We have no meanings for "become southwesterly" in our records yet.
1 The wind along the coast will be light to moderate easterly becoming southwesterly by evening.
2 The wind along the coast will be light northwesterly early morning, otherwise light to moderate westerly becoming southwesterly .
3 The Eastern half -Wind: The wind along the coast will be fresh to strong north-easterly ,becomingsouthwesterly overnight.
4 The wind along the coast will be strong northwesterly but moderate easterly in the south becoming southwesterly in the afternoon.
5 The wind along the coast will be fresh to strong northwesterly but moderate northeasterly along the south coast at first becoming southwesterly .
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