Sydney Hunter Illawarra Surf Forecast by Steve Shearer (issued Wed 22nd March)

Forecast Summary (tl;dr)

• Small SSE swell Thurs, small kick in size through the a’noon with fresh N’lies
• Mix of NE and E/NE swells Thurs PM
• S’ly change Fri with a brief window of offshore winds possible
• Onshore winds Sat/Sun with short range ESE-E/NE swells
• Traces of long period S swell Sun/ bigger Mon
• Flukey SSE groundswell a possibility later next week
• Dynamic outlook from mid next week, possible low in the Tasman but low confidence- check back Fri for updates
• More long period S swells likely from mid next week
• Tracking an active tropics but nothing major for temperate NSW at this stage- check back Wed for latest updates

Recap

Yesterday was an ugly mess wth all day onshore winds and a mix of S swells which topped out at 2-3ft, 3ft+ on the Hunter. Not appealing at all. Today has seen a big improvement in surface conditions with light offshore W-NW breezes and a small mixed bag of SSE and E swells in the 2-3ft range with bigger 3ft+ sets on the Hunter. 

Much cleaner today with fun options early

This week (Mar 22-24)

High pressure has now moved into the Tasman, weakening rapidly as it does so. In the south a small trough of low pressure off the Gippsland coast is aiding a N-NE flow through temperate NSW. In the Coral Sea a monsoon trough remains active with a persistent but unspectacular trade-wind flow maintaining a small E swell signal. The remnants of a low near the South Island are now dissipating after a final flare up yesterday. 

In the short run we’ll see N’ly winds freshen tomorrow as the trough moves off the Gippsland coast into the Tasman. Small amounts of SSE swell are on offer and we should see just a small bump in size through the a’noon from that last flare-up of the low today. Keep expectations modest- we’re looking at 2ft surf with some potential for 2-3ft surf in the a’noon. On top of that we should see some small NE windswell to 2ft in the a’noon. Nothing thrilling but surfable optins available.

A brief period of offshore W-NW winds are expected Fri before a S’ly change works it’s way north. There is model disagreement on the timing with EC suggesting the change before dawn and GFS allowing a window of an hr or two after sunrise. Small leftovers in the 2ft range will be on offer before the change hits and a modest lift in short range ESE swell later in the a’noon. Nothing amazing, just short period surf to 2ft.

This weekend (Mar 25-26)

 A stronger onshore flow is now expected this weekend as a trough deepens off the Mid North Coast on the leading edge of a new high. That will see increasing SSE-ESE winds Sat with dominant short range ESE swell to 3ft through the a’noon. In amongst that gurgle there’ll traces of longer period S swell, but with S facing beaches a mess it’ll be hard to utilise it.

More of the same Sun, with E’ly winds clocking around E/NE-NE through the day as the high moves into the Tasman. Expect mostly short period E-NE swell of poor quality to 2-3ft. A stronger pulse of long period S swell through the a’noon should supply some 3ft sets to S facing beaches, offering up potential under NE winds, if they clock around in time. 

Next week (Mar 27 onwards)

Monday now looks a better bet for long period S swell from an intensification and slight NE movement of a frontal progression and parent low early in the weekend. That should see S swell wrap in with periods in the 15 second range, and size in the 3ft range at S facing beaches with some outliers able to maximise long period swell in the 4ft range. Morning winds look good, straight offshore as another trough forms off the South Coast. Expect offshore winds until the trough brings a S’ly flow later in the day, or even early Tues. 

Much more dynamic looking outlook from early next week but with lots of model divergence we’ll take outputs with a grain of salt before committing to solid calls.

EC is suggesting a strong high pressure belt well south of Australia with a cell slipping SE of Tasmania by Tues next week and a trough forming a surface low in the Tasman. This low and high generate strong pressure gradients and a slow moving fetch aimed straight at NSW for days on end. Under that scenario we’re looking at days of solid surf, initially under an onshore flow likely Tues-Thurs at least.

GFS suggests a troughy pattern to persist in the Tasman with the high being shunted quickly Southwards, bringing small swells, mostly NE windswell with some long period S swell in the mix.

Both major models are persisting with the rare Ice shelf fetch of gales to severe gales early next week which increases odds for long period S-SSE swell later next week, likely showing Thurs/Fri.

We’re also tracking continuing E’ly swell potential from low pressure sitting on long tradewind fetches in the South Pacific. Most of this long range action looks to favour the sub-tropics at this stage but small amounts will filter down into temperate NSW and depending on local winds could be significant into next weekend. 

In short looks like we have lot to keep eyes on, most of it a bit flukey but offering up potential for some sneaky swells from far away sources.

Check back Fri for a last look before the weekend.