Eyes to the South next week with a very uncertain wind outlook

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Steve Shearer (freeride76)

Sydney Hunter Illawarra Surf Forecast by Steve Shearer (issued Fri 24thMarch)

Forecast Summary (tl;dr)

  • S’ly change Fri with a window of offshore winds beforehand
  • Onshore winds Sat/Sun with short range ESE-E/NE swells
  • Traces of long period S swell Sun/ bigger Mon
  • Very uncertain wind outlook from Tues next week due troughs in the Tasman- check back Mon for revision
  • Flukey SSE groundswell Fri next week
  • Dynamic outlook from mid next week, possible low in the Tasman but low confidence- check back Mon for updates
  • More long period S swells Wed-Fri


Small fun waves yesterday in the 2ft range with a little kick in size through the a’noon into the 2-3ft range, 3ft+ on the Hunter. Light NW winds tended N’ly in the a’noon. This morning is seeing clean conditions and small 2ft leftovers from the E to SSE, offering up some fun peaks. Early offshore winds are expected to tend S’ly as a trough pushes through the region and stalls off the Mid North Coast. 

Small and clean this morning before the S'ly

This weekend (Mar 25-26)

Friday’s trough moves out into the Central/Northern Tasman as a SE/NW angled line but weaker than modelled previously. We’ll still see quite a fresh onshore flow through Sat, SE to ESE and strong enough to make a mess of most beaches apart from the very sheltered north facing coves. Not a great deal of surf to be enticed by either. A small blend of short period E swells to 2ft early with a modest rise in short range ESE swell in the a’noon which will add another foot on top. Low quality, onshore slop in short.

Sunday looks marginally better. We should see pockets of lighter winds, possible land breezes north of the Harbour for the early with short range ESE swell offering up some peaky 2-3ft surf.  Onshore winds will kick back in again through the morning, clocking around from E/SE through E/NE and more NE south of Sydney. We’re also still on track for some longer period S swell to fill in over the a’noon, with sets to 2-3ft at S facing beaches.

Next week (Mar 27 onwards)

Monday still looking 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. We’re still expecting to see S swell wrap in with periods in the 14-15 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 far  South Coast/Gippsland. We should see early W/NW winds tending NW with a period of variable winds before a possible late S’ly change depending on how the trough behaves.

Incredibly we’re still looking at tremendous model divergence for next week which makes for low confidence in forecasts, especially local winds.

EC is still firm on the trough moving out into the Tasman, deepening and interacting with a large high driving SE-ESE winds through the Tasman and generating moderate swells from that direction from Wed onwards. They suggest another inland trough exiting the coast near Gippsland Wed bringing NW winds before a S’ly change Thurs.

GFS has the trough retrograding back towards Tasmania with continuing NW to N’ly winds across temperate NSW with a troughy patten and S’ly change Fri.

Looks like we will be in for a bumpy ride for local winds next week but periods of offshore and NW breezes look highly likely until Fri. 

Swells look easier to call. Long period S swells will be the dominant swell trains next week as a complex low traverses the far southern Tasman Sea and become slow moving in New Zealand longitudes (see below). The fetches aren’t perfectly aligned so, as per most of these events, there’ll be a big spread of sizes even for S facing beaches and certain outliers especially deepwater adjacent reefs will show more size due to period focusing effects.

Mondays pulse looks to retract in size Tues with 2ft sets at S facing beaches and NW winds (we’ll fine-tune on Mon).

Wednesday should see a stronger S swell fill from a low passing through Sun/Mon, with the head of the fetch reaching close to Tasmanian latitudes. Expect 3-4ft sets at S facing beaches with uncertain winds. Possibly favourable for a wide swathe of S facing beaches under GFS scenario. Keep in mind this could all be overlayed by moderate SE-ESE swell from the Tasman under the EC scenario!

The end of next week looks even more unpredictable as far as winds go. Thurs could be fresh S’lies or light NW’ers. Looks like Wed’s pulse will climb down rapidly.

Friday looks interesting with the low stalling near the South Island and gales off the eastern edge of the ice shelf expected to see SSE groundswell slip up the Tasman Sea. Local winds permitting we should see some inconsistent 3ft sets along with more local S swell if we see a low develop SE of Tas Thurs.

That low looks set to build bigger S swells into next weekend.

Expect major revisions on local winds when we come back Mon, but good windows do look highly likely and we’ve got high confidence that the next week will be dominated by S swell pulses.

Check back then and have a great weekend!


dannyz's picture
dannyz's picture
dannyz Friday, 24 Mar 2023 at 10:12pm