When sailing south in winter on the southern coast, we were give a piece of advice that has served us well. We were told to "Look for a high in The Bight of 1030 hPa centre pressure and then go as far as you can before the next front arrives". A good piece of advice with two important elements. Firstly, the centre pressure must be 1030 hPa or greater and secondly, the high must be centered in The Great Australian Bight.
On our recent passage to Robe we paid particular attention to the approaching systems and chose one that had the required 1030 hPa centre pressure. This system should have delivered light to moderate winds, small swell and acceptable seas. What we failed to focus on was the location of the centre of this system. As you can see from the synoptic charts below, this system was centred very low, perhaps level with Tasmania.
Tuesday 12th August 2014
Wednesday 13th August 2014
Thursday 14th August 2014, depart for Robe 07:00
Friday 15th August 2014, arrive Robe 09:00
Consequently we received a little bit of a pounding from the SE. The winds were not strong and the swell was low, however the seas were 1-2 metres, short and frequent. The boat slammed and the wind was on the nose. These conditions did moderate at midnight on the 14th and indeed we came into Robe with no wind, long low swells and no seas. The experience does show however, that 'Highs can be too low'!
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