Places › Key West, FL › September

Key West in September

A risky month — score 49 of 100

Typical September days in Key West reach about 89°F with nights near 79°F; rain is frequent — about 16 days see some rain, usually in showers. September is also the statistical peak of Atlantic hurricane season (the season runs June 1–November 30) — the averages hide that risk, so flexible plans matter.

Season note: September falls in Atlantic hurricane season (June 1–November 30), its statistical peak. That is climatology, not a forecast — but it is the one risk the averages cannot show.

What to pack for Key West in September

• A waterproof shell and shoes you can soak — rain falls on about 16 days in a typical September, so plan an indoor anchor each day.
• Swimsuit, sandals, and reef-safe sunscreen.

Every packing line is triggered by a number on this page — the rules are on How we pick.

September vs. the alternatives

The whole year in Key West

Averages are the 1991–2020 climate normals (NOAA National Centers for Environmental Information) for the station named on each page. Rain days = days with at least 0.01 in of precipitation. Daylight is computed for the middle of the month.