I just read this that would explain why the wind always seem to calm down at night,
” if the days are very hot and windy. The wind will frequently die down in the evenings and fishing will become more pleasant.
Another consideration on the subject of wind is that during the day the wind may be blowing in off the sea. Then in the evening the wind dies down and blows back the other way. This change of wind direction is caused by land heating during the day and cooling at night, while the temperature of the sea remains constant. This effect happens a lot during the summer particularly on the West Coast. It means that the sea can be rough during the day and then flatten at night. This makes after dark the ideal time for surfcasting. “