December through April is the long, dry stretch that built the islands’ reputation. Trade winds settle to a steady 12–18 knots, visibility underwater pushes past 100 feet, and rainfall averages under 40 mm a month. It is the high season for diving the North Wall, sailing North Sound and chartering for day-trips to Stingray City — book accommodation and dive boats months in advance.

Late April through early June is the quietest pocket of the calendar for low rainfall, before the wet season builds. Sunshine averages 9.5 hours a day in April; trade winds are still reliable, and hurricane risk is negligible. Hotel rates have begun their shoulder-season descent and the dive sites are uncrowded — arguably the best value-for-conditions window of the year.

August, September and October are the months to plan around. The climatological probability of a named storm passing within 75 nautical miles of Grand Cayman peaks near 50 % in September and remains elevated through October. If you must travel in this window, build flexibility into your itinerary, take out travel insurance that covers named storms specifically, and watch the National Hurricane Center cone in the days before departure. Our hurricane-season page tracks active advisories and Cayman-specific impacts.

November is the underrated bargain. By the second half of the month the season is winding down, the rains have eased, the crowds have not yet arrived for Christmas, and rates remain at shoulder-season levels. For travellers who can read a forecast and accept a small residual storm risk, it is the single best value month on the Cayman calendar.

Climate normals are the boring pages most weather sites bury behind a chart widget. We keep them on the front of the Weather Desk because almost every important decision a Cayman resident or visitor makes — when to fly, when to insure, when to close on property, when to launch a charter — is, in the end, a bet on a thirty-year average. This page is that average, on record, sourced and maintained.