Eastern Tasmanian Forecast by Steve Shearer (issued Wed October 23rd)

Features of the Forecast (tl;dr)

• Easing E/NE swell Thurs with gusty W’lies
• Spike in S swell now expected Fri as low forms in Tasman
• Smal S swell leftovers Sat
• SE swell Sat PM, easing Sun
• Minor NE windswell Sun PM
• More S swell to start next week, possibly sizey as front arrives and new low forms in Tasman

Recap 

We saw a mix of mostly short range NE swells (with long range swells slowly filling in) to 2-3ft yesterday under N’ly winds before a SW-S change. Winds have shifted back N-NE today, even E/NE before swinging NW-W/NW in the a’noon. We’ve seen inconsistent 3ft sets across the beaches as long range swell fills in.

This week and next week (Oct 23- Nov1)

Weak pressure gradients in the Tasman are leading to light winds tending to N’lies as a series of troughs tracks across the interior towards the East Coast, followed by a weak high tracking at a more typical, seasonal latitude. A front is driving W’ly winds across Tasmania. We’ll see the trough and a front push into the Tasman through tomorrow and into Fri with a complex but disjointed low forming in the Tasman. That will see a S wind change and some, windy but sizey S swells through the end of the week into the weekend. Lingering troughiness in the Tasman may see yet another low form next week- which would be the 4th successive surface low to form in October. Models are struggling to resolve this complex and unstable pattern so low confidence results- but probabilistic outcomes strongly suggest another round of S swell next week from this surface low. 

In the short run we’ll see E/NE swell winding back with a few inconsistent 2 occ. 3ft sets under mod/fresh W/SW tending W/NW winds through the day.

A front brings a fresh SW tending S’ly change on Fri with a rapid spike in S swell to 4ft at S exposed breaks, which will be windy and blown out.

The weekend should see winds ease off as a trough moves NE of Tasmania. Expect some fun leftover S swell on Sat to 2-3ft easing through the day and light/variable winds. We may see some S/SE swell to 2-3ft in the a’noon from winds around the Tasman low as it drifts towards NZ.

Winds freshen from the N on Sun as the trough moves NE of Tas, with some minor NE windswell to 1-2ft and small leftover SE swell to similar size.

Bit of a roller-coaster next week as far as the outlook is concerned but models are now suggesting another broad surface low forming in lingering troughiness early next week. Triggered by a front moving into the area Mon.

Low confidence so expect revisions but at this stage we would expect a low point Mon morning with N’ly winds before short range S swell builds in the a’noon with a S’ly change.

Source of S swell Mon

Remnants of the previous low look to rebuild a fetch near the South Island over the weekend (see below) which would see quality S/SE swell through Tues into Wed, possibly as a weaker signal in a dominant building S swell as the new Tasman low winds up. 

Lots of potential outcomes depending on how this system evolves but it would be hard to imagine size less than 4ft at this stage.

We’ll pencil in another active week next week, with potential for sizey S swells and see how it looks on Fri.

Seeya then.