Dynamic week ahead as trough of low pressure forms in Tasman, with some tasty prospects next week
Sydney Hunter Illawarra Surf Forecast by Steve Shearer (issued Mon Sep 9th)
Features of the Forecast (tl;dr)
- Small S swell Tues with SW winds early tending variable and seabreeze in the a’noon
- Easing swells Wed
- Spike in new S swell Thurs as trough of low pressure forms offshore , windy from the S/SW-S/SE
- Potentially still sizey but easing S swells Fri with S/SE winds easing during the day
- Light winds Sat with a possible increase in new S swell in the PM
- S swells Sun with easing winds
- Mix of S swells likely early next week- potentially some good long period S'ly groundswell Tues
- Potential for quality E/NE-NE swells mid next week as winds feed into trough- definitely check back in Wed for latest updates
Recap
A small short range S-SE swell offered some occ. 2ft sets Sat, a little over f/cast expectations with clean morning conditions and a’noon SE breezes. Similar size for Sun with some 2ft sets from the S-S/SE and light winds, tending W’ly. Today has seen those small swells drop out of the mix with tiny surf in the 1ft range (the odd 1.5ft set on the Hunter) and light offshore breezes. We’ll see some sizier S swells show up by the end of the week, albeit with plenty of wind. Read on for details.
Small and grovelly Sun
This week (Sep 9-13)
We have a pair of weak highs in the Tasman and over Australia with a trough moving north through the sub-tropics and a zonal front pushing across the Tasman. Thats a typical spring pattern. A much stronger high is approaching from the Indian Ocean and expected to push into the Bight mid-week with a trough and low forming in the Tasman on Thursday. This much more energetic pattern will generate some size S swells for the end of the week with a following frontal system also looking juicy. Longer term we may see some action from the E-E/NE as winds from the strong high feed into an inland trough. Altogether a much more active outlook.
In the short run a weak, troughy area off the Central NSW Coast looks to direct morning SW breezes which should clock around light S-SE before washing out to variable then light NE seabreezes. We should see some small, but workable S swell with 2ft sets early, boosting a little during the day to 2-3ft (bigger sets likely on the Hunter) with workable winds at S magnets, especially in the a’noon.
That little pulse then winds back Wed with a little grovel in the 1-1.5ft range on tap with light NW breezes tending N/NE in the a’noon. A trough/front will see winds shift W-SW south of Jervis Bay in the a’noon but any wind change isn’t likely until after dark through the Illawarra-Syd region. Not much swell to work with anyhow.
Thursday looks like a dynamic day. A trough deepens and inflames a strong S’ly flow along the NSW coast, extending into the Tasman. Were should see mod/fresh S/SW winds early tend S’ly and S/SE’ly during the day. We’ll note EC has a significantly stronger and more explosive system which would generate a steeper and sizier increase in short range S swell during Thurs, likely pushing up up into the 4-6ft range. GFS has a more modest system and increase, with short range S swell up into the 3-4 ft range. We’ll finetune size and timing on Wed as we get closer to the event. Either way it’ll be windy and blown out on open stretches so you’ll need to seek some wind protection.
We should see easing swells Fri, with revisions likely Wed on size and timing. The broad scale pattern is for the trough of low pressure to rotate away and move NE with a weakening pressure gradient on the coast. That would suggest a mod S/SE flow easing tending to light seabreezes in the a’noon. We’ll pencil in 3-4ft of easing S-S/SE swell and revise on Wed. An upgrade could easily be on the cards.
This weekend (Sep14-15)
Low confidence in the weekend f/cast due to uncertainty over the strength of follow-up fronts pushing into the Tasman. We should see light winds Sat morning with some fun waves from the S before the next front pushes through with S’ly winds. EC has a much stronger frontal intrusion than GFS, suggesting a Sat PM spike in new S swell.
That swell would then extend into Sun at sizey levels (4-5ft).
GFS has a much more subdued frontal system, with a weak S’ly change Sat and a small increase in S swell for Sun as winds shift SE-E/SE under a new high pressure ridge.
EC has been consistent run to run on their outlook even if their resolution does look more winter than spring. Stay tuned for updates Wed.
Next week (Sep16 onwards)
High pressure moves into the Tasman next week and looks to immediately migrate NE, with winds shifting from SE-E/SE on Mon to the E and E/NE through Tues. Low confidence on size but we should see a mix of S and SE swells to start the week.
Included in that mix is a potential long period S'ly groundswell for Tues off a polar low slow moving under the continent/Tasman Sea into the weekend.
The real interest comes mid-week with a potential inland trough moving towards the coast and anchoring a strong and broad NE infeed from the strong high (see below). Under this scenario we’ll be looking at some real quality from the E/NE-NE mid week. Still too far off to have any real confidence in size or timing but if does play out as modelled by GFS we could be looking at quality surf with winds shifting W’ly at the peak of the swell. Might be prudent to pencil in Wed and potentially Thurs next week and check back in Wed for a clearer picture of how things are shaping up.
Seeya then.
Comments
Check the bait ball at Avoca, that's surf I would pass on if I saw that.
How's the bait ball forming a circle around the surfer!
https://i.imgur.com/l1ZLpM7.mp4
Saw one of the biggest, densest bait balls I have ever seen, probably 30 metre diameter circle, up northern stretches of central coast this morning. Bigger fish having a go but the resident dolphin pods hadn’t got there yet.