Sydney Hunter Illawarra Surf Forecast by Steve Shearer (issued Wed 8th March)

Forecast Summary (tl;dr)

• Complex low moves into Tasman this week weakening as it does so, pulse of small S swell ahead Fri
• Small S swell Sat, with potential for NE windswell in the PM
• S’ly change likely Sun with small leftovers from S and NE
• Tricky outlook next week as trough of low pressure sits in Tasman - likely onshore winds and building NE-E swells Mon/Tues
• S’ly groundswell pulse Mon/Tues
• More S swell ahead and possible action from the tropics- stay tuned for updates

Recap

Winds tending offshore as a complex slow moving low drifts under Tasmania have supplied groomed conditions with clean 3ft surf from the E/NE for most of yesterday. Today has seen a drop in size with mostly 2ft surf, clean under a synoptic offshore wind with periods of sea breezes this a’noon before winds tend W/SW later in the day or overnight.

E'ly energy yesterday has eased into today

This week (Mar8-10)

The complex low pressure gyre is slowly moving under Tasmania with the majority of any swell generating winds in the swell shadow of Tasmania. Hot air being dragged down from tropical Australia is now slowly being displaced by the cooler air from the Southern Ocean and driving a synoptic W’ly flow across temperate NSW with the sub-tropics still subject to hot, Spring-like N’lies.

In the short run we’ll see winds tend W/SW to SW tomorrow as the low starts to move E, a trough clears the area and a new high pressure ridge fills in, bringing S-SE winds through the a’noon. Not much surf on the cards as E’ly swell sources dry up and minor amounts of S swell fill in, lucky to reach 1-2ft at the most exposed S swell magnets. Tiny elsewhere.

Weak high pressure moves out over temperate NSW at a Spring-like latitude on Friday, bringing light winds in the morning and freshening NE breezes in the a’noon. Just a little more S swell is expected, barely reaching 2ft at S facing beaches and tiny elsewhere with traces of E quadrant swell keeping it from being dead flat. Bring a big board to the beach in the morning with low expectations. Through the later a’noon we may see some workable NE windswell whipped up, although Sat is a better bet.

This weekend (Mar 11-12)

High pressure moving rapidly NE in the Tasman o/night Friday should see strengthening NE winds off the coast and a peak in NE windswell in the 2-3ft range for Sat morning. NW to N’ly winds may tend W/NW or even variable as a trough approaches, with a late S’ly change on the cards. We should also see a small kick in better quality mid period S swell from a trailing fetch around the complex low with sets to 2-3ft at S swell magnets Sat a’noon.

The trough brings early SW-S winds Sun, more W’ly on the Hunter with a small mixed bag of mid period S and NE swell to 2-3ft. Conditions are expected to deteriorate as S-SE winds kick in but lighter and more variable winds around troughy areas can’t be ruled out so keep tabs on local winds Sun and check Fri’s notes for a final finesse.

Next week (Mar13 onwards)

Tricky little pattern now on the radar for early next week and it’s likely we’ll have to take model outputs with a grain of salt right now. Sketching out the basic pattern we’re looking at Sundays trough forming a broad trough of low pressure/closed low in the Central/Northern Tasman proximate to the NSW Coast (see below). A NE infeed into this system looks to maintain or increase NE swell under once likely scenario.

Also in the mix Mon will be some longer period  swell from a last passing frontal progression in the lower Tasman (see below), with sets likely to fill into the 3ft range at S facing beaches.

Depending on the position of the broad low we may see winds tend SSE-E Mon and more E’ly Tues, with building swells likely from the NE to SE depending on where the low ends up. We’ll pencil in building surf to 3-4ft Tues with onshore winds.

Another trough line approaching the coast Wed may see winds shift W’ly which offers up good potential for rapidly improving conditions mid-week.

Further ahead and the schizoid pattern continues as a strong front and low approach from the Southern Ocean and a tropical depression drifts south into the South Pacific slot. Both of those may be useful swell generating sources by next weekend, but with so much instability to get through in the short term it’s highly likely we’ll see substantial revision on Fri.

Check back then for the latest.