Sydney, Hunter and Illawarra Surf Forecast Surf Forecast (issued Monday 24th February)

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thermalben started the topic in Monday, 24 Feb 2014 at 4:01pm

Sydney, Hunter and Illawarra Surf Forecast Surf Forecast by Ben Matson (issued Monday 24th February)

Best Days: Tues: fun south swell with light winds tending NE. Wed: smaller but still fun at south swell magnets before the NE wind.

Recap:  Plenty of southerly swell over the weekend but light to moderate onshores for much of Saturday turned fresh and gusty Sunday morning (before easing into the afternoon). Wave heights peaked in the 3-4ft range at exposed beaches but on the whole it wasn’t really memorable.

A new round of southerly groundswell started building across the coast this morning, and conditions were excellent with light offshore winds. However the swell is displaying a little less strength than was expected, and it’s very inconsistent with lots of waiting around between waves. Surf size has mainly been in the 3-4ft range although we have had some reports from one particularly exposed spot where 4-5ft+ sets were occasionally making their way through their lineup. 

Yet another pulse of even longer period south swell was detected at the Eden buoy early this morning (peak swell periods nudging 16 seconds) and this energy should be making landfall in Sydney very shortly. However we haven’t had any size confirmation along the South Coast yet so it’s difficult to know whether this swell is performing within model expectations. This morning’s size came in slightly under forecast expectations (mainly 3-4ft compared to 3-5ft), however I was hoping that the significant boost in swell period from 12 seconds to 16 seconds (due later today) would produce some 6ft bombs at the exposed reefs and offshore bombies (we’ll probably find out later this evening, well after these notes have been published).

This week (Feb 25-28)

The difficulty in Tuesday’s forecast is that the morning’s size estimate hinge on how well this afternoon’s pulse fares. On one hand, I’m inclined to pull back the figures because today’s surf was generally a touch smaller, and much weaker than expected. However, looking at the model data and satellite obs of the fetch in the southern Tasman (yesterday and today), it’s hard to consider a system of this strength and coverage will be worth only 3ft at south facing beaches (going by current model forecast output).

So, my gut feeling is to nudge up the numbers a little - especially in the afternoon when we’re looking at another pulse of long range southerly groundswell generated by a secondary front embedded within the main storm track. 

In any case winds will be freshening from the NE so you’ll have to hunt for some protection (aside from an early period of NW winds at dawn). So, expect very inconsistent 3ft to nearly 4ft waves at exposed south facing beaches (much smaller elsewhere) on Tuesday morning with perhaps a few bigger bombs after lunch as the new pulse moves through.

On Wednesday, we’ll finally be on the backside of this series of south swells and winds will remain fresh out of the NE (lighter and more more N’ly early). So south swell magnets will again be your best option with easing swells in the 2-3ft range. Expect a smaller combo of swells elsewhere around 1-2ft.

Thursday looks generally uninteresting. A shallow S/SE change will nose into the region, delivering fresh onshore winds but not really generating much in the way of useful swell. This change will however be linked in with a much stronger front passing south of Tasmania around the same time, which will kick up a long period south swell sometime around Friday (probably in the afternoon). 

This pattern looks a little weaker than similar systems of the last few days, and it’s slightly off-axis too so I’m going to pull back forecast expectations from this to 2-3ft at south facing beaches by the afternoon. At this stage we’re looking at a moderate ridge pushing across the southern/central NSW coast, driving onshore winds to most parts - so keep your expectations low (this will whip up a concurrent SE swell though, probably a shade smaller than the expectant S’ly swell).

This weekend (Mar 1-2)

Moderating onshores and residual swells for the weekend. With no major sources expected to fire up in the Tasman Sea, we’re looking at generally uninspiring waves this weekend. However winds should throttle back from Thurs/Fri so conditions should be manageable. 

Long term (Mar 1 onwards) 

Looking further ahead, and our long term prospects hinge around two regions in our peripheral swell windows. We’re looking at a steady cycle of fronts tracking south of the Tasman Sea, which should maintain at least small levels of south swell for exposed beaches next week.

Elsewhere - the tropical South Pacific is expected to show some muscle mid-late week as a tropical cyclone (probably) forms east of Vanuatu and tracks towards Fiji. Aside from the local destruction (which is worthy of an article in its own right, if current model data eventuates), swell prospects for southern NSW look dicey at this stage due to the lack of a strong supporting ridge to the south (however we should see a building trade swell in Northern NSW and the SE Qld region). I’ll keep an eye on it and update on Wednesday by which time the model data should have consolidated a little more.