Lots of swell sources on the boil
Sydney, Hunter and Illawarra Surf Forecast by Ben Matson (issued Friday 24th January)
Best Days: Most days should have fun peaky waves.
Recap: NE windswells built through Thursday, reaching much higher than the 3ft+ forecast, with some locations pushing 4-5ft+ at times late in the day. Conditions were generally average with moderate to fresh N’ly winds though there was a brief period of NW winds in the afternoon. Size has eased slightly today from 3-5ft, and there’s also some long lines of E/NE groundswell in the mix, from ex-TC Toni. A moderate S’ly change arrived in Sydney a few hours before dawn; light variable winds have padded out most beaches throughout the day so conditions have been good.
This weekend (Jan 25 - 26)
To be honest, I’m a little perplexed at the size across some Sydney beaches today. The forecast models suggested a healthy fetch, so 4ft sets were always possible (hence the 3ft+ forecast), but observed wave heights seem to be disproportionately high, and the limited ASCAT passes didn’t reveal much about the source of this energy either.
What’s important today is that we ascertain which swell train is contributing the most size to the mix. Reason being is that the NE windswell is drying up quickly (and will be much smaller by Saturday) but if the major component is the unusual, long range E/NE swell diffracting around New Zealand’s North Island from poorly-located ex-TC Toni, then that swell is likely to persist a little longer so we need to recalibrate our expectations.
Reports on the ground suggest the NE windswell was initially the most dominant today, and that the underlying E/NE groundswell was a smaller component - but it seems to have switched a little this afternoon as the swell trend has eased back. So with this in mind I’m going to marginally upgrade wave heights from this quadrant into the 2-3ft range for Saturday. However there will be extremely long breaks for the bigger sets (out of the E/NE). These swells will show best Saturday and then become a little smaller into Sunday.
Also in the mix on Saturday will be a short range E/SE swell, from the bottom of the stalled trough lying across the coast. Set waves should manage 2ft early from this source, building to 2-3ft throughout the day, and mixed in with the E/NE and fading NE swells should produce fun waves at open beaches. This swell will then also slowly fade through Sunday.
Surface conditions look a little tricky on Saturday, though we should come out on top across most coasts. The stalled trough will drive moderate to maybe fresh E’ly winds into some coastal regions overnight, and the overall flow will swing to the NE during Saturday but it will also weaken. We should see pockets of light variable winds across the region too, possibly in the morning but more likely into the afternoon.
Sunday looks better with light variable winds everywhere in the morning, ahead of freshening NE winds into the afternoon. A redeveloping N’ly flow off the Lower Mid North Coast from Saturday evening through much of Sunday will counter the otherwise easing swell trends from the E/SE and E/NE, so expect peaky 2ft waves at open beaches in the morning to build to 3ft by the afternoon at NE facing locations (locations south from the Illawarra may see a lag on this increasing trend though, due to the northern position of the fetch).
So, there’ll be plenty of waves this weekend, you’ve just gotta pick the eyes out of it.
Next week (Jan 27 onwards)
Next week still looks a little ordinary, but there’ll be plenty of options if you're keen.
Winds look to be generally OK, light and variable for much of the week under a persistent troughy pattern, though a southerly incursion (sorry, I’ve been using that word a bit lately) is likely late Tuesday on the South Coast, easing rapidly elsewhere from early Wednesday.
The first two days of the week will pick up peaky NE windswells in the 2-3ft range but only a minor S’ly swell is expected in the lee of the change (peaking early Wed). These sources will then ease from later Wednesdsy through Thursday and Friday.
Strong but poorly aligned fronts under the continent this weekend may generate small background swells for south swell magnets all week, but no major size is likely.
The other long term swell prospects are to our (distant) east north-east, and then north-east.
Over the weekend, a small tropical cyclone is expected to form in the vicinity of Samoa, before tracking south and then stalling for a few days (see below).
The very large travel distance and only modest supporting ridge to the south will limit swell growth potential (relative to Australia) but we should see some small sets appearing later next week in the 2ft to maybe 3ft range at exposed beaches, persisting through next weekend (expect enormously long breaks between waves). It's not a swell event to get particularly excited about.
Beyond this, aside from some interesting frontal progressions across the Tasmanian divide that should generate new S’ly swells later next weekend and into the first half of the following week, we’ve got some broadscale tropical developments worth monitoring that’ll probably start to flare up during the middle to latter part of that week (i.e. between Feb 5-8). This is expected to generate a sustained run of strong E/NE swell for Southern NSW, probably peaking over the following weekend (i.e. around Feb 8/9, give or take).
Let’s take a closer look at this development in Monday’s update, as I’ve got a gut feeling the models will slowly shunt it back a few days, and we’ll need to recalculate the arrival time. But, it’s a very promising sign for swell potential from this swell window, as there’s a good chance a swell-producing tropical cyclone will develop in this region (just south of New Caledonia/Fiji etc).
Have a great weekend!