South Oz Forecast by Ben Matson (issued Wednesday November 6th)

Features of the Forecast (tl;dr)

• Fun waves early Thursday at Victor with offshore winds
• Great waves across both coasts Saturday with a powerful swell and generally light winds
• Strong surf persisting Sunday though SE winds are risk (for Victor.. it'll remain good on the Mid)
• Onshore winds will create problems down south early next week
• Another strong swell later next week though likely best suited to Victor

Recap

Easing surf on Tuesday offered inconsistent 2ft surf on the Mid Coast and 2-3ft surf at Middleton, clean with early winds. Size then eased into the afternoon. An onshore change pushed across the coast this morning, and we saw a temporary dip in wave heights owing to the late arrival of a small new groundswell that’s now showing bumpy 1-2ft sets on the Mid with similarly wobbly 2-3ft waves at Middleton.

This week (Nov 7 - 8)

Another front will cross the coast on Thursday, probably around lunchtime or early afternoon, but ahead of it we’ll see light NW winds at dawn freshening quickly mid-late morning - allowing for clean conditions at Victor but deteriorating surface conditions along the Mid Coast.

As for surf size, even though the swell expected to arrived today is running quite late (sourced from a polar low below Heard Island over the weekend), there’s no reason to discount its size potential, so we should see a continuation of 1-2ft waves along the Mid in the morning (chance for a brief window of clean waves at dawn, though bear in mind the early high tide) with some additional windswell on top into the afternoon.

Middleton should offer inconsistent 2-3ft sets on Thursday morning. Get in early before the wind swings onshore. 

Friday has yet another frontal passage due to push through during the morning, and it’ll be stronger than Thursday’s. We should see underlying 1-2ft of groundswell on the Mid Coast bump up to 3-4ft into the afternoon in the wake of the front, with a bumpy mix of energy creating a somewhat confused sea state. It won’t be quite a proper stormy but there is a chance for a few small waves on the metro beaches. 

Down south, chances for an early window of cross-offshore winds are low on Friday, so anticipate below-average conditions as surf size builds from 2-3ft at Middleton early to 3-5ft late. 

This weekend (Nov 9 - 10)

The weekend is looking very promising, with lots of potential for quality surf. 

Friday’s front will clear quickly to the east overnight and winds should become light and variable across both coasts. A weak high pressure system will start to ridge in from the west on Saturday, and may bring about a shallow SE wind change late Saturday, though it’s not expected to show any major strength until Sunday afternoon (I'll update these thoughts on Friday, though). 

Regardless, the threat of SE winds (at Victor) will remain present through this time, so if you’re looking to surf down south, make Saturday morning a priority.

Local winds aside, it’s the surf potential we are most interested in. 

Friday’s front will have displayed a large, slow moving fetch behind it for a few days prior (see below) and that will have generated a strong swell that’s expected to build to 4-6ft across the South Coast, maybe even some bigger sets at the regional swell magnets and offshore bombies nudging 6ft to maybe 8ft. A peak in size is expected late Saturday; early Sunday should still be very strong though there will be a downwards trend through the day.

Fortunately, this swell is also looking good for the Mid Coast too. It wasn't perfectly aligned within the gulf's swell window, but the sheer strength, width and length of the fetch should allow for 2-3ft sets both days, with Saturday afternoon's tidal push possibly delivering some bigger bombs at the swell magnets. Expect a slight easing through Sunday.

Next week (Nov 11 onwards)

Further polar activity related to the tail end of this frontal sequence will continue to produce strong though easing swells into Monday for the South Coast, however S/SE winds will start to freshen during this time in response to a strengthening high pressure system to the west. 

These polar developments will be outside of the Mid Coast’s swell window so expect a slow easing of surf size in the gulf (local winds should be favourable through the mornings though).

Otherwise, the long term outlook has also had an improvement since Monday’s notes were written.

We’ll see easing size through Tuesday and Wednesday however another strong Southern Ocean low is now expected to move through our swell window around the same time, setting up a strong swell for Thursday or Friday. This system looks better positioned for the South Coast than the Mid Coast but either way it’s a nice outlook to work towards. 

I’ll have more on that in Friday’s update.