I have noticed today and yesterday that the forecast here, and other places I check frequently, both predicted westerly winds almost all day long. Yesterday afternoon the winds turned south east prolly @ 10mph+ similar to how they do in the summer and today they turned east earlier in the day but have remained light. Is there a particular reason why winds are so difficult to predict along the coast? I also forget why the SE winds pick up in the summer I know it has to do something with the land warming up or something, can anyone provide an explanation?

Thanks