Severe Tropical Cyclone Fina - JTWC (22/11 PM)

From the JTWC (US) point of view, Fina is now a strong severe tropical cyclone sitting just off the coast north-east of Darwin.

At the time of this update they’ve got the centre near 11.8°S 131.4°E, about 95 km north-east of Darwin, moving west-southwest at around 7 km/h.

They estimate average winds near the centre around 150 km/h, with a tight ring in the eyewall that could be stronger again in short bursts.

Seas under the core are very rough, with waves around 9 metres.

On the Google Earth / JTWC map you’ve shared:

The red dot labelled “22/12Z – 85 knots” is the forecast position late tonight, just offshore in Beagle Gulf, west of Darwin.

The pink line is the expected track, running through the narrow gap between Melville Island and the mainland, then out into the Timor Sea.

The concentric circles around the dot show the wind zones – the inner circle is the most destructive winds near the eye, the larger circles are the broader gale area.

Darwin, Palmerston and the rural area sit inside the larger circles, meaning gales and possibly destructive gusts are expected even though the centre stays just offshore.

In simple terms, JTWC expects Fina to:

Stay over water through the channel north of Darwin and into the Timor Sea, rather than crossing directly over the city.

Peak in strength as it passes just north and west of Darwin tonight and early Sunday, still as a severe cyclone.

Then gradually weaken from late Sunday/Monday as stronger upper winds and drier air start to bite and it heads towards the Joseph Bonaparte Gulf and the Kimberley coast north of Wyndham, where it’s expected to cross the coast and fade over land.

They’re reasonably confident about the general track over the next couple of days (skirting the Top End then towards the Kimberley). The exact strength is less certain, but all guidance has it near its peak while it’s closest to Darwin, then on a clear weakening trend once it gets further west and on to land.