Sanibel can be enjoyed all year round.  Mid-December through mid-February are the coldest months and June thru the end of November are hurricane season.  Sanibel rarely see long spells of cold weather.  Officially, Key West is the only 'frost free' location in the continental US, but sitting in the warm Gulf, Sanibel and Captiva are nearly as mild.  Summers see typical afternoon thunderstorms and wet weather brings mosquitoes and the ubiquitous no-see-ums found all over Florida and Caribbean, where they're nicknamed 'flying teeth'.  Many consider March/April [peak season] and October/November [off or shoulder season depending on property] ideal weather months.   March sees the highest number of visitors to the islands.  September is usually the quietest month and some restaurants and other visitor services close for refurbishing or vacation and others operate on reduced scheduled. 

In August 2004 Sanibel and Captiva were hit by Hurricane Charley.   Captiva took the hardest hit but both islands lost their high canopy of Australian pines, a shallow rooted non-native species that had proliferated on the islands in the 70's and 80's.  Replanting projects are usually run in off-season months - July to September.

Shelling is best in the winter months.  The winds shift in the summer and fewer shells wash up unless a tropical storm system moves though the Gulf near enough to stir up the water.  Birding is also best in late fall and winter when migratory birds return or pass through Ding Darling Wildlife Refuge.

For historical weather averages click here .  For historical Gulf water temperatures click here.  Most of the year the sun is strong and the beaches have little or no shade.  Use high SPF sunscreen and beach umbrellas whenever possible. 

NOTE: The Gulf of Mexico has seen a number of serious outbreaks of two mico-organisms that impact beach areas, red tide and Red Drift Algae.  Both are more common in summer and early fall.  See the Red Tide/Red Drift Algae InsiderPage for more information.