Significant low on the way
Victoria Forecast by Craig Brokensha (issued Monday 30th November)
Best Days: Exposed beaches tomorrow morning, protected spots for the keen into the afternoon, protected spots Wednesday and Thursday morning, Saturday morning on the beaches
The large swell seen into late last weekend tailed away into Saturday and a funky trough brought a strong onshore change just before dawn, but this quickly flipped back to the north creating cleanish, though funky conditions across the state's exposed beaches. The surf was easing from 2-3ft on the Surf Coast swell magnets and 3-5ft to the east before winds then swung onshore again late morning.
Yesterday was poor with strong onshore winds and smaller surf, while today conditions are improving on the beaches with a new building mid-period swell to 3-5ft on the exposed breaks, 2-3ft on the Surf Coast but not as clean.
This week and weekend (Dec 1 - 6)
Today's building mid-period energy was generated by a broad, though relatively weak frontal system spawning off a polar low that formed south-west of Western Australia last Friday.
This swell is due to hold tomorrow morning to 3ft on the Surf Coast and 4-6ft to the east, but a less consistent and stronger pulse of SW groundswell from the polar low is due to fill in through the day. We may see the odd bigger set at times with this pulse, and conditions look good for the beaches in the morning with a strong N/NE breeze.
Winds should ease and swing W'ly late morning/early afternoon before strengthening again from the W/SW-W ahead of an approaching front. This will favour protected spots for the keen.
This strengthening frontal system also originated from the polar low on the weekend, pushing north-east across Western Australia, drawing in heat and instability while dipping south-east and into our swell window tomorrow.
The combination of cold and hot, moisture laden air will result in the formation of a rapidly deepening and significant low pressure system, with it just falling short of reaching 'bombing' thresholds.
As this low deepens tomorrow we're expected to see a fetch of severe-gale W/SW-SW generated directly south-west of us, with core wind speeds reaching storm-force.
This will produce a large, consistent SW swell event with everything from long-period energy (from the strong core winds) to mid-period swell.
We should see the size building out of the W/SW initially Wednesday morning, with the largest pulse from the SW arriving into the afternoon, peaking late afternoon/evening.
Size wise, the Surf Coast should build from 4-5ft (magnets) to 6-8ft into the late afternoon, with 6-8ft surf to the east, building to 10ft+ into the late afternoon.
Winds will favour protected spots with a fresh to strong W/NW morning breeze on Wednesday, shifting SW late morning.
The swell will ease steadily as the low pushes east-southeast across Tassie on Wednesday, leaving easing 4-5ft+ waves on the Surf Coast early Thursday, 6-8ft on the Mornington Peninsula. Winds will be great for the Surf Coast and light W/NW ahead of S/SE sea breezes.
Come Friday an approaching front will bring fresh W/NW winds ahead of S/SW change, but smaller surf. Size wise the Surf Coast looks 2ft+, with 4ft sets to the east.
Moving into the weekend and winds should swing around to the NE on Saturday with small, easing mid-period swell from 2ft on the Surf Coast, 3ft to possibly 4ft to the east.
Into Sunday we're likely to see another strong low form more on top of us, though strongest once east of Tasmania. This will likely bring a low quality though possibly sizey localised windswell, but we'll have a closer look at this Wednesday and Friday.