Sydney Hunter Illawarra Forecast by Steve Shearer (issued Fri August 1st)

Features of the Forecast (tl;dr)

• Dynamic weekend with complex low forming in Northern Tasman
• Moderate S/SE swells Sat increasing through the day with fresh SE winds
• Large E’ly swells through Sun with S/SE-S winds at fresh paces 
• Large E’ly swells through next week as massive low drifts towards the North Island, only slowly easing into Wed/Thurs
• Winds improving into next week with light land and S’ly winds Mon (may still be some bump around)
• Clean and large Tues/Wed with light winds
• Winds shifting S-S/SE Thurs, increasing Fri
• Potential for another low to form in Tasman next weekend -low confidence this far out- check back Mon for latest updates

Recap

S swells built into the 4ft range through yesterday with fresh S’ly quarter winds confining clean options to only a few breaks. Today has eased back a notch with morning SW breezes trying to clean up a lump, bump sea state. Still a few 3ft sets on offer at S exposed breaks for the keen.

Lumpy and bumpy but still a bit of size around this morning

This weekend (Aug 2-3)

A wild weekend is ahead as a complex low forms off the NENSW/SEQLD coast, backed by a strong high in the bight which moves SE of Tasmania over the weekend. By dawn Sat a low will be spinning up, likely just north of Coffs, with a secondary centre in the Coral Sea. By late morning into the afternoon, near gales to gales form off the Southern flank of the NSW low extending down through the MNC and Hunter, with strong E/SE-SE winds developing across Sydney to the Illawarra. 

So, raggedy with strong onshores for the day. Smaller than you expect for most of the day with windy 3ft surf early, trending upwards through the a’noon but unlikely to exceed 6ft of windy short range swell. 

O’night Sat into Sun the Coral Sea low will merge with the NSW low forming a deep and powerful low pressure system in the Northern Tasman. The merged low centre then rotates around the edge of the gyre, back SW then NW then NE, getting close to the North Coast and bringing S’ly gales to the North Coast and Gold Coast. 

E’ly severe gales to potential storm force winds develop about the southern flank of the new super low along with the S’ly gales on the western flank. Both those fetches will generate large and powerful surf through Sun. Across temperate NSW we should see surf roaring at first light, in the 6-8ft range, likely building further to 8ft+ wth bigger sets (10ft) through the day. Winds stay unfriendly with a mod/fresh SE flow that should tend more S/SE or even S’ly through the day, allowing a few select big wave spots to come online. 

Next week (Aug 4 onwards)

E’ly gales in a broad fetch remain into the new week with a massive high new New Zealand (1042hPa) acting as supporting cradle for the Tasman low which will be drifting eastwards to a slot north of the North Island. If anything that eastwards movement looks slower than modelled on Wed so large surf will persist at elevated levels for longer. 

Period draws out Mon so we may see even larger sets at big wave spots- up in the 10ft+ range or above. Lingering S’ly flow still looks to be an issue. We should see a morning SW flow, although with lump and bump still around before winds lay down to light S-SE breezes through the day. Surf stays large and pumping all day, maxing out most breaks. 

Only a small easing into Tues- 6-8 with 10ft sets still possibility and lots of juice in the sets. We should see a true land breeze through the morning before a light NE Seabreeze so if you want it big and clean, Tuesday now looks like the day. 

Only a very slight easing into Wed expected with 8ft sets still in the water, but slowing down and becoming less consistent (more 5-6ft). Clean again with light offshores tending to light S/SE breezes as a new high pressure ridge builds in weakly.

That ridge will see a strengthening S-SE flow through Thurs- still W-SW inshore early before tending S-S/SE at mod paces. Surf will still be elevated with 5-6ft sets, slowly backing down through the day. Don’t be surprised if there are still 8ft sneaker sets through the morning. It’s an incredibly active sea state.

Unfortunately Fri now looks to be marred by the strengthening high pressure ridge with winds freshening from the S/SE-SE and even tending E/SE through the day. That will see deteriorating surface conditions at all but the most sheltered spots with E’ly swells still hanging in the 4-5ft range.

We may even see another robust E’ly swell next weekend as a very strong high moves SE of Tasmania and another low forms off the NSW Coast. Models have been flip flopping on that possibility all week. We’ll flag it for now and see how it looks Mon. 

Until then, batten down the hatches and have a great weekend!