Submitted by Craig on Mon, 04/14/2014 - 13:51
South Australian Forecast (issued Friday 11th April)
Best Days: Wednesday, later Thursday on the Mid, Friday morning down South, Saturday across both coasts, Sunday morning down South, Monday on the Mid
Sunday morning was the only decent time to get a surf in across the South Coast as onshore winds relaxed enough to create clean faces with a small to moderate but peaky swell.
Today a new swell has started to show with 2ft waves across Middleton and bigger 3ft sets out at Waits as early W'ly winds provided OK conditions. Winds have since gone onshore and the Mid is still clean, but tiny.
This week and weekend (Apr 14 - 21)
A fun pulse of SW groundswell is due across the state later today ahead of a peak tomorrow morning, generated over the weekend by a mid-latitude front dipping east-southeast from below WA down towards the polar shelf.
Winds will remain less than ideal though and from the E/SE across the South Coast tomorrow morning (possibly E'ly for a period) favouring protected locations. Size wise we should see good 3ft sets at Middleton with bigger 4ft'ers out at Waits.
Wednesday is looking like the day to surf though with a fun sized but easing swell swell under morning offshores from the N/NW that should only tend light W'ly into the afternoon.
Into the end of the week we'll see the first pulse W/SW groundswell generated by a frontal system falling under the influence of the Long Wave Trough. A node of the LWT will intensify west of the Bight through the middle of this week (pictured right), supercharging and steering a series of vigorous polar fronts up through our western swell window.
This initial swell will be generated by a short-lived but intense mid-latitude low under WA, resulting in the direction being quite west in nature. This will favour the Mid Coast though, kicking up a good 1-2ft later in the day that should persist into Friday morning.
The South Coast will see more size to 2-3ft at Middleton and 3-4ft at Waits, but conditions Thursday afternoon as the swell kicks look to be bumpy with a SW breeze. Friday morning is the pick with an early W/NW'ly ahead of a strong S/SW change.
Of greater importance is a large follow up SW groundswell due on Saturday, generated by a vigorous and broad polar front firing up from the Heard Island region today before being steered by the LWT up through the Bight.
A fetch of gale to severe-gale W/SW winds will be generated through our swell window from today through until Thursday morning (pictured right), when the system will break down, generating a very large and powerful SW groundswell.
Size wise this swell should peak in the 5-6ft range across the Middleton stretch, with bigger sets out at Waits and Parsons in the vicinity of 8ft. The Mid Coast should see plenty of action as well with 2-3ft+ waves due all day.
Local winds are looking favourable but not perfect as we see relaxing pressure gradients in the wake of Friday's change. This should create variable winds on the Mid Coast while the South Coast may see a lingering SW'ly but this will only be light. Therefore breaks around Victor Harbor should be open for business.
The swell will ease into Sunday but conditions should be good across the South Coast with a morning W/NW'ly ahead of a S'ly change.
Next week onwards (Apr 21 onwards)
A moderate sized reinforcing SW groundswell is due on Monday generated by a trailing cold front behind the system responsible for Saturday's swell. This front won't be anywhere near as broad or strong as it's predecessor but it will be acting on an already active sea state, meaning it will take less work to kick up a sizey swell.
We're probably looking at Middleton hanging in the 4ft range with 4-5ft sets out at Waits, while the Mid Coast should see 1ft to occasionally 2ft sets across swell magnets. Winds will be best for the Mid and lingering from the S/SE in the wake of Sunday's change.
Longer term there's a couple of medium sized S/SW groundswells on the cards for the end of next week, but we'll look at these again on Wednesday.