The deep Tasman low near the North Island has now dissipated and left the building with a small low in the Central/Southern Tasman supplying small S swells and an even smaller trough of low pressure off the Far North Coast directing SE winds onto the coast. This pattern remains slow moving as large high slowly approaches from South of the Bight and multiple inland troughs supply unstable weather. 

The evolution of the surface low in the sub-tropics is complicated and running a little behind schedule, but as we suggested on Wed we’ll see the remnants of severe TC Lola drift into and become absorbed into the large low centre over the weekend as it approaches the North Island.

Late in the week, a combination of inland upper trough and a long angled trough extending from TC Lola remnants is expected to form a powerful surface low off the sub-tropical NSW Coast (likely between Lord Howe and Norfolk Is). As modelled, gales will produce a large E’ly quadrant swell event, with maximum size in Northern NSW, grading smaller into temperate NSW. A secondary October surprise that looks to be a major swell producer.

The synoptic set-up looks quite unseasonal at the moment with a 1031 hPa high drifting over NSW and a 1007 hPa low slow moving in the Tasman west of the North Island. Current ASCAT (satellite windspeed) passes show broad fetch of mostly strong S-S/SE winds with some embedded low end gales reasonably well aimed for East coast swell production.