CI# /Pressure/ Vmax
3.2 / 988.2mb/ 49.0kt


6hr-Avg T# 3hr-Avg T# Adj T# Raw T#
3.2 3.2 3.3 3.8

Latitude bias adjustment to MSLP : +0.0mb

Center Temp : -80.4C Cloud Region Temp : -83.1C

Scene Type : UNIFORM CDO CLOUD REGION

Positioning Method : FORECAST INTERPOLATION

Ocean Basin : INDIAN
Dvorak CI > MSLP Conversion Used : PACIFIC

Tno/CI Rules : Constraint Limits : 0.7T/6hr
Weakening Flag : OFF
Rapid Dissipation Flag : OFF

[CrazyC83]

WTXS31 PGTW 282100
MSGID/GENADMIN/NAVPACMETOCCEN PEARL HARBOR HI//
SUBJ/TROPICAL CYCLONE WARNING//
RMKS/
1. TROPICAL CYCLONE 08S (MELANIE) WARNING NR 003
01 ACTIVE TROPICAL CYCLONE IN SOUTHIO
MAX SUSTAINED WINDS BASED ON ONE-MINUTE AVERAGE
---
WARNING POSITION:
281800Z --- NEAR 15.7S 118.1E
MOVEMENT PAST SIX HOURS - 195 DEGREES AT 04 KTS
POSITION ACCURATE TO WITHIN 060 NM
POSITION BASED ON CENTER LOCATED BY SATELLITE
PRESENT WIND DISTRIBUTION:
MAX SUSTAINED WINDS - 045 KT, GUSTS 055 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 055 NM NORTHEAST QUADRANT
060 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
REPEAT POSIT: 15.7S 118.1E
---
FORECASTS:
12 HRS, VALID AT:
290600Z --- 16.9S 117.5E
MAX SUSTAINED WINDS - 050 KT, GUSTS 065 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 034 KT WINDS - 065 NM NORTHEAST QUADRANT
070 NM SOUTHEAST QUADRANT
065 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
VECTOR TO 24 HR POSIT: 225 DEG/ 07 KTS
---
24 HRS, VALID AT:
291800Z --- 17.9S 116.4E
MAX SUSTAINED WINDS - 055 KT, GUSTS 070 KT
WIND RADII VALID OVER OPEN WATER ONLY
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 - 075 NM NORTHEAST QUADRANT
075 NM SOUTHEAST QUADRANT
075 NM SOUTHWEST QUADRANT
065 NM NORTHWEST QUADRANT
VECTOR TO 36 HR POSIT: 240 DEG/ 08 KTS
---
36 HRS, VALID AT:
300600Z --- 18.6S 115.0E
MAX SUSTAINED WINDS - 065 KT, GUSTS 080 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 050 KT WINDS - 045 NM NORTHEAST QUADRANT
045 NM SOUTHEAST QUADRANT
045 NM SOUTHWEST QUADRANT
045 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 095 NM NORTHEAST QUADRANT
095 NM SOUTHEAST QUADRANT
095 NM SOUTHWEST QUADRANT
085 NM NORTHWEST QUADRANT
VECTOR TO 48 HR POSIT: 255 DEG/ 07 KTS
---
EXTENDED OUTLOOK:
48 HRS, VALID AT:
301800Z --- 19.0S 113.5E
MAX SUSTAINED WINDS - 075 KT, GUSTS 090 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 025 NM NORTHEAST QUADRANT
025 NM SOUTHEAST QUADRANT
025 NM SOUTHWEST QUADRANT
025 NM NORTHWEST QUADRANT
RADIUS OF 050 KT WINDS - 055 NM NORTHEAST QUADRANT
055 NM SOUTHEAST QUADRANT
055 NM SOUTHWEST QUADRANT
055 NM NORTHWEST QUADRANT
RADIUS OF 034 KT WINDS - 110 NM NORTHEAST QUADRANT
120 NM SOUTHEAST QUADRANT
120 NM SOUTHWEST QUADRANT
105 NM NORTHWEST QUADRANT
VECTOR TO 72 HR POSIT: 265 DEG/ 04 KTS
---
72 HRS, VALID AT:
311800Z --- 19.1S 111.6E
MAX SUSTAINED WINDS - 080 KT, GUSTS 100 KT
WIND RADII VALID OVER OPEN WATER ONLY
RADIUS OF 064 KT WINDS - 030 NM NORTHEAST QUADRANT
030 NM SOUTHEAST QUADRANT
030 NM SOUTHWEST QUADRANT
030 NM NORTHWEST QUADRANT
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
130 NM SOUTHEAST QUADRANT
130 NM SOUTHWEST QUADRANT
120 NM NORTHWEST QUADRANT
---
REMARKS:
282100Z POSITION NEAR 16.0S 118.0E.
TROPICAL CYCLONE (TC) 08S (MELANIE), LOCATED APPROXIMATELY 270 NM
NORTH OF PORT HEDLAND, AUSTRALIA, HAS TRACKED SOUTH-SOUTHWESTWARD
AT 04 KNOTS OVER THE PAST 06 HOURS. THE INITIAL POSITION IS BASED
ON SATELLITE FIXES FROM PGTW AND APRF AND A 281715Z AMSR-E PASS.
DVORAK T-NUMBERS OF 3.0/3.0 FROM BOTH PGTW AND APRF YIELD AN
INITIAL INTENSITY ESTIMATE OF 45 KNOTS. TC 08S CONTINUES TO TRACK
TOWARD THE NORTHWESTERN COAST OF AUSTRALIA ALONG A LOW TO MID-
LEVEL RIDGE EXTENSION TO THE EAST OF THE STORM. HOWEVER, THE
WESTWARD COMPONENT OF STORM MOTION IS EXPECTED TO INCREASE THROUGH
THE FORECAST PERIOD AS DEEP LAYER SUBTROPICAL RIDGING TO THE SOUTH
OF THE SYSTEM IMPARTS AN INCREASING STEERING INFLUENCE. THE PERI-
PHERAL FLOW ASSOCIATED WITH AN UPPER LEVEL, SYNOPTIC-SCALE ANTI-
CYCLONE CENTERED EAST OF TC 08S CONTINUES TO IMPACT THE STORM BY
INTRODUCING NORTHEASTERLY VERTICAL WIND SHEAR. HOWEVER, GOOD POLE-
WARD OUTFLOW AND HIGH OCEAN HEAT CONTENT WILL SUPPORT INTENSIFICA-
TION DESPITE THIS SHEAR. THE INTENSIFICATION RATE IS FORECASTED
TO INCREASE AFTER TAU 24 AS UPPER LEVEL OUTFLOW FROM THE SYSTEM
PROVIDES A STRONGER BUFFER AGAINST THE SHEARING FLOW. AFTER TAU 48,
DECREASING POLEWARD OUTFLOW SHOULD AGAIN REDUCE THE STORM'S CAPA-
CITY TO SIGNIFICANTLY INTENSIFY. THE AVAILABLE OBJECTIVE AIDS ARE
IN GOOD, GENERAL AGREEMENT WITH BOTH THE TRACK AND INTENSITY
FORECASTS. MAXIMUM SIGNIFICANT WAVE HEIGHT AT 281800Z IS 16 FEET.
NEXT WARNINGS AT 290300Z, 290900Z, 291500Z AND 292100Z.//

