Southern Tasmania Forecast by Ben Matson (issued Friday May 9th)

Features of the Forecast (tl;dr)

• Small new swell Sat with light winds
• Better, punchy new S'ly swell for Sun with light winds, easing Mon
• Small new swell for Tues, another maybe Wed
• Nice groundswell potential for late Fri/Sat/Sun

Recap

Continuing fun waves on offer with 2-3ft surf easing to 2ft this morning, clean conditions with light offshore winds. 

Been a good week, eh?

This weekend (May 10 - 11) 

A small reinforcing pulse is still due for Saturday will be accompanied with light variable winds. It’s not a confident swell source however I still think we’ll see a peak around the 2ft+ mark through the day. Sets will however be quite inconsistent.

Regional winds will be gusty W/NW as a front slips south of the state but inside Storm Bay we should see much lighter NW winds and better conditions.

Light winds will persist through Sunday but swing to the north, and although Saturday’s reinforcing swell will be on the way down, we have a better S/SW thru' S'ly groundswell from a polar low that developed off the ice shelf yesterday and reached maximum strength today (see below).

As I’ve mentioned all week, I really like the direction of this swell a little more for the South Arm, so we should see a nice push of energy into the region.

Wave heights should peak around 3-4ft with great waves at many beaches. It'll be well worth a look around for something to ride.

Next week (May 12 onwards)

Smaller leftover surf is expected on Monday with a weak trough expected to cross the coast late in the day. This will gradually freshen NW winds but no major strength is expected. Early morning should have some fun small waves as Sunday's swell eases back.

I’m still expecting a small long period SW swell to arrive later Monday and Tuesday, generated by a small but tight low passing near Heard Island yesterday, but without much surf size at the coast due to the large travel distance and short fetch length. So, ignore the Cape Sorell buoy when peak periods spike up to 18+ seconds. 

The latter stages of this low will track below the continent on Sunday and Monday, generating a better SW swell for Tuesday (probably the afternoon) that should boost wave heights into the 2ft range.

Another short wave trough trailing behind has been amplified in the latest model runs and is now expected to display a thin fetch of 40-50kt winds within our near swell window overnight Monday into Tuesday - though very westerly in alignment (on the northern periphery of our swell window). This may generate a small flush of swell for Wednesday but I think we may dip out on anything overly special.

The rest of the outlook period looks a little better, despite a downgrade in the synoptics since Wednesday’s forecast was issued.

A strong series of fronts currently developing below Africa will migrate throughout our swell window all week, generating an impressive fetch that will develop a lengthy swell event for the Victorian coast, arriving overnight Thursday and then pulsing at strength through Friday, Saturday and Sunday.

This is expected to provide two or three three days of waves in the 2-3ft+ range along the South Arm. 

Again, it’s still early days but it’s a very promising swell pattern ahead as we move through the last few weeks of autumn.