Sydney Hunter Illawarra Forecast by Steve Shearer (issued Mon July 1st)

Features of the Forecast (tl;dr)

• Better S'ly swell for Tuesday with early offshore winds (may be still bump across open exposures), onshores may kick in after lunch, a’noon kick in new S'ly swell
• Good S'ly swell Wed (tho' easing) however winds look dicey
• Average but surfable conditions for the rest of the week with plenty of chunky SE swell rebuilding from Wed PM
• Easing winds over the weekend with slowly easing SE swell, biggest Sat
• Long period S swell showing Sun
• Long period S swell pulses Mon/Tues next week with favourable N-NE winds
• Increase in NE windswell likely by Wed
• E/NE swell filtering down from sub-tropics at surfable levels from mid next week

Recap

Not much of note over the weekend with a minor S swell signal to 1-2ft Sat and tiny leftovers and marginal E swell to 0.5-1ft yesterday. Conditions were clean before a S’ly change kicked in after lunch. That S’ly change is associated with a low which has generated some new, raggedy S swell today in the 4-5ft range (smaller at protected spots). Most S exposures are already side shore or blown out by SW winds (Northern Beaches is cleanest) with some much smaller, cleaner surf tucked into more sheltered bays and behind headlands. We have an extended period of S’ly quarter winds ahead. Details below.

Wild and windy with plenty of size at S facing beaches

Clean, smaller and workable at more sheltered locations

This week (July 1-5)

The synoptic pattern looks unseasonal with a huge, slow moving high in the Bight, expected to be reinforced by another cell to create a blocking pattern below the continent and maintain a long lasting ridge up the Eastern Seaboard this week. Although the constant S-SE winds will be problematic there’ll be heaps of swell as low pressure remains in the Tasman, with a slingshot fetch expected as the low moves N during the week. A trough in the Coral Sea accentuates an unstable SE flow in the sub-tropics and adds a local source of SE-E/SE swell into the mix north of Coffs. The high will be dominant right through into next week, as it slowly drifts into the Tasman.

In the short run and through-out the working week we’ll see S’ly quarter winds. Mostly tending S/SE-SE.  Coastal pressure gradients should be light enough through tomorrow for a brief period of W-SW winds before winds clock around so you’ll need to get in early although true S exposures will still have plenty of lump and bump on them. Plenty of swell to work with as a mix of S tending S/SE swell and longer period true S swell makes landfall in the a’noon. Size in the 4-6ft range at S facing beaches but smaller at more protected options. There should be a few workable compromises through the morning. 

The northwards moving low and slingshot fetch will see winds freshen again on Wed, back up to mod paces at least from the S tending S/SE. A window of SW winds will be brief so get in quick for the cleanest conditions. A similar blend of mid period (dominant) and longer period S swells will ease a notch before building again in the a’noon from the S-S/SE. Again, size on the S facing beaches will be solid- up to 4-5ft again in the a’noon with bigger sets- but most surfable options will be smaller at more protected locations.

Similar winds for Thurs, early SW-S especially north of the Harbour, then tending mod S/SE to SE during the day. Wednesday’s increase in slightly better angled S/SE swell should hold through Thurs at roughly similar sizes across open exposures with just a tad more size into more sheltered locations with the better swell direction. Keep expectations pegged low though, there’ll still be a lot of wind and S-S/SE bump around.

Plenty of S/SE-SE swell hangs into Fri, with size holding in that 4-5ft range. We should start to see an easing in pressure gradients and local winds laying down in strength but it’s hard to see it cleaning up sufficiently for true exposed locations after a week of S-SE winds. Likely you’ll have to hit up protected and semi-sheltered spots again on Fri. 

This weekend (July 6-7)

Easing swells and easing winds over the weekend as the high cell approaches Tasmania and the pressure gradient relaxes across temperate NSW. We’ll still see S’ly quarter winds both days but local winds should be light enough for a morning land breeze sufficient to iron out some of the lump and bump at a greater range of locations.

Sat looks the biggest of the days with SE swells to 3-4 occ. 5ft set early, easing during the day.

Sun will continue the easing trend from the main source of SE swell with sets to 3ft , easing through the day. We will see some long period S groundswell show through Sun from a series of powerful fetches moving well to the south later this week and into the weekend. These fetches are better aimed at Pacific targets but the magnitude of the seas generated will see some long period sideband energy show across NSW starting Sun. Likely  some 3ft sets at S facing beaches and reefs through the a’noon. We may even see a more favourable E/NE-NE breeze develop in time for Sun a’noon. Check back Wed and we’ll finetune those winds.

Next week (July 8 onwards)

Winds should tend N’ly through early/mid next week as the high moves across the Tasman. We may see some NE windswell start to develop by mid next week with a stronger E/NE swell possible following that.

Otherwise, we’re looking at continuing S’ly groundswell pulses through this period. They’ll be flukey and overlapping so expect soft and slow periods and certain beaches may miss out altogether. Monday should see more 3ft sets with the occ. 4ft wave at S facing beaches.

That should continue into Tues before easing. Winds will be favourable for S facing reefs and beaches. 

With NE winds increasing mid week we may see some NE windswell develop. We’re also expecting, under current modelling, an increase in E-E/NE winds across the Southern Coral extending into Northern Tasman Seas. EC is even suggesting a broad area of low pressure forming in a trough line in the Coral Sea which would anchor this fetch. 

This will favour sub-tropical areas for an out of season E-E/NE swell but the fetch extends far enough south for E/NE swell to filter down into Central NSW by mid next week. Nothing sizey, in the 2-3ft range but offering a nice change from winter S swells.

Early days so let’s see how it looks on Wed.

Seeya then.