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Key West, USA · Temperate oceanic

Key West in September: go or not?

Mixed period. Key West in September: 5.1/10.

📅 Updated August 2026 🛰️ ERA5 · 10 years 📍 24.56°N · 81.78°W
⚡ This month's verdict
Why not
Key West · September
5.1
27–29°
Temperature
65%
Rain
9h
Sun
🌊 Seaside☀️ Bright🍴 Gastronomy
Photo : Pavel Reyes Valdes via Unsplash
The month in detail

What to expect in September

Autumn marks the end of peak season in Key West. Temperatures drop (29.0°C) and rain returns (65.0% of days). With 65.0% of rainy days, always have indoor alternatives planned.

September ranks 12 out of 12 months in Key West. Compared to August: 6 pts more rainy days, −0.9h of sun per day.

This month's conditions

What it's like in September

UV index
8 · high
sunscreen and hat advised
Feels like
oppressive heat
24°
Sea
31°C
warm, ideal
Daylight
12.1h of daylight
Air quality
good
AQI 23
Compare

Is September the right month?

The best month in Key West is March (8.9/10), 3.8 pts higher than September.

See March →See all 12 months →
Context

Our verdict

Key West, the southern tip of the Florida Keys: 25,000 inhabitants 150 km from Cuba (the southernmost "continental USA", Mile 0 marker on US-1). Bohemian island, Caribbean atmosphere, Hemingway heritage.

Read Gilles' full review →

Book

Plan your trip

Hotels at their lowest outside peak season, highest on comfortable months. Shoulder seasons offer a good price/climate compromise.

🏨
Stay
Hotels & rentals · Key West
Expedia →
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Activities
Tours, tickets, experiences
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Flights
Multi-airline comparator
Kiwi →

🎟️ Activities & tours · Key West

GetYourGuide selection · free cancellation

See all →
Affiliate link · GetYourGuide
Practical info

What you need to know before you go

Three angles: the country (language, currency, safety, budget), the year-round climate, and the specifics of a beach holiday.

Country · USA

🗣️LanguageEnglish
💶CurrencyUS Dollar ($)
🚗DrivingRight-hand
🛡️Safety ⓘVery safe · 1/5
💰Cost of living ⓘExpensive · 4/5

🌡️ Climate

🌍Climate typeTemperate oceanic
📈Climate trend ⓘStable
🔥Hottest monthJuly · 30°C
❄️Coolest monthJanuary · 23°C
🌧️Rainiest month ⓘSeptember · 65%

🏖️ Beach holiday

📅Peak seasonJuin → Sept
🏖️Swell (Sept–Mar) ⓘModérée
Explore

Other destinations in September

If September doesn't convince you for this destination, compare with others.

Similar climate
HavanaCubaIsla HolboxMexicoNassauBahamasBahamasBahamasPlaya del CarmenMexico
Nearby
MiamiUnited States209 kmTrinidadCuba358 kmOrlandoUSA444 kmCayman IslandsCayman Islands586 km
Other top picks
Cape VerdeCape Verde5.3SalCape Verde5.6Marsa AlamEgypt5.8Sharm el-SheikhEgypt5.8HurghadaEgypt5.9
← AugustOctober →
🗺️ See all 754 destinations on the map
Location

Where is Key West ?

Global position + regional geographic context.

🌍 World
🔍 Geographic context
USA
Temperate oceanic climate with a 8.9 → 5.1 gap between best and worst month. 10 years of ERA5 data to choose by project.
24.56°N · 81.78°W
Questions

Frequently asked questions

What is the best time to visit Key West?
March is the best month with 25.0°C highs, 23.0°C lows, 10.0h of sunshine and 14.0% rainy days. The months of March & April offer comparable conditions.
How many hours of sunshine does Key West get in March?
Key West averages 10.0 sunshine hours per day in March. It is the sunniest month with a climate score of 8.5/10.
What is the rainiest month in Key West?
September is the most unfavourable month with September has the lowest climate score of the year and the lowest climate score of the year.
What are the temperatures at night in Key West in March?
In March, overnight lows reach 23.0°C, while afternoon highs average 25.0°C.
Is Key West good in winter?
In winter (December-February), Key West scores 7.7/10 on average — Decent period conditions for cultural visits.. The best month overall remains March with a score of 8.5/10.
When should you avoid Key West?
September is the most difficult month to visit Key West, with September has the lowest climate score of the year. Climate conditions are at their lowest of the year during this period.
Can you swim in Key West in September?
In September, the sea averages 31°C in Key West: warm, ideal. Ideal conditions for swimming and snorkeling.
Do you need sun protection in Key West in September?
The average UV index reaches 8 in September in Key West (high), with about 12.1h of daylight. Sunscreen and hat advised.