What is the weather like in Key West in September?

Expect temperatures between 27°C and 29°C with 43% average rain probability and about 8 hours of sunshine daily.

What is the weather like in Key West in September?

Key West in September scores 52/100 based on 30 years of climate data. A reasonable choice for your trip.

Who should visit Key West in September?

September in Key West is ideal for: Cultural tourists, Business travelers.

Key West Weather in September | 30-Year Forecast

Avg High

29°C

Hottest around day 1

Avg Low

27°C

Coolest around day 22

Rainy Days

30days

43% avg rain chance

Sunshine

8hrs/day

Autumn season

Sea Temperature in September

Coastal Waters(Ocean)

30.8°C

Monthly Average

Water Feel

🌴Tropical

Perfect for swimming and water sports

Swim Rating

✅Excellent for swimming

Based on average sea surface temperature

Body of Water

Coastal Waters

Ocean

Key West coastline

Essential Travel Info for Key West

🗓️ Best Time to Visit 📖 Travel Guide 🍴 Food Guide

Currency

USD

$ United States dollar

Language

English

Driving

Right side

Safety

Moderate Safety

GPI: 2.44

Travel Intelligence

Exclusive flight analytics & health data for Key West

Smart Flight Estimator

Airport-to-Airport Logistics

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Flight Connectivity Analysis

Airport traffic data & seasonal patterns

Remote

16/ 100

Traffic Index

Off the beaten path

Peak Daily Arrivals

slots per day

Peak

Dec

Low

Jul

Monthly Traffic Distribution

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Traffic Level

Low Season

Key Connections

Miami (MIA)

Atlanta Hartsfield Jackson (ATL)

Charlotte Douglas (CLT)

Chicago O'Hare (ORD)

Washington Ronald Reagan National (DCA)

Health & Safety Advisory

CDC travel health recommendations

No Requirements

No Special Vaccinations Required

Standard travel precautions apply

Source: CDC Travelers' Health

View Complete Health Guide

Is September a Good Time to Visit Key West?

👌A reasonable choice for your trip(52/100)

Short Answer

⚠️ September falls in Key West's typhoon season. While daily weather averages 29°C with 43% rain, tropical storms can disrupt travel. Flexible bookings recommended.

Decision Factors

Atlantic Hurricane season active

Atlantic zone - expect potential atlantic hurricane activity

Oppressive heat and humidity

28.9°C with 78% humidity - challenging conditions

Feels significantly hotter than 28.9°C

Heat index: 34°C due to 78% humidity

Warm tropical seas

30.8°C sea temperature - Hot Soup

Plenty of sunshine

10.2h of sunshine daily

Shoulder season - balanced conditions

64% of peak - good value with moderate crowds

Good For

🏛️
Cultural tourists
Comfortable conditions for exploring museums and sites
💼
Business travelers
Climate-controlled meetings unaffected by weather

Who Should Avoid

👴
Elderly travelers
78% humidity creates difficult conditions
💼
Business travelers
Storm season may cause flight disruptions
🌡️
Heat-sensitive visitors
34°C feels-like temperature creates discomfort

"According to 30YearWeather's analysis of 30 years of NASA POWER satellite data,Key West in September averages 29°C with 43% precipitation probability."

📊 Source: 30YearWeather.com🛰️ Data: NASA POWER (1991-2021)View Methodology →

Frequently Asked Questions: Key West in September

What are the temperatures in Key West in September?

Daytime highs average 29°C, nights drop to 27°C. Temperatures remain fairly consistent.

How many rainy days in Key West in September?

Expect around 30 days with measurable rainfall. An umbrella is advisable.

What to wear in Key West in September?

Light, breathable fabrics. Don't forget sunglasses and a hat.

Is September peak season in Key West?

This is shoulder season—moderate prices and manageable crowds.

Key West Weather in September