Sydney Hunter Illawarra Surf Forecast by Steve Shearer (issued Mon 17th July)

Features of the Forecast (tl;dr)

• Small S swell pulse Mon, easing quickly into Tues
• Front/trough pushing into Tasman Wed brings a strong spike in S swell with fresh S’ly winds
• Strong leftovers Thurs AM with offer winds, easing through the day
• Small clean SSE swell Fri into Sat
• Fun pulse of E/SE swell Sun with tricky wind outlook
• Dynamic outlook for next week as low pressure forms in Tasman, likely building SE-E/SE swell and onshore winds Mon- check back Wed for revisions

Recap

Not a great deal to recap for the weekend- if you found a 2ft wave you did very well. Mostly surf in the 1-1.5ft range, slightly more energetic Sat with clean conditions. Today is seeing some fresh S swell energy making landfall, sets in the 2ft range with swell magnets up in the 3ft range. There’s some lump and bump around after overnight onshores with winds expected to tend NE through the day.

Fresh energy today but with lump and bump on it

This week (Jul 17-21)

We’ve got a mobile pattern this week with high pressure over NSW slipping out into the Tasman, before a trough and front push into the Tasman in advance of another high cell moving over Southern NSW into the Tasman. We’ll see quite a few wind changes this week as a result and modest upgrade in S swell energy as the trough and front develop a handy fetch in the Tasman. A few juicy developments now showing in the medium term as well. Read on for details.

In the short run and todays small pulse of S swell winds back quickly overnight to leave a few weak 1-2ft leftovers tomorrow at S facing beaches. Early NW-N winds will tend variable around a coastal trough line- most likely with a W’ly component before a front pushing through bring W-W/SW winds by close of play. 

Wednesday now looks dynamic as the trough/front, with a strong pressure gradient to a high moving across NSW push S’ly quarter gales into the Tasman (see below). Early SW winds will freshen to strong wind level, and tend strong S’ly through the day. We’ll see a rapid rise in S swell Wed, up from an early 3ft into the 4-5ft range at S facing beaches by lunch-time, bigger 5-6ft on the Hunter. Fresh S’lies will confine clean condition to more protected location which will be much smaller- but there should be enough energy for surfable options.

Conditions change rapidly again for Thurs as the fetch moves across the Tasman and high pressure moves over temperate NSW. That should see morning W-W/NW breezes tending to N-NNE winds in the a’noon. Plenty of S swell is still expected for the morning, in the 4ft range across most S facing beaches, bigger 4-5ft on the Hunter. An easing trend sets in by mid morning and size looks to roll off quickly in the a’noon. 

Small and clean for Fri morning. We should see some SSE swell in the 2ft range coming from the off-axis fetch near the South Island. Condition deteriorate through the a’noon under another wind change, this time from the S-SSE as a decaying front pushes across Southern NSW. This may generate some small local S’ly windswell, of no size or quality.

This weekend (July 22-23)

Back to light winds Sat morning as another high cell moves over the region. Light land breezes tending to a’noon NE seabeezes is the most likely outcome at this stage. We should see some small, but workable SSE-SE swell from the remnants of the fetch near the South Island Sat, in the 2ft range on the sets.

That gets boosted a notch Sun. The trough moves NE and forms a large area of low pressure N of the North Island late this week. We may see some quality groundswell form this source depending on how the fetch is located with respect to the swell shadow of the North Island. Initially though strong winds out of Cook Strait and the west coast of the North Island send a small pulse of E/SE swell which looks to arrive Sun, under current modelling. Expect clean 2 to occasional 3ft surf Sun with a very tricky wind outlook as another trough and front approach. We may see light NW winds early before onshore winds develop. We’ll finesse that wind outlook Wed.

Next week (July 24 onwards)

Definitely the most dynamic looking outlook we’ve seen this winter next week. Models are all over the place so we’ll sketch out the basic outline and refine details as we move through the week. Lingering troughiness in the Tasman now looks to seed low pressure next week, likely with two centres. Around these two centres, potentially one off the Far North Coast of NSW and one off the South/Central Coast we’ll see S-SE winds strengthen through early next week. 

Depending on where these low pressure centres are located we’re likely to see building swells from the SE-E/SE Mon, into Tues. Winds look to be onshore initially Mon, potentially tending lighter Tues as the low moves away.

We’ll peg in size in the 3-5ft range Mon, likely easing down from that peak Tues/Wed. Revisions on size and timing highly likely.

We also may see some longer range E swell from the low off the top of the North Island later next week, in the 3-4ft range.

It’s a dynamic outlook with lots of model variance so make sure you check back in Wed for the latest update.

Seeya then.