A strong, but decaying cold front tied to a mid-latitude low is pushing gales through a wide swathe of the lower Tasman, with a handy S swell now being generated for the region. A relatively weak high (1025hPa) is pushing though the Bight with a transitory ridge, quickly breaking down and tending N’ly mid week , before another mid-latitude low pushes through and brings a NW to W’ly flow across the weekend.

The Tasman low is out of the swell window and a large high is now moving over Tasmania to take up position in the Tasman Sea at a southerly latitude typical of the high pressure belt under the La Niña phase of the ENSO cycle. The high will move E with a N’ly flow rapidly developing as pressure gradients get tightened by an approaching front, complex low and trough line.

Complex and dynamic weekend ahead, with an upper trough, surface trough and front forming a surface low in the convergence off the North Coast. The initial front now feeds into a deepening trough line off the Mid North Coast (separate to the developing surface low off the North Coast ) which amplifies the fetch of S/SE winds adjacent to the Central NSW Coast.

Not a great deal of action on the charts to start the last week of Winter. A strong high (1040hPa)  is on the other side of New Zealand but pressure gradients in the Tasman are weak, with minimal swell energy being generated from that source. N’ly winds are freshening ahead of a trough which is drawing down more moisture from the Indian Ocean and brings a  S’ly change mid-week and a small pulse in S swell.