The headline act is a complex low system approaching Tasmania with an embedded front and linked to a long inland trough. A NE-E/NE infeed into this system is producing swell from that quarter today and as the low clears the swell shadow of Tasmania we’ll start to see swells from the S. Following systems next week look to generate stronger, longer period S’ly swells.
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A front and small low are now racing across the Tasman with a high over NSW moving into the Tasman and directing a freshening N’ly flow across most of the Eastern Seaboard and a developing tradewind flow. So far, so spring. A complex low, front and trough then approaches from the W, bringing a flush of W’ly winds and a S swell.
E’ly tradewinds look to develop through the Coral Sea later this week bringing workable E/NE swells.
No great change to the weekend f/cast. S swells will be the dominant force in the water through tomorrow, mostly mid period stuff whipped up by a proximate fetch of S-SSW winds generated by a front and trough of low pressure forming in the Tasman.
This trough then absorbs another trough of low pressure moving south from the South Pacific islands to form a large area of low pressure near New Zealand. Compared to Mondays notes the components of this complex pattern all look a little weaker and more mobile with reduced swell generating potential, but we will still see some useful pulses from the various incarnations of the broad pattern.
The trough is expected to move offshore and merge with a more tropical derived depression to form a large trough of low pressure in the Tasman over the weekend. This has been a feature of synoptic prognostic charts for a few weeks now, with forecasts generally tending to weaken and fall apart as the event unfolds.
We’ve still got the basic building blocks in place that we mentioned on Wed with the proviso that everything looks a little weaker and disjointed. High pressure moves NE of Tasmania and the troughs remain inland, although we may see a weaker trough area move off the North Coast of NSW early in the week. SE-E/SE tradewinds are established in the Central Coral Sea and will supply small tradewind swell for the first half of the week at least.
A cold front and long trough are bringing a S’ly change to the NSW coast, extending into the sub-tropics later today and overnight. There’s not a great deal of useful swell generating winds associated with the change so only modest short range S swells are expected to accompany it. The lingering troughy pattern gets much more dynamic over the weekend (and next week) as a powerful high approaches from the Bight.
The remnants of the weekends frontal systems have set up a fading off axis fetch near New Zealand with the current run of small S swells also on the way out. A weak mid week front will bring a wind change and a small flush of S swell but next week looks a bit more robust although with plenty of wind.
Sunday looks better, for size at least. The head of the fetch reaches almost to New Caledonia and this typically aids S swell penetration into SEQLD.