Effective from: Wed 23 May '12, 01:30PM

Forecast prepared by Craig Brokensha
Next update Fri 25/5 1pm.

Previous day's summary:

Wave heights have slowly climbed over the last couple of days with the arrival of a couple of strong W/SW groundswells. This first increased from 3ft+ west of Melbourne and 6-8ft to the east yesterday morning to a larger size into the afternoon as fresh N/NW winds persisted all day. A bigger increase has been seen today to 4-5ft on the Surf Coast and 8ft+ on the Mornington Peninsula with stronger N/NW winds favouring the protected reefs on both coasts. A peak in size is expected this afternoon with winds shifting more NW but holding into the evening.

Swell events within the forecast period:

1) Easing W/SW groundswell tomorrow
Today's peak in size should be followed by an easing trend from 3-5ft on the Surf Coast tomorrow and 6-8ft on the Mornington Peninsula but a S/SE change will move in before dawn creating deteriorating conditions across both coasts. Friday will see winds becoming stronger from the SE before swinging more S'ly during the day, creating terrible conditions as the swell eases further.

2) Medium to large sized S/SW windswell building Saturday, easing Sunday with a medium sized S/SW groundswell for Sunday
A deepening low pressure system to our north will move east on Friday and Saturday resulting in an infeed of SE winds on its southern flank to swing S/SW during the same period. As we fall under the south-western flank of the low these S/SW winds will strengthen, kicking up a solid windswell for Saturday to 4-6ft on the Surf Coast during the afternoon and 6ft+ on the Mornington Peninsula. The windswell should back off through Sunday as the low moves further east and winds relax with a drop in size from 3-5ft and 6ft+ respectively.

As the windswell eases though a strong S/SW groundswell should fill in, produced by a vigorous polar frontal progression during Thursday and Friday morning. Winds will be in the severe-gale to sub-storm-force range producing a 3-5ft swell for the Surf Coast and a 6-8ft swell for the Mornington Peninsula. Unfortunately winds over the weekend will remain average besides a small window of early W'lys around Torquay on Saturday, with Sunday being onshore everywhere with a moderate to fresh SW'er. The swell should hold a similar size into Monday due to a secondary polar frontal progression producing a reinforcing S/SW groundswell and winds will also relax and probably tend W'ly early again around Torquay. Check back here on Friday though for confirmation of this.

Long term forecast (6+ days):
We're likely to see a continuation of small to medium sized S/SW groundswells through next week as winds swing back to a W/NW-SW pattern favouring the Surf Coast. Check back here on Friday though for an update on this and any other swells due later next week.