Sydney Hunter Illawarra Forecast by Steve Shearer (issued Wed April 17th)

Features of the Forecast (tl;dr)

• Easing swell combo Thurs with early light winds before S’ly winds kick in
• Offshore winds early Fri with small surf, S’lies later in the day with a small kick in short range S swell
• Ordinary short range S-S/SE swell Sat with S’ly winds
• Easing surf Sun with better winds
• Small surf to start next week with light winds
• Dynamic outlook later next week as trough or low drifts down from Coral Sea- early days with uncertain surf potential, check back Fri for updates

Recap

We saw small, clean surf through Tues morning with a slight increase in size in the a’noon, likely from both S and E swell sources making landfall. Really nice looking lines this morning with both S swell to 3ft and inconsistent, long range E swell sets to similar size (3ft+) under offshore winds which are expected to tend light SE, then light E/NE-NE through the a’noon. Some onshore S-SE flow around Sydney from a small trough hampered wave quality.

Clean lines on the NB's- S'ly winds spoiled the party elsewhere

This week (April 17 - 19)

No great change to the f/cast outlook this week. We’ve got a monster high (1033hPa) in the Bight and a weaker high cell in the Tasman, with some small troughs of low pressure lingering about the coastline. We’ll see a frontal intrusion later Thurs bring fresh SW/S before a new high pressure ridge quickly fills in behind the front.

In the short run we should see clean, or cleaner conditions tomorrow morning with offshore winds, tending W/SW then freshening from the SW-S as the front pushes through after lunch, although areas north of Sydney should see reasonably light winds until close of play. Expect very slow surf from the E with sets to 2 occ. 3ft when they come and some small sideband energy from the S offering energy to similar sizes at S facing beaches. 

Get in early Friday morning for offshore W/SW-SW winds and small leftovers to 2ft. The rest of the day looks ordinary with mod/fresh SW-S winds making a mess of S facing beaches and a modest increase in short range S swell to 2-3ft late in the day, not offering much in the way of quality or wrap into more protected locations. There’ll be a wave if you are keen for a go out but keep expectations very low as far as quality goes.

This weekend (April 20 - 21)

Not much to look forwards to this weekend as Ben mentioned on Mon. A weak area of low pressure drifts across the Tasman with as nondescript fetch of S-SE winds in the Tasman south of this area. We’ll see some short range S-S/SE swell to 3-4ft through Sat with winds remain mod from the S-S/SE so bumpy, sideshore surf at best is expected. Again, a wave for the keen, if you aren’t too fussy.

Improving winds Sun, as pressure gradient ease along the coast and we see a light SW breeze in the morning, tending to light SE-E/SE breezes in the a’noon. Short range S/SE swell comes down from Sat’s peak and we’ll be left with a workable but unremarkable 2-3ft surf for the morning, easing through the a’noon.

Next week (April 22 onwards)

Plenty of action in the tropics and subtropics next week but we’ll see a quiet opening to the week for temperate NSW, with some model divergence for later next week.

High pressure moves into the Tasman to start the week so we’ll see some light wind days to open the week. Monday for sure, Tues through the morning before NE winds kick in.

Not much swell both days. A small glancing blow of S swell Mon a’noon from a poorly positioned fronts below the continent should see some 2 occ. 3ft sets at S swell magnets Mon a’noon.

Easing through Tues. 

The rest of the week now looks increasingly dynamic and fluid, so expect revisions Fri.

The gist of it is a trough line in the Coral Sea, which may deepen into a low pressure system and drift towards the North Island (GFS scenario) or move towards the QLD coast as a coastal trough and intensify a NE infeed into the SEQLD, then NSW Coast possibly as early as Wed.

Big variations in outcomes there, with anything from rain, onshore winds and NE swell to quality E/SE swell for the sub-tropics, filtering down at reduced levels to temperate NSW later next week and into the weekend.

We may see a return S’ly flow from a low forming in the trough line off the Gippsland or Far South Coast next weekend. 

Lots of dynamic possibilities with very low confidence in outcomes this far out.

Check back Fri and we’ll see how it’s shaping up.