Tropical & EX-Tropical cyclone season 2018-19 Sth Pacific / Oz

[Nev]

I think 'Pola' in polynesian usually means a type of mat or blind made from plaited coconut fronds.

MetService had TC Pola down to Cat 3 by 8am this morning and now down to Cat 2 since around 8pm this evening. Looking a little shabby now with increasing shear taking its toll today…

[NZ Thunderstorm Soc]

I think 'Pola' in polynesian usually means a type of mat or blind made from plaited coconut fronds.

interesting?
I thought that TC or Typhoons, Hurricanes were people names, not objects.
Ah well, can't wait until Hurricane "Cardboard" forms in the Carribean Sea

[Nev]

^ Pola is also both a boy's name and family name more common in the Samoan islands...

Ex-TC Pola was declared an extratropical cyclone by MetService around 7:30am this morning.

[Cyclone Tracy]

Most ensembles showing a developing monsoon trough towards the end of this week. Also another interesting and unseasonal depression may develop north of the equator seemingly being kicked off by an equatorial Rossby wave.

The MJO phase projection gap between EC and GFS past 7 days is quite large, so lots of uncertainly where most of the deep convection will develop. EC thinks the focus will be from the Solomon Islands to the Indian Ocean with the south Pacific quiet for now. The chances of a coral sea cyclone in the next 2 weeks is increasing though.

[Cyclone Tracy]

Invest 92P has been created by JTWC for the tropical disturbance near PNG and the Solomon Islands. Both the EC ensemble and GEFS are becoming more confident of a Coral sea cyclone within the next 7 days.


Longer term GFS is showing a dangerous RI (rapid intensification) severe tropical cyclone off North Queensland.

[Cyclone Tracy]

JTWC now having invest 92S appearing on the watch map. Deep convection flared this afternoon and the low level circulation is becoming more organised. Pressure 1004 hPa, winds 15 to 20 knots.

[Nev]

TC Trevor was named by the BoM this morning…

[David]

GFS ensembles have it becoming quite intense in the Gulf of Carpentaria before second landfall

[David]

JTWC track

[Nev]

Trevor has become well organised today and is expected to intensify to a severe Cat 3 TC tomorrow before crossing Cape York's east coast in the evening.

[Cyclone Tracy]

A big hot tower erupting in the NE quadrant at the moment. Trevor is certainly gathering strength.

I love it when they get into the gulf…. its a whole new mysterious world that normally makes a mess of projections from models, met agencies and storm chasers. At the moment the gulf has 31c sea surface temps and a projected 5 to 15 knot wind shear. He has a lot going for him once he spins over that environment.

As well...UKMet latest has projected a new 907 hPa cyclonic monster off NW W.A on Saturday morning. One to keep an eye on in the next 72 hours.

[Cyclone Tracy]

Interesting Saturday of weather coming up for parts of OZ if models verify. Latest EC IR simulation projecting 2 major cyclonic gyres with pin hole eyes.

[Cyclone Tracy]

Daylight reveals Trevor is attempting to create a 'pinhole eye' and he has a very symmetrical eyewall. Generally only severe tropical cyclones show these features. BoM have him as a Cat 3 but looking at that eye and structure, developing into a cat 4 (OZ scale) at landfall could not be ruled out.

[Cyclone Tracy]

Severe TC Trevor (cat 3) is currently crossing the coast just south of Lockhart river on radar (7.30pm NZT). Lockhart River BoM site now down to 987 hPa and gusting near 100 km as it comes into the inner eyewall. The town has a population around 700 people and from all reports are well prepared.

[Thunder081]

trevor-obs.PNG

[Cyclone Tracy]

As Trevor moves closer to the Gulf to re-energise, TC Veronica is born. She also has potential to become severe in the days ahead, with a landfall quite likely around into W'A's Pilbara as a severe TC.

[David]

JTWC is picking Trevor to have sustained winds of 120 knots before landfall, this would make it a Cat 5 on the Australian scale, correct?

[Cyclone Tracy]

JTWC is picking Trevor to have sustained winds of 120 knots before landfall, this would make it a Cat 5 on the Australian scale, correct?

Good question.... the different sustained wind scales across agencies and countries is all very confusing and then they also have different levels on categories. JTWC uses the U.S method on a 1 minute max sustained winds average where Australia / Fiji / NZ / Global standard use a 10 minute sustained wind average.

120 knots on the 1 min average (JTWC) is a high end Cat 4 Oz scale, low end cat 4 US scale. To make a cat 5 OZ scale, 123 knots is the magic number to appear on JTWC.

[Cyclone Tracy]

Lowest pressure cyclones to ever be in Australian waters are TC Gwenda (1999) and TC Inigo (2003) tied @ 900 hPa. The latest GFS and UK control runs are projecting Veronica on Saturday night to be challenging this record near the W.A coastline.

[Nev]

JTWC is picking Trevor to have sustained winds of 120 knots before landfall, this would make it a Cat 5 on the Australian scale, correct?

Good question.... the different sustained wind scales across agencies and countries is all very confusing and then they also have different levels on categories. JTWC uses the U.S method on a 1 minute max sustained winds average where Australia / Fiji / NZ / Global standard use a 10 minute sustained wind average.

120 knots on the 1 min average (JTWC) is a high end Cat 4 Oz scale, low end cat 4 US scale. To make a cat 5 OZ scale, 123 knots is the magic number to appear on JTWC.

Yes, 1-minute max mean-winds are generally a little higher than 10-minute max mean-winds.
I think the WMO rough guide for converting max mean-winds is (or was?):

I-minute max mean-winds x 0.88 = 10-minute max mean-winds
10-minute max mean-winds x 1.14 = I-minute max mean-winds

So 120 kt I-minute mean-winds multiplied by 0.88 gives you 105.6 kt 10-minute mean-winds (just 1.5 kt shy of a BoM/Fiji Cat 5).

[Cyclone Tracy]

TC Trevor has been virtually stationery for the last 12 hours. His circulation is now half of water and land near Weipa. Next phase of rapid intensification will kick off tonight.

TC Veronica is currently a severe Cat 3 off W.A. Latest IR sat pic is showing frequent lightning within her inner eyewall, a sign she is now starting to mature into a very dangerous TC. Looking at her structure, environment and current behaviour, she is heading for the big league and cat 5 status.

[Cyclone Tracy]

ADT (Advanced Dvorak Technique) satellite estimating method has TC Veronica dropping from 978 to 956 hPa in the last 5 hours She is erupting. BoM has quickly upgraded her to a cat 4.

Ensembles are currently locking onto a landfall near Karratha Sunday afternoon W.A time.

[jamie]

I’m currently in WA. Very tempting to chase


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[Cyclone Tracy]

I’m currently in WA. Very tempting to chase
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You might want to buy a high grade crash helmet for this angry lady . She has now dropped 44 hPa in 24 hours and no sign of leveling at the moment.

[Thunder081]

I’m currently in WA. Very tempting to chase


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Do eetttttt