Shipstern Bluff Alert Guide

Tasmania, Australia · part of the Shipstern Bluff spot guide

Shipsterns is forecast-only — no buoy within range — so this is a model-swell alert, tuned as a high big-wave threshold. The height below is open-ocean; the slab jacks it into a face several times larger. This is an extreme-consequence, expert-only, rescue-supported wave.

The forecaster's checklist

1. 1.Want direction in the south-southwest slot — from about 180–225° is the money band within the wider acceptable arc.
2. 2.Period must be long — 14 seconds and up; the longer the period, the more the reef jacks and the more the step builds.
3. 3.Confirm the open-ocean height is over threshold: roughly a metre just to switch on, two metres of long period for the real slab, three metres for maxing and tow.
4. 4.Look for a light north-to-northwest offshore; anything with south in it is onshore.
5. 5.Treat this as an extreme-consequence, expert-only, rescue-supported wave — confirm the swell holds long enough to justify the boat ride or hike and that safety support is arranged.

Local winds & tide

Best wind: N–NW offshore — from 300° to 20° (WNW–NNE).

Tide-sensitive though not modelled; lower tide draws more water off the reef and makes the step more pronounced and heavier, while medium-to-higher tide is a touch more forgiving.

Dial it in