So when I met a delivery skipper in Albany who casually mentioned that he’d crossed The Bight 29 times, I was impressed. Despite The Bight's formidable reputation, he was surprisingly blasé about his track record, viewing it simply as a matter of picking the right weather window.
So what is the best time to cross The Bight?
The answer depends on which way you’re going and the time of year. It is critical to understand the weather systems in the southern hemisphere and, in particular, in southern Australia. Let’s dive into the key factors.
Prevailing Westerlies
Weather at middle latitudes, both north and south of the equator, travels in a generally west-to-east direction. This eastward movement applies to both high and low pressure systems, including cold fronts and troughs associated with the latter. The westerly movement is an indirect result of the Coriolis force, the force caused by Earth's rotation. Read the following explanation for more detail.The Australian High: A Seasonal Influence
A prominent weather feature in Australia is the Australian High, a large, semi-permanent area of high pressure that sits over Australia, and moves northward or southward with the seasons. The technical term is the Subtropical Ridge as it is long and relatively narrow, reminiscent of a ridge. For example, the following Bureau of Meteorology (BoM) synoptic chart shows the Australian High over central Australia in mid-winter.Summer Patterns: Ideal for Westward Crossings
In summer (December to February), the Australian High strengthens and moves southward, extending its influence over a larger part of southern Australia. This brings stable and dry conditions, with less chance of low-pressure systems and cold fronts reaching the south.In the Southern Hemisphere, air circulates anti-clockwise around highs. Therefore, a high located south of Australia will produce southerly/southeasterly winds as it approaches followed by easterly winds. This is desirable for a westward crossing.
For example, here is a late spring synoptic map from the BoM with a High that is located well south of The Bight.
The corresponding winds, forecast by PredictWind, are perfect for sailing west.
Winter and Shoulder Season Patterns: Navigating Lows for Eastward Crossings
In winter (June to August), the Australian High weakens and moves northward. This opens the door for low-pressure systems and cold fronts (i.e., the boundaries between warm and cool air) to travel eastward across southern Australia. In the Southern Hemisphere, air circulates clockwise around low-pressure systems, a pattern that can be remembered with the mnemonic 'cyclonic clockwise’, recalling that cyclones are extreme low-pressure systems.For example, here’s another BoM forecast for a cold front approaching The Bight in autumn.
Here’s another BoM synoptic chart, a couple of weeks later, showing a cold front that has already moved across The Bight.
This is the actual front that we used to sail from west to east in April 2025. We took advantage of winds backing to the south, i.e., changing from westerly to southerly, which propelled us east.
In our case, it was a fast-moving front and a few days later we were confronted with the following light conditions, necessitating that we motor part of the way. We anticipated this and deemed that lights winds were preferable to headwinds.
In our case, it was a fast-moving front and a few days later we were confronted with the following light conditions, necessitating that we motor part of the way. We anticipated this and deemed that lights winds were preferable to headwinds.
Finally, here is a mid-winter Low and its associated cold front moving across The Bight. Notice how far north the High is over eastern Australia and its elongated shape.

PredictWind forecasts strong trailing southerlies and southwesterlies for this Low.
Sea State
The final consideration is sea state. Winter brings huge seas that are best avoided, even if the winds are manageable. For example, PredictWind forecasts 9m seas to be associated with the above Low. As a rule, even if winds look favourable, it always pays to check wave and current forecasts.Conclusion
In summary, the best time for crossing The Bight from east to west is summer (December to February), when highs are located well south.The best time for crossing from west to east is more nuanced. In general, any time you can harness a low-pressure system is good. In practice, you won’t want to do so in the middle of the winter, which brings cold weather, strong winds, and big seas. The preferred times are therefore late spring (October to November) or early autumn (March to mid-April).
By understanding these different weather patterns, you can harness the right conditions to cross The Bight. I advise anyone planning a crossing to start studying the weather patterns several weeks in advance.
OVER.
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