Eastern Tasmanian forecast by Steve Shearer (issued Wed March 26th)

Features of the Forecast (tl;dr)

• Building S/SE windswell late Sat with S’ly winds
• Surf building further Sun as low moves towards Tasmania- large swells with fresh SE winds
• Surf remaining large into Mon, easing into Tues/Wed with offshore winds

Recap

Inconsistent S/SE groundswell yesterday supplied clean 2-3ft surf in the morning before easing as N/NE winds freshened. Only tiny leftovers to 1-1.5ft today with SW tending S/SE through the day and a very tiny S/SE windswell behind it.

This week and next week (Mar 26 - Apr 4)

A major tropical event is unfolding as an active phase of the MJO sparks a late season monsoonal surge. That is seeing a monsoon trough stretched across the continent with a TC in the Indian Ocean well offshore from the Pilbara, a monsoonal low inland of the NT/QLD border and monsoonal activity in the Coral Sea. It’s likely we will see remnants of the inland monsoon low approach the SEQLD/NSW Coast during the weekend, dragging a moist NE flow down from the tropics and creating a mini black nor-easter event. We’ll see surf from this NE-E/NE infeed propagate from the sub-tropics down to temperate regions over the weekend, eventually generating swells for NETas as a surface low forms from the trough off the south coast of NSW and moves towards Bass Strait. Lots of action ahead with this  dynamic pattern so keep tabs because there will be revisions as we get closer to the event.

Nothing much short term while we wait for the event to unfold and high pressure moves across the Island. Expect tiny surf through tomorrow with traces of just rideable NE windswell possible Fri a’noon as N-NE winds increase adjacent to the Island and extend up into Bass Strait.

A trough Sat brings a gusty S’ly change and some new S’ly windswell through the a’noon to 3-4ft.

Things get much juicier Sun as that trough conjoins with the tropical trough exiting the coast north of Gippsland and forms a more robust surface low. 

That should see winds freshen from the SE with a building combination of E/NE and S/SE-SE swells - size should reach 5-6ft through the a’noon but surfable waves will require maximum wind protection. 

By Mon we should see the low positioned NE of the island (see below) with gales in two quadrants generating large SE to E swells and strong S’ly winds.

Source of large swells late in the weekend, early next week

Size could be in the 6-8ft range or even bigger depending on how the low evolves and where it’s located - we’ll revise on Fri.

Surf then eases into mid next week as the low moves away from the Island.

Check back Fri for the latest.