What is the weather like in St. John's in September?

Expect temperatures between 26°C and 30°C with 38% average rain probability and about 8 hours of sunshine daily.

What is the weather like in St. John's in September?

St. John's in September scores 51/100 based on 30 years of climate data. A reasonable choice for your trip.

Who should visit St. John's in September?

September in St. John's is ideal for: Business travelers.

St. John's Weather in September | 30-Year Forecast

Avg High

30°C

Hottest around day 1

Avg Low

26°C

Coolest around day 19

Rainy Days

30days

38% avg rain chance

Sunshine

8hrs/day

Autumn season

Sea Temperature in September

Caribbean Sea

30.2°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

Caribbean Sea

St. John's coastline

Essential Travel Info for St. John's

🗓️ Best Time to Visit 📖 Travel Guide 🍴 Food Guide

Currency

XCD

$ Eastern Caribbean dollar

Language

English

Driving

Left side

Travel Intelligence

Exclusive flight analytics & health data for St. John's

Smart Flight Estimator

Airport-to-Airport Logistics

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Flight Connectivity Analysis

Airport traffic data & seasonal patterns

Remote

9/ 100

Traffic Index

Off the beaten path

Peak Daily Arrivals

slots per day

Peak

Jul

Low

Sep

Monthly Traffic Distribution

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Traffic Level

Low Season

Key Connections

Road Town Terrance B. Lettsome (EIS)

Saint Martin Princess Juliana (SXM)

New York John F Kennedy (JFK)

Miami (MIA)

Bridgetown Sir Grantley Adams (BGI)

Health & Safety Advisory

CDC travel health recommendations

7 Recommendations

COVID-19

All eligible travelers should be up to date with their COVID-19 vaccines. Please seeYour COVID-19 Vaccinationfor more information.

Hepatitis A

Recommended for unvaccinated travelers one year old or older going to Antigua and Barbuda.Infants 6 to 11 months old should also be vaccinated against Hepatitis A. The dose does not count toward the routine 2-dose series.Travelers allergic to a vaccine component should receive a single dose of immune globulin, which provides effective protection for up to 2 months depending on dosage given.Unvaccinated travelers who are over 40 years old, are immunocompromised, or have chronic medical conditions planning to depart to a risk area in less than 2 weeks should get the initial dose of vaccine and at the same appointment receive immune globulin.

Hepatitis B

Recommended for unvaccinated travelers of all ages traveling to Antigua and Barbuda.

Measles

Cases of measles are on the rise worldwide. Travelers are at risk of measles if they have not been fully vaccinated at least two weeks prior to departure, or have not had measles in the past, and travel internationally to areas where measles is spreading.All international travelers should be fully vaccinated against measles with the measles-mumps-rubella (MMR) vaccine, including an early dose for infants 6–11 months, according toCDC’s measles vaccination recommendations for international travel.

Rabies

Dogs infected with rabies are not commonly found in Antigua and Barbuda.If rabies exposures occur while in Antigua and Barbuda, rabies vaccines may only be available in larger suburban/urban medical facilities.Rabies pre-exposure vaccination considerations include whether travelers 1) will be performing occupational or recreational activities that increase risk for exposure to potentially rabid animals and 2) might have difficulty getting prompt access to safe post-exposure prophylaxis.Please consult with a healthcare provider to determine whether you should receive pre-exposure vaccination before travel.For more information, seecountry rabies status assessments.

Typhoid

Recommended for most travelers, especially those staying with friends or relatives or visiting smaller cities or rural areas.

+1 more

Source: CDC Travelers' Health

View Complete Health Guide

Is September a Good Time to Visit St. John's?

👌A reasonable choice for your trip(51/100)

Short Answer

Tropical storm season is active in St. John's during September. Average conditions (30°C, 38% rain) can be interrupted by severe weather. Monitor forecasts closely.

Decision Factors

Atlantic Hurricane season active

Atlantic zone - expect potential atlantic hurricane activity

Oppressive heat and humidity

29.6°C with 78% humidity - challenging conditions

Vaccinations required

Yellow Fever

Feels significantly hotter than 29.6°C

Heat index: 36°C due to 78% humidity

Warm tropical seas

30.2°C sea temperature - Hot Soup

Seismically active region

18 earthquakes recorded in this month (30-year data)

Good For

💼
Business travelers
Climate-controlled meetings unaffected by weather

Who Should Avoid

👴
Elderly travelers
Heat index of 36°C poses health risks
💼
Business travelers
Storm season may cause flight disruptions
🌡️
Heat-sensitive visitors
36°C feels-like temperature creates discomfort

"According to 30YearWeather's analysis of 30 years of NASA POWER satellite data,St. John's in September averages 30°C with 38% precipitation probability."

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

Frequently Asked Questions: St. John's in September

What are the temperatures in St. John's in September?

Daytime highs average 30°C, nights drop to 26°C. Temperatures remain fairly consistent.

How many rainy days in St. John's in September?

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

What to wear in St. John's in September?

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

Is September peak season in St. John's?

This is shoulder season—moderate prices and manageable crowds.

St. John's Weather in September