Eastern Tasmania Surf Forecast by Steve Shearer (issued Mon 4th Sep)

Features of the Forecast (tl;dr)

•  NE windswell  easing Tues with winds tending offshore
• Small E swell in the mix Mon/Tues
• Another round of NE windswell Thurs
• Steep increase in sizey S swell Fri with fresh SW-SSW winds
• Plenty of S swell Sat, with a fresh increase likely Sun
• S swells likely through to mid next week 

Recap

Minor swells for Sat with Sun seeing a mix of small E/SE and building NE swells to 2ft. Today has seen a further increase in NE windswell to 3-4ft with fresh NE winds.

This week and next (Sep4 - Sep15)

The weekend’s low pressure system is still lingering near New Zealand, with the merger of the low with a tropical derived low not really happening. The expected Cook Strait fetch is still looking OK though and in fact is better aimed at Tasmania and still a significant swell source for the region. A pair of fronts from tomorrow race away quickly with a small spike of S swell expected. The following system expected Fri this week now looks much stronger and under current modelling is expected to be a significant source of sizey S swell, potentially with several large pulses. Let’s look at the details.

In the short run get in early tomorrow for NE windswell to 3ft with offshore winds. Size eases through the day as the fetch is shunted away and we’ll see winds shift more SW in the a’noon and freshen.

Winds shift back to the NW on Wed ands we should see a surfable mixed bag of small NE swell and some E’ly swell from the Cook Strait source to 2ft. 

Freshening N’lies on Thurs then see NE windswell building to 2-3ft during the day. Winds should tend more NNW-NW in the a’noon, offering up a window of improving conditions before dark. 

Expect revisions as we move through the week but under current modelling a front/low/trough combo forms a a long angled fetch in the lower Tasman as the low moves away, with a proximate fetch of near gales to the Tasmanian coast as a long trough and low form in the Tasman. That should see a rapid building trend in S swell on Fri, with fresh SSW winds. Expect size to build into the 6-8ft range during the day, smaller at more protected locations.

Plenty of S swell Fri if this chart comes off as modelled

Into the weekend and plenty of S swell for Sat, although coming off Fridays peak with size likely in the 3-5ft range, easing during the day and favourable offshore winds developing.

Another front Sun is likely to see a fresh pulse build in during the day, into the 4ft range with S/SE swell  to 3-4ft from the deeper fetch in the Tasman. W’ly winds look to tend more SW as the secondary front pushes through.

Sizey S swell likely continues early next week, possibly sizey, as another front enters the Tasman, reinforcing the existing long trough/low and potentially forming a new low. Under EC modelling the reinforced low sits in the Tasman, offering up elevated wave heights for most of next week, likely peaking Mon/Tues in the 4-5ft range.

GFS has a slightly less persistent system, with the new front bringing a large pulse of S swell Mon/Tues into the 4ft range and a slow easing into Wed. 

With broad model agreement odds are firming we’ll see a significant S swell event this Fri/weekend and into early/mid next week with plenty of S’ly wind. Still a ways to go though before this storm forms, so check back in on Wed and we’ll run the ruler over it again.

Seeya then.