Sydney Hunter Illawarra Forecast by Steve Shearer (issued Fri April 12th)

Features of the Forecast (tl;dr)

• Pumping mix of SE-E swells from Tasman low Sat
• Renewal in SE swell Sun AM
• Light winds all weekend, offshore mornings tending SE Sat PM, more N-NE Sun PM
• S’ly groundswell pulses Sat, and Sun PM
• S’ly groundswell into Mon, easing during the day with light winds
• More light winds through Tues/Wed with offshore mornings and light SE breezes in the a’noon
• More S swell Tues/Wed
• Long range inconsistent E swell in the mix Tues PM-Thurs
• Possible dynamic situation next weekend with building E/NE swell from infeed into coastal trough
• Active tropics may see some E swell in the long run
• Dynamic Autumn pattern, check back Mon for latest updates

Recap

Plenty of size since Wed with size to 6ft yesterday from the S/SE and long range S groundswell in the mix from the a’noon. Swell direction has tended more favourably SE-E/SE, with some E/NE swell trains in the mix today and with the extra E in the angle, as well as long period S,  there’s a more even distribution of size in the 5-6ft range with a morning offshore breeze. In short, it’s pretty much pumping across a wide range of spots this morning. We’ll see a slight easing in wave heights through the day but with winds easing there should be plenty of good to potentially great surf on offer. 

Pumping this morning with enough size/period to make Bommies cap

This weekend (Apr 13-14)

We’ve still got an intense Tasman low in the picture sending plenty of swell our way, located now off the west coast of the South Island, with a large slow moving high SW of WA and powerful fronts under the SE of the continent. As pressure gradients ease in the Tasman Sea we’ll see light winds establish across the region with a mix of slowly easing SE-E swells and long period S pulses.
No great change to the weekend f/cast. Still solid and pumping for Sat morning with offshore winds. SE-E/SE and E swell should hold 4-5ft surf with the occ. bigger 6ft set and a mix of mid and long period S swells should be reinforced around midday with sets up to 4-5ft at S facing beaches. Variable winds through the a’noon that look to have a S’ly bias from the Illawarra south if you are planning on travel. 

Morning offshores for Sun with winds tending NW-N then light NE in the a’noon across the region. 

A renewal in SE swell to 4-5ft (occ. bigger set) Sun morning from a last intensification of the Tasman low near the South Island with another pulse of long period S boosting wave heights back to 3-5ft at S facing beaches and some outliers possible at direct S facing reefs.

Next week (Apr 15 onwards)

Offshore winds into Mon morning with Sundays pulse still lingering and offering 3ft surf at S exposed breaks with some bigger sets at S swell magnets and direct S facing reefs.

Pressure gradients now look weak through Tues and Wed, although we’ll see a weak SE flow develop Tues and possibly extending into Wed. We’ll see how those winds look on Mon as a weak troughy area off the coast may change the flow depending on it’s evolution.

More S groundswell expected next week, with a renewal in S swell Tues a’noon from a deep low passing under Tas later Sun into Mon (see below). We should see size back up into the 3-4ft range with occ. 5ft sets at S exposed breaks later Tues, holding into Wed. 

A sub-tropical low fires up a distant E’ly fetch this week in Tongan longitudes and despite the long travel distances, swell periods will be high enough to ensure some very inconsistent 2 occ. 3ft sets showing later Tues and holding through Wed into Thurs. 

Further ahead and the synoptic  pattern still looks dynamic. A small TC currently formed in the Coral Sea (TC Paul) won’t be a swell source, but remnants from this system may anchor an E’ly fetch in the Coral Sea. Closer to home, a trough forming along the coast may see another E/NE-NE infeed ( a variation of a black nor-easter pattern) later next week. Under current modelling we may see onshore winds and increasing E’ly-E/NE’ly swells later next week.  A tropical low may form in the Vanuatu/Fiji corridor during this period, with uncertain surf potential.

It’s basically a full spectrum Autumn pattern with lots of swell sources to keep an eye on.

Check back Mon and we’ll see how it’s shaping up. 

For now, enjoy the weekend of waves!