Victoria Forecast by Craig Brokensha (issued Wednesday 5th March)
Best Days: Sunday, early Monday at exposed breaks, Thursday/Friday next week
Both coasts saw great waves on the beaches yesterday with an easing but fun SW groundswell under offshore N'ly winds. Conditions remained clean into the afternoon as well as favourable winds persisted.
Early this morning conditions were still clean with a light offshore breeze across most locations, but a fresh to strong S/SW change moved in just after dawn, writing off the surf for the rest of the day.
This week (Mar 5 -7)
Rest up for the weekend over the coming days, as although we'll see a good new pulse of W/SW groundswell tomorrow, winds will be poor and fresh from the southern quadrant.
This weekend onwards (Mar 8 onwards)
As touched on the last two updates, a strong but distant SW groundswell is due to arrive Saturday afternoon, peak overnight and ease slowly Sunday under great winds.
The source of this swell is a vigorous polar low that fired up just west of Heard Island at the start of the week and has since moved east along the polar shelf while slowly weakening. The system is now south-southwest of WA and will continue east through tomorrow while continuing to weaken.
Satellite observations confirm the forecast fetch of 35-55kt winds (shown right) at the peak intensity of the low, with this fetch producing long-period fore-runners that are expected to arrive overnight Friday. The bulk of the swell will be in the 16s range, filling in strongly later Saturday afternoon ahead of a peak overnight.
With fresh SE tending E/SE winds Saturday, it's worth crossing out the day for a surf as well, but Sunday should offer clean conditions across most spots (not the Torquay reefs) with a morning N/NE breeze.
The Surf Coast should see good but inconsistent 3ft waves, with 3-4ft sets at 13th Beach, while the Mornington Peninsula should offer inconsistent 6ft+ waves across the open beaches during the morning, with a dropping trend across all locations seen during the afternoon.
Conditions early Monday should be great with a stiff N'ly wind but there won't be much size leftover and a S/SW change will move through during the day.
Longer term, an amplification of the Long Wave Trough will intensify just south-west of WA over the weekend and then push slowly east towards us next week. What this will effectively do is steer polar fronts up directly behind it (to the west), initially up towards WA (pictured right) before steering them through the Bight as it moves east.
This will result in a series of W/SW groundswells with the initial pulses being small and inconsistent through Tuesday afternoon and Wednesday morning, but bigger and closer-range levels of W/SW swell should fill in Wednesday afternoon and persist into the end of the week.
Winds at this stage look average through Wednesday in the wake of a weak change Tuesday afternoon, but we should see more favourable E/NE winds Thursday and then N'ly winds Friday. Check back here on Friday for an update on this though.