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Coupla peaky swells, but with tricky winds throughout

Eastern Tasmania Surf Forecast by Ben Matson (issued Thursday 15th October)

Best Days: Thurs thru' Sun: peaky mix of alternating NE windswells (biggest Thurs PM, Sat PM) and small underlying S swells, though with tricky winds. 

This week (Oct 13 - 16)

A developing N/NE fetch from Tasmania up to Southern NSW is generating building NE swells right now, though it’ll be a short lived event thanks to an approaching front that will push the fetch our of our swell window through today. Size should reach the 3ft mark at exposed beaches sometime this afternoon and we should see a period of variable winds this afternoon just ahead of an evening SW change. 

We’ve got a couple of additional swells on the way. A small long period S’ly swell will build today too, sourced from an intense though poorly aligned polar below the continent earlier this week. Additionally, this evening’s front will have a decent fetch trailing behind so although poorly aligned, should generate 3ft of south swell at south swell magnets into Friday.

Local conditions will be at risk of an early fresh southerly breeze (in the wake of tonight’s change) but the good news is that the front will quickly clear to the east and we should see lighter winds into the afternoon, along with a mix of decent south swell and rapidly easing NE swell.

This weekend (Oct 17 - 18)

A new trough of low pressure crossing the Victorian region on Friday will slowly evolve a new surface low east of Tasmania on Saturday.


The low looks like it’ll be positioned a little too far to the north and will track too fast to the east to favourably influence our surf potential (once it develops) but prior to then - late Friday and into Saturday - a local NE fetch just upstream should generate 3ft of peaky NE swell throughout Saturday, peaking into the afternoon. 

Local conditions are somewhat unsure though.

Early Saturday will be at risk of a lingering northerly flow, but as the trough pushes offshore, we’ll see a period of variable conditions and then a swing in the wind direction to the south. The concern right now is that the low may be positioned a little further north (i.e. east of Bass Strait) and instead of a window of variable winds, we instead pick up an easterly breeze on the trough’s southern flank.

I’ll have more idea on this over the coming days, but at least there’s no concern for surf - there’ll be plenty. Also in the water over the weekend will be a small south swell, source from an earlier incarnation of the parent (polar) low to tonight’s southerly change, well south of the continent at the moment.

Lingering, easing southerly winds in the wake of this system on Sunday should slowly improve conditions and we’ll see easing a mix of easing swells from the NE thru' E/NE and S across the region. There'll be fun waves if you can find a protected southern corner.

Next week (Oct 19 onwards)

Looks like the Tasman Sea will support a broad, slow moving troughy pattern throughout next week, resulting in the development of centre low pressure centres. However, current indications are that they’ll probably be better aimed towards NSW and SE Qld regions. In particularly, the weekend's trough-cum-Tasman-Low looks favourably positioned in individual synoptic snapshots (see below), but unfortunately its eastern trajectory significant diminishes its swell potential for the start of next week.

As such our long range surf potential looks to be a series of flukey southerly swells from poorly aligned fronts, resulting in generally small options. Model guidance is suggesting some punchy local NE swell later next week and into the weekend, but it’s a long time away and I’m not confident on the source. 

More on this in Friday’s update. 

Comments

uncle-swap's picture
uncle-swap's picture
uncle-swap commented Sunday, 18 Oct 2020 at 1:28pm

Thanks for the detailed report Craig, wondering when the next detailed forecast for this location will be updated?
Many thanks

uncle