Sydney Hunter Illawarra Surf Forecast by Steve Shearer (issued 3rd Mar)

Features of the Forecast (tl;dr)

• Mod/fresh SE winds through Tues/Wed, tending E/SE-E into Thurs/Fri
• Mix of building SE-E/SE swell and better quality E/NE swell from TC Alfred Tues/Wed
• Sizey mid period E swell continues Thurs/Fri though with nagging onshore winds
• Slow easing into the weekend with winds shifting E through NE
• NE winds into early next week before a trough brings a S’ly change Tues
• Spike in S-S/SE swell expected later Tues into Wed
• More E/NE swell later next week as tradewinds redevelop and remain persistent

Recap

Things went fairly close to script over the weekend with small E/NE swells Sat in the 2ft range, clean early under light winds before NE winds kicked up. Sun was bigger by a notch with NE windswell mixed in with E/NE swell, best early before a S’ly change. Mod/fresh S’lies today have whipped up some S’ly windswell, along with inconsistent surf from the E/NE, all sources totalling 2-3ft. We’ll see plenty of swell this week with a strong high in the Tasman and TC Alfred slow moving E of Brisbane but onshore winds will be a problem.

Still small this morning, much more swell ahead

This week (Mar3-7)

TC Alfred (984hPa) is currently about 465 km north-east of Brisbane and moving SE at 7kts. A new cradling high pressure system is moving east of Tasmania today and strengthening as it moves into the Tasman. Alfred is expected to move SE today, generating mod to large swells down the NSW coast (it’s already solid in the sub-tropics!). Alfred takes a westwards turn thorough Tues into Wed and there’s now model consensus we’ll see a coastal crossing in SEQLD or far NENSW Thurs or Fri. 

In the short run, the large high will form a broad fetch of SE-E/SE winds roughly contiguous with the southern flank of TC Alfred through tomorrow. That will start to generate plenty of local swell from that direction over the ensuing 24-48hrs, as well as plenty of onshore wind. Expect mod/fresh SE winds through Tues and Wed- likely even tending more E/SE through Wed a’noon. 

Swell direction will be broadly E, with some component of better quality  E/NE swell coming from the infeed into the cyclone. The dominant source will be the wind field in the Tasman, so keep expectations pegged reasonably low as far as quality goes.

We’ll see surf building through tomorrow from 3ft into the 4-5ft range. If you can get out of the SE wind, longer period E/NE swell should be offering better quality 3-4ft surf with the occ. bigger set. 

By Wed we should see wave heights from the same source elevate into the 5-6ft range with the occ. bigger set. Again, it’ll be necessary to find shelter from the SE tending E/SE wind.

Alfred should approach the sub-tropical coast on Thurs but the broad and strong supporting E’ly wind field will remain active as a swell source for the entire NSW coast, with only small attenuation in size as you head south of Sydney. Winds will continue to be a problem through as a nagging E/SE-E’ly continues to blow across the entire NSW Coast. Possibly a lighter, troughier area south of Batemans Bay may offer some relief but otherwise, looks like we’ll have to put with up the onshore wind. 

Similar for Fri. We may see a slight reduction in size depending on how fast Alfred approaches the coast but for the most part, we’ll see more solid mid period E’ly swell, likely holding in that 4-6ft range with E’ly winds. Lot’s of swell, but hard to find quality.

This weekend (Mar 8-9)

Under current modelling we’ll see Ex TC Alfred inland by Sat, with a reinforcing high moving into the Tasman, and the interplay between the two holding a E’ly flow across the sub-tropics, tending E to NE through temperate NSW. 

As pressure gradients ease back to a new plateau we’ll see surf size drop back to 3-5ft through Sat, and stabilise in the 3ft range Sun. 

Again, keep expectations pegged low as far as quality goes. There’ll still be plenty of swell energy to work with but the relentless onshore flow will be making most places very bumpy and lumpy. 

Next week (Mar 10 onwards)

We should see a day of NE winds next week with some workable E-E/NE swell coming from persistent winds in the Tasman in the wake of TC Alfred. 

By Tues a trough may deepen off the South Coast, bringing a S’ly change (see below). Models are still mixed on the fate of this trough, but it may deepen into quite a significant system, bringing a sharp increase in S swell o/night Tues and into Wed.  

We’ll pencil in size into the 4-5ft range for now and see how it looks through the week.

A strong high backs the trough, so as that system dissipates we’ll see more broad E’ly tradewinds in the South Pacific, Coral Sea and extending down into the Northern Tasman. That would suggest plenty of E’ly swell in the sub-tropics, with workable E/NE swells down into temperate NSW later next week. 

We’ll see how that looks on Wed, we’ve still got plenty to focus on with a tropical cyclone due east of Brisbane.

Seeya then.