Wind
Offshore, onshore — the difference is everything.
Offshore vs onshore
Offshore wind blows from land to sea, holding the wave face up — that's the glass you dream about. Onshore blows the other way and crumbles it.
The terms
offshore land → sea, holds the face onshore sea → land, crumbles it cross-shore side-on, ruffles the surface glass no wind at all, pristine
Hourly
Wind changes through the day. Dawn is usually calmest — the reason dawn patrol exists.