douglas sea state, beaufort force, waves, wave height, maritime arbitration award Home Publications Articles What is Good Weather? What is Good Weather? Articles Danielle Southey Published: May 07, 2019 Contact author Download article pdf     Image In a recent reported arbitration (London Arbitration 6/19), a Tribunal considered a good weather description which referred to both Douglas sea state and significant wave height in a charterparty performance warranty. Under a time charter trip from South Africa to China, Owners warranted the vessel’s performance in good weather conditions. The charterparty description of good weather was; “good weather conditions are understood to mean wind speeds of maximum beaufort force 4 (11-16 knots) and total- combined (sea and swell) significant wave height confined to limits of douglas sea state 3 (0.5-1.25 metres) with no adverse currents and no influence of swell.” Charterers relied on the reports of a weather routing company to allege breach of performance warranties during good weather and claimed damages of US$128,388.86. Owners argued there had been no good weather periods and so any underperformance claim was bound to fail. The arbitration tribunal considered whether the conditions fell within the charterparty good weather definition. “Significant wave height confined to limits of Douglas sea state 3 (0.5 – 1.25 metres)” The parties agreed that it was difficult to reconcile ‘significant wave height’ and ‘douglas sea state’ – the first being a single measure of the average of the highest third of the waves encountered and the second being a range of heights. However, the parties made opposing submissions on how the two phrases could be read together. Charterers contended that ‘significant wave height confined to limits of douglas sea state 3’ included conditions with a swell height of up to two metres. They said that the word ‘significant’ was evidently not intended to have its technical meaning. Charterers pointed