TC Fili is expected to track into the slot and stall- roughly equidistant between New Caledonia, the North Island and the East Coast of Australia. At some stage it will lose intensity and become extra-tropical but even as an ex TC the overall cradling fetch of E’ly winds is going to supply days of E’ly swell.
It's a classic "Summer" looking synoptic pattern and indicative of the La Nina pattern hanging on.
That will offer a window of improving conditions at Big Wave Spots, albeit under strong offshore conditions, which will make any offshore bombies hard to ride.
A trough of low pressure associated with the current sub-tropical low deepens rapidly through tomorrow in response to the influx of cold air, forming a storm force low pressure system off the NSW Central Coast overnight Thursday into Friday.
OK, it’s going to be a wild week so lets look at the moving parts and sketch out the order of events, whilst acknowledging that it will be a highly dynamic outlook requiring fine tuning as the troughs, front, upper trough and expected eventual storm force surface low all interact.
This is then augmented by a major front pushing into the Tasman, merging with the surface low to create a large area of low pressure in the Tasman.
The trough is connected to a parent low pushing through the lower Tasman, but the combination of short period SE and longer period S swells will be marred by an onshore flow for most of this week and the weekend.
In the short run and an elongated “bubble” high sits along the NSW coast through tomorrow, bringing a cracker of a day with light offshore breezes which will tend N/NE through the day.
That front then forms a low, which becomes slow moving as it tracks NE towards the North Island. Swell is incoming from the front and the low, generating swell from the southern quadrant over the weekend and into next week.
Bit of an upgrade now for Sunday as a parent low tracks into the Tasman Friday with a much healthier fetch fetch of S to SSW winds extending through the lower Tasman.