NNNN

45 kt per JTWC - quite conservative IMO...

[CrazyC83]

Pinhole eye forming?

[Coredesat]

Not exactly a pinhole, but that is an eye.

[CrazyC83]

UW-CIMSS Automated Satellite-Based
Advanced Dvorak Technique (ADT)
Version 7.2
Tropical Cyclone Intensity Estimation Algorithm


Current Intensity Analysis




UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 7.2.1
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 2007DEC28 Time : 223000 UTC
Lat : 16:10:24 S Lon : 117:56:00 E


CI# /Pressure/ Vmax
3.4 / 986.6mb/ 53.0kt


6hr-Avg T# 3hr-Avg T# Adj T# Raw T#
3.4 3.4 3.6 3.9

Latitude bias adjustment to MSLP : +1.2mb

Center Temp : -85.6C Cloud Region Temp : -85.8C

Scene Type : UNIFORM CDO CLOUD REGION

Positioning Method : FORECAST INTERPOLATION

Ocean Basin : INDIAN
Dvorak CI > MSLP Conversion Used : PACIFIC

Tno/CI Rules : Constraint Limits : 0.7T/6hr
Weakening Flag : OFF
Rapid Dissipation Flag : OFF

[HURAKAN]

Melanie shows its power.

[CrazyC83]

There is a well-defined eye beneath there according to NRL images. I'd say 65 kt (1-min) right now.

[P.K.]

Upgraded to a cat 2.

FKAU03 ADRM 290040
TC ADVISORY
DTG: 20071229/0000Z
TCAC: DARWIN
TC: MELANIE
NR: 05
PSN: S1642 E11800
MOV: S 06KT
C: 974HPA
MAX WIND: 50KT
FCST PSN +6HR: 29/0600 S1724 E11800
FCST MAX WIND +6HR: 55KT
FCST PSN +12HR: 29/1200 S1800 E11800
FCST MAX WIND +12HR: 60KT
FCST PSN +18HR: 29/1800 S1836 E11748
FCST MAX WIND +18HR: 70KT
FCST PSN +24HR: 30/0000 S1906 E11730
FCST MAX WIND +24HR: 70KT
NXT MSG: 20071229/0700Z

[HURAKAN]

Australian Government Bureau of Meteorology
Western Australia

Media: The Standard Emergency Warning Signal should NOT be used with this
warning.

TOP PRIORITY FOR IMMEDIATE BROADCAST

TROPICAL CYCLONE ADVICE NUMBER 4
Issued at 9:50 am WDT on Saturday, 29 December 2007
BY THE BUREAU OF METEOROLOGY
TROPICAL CYCLONE WARNING CENTRE PERTH

A Cyclone WARNING has been declared for coastal areas from Mardie to Wallal
including Port Hedland and Karratha-Dampier.

