Effective from: Tue 18 Jun '13, 06:45AM

Forecast prepared by Craig Brokensha
Next update Tue 18/6 1pm.

Previous day's summary:

The weekend started out slow ahead of a mix of strong new SW groundswells into Sunday. The swell pulsed strongly during the day and peaked overnight, before easing into yesterday. A weak change left unfavourable S'ly winds across the South West yesterday morning with S/SE winds around Perth, while Geraldton offered much cleaner conditions with a light offshore and peak in swell to 4-5ft.

This morning the swell is easing further under persistent S'ly winds in the South West, with lighter offshores further north.

Swell events within the forecast period:

Wave heights will continue to ease into tomorrow ahead of a new SW groundswell Thursday afternoon. This is being generated by a relatively weak polar front to our south-west, with the Margs region expected to build to 4-6ft, 2ft in Perth during the afternoon, with a late pulse to 2-3ft in Gero ahead of a peak early Friday to 3ft+. Winds on Thursday should tend variable during the afternoon after a morning E/NE'ly while Friday will see strengthening N/NE winds.

The outlook from the weekend onwards will become more than active as a node of the Long Wave Trough intensifies to our west and moves across us. This will direct a series of strong mid-latitude fronts towards us, generating pulses of W/SW groundswell from Saturday afternoon, well into the middle of next week.

The largest pulse at this stage is expected to fill in Tuesday, peaking at 10-12ft in the South West, 3-4ft+ in Perth and 6-8ft around Gero. Winds will unfortunately be poor and from the W/NW to W/SW during most of this period as each frontal system pushes through.

Long term forecast (6+ days):
The longer term outlook revovles around the sizes of the W/SW groundswell pulses due next week. Beyond this a large long-range SW groundswell is on the cards for the following weekend, but check back here on Thursday for the latest on this.