Sydney Hunter Illawarra Surf Forecast by Steve Shearer (issued Fri 18th Mar)

Forecast Summary (tl;dr)

• Small surf Sat AM with S to SSE winds, short period S swell building in the a'noon and freshening winds
• Better winds Sun with increasing S swell
• S swell peaks Mon, with light AM winds 
• Light winds all day Tues with fun-sized swell, late pulse of SE swell possible
• SE pulse Wed with light NW winds early, late S'ly change
• Uncertain outlook later next week with trough and possible low forming, check Mon for latest update

Recap

The current swell cycle seems to be sending an endless amount of E’ly swell to the region. Yesterday saw surf mostly in the 3ft range with some locations seeing bigger 3-4ft waves and an a'noon pulse of 4-5ft surf. Winds were light and offshore early before tending E'ly.  Today has continued the theme with size down a half notch into the 3ft range, 2-3ft at some spots. It’s mostly E’ly swell with a small amount of SE swell in the mix. Light morning offshore breezes are now tending variable before a light/mod S/SE change. 

Clean, fun options to end the week with improving water quality

This weekend (Mar 19-20)

A decent strength cold front is passing into the Tasman Sea at the moment, and a trough in advance of the front is bringing a S’ly change to the region this a’noon. That front then forms a low, which becomes slow moving as it tracks NE towards the North Island. Swell is incoming from the front and the low, generating swell from the southern quadrant over the weekend and into next week.

Southerly winds will be the problem for Sat. A brief period of SW to SSW winds is possible in certain areas before winds really freshen, likely exceeding 20 knots by mid/late morning. That will confine surf to protected locations. Swell-wise, there’ll be some leftover SE swell in the water with 2-3ft sets, quickly overlapped by building short range S swell which will push up into the 3-4ft range by close of play. No great quality is expected so get in early before the wind really kicks in and keep expectations low.

Much more size is expected Sun as longer period swell trains from the S fill in through the a’noon. Expect it to still be a bit raggedy through the morning with a morning SW breeze on it. Winds will clock around to the S but at reduced speeds compared to Sat. Early size in the 3-4ft range at S face beaches will push up into the 4-5ft range during the day. Notable S facing coastlines will see the biggest surf and size will grade smaller into more sheltered locations. There should easily be enough size and period in the swell to find a rideable wave through Sun.

Next week (Mar21 onwards)

Plenty of strong S to S/SE swell in the water Mon. Winds are still going to be an issue, with the low tracking further north than models suggested on Wed. That will leave a lingering S’ly flow, likely SW through the morning, before tending light S to SE through the day. S to S/SE swell will peak through the morning in the 4-5ft range, biggest at S facing beaches, smaller into more sheltered spots. Expect an easing trend through the day, back down into the, back down into the 3-4ft range. Local land breezes should clean the surf up nicely for the early. 

Tuesday looks like a cracker of a day, with an elongated “bubble” high over most of coastal NSW from the temperate to sub-tropical regions leading to all day light winds. Surf will have dropped back from Mon with residual swell from the S/SE in the 3ft range at exposed breaks. 

The slow moving Tasman low does flare up again early Mon, with a chance of a rebuild in SE swell later Tues. Models are offering mixed messages on this- with some wave models suggesting the SE pulse won’t arrive until Wed. It’s certainly worth pencilling in a surf Wed a’noon with the light winds on offer. We’ll update Mon.

The bubble high drifts offshore Wed, bringing a N’ly flow. SE swell in the 3ft range and light NW winds through the morning offers up plenty of potential for good waves across the region. Another trough is expected to bring a late S’ly change to the region.

Into the end of next week and troughiness off the NSW Central Coast may form another low pressure system with a couple of wooly days of onshore wind likely Thurs/Fri. S’ly winds are likely to extend into next weekend, although that will depend on the position of any developing low pressure. It’s likely we’ll see substantial shifts in wind and swell potential from this system as next week progresses, so stay tuned.

At this stage S swell is on track for Sat/Sun next week.

We’re also tracking an increase in cold front activity below Tasmania later next week. Recent model runs have supressed that activity more to the south, with more zonal fetches but we’ll keep tabs on it over the weekend, looking for the seasonal shift which will see the Southern swell window become more active.

Till then, have a great weekend.