A Cyclone WATCH has been declared for remaining coastal parts between Broome and
Coral Bay, extending inland to include Nanutarra and Marble Bar.

At 9:00 am WDT Tropical Cyclone Melanie, Category 2 was estimated to be
410 kilometres north of Port Hedland and
465 kilometres north northeast of Karratha and
moving south at 11 kilometres per hour towards the coast.

Gales with gusts to 120 kilometres per hour are possible on the coast between
Mardie and Wallal, including Karratha and Port Hedland, on Sunday as the cyclone
moves closer to the coast. Widespread heavy rain is likely in coastal parts of
the Pilbara from Sunday.

Details of Tropical Cyclone Melanie at 9:00 am WDT:
Centre located near...... 16.7 degrees South 118.0 degrees East
Location accuracy........ within 85 kilometres
Recent movement.......... towards the south at 11 kilometres per hour
Wind gusts near centre... 130 kilometres per hour
Severity category........ 2
Central pressure......... 974 hectoPascals

FESA-State Emergency Service advises that there are no community alerts at
present. Residents of coastal and adjacent inland communities between Broome and
Coral Bay should listen for the next advice.
The next advice will be issued by 1:00 pm WDT Saturday 29 December.
Cyclone advices and State Emergency Service Community Alerts are available by
dialling 1300 659 210

A map showing the track of the cyclone is available at:
http://www.bom.gov.au/weather/wa/cyclone

[HURAKAN]

Now forecasted to get much closer to the coast. Direct impact seens real possible.

[CrazyC83]

Now forecasted to get much closer to the coast. Direct impact seens real possible.

Yep, now a Cyclone Warning issued.

[Coredesat]

AXAU01 APRF 290119
IDW27600
TROPICAL CYCLONE TECHNICAL BULLETIN: AUSTRALIA - WESTERN REGION
Issued by PERTH TROPICAL CYCLONE WARNING CENTRE
at: 0119 UTC 29/12/2007
Name: Melanie
Data At: 0000 UTC
Latitude: 16.7S
Longitude: 118.0E
Location Accuracy: within 45 nm [85 km]
Movement Towards: south [180 deg]
Speed of Movement: 6 knots [11 km/h]
Maximum 10-Minute Wind: 50 knots [95 km/h]
Maximum 3-Second Wind Gust: 70 knots [130 km/h]
Central Pressure: 974 hPa
Radius of 34-knot winds NE quadrant:
Radius of 34-knot winds SE quadrant:
Radius of 34-knot winds SW quadrant:
Radius of 34-knot winds NW quadrant:
Radius of 48-knot winds NE quadrant:
Radius of 48-knot winds SE quadrant:
Radius of 48-knot winds SW quadrant:
Radius of 48-knot winds NW quadrant:
Radius of 64-knot winds:
Radius of Maximum Winds:
Dvorak Intensity Code: T3.0/3.0/D1.0/24HRS
Pressure of outermost isobar: 998 hPa
Radius of outermost closed isobar: 240 nm [445 km]
Storm Depth: Deep
FORECAST DATA
Date/Time : Location : Loc. Accuracy: Max Wind : Central Pressure
[UTC] : degrees : nm [km]: knots[km/h]: hPa
+12: 29/1200: 18.0S 118.0E: 075 [140]: 060 [110]: 964
+24: 30/0000: 19.1S 117.5E: 100 [185]: 070 [130]: 956
+36: 30/1200: 19.9S 116.7E: 130 [240]: 080 [150]: 944
+48: 31/0000: 20.4S 116.0E: 150 [280]: 085 [155]: 942
+60: 31/1200: 20.9S 115.3E: 185 [345]: 085 [155]: 944
+72: 01/0000: 21.4S 114.4E: 220 [405]: 080 [150]: 946
REMARKS:
Melanie has continued to intensify at the standard rate under relatively
favourable shear conditions with a good outflow channel to the south. Shear
conditions are forecast to be neutral to favourable in the next 24/48 hours and
hence continued development is expected. If the system does track to the
southwest as forecast by most models then upper intensity should be limited by
continuation of some shear over the system.

System is expected to maintain a general southerly track in next 12-18 hours and
then become more southwesterly. However although there is generally good
agreement between the models regarding a southwesterly movement there is a
significant risk that the sytem will maintain a more southerly track than
indicated by a non-selective consensus. The ridge to the south is narrow and a
weakness appears during the next 24-36 hours as a trough passes to the south.
Furthermore the models develop an upstream mid level low for which there is
currently no observational support, and the existence of which will have
downstream impacts on the environment of the TC. Finally if the system does
continue to develop and establishes a peripheral ridge to the northeast this
will encourage a more southerly movement. A more southerly movement will provide
a more favourable shear environment. Warning policy is therefore emphasising the
risk of a severe impact on the coast.
==
The next bulletin for this system will be issued by: 29/0700 UTC by Perth TCWC.

[Cyclenall]

Melanie is in the top 10 coldest cloud tops for TC's that I've seen. -85C is not very common and I have only seen that a few times before. -80C is much more common but still "rare" (not for these basins).

I think it will for a tiny eye but not a pinhole. Classic RI as usual for these regions can occur soon.