Eastern Tasmanian Surf Forecast by Steve Shearer (issued Mon Oct 24th)

Features of the Forecast (tl;dr)

• Plenty of E swell building Mon, tending NE-SE through Tues/Wed as tropical low drifts towards Tasmania
• Winds tending offshore Thurs next week with easing swells
• Small surf Fri into the weekend
• Tracking possible small NE swell next Mon then stronger S swells from mid next week

Recap

Plenty of swell energy and onshore winds to go with it. Sat saw strong swell from the NE in the 4-5ft range with N’ly winds tending SW-S after a change. Sun saw a mix of NE and short range SE swell in the 3-5ft range with strong S’lies. Today has seen fresh E’ly winds with strong 4-6ft surf developing from the E to E/NE. Onshore winds will be a problem for a few days yet, with plenty more swell incoming.

This week and next week (Oct24-Nov4)

A sub-tropical low which threatened SEQLD and NENSW over the weekend after it formed off the Capricorn coast is now steaming southwards at a fair clip, sliding along a high pressure ridge from a large (1035 hPa) high under Tasmania and dragging a strong fetch with it into the East Tas swell window. The low is expected to merge with an inland low and horseshoe trough on the Gippsland Coast tomorrow forming a stalled low pressure gyre near Tasmania (see below) through to the end of the week. This will maintain an onshore flow across East Tas until Thurs.

In the short run and we’re looking at plenty of size and onshore wind through tomorrow as the low tracks south to be off the Gippsland Coast late Tues. Expect size in the 4-6ft range, mostly from the E/NE to E and winds from the E, tending more E/SE-SE through the day.

This onshore flow from the SE continues through Wed with size increasing into the 6-8ft range as a fetch of E-E/SE winds aims up straight at the East Coast. It won’t be pretty under onshore winds.

Winds should tend more NW to WSW depending on the position of the low which is expected to hover just south of the Island. Expect easing surf from the E to ESE as the fetch of winds on the bottom of the low dips a little lower and not aiming directly at East Tas. There’ll also be another pulse of NE swell from a fetch in the Tasman still feeding into the low, with sets to 4ft.

By Friday freshening NW winds are expected as a cold front joins the low and sweeps through Bass Strait. Expect easing swells with surf to 2-3ft, easing during the day.

Not much expected over the weekend as the low finally starts to move East. Sat looks tiny and Sun may see a small S swell as a front sweeps around the SW flank of the low but it looks like a flukey source and not worth much more than 23ft at S facing beaches. 

Into next week and a high in the Tasman next week and another approaching mid-latitude low and trough system fires up a N’ly flow through Mon with a proximate fetch likely to deliver some NE windswell through the late a’noon, provisionally in the 3ft range. Expect this surf to hold through Tues under current modelling before the and possibly a frontal system push into the Tasman later Tues or Wed.

This may be a more favourable set-up for S swell than we have seen so far this Spring. EC model suggests possible some mid-sized S swell from mid/late next week. GFS is a little less bullish. 

We’ll flag it for now, and see how it its shaping up on Wed. 

In the mean-time there’s a dynamic situation in the near term to focus on.

Seeya Wed.