Sydney Hunter Illawarra Forecast by Steve Shearer (issued Mon July 8th)

Features of the Forecast (tl;dr)

• Long period S swell pulses easing Tues with favourable NW tending N-NE winds
• Small E/NE swell Tues with winds tending offshore
• Increase in E/NE swell likely by Wed
• E/NE swell filtering down from trough block at increasing levels from Thurs next week, peaking Sat/Sun with winds looking good
• Lots of sizey S swell expected next week as complex low forms in Tasman- check back Wed for latest revisions

Recap

Improving conditions over the weekend with Sat seeing the last day of S-SE flow and a mostly mid period SE swell to 3 occ. 4ft with improving conditions in the a'noon. By Sun morning offshore land breezes had set in with some 2-3ft surf from the SE and traces of long period S swell showing in the a’noon, with winds tending generally light E’ly in the a’noon. Conditions are mostly clean this morning under light land breezes with S swells showing around 3ft at open exposures and a small signal of E swell in the mix. A reinforcing pulse of S groundswell is not yet showing on the NSW buoy array but should show by close of play. Winds are expected to tend light/mod N-NE through the a’noon. Nothing amazing but definitely a welcome relief after the blustery, persistent SE winds of last week.

It finally cleaned up on Sun with a fun mixed bag

This week (July 8-12)

The monster high that was in the Bight last week is now in the Tasman and still dominating our local weather and surf conditions. An inland trough eventually clears the coast later Tues or Wed and the broad E’ly infeed into the trough transforms a typical but out of season tradewind fetch into a more broadscale “trough block” feature (see below) which will send swell to most of the Eastern Seaboard. By the weekend a front will capture the remnants of the trough and we’re looking at a solid return SW-S flow and resultant S’ly swells. Read on for details.

In the short run we’ll see N’ly quarter winds tomorrow, early NW, tending N’ly then backing around NW-W/NW as one arm of the trough and a small low near Tasmania approach. Small S groundswell should hold some 3ft sets at S facing beaches, easing in the a’noon with a small signal of E/NE swell off the top of the high showing in the 2ft range.

With the trough clearing the coast Wed we should see a straight offshore flow all day, veering between W and W/NW. With S swell dropped out of the mix we’ll be relying on a summer-style E/NE swell which should see some fun waves in the 2ft range with the occ. 3ft set.

Offshore winds for the rest of the week, so no need to hurry with both Thurs and Fri seeing mostly W tending W/NW winds. If we do see any seabreezes they will be late and light. Our E/NE swell will be slowly building. Still mostly 2 occ. 3ft Thurs but by Fri we should see a more consistent 3ft signal establish as the trough block starts to come to fruition. 

Definitely pencil in Thurs and especially Fri if you can. 

This weekend (July 13-14)

E-E/NE swells from the trough block peak Sat under current modelling and slowly ease Sun. Size should ramp up several notches into the 4-5ft range Sat, back into the 3-5ft range Sun and easing. So with plenty of swell from the favourable E/NE swell angle how are winds looking?

Basically favourable/workable but there will be some S’ly bias to them as a front brings the return flow around the stalled trough line. Sat morning should be mostly straight W’ly, tending W/SW then SW through the day. There is some model variance around a’noon winds with suggestions of a light SE flow developing or fresher SW-S/SW winds on the radar. 

SW winds look likely for Sun, tending S/SW-S in the a’noon. We’ll fine-tune those winds on Wed but with swells from the E/NE there should be plenty of clean corners on offer.

Next week (July 15 onwards)

There’s broad model agreement that the frontal passage over the weekend captures the stalled trough and coalesces into a broad, complex low in the Tasman next week. With the low in the Tasman establishing a broad fetch of strong winds to low end gales we’ll see a sizey S swell early next week. Current modelling suggests a strong start to the week with mid period S swell in the 4-5ft range, bigger at more direct S exposures and mod/fresh SW-S/SW winds. We’ll see some leftover E/NE swell in the mix through Mon in the 3ft range, easing right back Tues.

Plenty of action from the south next week with good odds we’ll see a stronger, longer period S swell later next week, either from a new, deeper fetch or a consolidation of the low near New Zealand. Low confidence specifics this far out so check back in Wed and we’ll start to sharpen the focus on next week. For now, we’ve got some tasty E/NE swell and offshore winds to look forwards too.

Check back Wed for the latest.