Sydney Hunter Illawarra Forecast by Steve Shearer (issued Mon June 23rd)

Features of the Forecast (tl;dr)

• Small E/NE trade swells Tues into Wed
• Small  NE windswell into the mix Tues with freshening N-NW winds
• W’ly winds strengthen Wed with tiny surf- possible small late kick in new S swell
• S swells build through Thurs becoming sizey with winds shifting SW-S through the day
• Solid S swell Fri AM with offshore winds, winds tending S-S/SE and easing
• Nice blend of S-S/SE swells Sat with light winds
• Small leftovers Sun from the S with small E/NE swell in the mix
• Long range E swell fills in Mon, persists Tues, easing Wed- long waits for sets!
• Long period S swell fills in Mon, holds Tues before easing
• More S pulses likely later next week
• Small E swells in the mix later next week with light winds

Recap

Small fun waves over the weekend with a mix of SE and E swells offering up 2 occ. 3ft surf Sat under light winds, dropping down a notch into Sun into the 2ft range.  Even smaller this morning with size in the 1-2ft range and light morning land breezes expected to tend to mod N’lies through the day as a front/low approaches from the west. That will be the major synoptic feature for the week- read on for details. 

Small E'ly swells in the water this morning

This week (June 23-27)

High pressure is in the centre of the Tasman with a complex trough, front and low system approaching from south of the Bight. We’ll see pre-fontal N’lies freshen through the short term into tomorrow, tending NW and then hard W’ly on Wed. A retreating trade fetch gets supercharged by a developing trough and low in the South Pacific, reaching maximum intensity between Tongan and Tahitian longitudes. Despite the travel distance, we should see some quality long range E swell from this source, with some size from the south this week as the front and low traverse the Tasman.

In the short run well see fresh winds from the N tomorrow, tending N/NW then NW in the a’noon as the system approaches from the west. Proximate winds to the NSW coastline aren’t very well aligned but the fetch does join up with better angled NE-E/NE winds off the top of the high. That should see a N/NE windswell with E/NE-NE swells mixed in offering up 2ft surf, likely boosting a notch to 2-3ft in the a’noon. There should be some clean sidewinders on offer as winds shift more offshore through the a’noon. 

Winds shift hard W/NW then W on Wed as the frontal system sweeps across the SE of the continent with small E/NE swells to 2ft offering a rideable wave if you can get out of the hard offshore winds. A late kick in S swell is still possible across southern NSW from gales out of Bass Strait sending highly refracted S swell back to the coast but it’s unlikely to show much more than 2ft at S swell magnets. Thurs is a much better bet.

A steep rise is likely Thurs - mostly generated by gales sling-shotting up from adjacent to Tasmania into the Central Tasman. Expect undersized surf early with directional S swell in the 2-3ft range. The trend will be steadily up through the morning before a more solid increase in mid period S swell pushes wave heights into the 5-6ft range with bigger 6-8ft surf likely at more exposed S breaks. Early winds will be W tending W/SW, shifting mod/fresh SW then S’ly through the a’noon so you’ll likely have to run away from max size to find a cleaner wave.

Plenty of size still in the water Fri morning with mid period S swell in the 5-6ft range, still in the 6 occ. 8ft range at exposed S bommies and beaches on the Hunter. Winds will be on the wane as a large high moves over southern NSW with a morning W-W/SW breeze tending light/mod SW-S then clocking around S-S/SE as the high pressure ridge fills in. We’ll see some longer period S in the mix as well from a deeper fetch that passed through the lower extremities of the Tasman Wed into Thurs. This will likely be indistinguishable from the stronger signal but will add underlying energy to 3 occ. 4ft into the mix. 

This weekend (Jun 28-29)

Winds will be on the improve over the weekend as a large, slow moving high drifts over NSW. Still some S’ly bias expected Sat (W-W/SW early) tending to light S-S/SE breezes. 

We should see winds even lighter Sun with land breezes extending well into the late morning before tending to light/variable seabreezes. 

The Tasman Low sits off New Zealand through Fri so we should see a nice S/SE swell through Sat morning, in the 3-4ft range with a slow easing trend in the a’noon.

Small leftovers from the S-S/SE on Sun in the 2 occ. 3ft range with some small E/NE swell filtering down from the retreating trade fetch offering surf of similar size but very slow. 

Next week (Jun 30 onwards)

Strong, slow moving high pressure moves into the Tasman next week, with a weak ridge along temperate NSW, stronger in the sub-tropics. Ewe should see light winds at least for the first half of the week with morning offshores and weak a’noon breezes which will tend more NE as the week goes on. 

We’re looking at mostly long range swell sources during this period. 

E’ly swells from the South Pacific fetch look to build into the 3 occ. 4ft range Mon and extend into Tues before easing Wed with very long waits for sets.

From the south we’ll see some southerly groundswell from a slow moving polar low over the weekend (see below) with a following system supplying more long range, long period S’ly groundswell. We should see sets to 3-4ft Mon a’noon, persisting into Tues with more S’ly pulses likely during the week. 

High pressure looks to remain stubborn in the Tasman next week although models are divergent as to the timing of a next series of fronts with GFS suggesting mid/late next week while EC holds high pressure right through next week with small E’ly swell filtering off the top of the high into temperate regions and another round of tradeswell for the sub-tropics. 

We’ll see how it’s shaping up on Wed.

Seeya then.