SPAC: Post-Tropical-WINSTON

[1900hurricane]

Using the Knaff-Zehr-Courtney wind to pressure relationship with inputs of 160 kt, 17.2 degrees from the equator, a forward speed of 10 kt, and an environmental pressure of 1008 mb (all from JTWC except for the environmental pressure, which is from ECMWF data), I ended up with a pressure of 898.5 mb.

*EDIT: and average gale force wind radius of 95 nm. That's an important parameter too.

[CrazyC83]

Using the Knaff-Zehr-Courtney wind to pressure relationship with inputs of 160 kt, 17.2 degrees from the equator, a forward speed of 10 kt, and an environmental pressure of 1008 mb (all from JTWC except for the environmental pressure, which is from ECMWF data), I ended up with a pressure of 898.5 mb.

What is the formula for that equation? Unfortunately we have no hard data at all since there are no wind readings or pressure readings in the region lately...

[1900hurricane]

Using the Knaff-Zehr-Courtney wind to pressure relationship with inputs of 160 kt, 17.2 degrees from the equator, a forward speed of 10 kt, and an environmental pressure of 1008 mb (all from JTWC except for the environmental pressure, which is from ECMWF data), I ended up with a pressure of 898.5 mb.

What is the formula for that equation? Unfortunately we have no hard data at all since there are no wind readings or pressure readings in the region lately...

Here is the Knaff-Zehr-Courtney paper. I believe it has the formula and its components broken down in there. I have a spreadsheet set up so I can easily use it.

[KatDaddy]

Incredible. TC Winston has become the strongest tropical cyclone on record in the Southern Hemisphere at 160g195 KTS which equates to 185g225 MPH.

[Yellow Evan]

Who (if anyone) is the backup for RSMC Nadi? If it can no longer function, does anyone take over, like BOM?

IIRC its the NZ Met Service.

[1900hurricane]

Looking at radar, there might actually be one very quick and discreet eyewall replacement cycle going on right now.

Link

[Exalt]

Looking at radar, there might actually be one very quick and discreet eyewall replacement cycle going on right now.

Link

HWRF had pinned (in my opinion) a bigger eye around landfall, so you may not be wrong. Sadly, it's not the good kind of pre-landfall ERC considering it only means the new Winston will restrengthen since it'll still be over water. Considering its symmetry however, is there a chance that he could go annular? I saw another member mention this earlier, and I saw it too, because at one point Winston was VERY symmetrical with little amounts of rainbands (with the only thing missing is the stadium eye to complete the donut).

[CrazyC83]

Suva goes into a island-wide curfew at 0600Z (6:00 pm local time). Other islands are likely already in such.

[Alyono]

Not anular. Annular storms typically occur over much cooler water than this.

There are plenty of rainbands associated with Winston

[Alyono]

The radar has just taken on a PERFECT appearance

[mrbagyo]

Not anular. Annular storms typically occur over much cooler water than this.

There are plenty of rainbands associated with Winston

Symmetrical might be the better term.

Suva goes into a island-wide curfew at 0600Z (6:00 pm local time). Other islands are likely already in such.

Fiji is a famous surfing spot, here's the forecast from http://www.surfline.com/
Forecast Outlook:
This forecast is primarily focused on the Mamanuca Islands (ie., Tavarua and Namotu).

SATURDAY: XL to XXL sized ESE/SE swell builds along E/SE facing exposures with gale force to cyclone force winds for regions east of the Mamanuca chain. Please prepare for landfall of TC Winston over the weekend with very dangerous and hazardous/catastrophic conditions later Saturday and into Sunday/Monday.
Tavarua is famous for its world class left known as the "Cloudbreak". I don't think someone in his right mind would even attempt to surf there during these conditions.

[StormChaser75]

930 mb from rammb goes east satellite

Now about to make landfall.....

[Alyono]

it seems to be making its closest approach to Suva now.

Nadi likely won't be as fortunate

[Alyono]

made a SW wobble, unfortunately

[StormChaser75]

it's also making landfall at Worst time, at night..

[HurricaneBill]

The 936mb pressure reading from Vanua Balavu would set a new record for lowest recorded pressure in Fiji. The previous record was 937mb measured in Yasawa during Cyclone Gavin in 1997.

[TheAustinMan]

Sustained winds of 121 mph were reported at Nambouwalu, at the southern tip of Fiji's large northern island (Vanua Levu) at 6:00 PM local time.

[supercane4867]

Literally crushing into it

[StormChaser75]

Amazing. This cyclone seems to be the "haiyan" or the new" zoe" of the south pacific Ocean ( please correct me if I am wrong as I am a noob when it comes to cyclones in the south pacific Ocean )

I hope there's not gunna be to much damage (fingers crossed ,hopefully no deaths to)

[Alyono]

The eyewall is onshore now