Small weekend south swell; strong S'ly swell and rare NE swell for next week
Sydney, Hunter and Illawarra Surf Forecast by Ben Matson (issued Friday 5th May)
Best Days: Sat AM: small leftover S'ly swell. Mon/Tues: solid S'ly swell, early favourable winds. Wed/Thurs AM: flukey, rare but possibly worthwhile long period NE swell at a handful of locations. Will be hit and miss but winds will be good.
Recap: Thursday came in a little undercooked, with a mid range south swell not delivering much more than average quality 2ft+ sets. Today’s expected long range S’ly swell delivered some great waves though, performing slightly better than expected (and a LOT better than model guidance suggested in earlier in the week). South facing beaches have picked up solid 3ft+ sets at times, though a little inconsistent. Winds are light so it's clean.
This weekend (May 6 - 7)
Still no changes to the weekend forecast, from what has been discussed on Monday and Wednesday.
Today’s south swell will ease overnight and further into Saturday. Despite today's waves coming in marginally bigger than expected, I still think early Saturday morning could see occasional 2ft+ sets at south facing beaches (bigger in the Hunter), before easing during the day. It will however be much smaller at beaches with less southerly exposure. Light to moderate NW winds will keep conditions clean.
Smaller but similarly clean waves will then pad out much of Sunday. Model guidance has a minor pulse of S’ly swell in the mix but it’s slightly SE of S (169 degrees) so isn’t sourced from the developing low/front (the swell from this is not due until overnight anyway) and with peak period around 14-15 seconds, suggests a polar origin, south or south-east of the broader Tasman region.
I can’t recall anything noteworthy in our far swell windows over the last few days of data observations, and (truth be told) haven’t had the time this afternoon to hindcast every possible region it may have originated from - so gut feel leads me to believe there won’t be much surf around the traps on Sunday. But with the model guidance suggesting a 0.7m, it’s just big enough not to completely rule out either.
If I’m wrong, and there ends up being clean waves bigger than 1-2ft before 3pm on Sunday, I’ll punish myself to a morning of brutal hindcasting on Monday morning, to work out where it originated from. Otherwise, I’m comfortable in the notion that Sunday (probably) won’t deliver much in the way of quality surf for the Sydney basin.
Winds will veer from the W/SW to the SW then S throughout the day as a low develops east of Tasmania.
As discussed all week, we are expecting a strong S swell from one of my favourite swell windows over the following 24 hours - the waters east of Bass Strait - but I am skeptical that we’ll see much new energy before the sun goes down. South facing beaches may pick up some stray 2ft+ sets in the hour or two before dark, but this is a low percentage game for now (models have also downgraded the strength of this fetch, which will slow its arrival time).
Next week (May 8 onwards)
Our developing low to the south is still on track for some solid south swell early next week. However the particulars have swung around slightly since Wednesday's notes.
The developing low is now expected to undertake a more classic path east of Tasmania, developing S’ly gales within a thin fetch and spreading large southerly swells across the region, before the low tracks slowly eastwards. The resulting surf is now expected to peak a little earlier, with late Monday and early Tuesday looking at maximum surf size around 4-6ft across south facing beaches. We should see anywhere between 6ft and maybe 8ft across reliable south swell magnets across the Hunter, but as per usual locations with less southerly exposure will be much smaller in size.
Winds are looking to remain moderate SW on Monday tending S’ly on Tuesday, but the pressure gradient should be light enough to allow for a reasonable spread of early W/SW winds across many locations early in the morning.
This Tasman Low looks like it’ll meander about the southern Tasman Sea for a few days as it weakens so expect slowly easing S/SE swells from Wednesday through until the weekend.
Looking further afield and TC Donna is pushing just north of Vanuatu at the moment. It’s seen some small, but significant changes within the model guidance over the last three days, as per the chart below - this is a snapshot of every model run since Wednesday night, showing what it’s predicted for Sunday morning each time. By looking at the model's evolution this way, we can more accurately assess the broader model trends.
In this case, we’ve shifted from a scenario on Wednesday where TC Donna was expected to remain completely outside of our swell window due to the swell shadow afforded by New Caledonia (Wednesday night's model run), to a situation where it's now a possible swell generator for many parts of the East Coast (Friday morning's run).
The models have essentially shifted Sunday morning’s position further to the NW, which is now well and truly inside the swell window for SE Qld (as such, they are now looking at the possibility of a solid cyclone swell here on Tuesday).
This swell window is pretty acute for Southern NSW, but if we do indeed see some long period NE swell push down the coast, it’s quite plausible that a handful of well placed NE swell magnets could pick up some useful NE swell through Wednesday afternoon and possibly early Thursday. As you can see from the model guidance to the right (this data point is for the Northern Beaches), we’re seeing leading edge periods of 16 seconds late Tuesday, reaching a peak in size late Wednesday upon to half a metre at 13.6 seconds. I think the model trend is good, but the swell heights and size conversion isn’t right - by my estimates we could see occasional 3ft+ sets at some locations.
But because of the flukey swell source and many obstacles between it and our region, I would only expect a small percentage of NE facing beaches to pick up anything useful.
Anyway, let’s check back on Monday to see how the weekend’s satellite observations stacked up and whether there are several quality inbound swells for next week.
Have a great weekend!
Comments
Why is the bass straight angle a favourite? They tend to be so acutely S in direction that quality tends to be low (at least for the first 12 hours or so).
It's a favourite from a personal forecasting perspective. This region was always one of those "where did that swell come from" sources, and it often produces very nice waves (mainly around the Hunter) considering the fetch is often aimed 130-150 dgerees away from the coast.
Got ya and it is an interesting phenomenon re the spread and refraction back. The northern beaches however isn't really much of a fan of that source.
Yep I agree. But the Cronulla region and the Hunter coast loves this swell direction :)
Pretty good jump in size about 1030am on the south coast, Ben. Sets in the head high to slightly overhead range then dropped off a bit as the tide bottomed out. Earlier in the morning it was waist to chest high.
Interesting.. thanks for the feedback. Was tiny in Sydney around 4pm when I checked the cams. Buoy data did have a spike an hour before dark though.. may have been the same pulse (exiting eastern Bass Strait).
It was a bit of a flash in the pan. All gone by the time I had another session late in the arvo but 1030am until about midday was much bigger than the rest of the day.