Active Tasman sea with swell from the NE and ENE incoming
Eastern Tasmania Surf Forecast by Steve Shearer (issued Mon 30th August)
Features of the Forecast (tl;dr)
- New E swell pulse Thurs, easing through Fri with NW to N winds.
- NE windswell building next Fri, easing quickly through Sat AM
- ENE swell building Mon/Tues next week
- S swell likely Mon next week, uncertain outlook, stay tuned for details
Plenty of ESE swell over the weekend from a slow moving Tasman low drifting towards New Zealand. Saturday saw the biggest surf with 4-6ft surf at exposed places and light SE winds. Size dropped into the 3-4ft range Sun with light N’ly winds. Swells have eased right back today into the 2-3ft range with a light NE breeze not affecting surface conditions too much.
This week and weekend (Aug 30- Sep 5)
An active week ahead as a major pattern change takes place indicative of a shift towards a La Nina phase of the ENSO cycle. High pressure in the Tasman moves SE and takes up position this side of the North Island, becoming half of the “peanut” high straddling the North Island. This incredible high pressure system, 1036 and 1042 hPa, then begins to extend a long, broad fetch of SE/ESE winds adjacent to the North Island and extending through the South Pacific and into the Northern Tasman and Southern Coral Sea. This portends another extended E’ly swell event, more focussed on NENSW and SEQLD but with enough width in the fetch to ensure the entire NSW coast and down to Tasmania gets sprayed with swell from the Eastern Quadrant.
N’ly winds coming down the back of the high also invigorate several N’ly fetches this week with subsequent NE wind swells being generated for NETas.
The first builds later Tuesday as N’ly winds freshen down the south coast and into Bass Strait. Fresh N’ly winds accompany a rising NE windswell with size building into the 3ft range in the PM. Winds are expected to tend NW to NNW late in the day, offering some cleaner options in northern corners.
This drops quickly Wed as a front passing to the south of Tasmania shunts the fetch E’wards and winds tend WNW before quickly tending N’ly again.
N’ly winds then freshen again Thursday with a much stronger fetch adjacent to the NSW coastline and extending down to the Tasmanian coast brings a stronger flush of NE windswell. This builds later Thursday into the 3ft range, building further o’night to be in the 4-5ft range during Fri. Winds tend NW on Fri before a likely SW to S’ly change during the day. Expect a small amount of E’ly swell Thursday from the Cook Strait fetch we mentioned on Fri, which will add some 2ft sets from the ENE.
This N’ly fetch is unusually resilient, maintaining position during Fri off the NSW Coast so we can expect a lot more residual energy to hold during Sat, in the 3-4ft range and even Sun, in the 2-3ft range.
Winds are likely to tend W through SW Sat, before tending S’ly on Sun.
Stay tuned for revision on that as models are showing a lot of divergence at the moment.
Longer term and swell from the E’ly fetch extending into the Northern Tasman Sea is expected to be broad enough to extend down to the East Coast of Tasmania, although at lower levels. We should see ENE swell start to show in the 2-3ft range early Mon, building into the 3ft range by close of play and muscling up a notch into Tuesday. Wind outlook is uncertain but likely to be strong SW/S so check back in on Wed for a closer look at that.