What is the weather like in Sumba in September?

Expect temperatures between 23°C and 32°C with 6% average rain probability and about 8 hours of sunshine daily.

What is the weather like in Sumba in September?

Sumba in September scores 66/100 based on 30 years of climate data. Recommended for planning your trip.

Who should visit Sumba in September?

September in Sumba is ideal for: Beach lovers, Photographers, Honeymoon couples, Business travelers.

Sumba Weather in September | 30-Year Forecast

Avg High

32°C

Hottest around day 27

Avg Low

23°C

Coolest around day 1

Rainy Days

0days

6% avg rain chance

Sunshine

8hrs/day

Autumn season

Sea Temperature in September

Indian Ocean(Samudra Hindia)

27.6°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

Indian Ocean

Samudra Hindia

Sumba coastline

Essential Travel Info for Sumba

🗓️ Best Time to Visit 📖 Travel Guide 🍴 Food Guide

Currency

IDR

Rp Indonesian rupiah

Language

Indonesian

Driving

Left side

Connect

Since Sumba is far from other major citi...

Safety

High Safety

GPI: 1.8

Travel Intelligence

Exclusive flight analytics & health data for Sumba

Smart Flight Estimator

Airport-to-Airport Logistics

unlock smart flight estimates

Add your home location in settings to see airport details.

Flight Connectivity Analysis

Airport traffic data & seasonal patterns

Remote

4/ 100

Traffic Index

Off the beaten path

Peak Daily Arrivals

slots per day

Peak

Jul

Low

May

Monthly Traffic Distribution

Jan

Feb

Mar

Apr

May

Jun

Jul

Aug

Sep

Oct

Nov

Dec

Traffic Level

Low Season

Key Connections

Denpasar-Bali Island Ngurah Rai (Bali) (DPS)

Kupang-Timor Island El Tari (KOE)

Mataram Bandara Lombok (LOP)

Surabaya Juanda (SUB)

Health & Safety Advisory

CDC travel health recommendations

11 Recommendations

COVID-19

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

Chikungunya

All travelers should take steps to prevent mosquito bites. Chikungunya vaccination is generally not recommended. Travelers who wish to consider vaccination can visit “What to consider before traveling” on thechikungunya vaccinespage to learn more.

Hepatitis A

Recommended for unvaccinated travelers one year old or older going to Indonesia.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 Indonesia.

Japanese Encephalitis

Recommended for travelers whoAre moving to an area with Japanese encephalitis to liveSpend long periods of time, such as a month or more, in areas with Japanese encephalitisFrequently travel to areas with Japanese encephalitisConsider vaccination for travelersSpending less than a month in areas with Japanese encephalitis but will be doing activities that increase risk of infection, such as visiting rural areas, hiking or camping, or staying in places without air conditioning, screens, or bed netsGoing to areas with Japanese encephalitis who are uncertain of their activities or how long they will be thereNot recommended for travelers planning short-term travel to urban areas or travel to areas with no clear Japanese encephalitis season.

Malaria

CDC recommends that travelers going to certain areas of Indonesia take prescription medicine to prevent malaria. Depending on the medicine you take, you will need to start taking this medicine multiple days before your trip, as well as during and after your trip. Talk to your doctor about which malaria medication you should take.Transmission areasAll areas of eastern Indonesia (the provinces of Maluku, North Maluku, East Nusa Tenggara, Papua, and West Papua), including the town of Labuan Bajo and the Komodo Islands in the Nusa Tenggara regionRural areas of Kalimantan (Borneo), West Nusa Tenggara (includes the island of Lombok), Sulawesi, and SumatraLow transmission in rural areas of Java, including Pangandaran, Sukabumi, and Ujung KulonNo malaria transmission in the cities of Jakarta (the capital) or UbudNo malaria transmission in the resort areas of Bali or Java, the Gili Islands, or the Thousand Islands (Pulau Seribu)Drug resistanceChloroquine (P. falciparumandP. vivax)SpeciesP. falciparum(60%)P. vivax(40%)P. knowlesi,6P. malariae, andP. ovale(rare)Recommended chemoprophylaxisAtovaquone-proguanil, doxycycline, mefloquine, tafenoquine3Updated April 23, 2025See footnotes

+5 more

Source: CDC Travelers' Health

View Complete Health Guide

Is September a Good Time to Visit Sumba?

👍Recommended for planning your trip(66/100)

Short Answer

Sumba in September tests even seasoned travelers: 32°C daytime temperatures and 71% humidity mean early mornings or evenings are your best windows for sightseeing.

Decision Factors

Vaccinations required

Yellow Fever

Feels significantly hotter than 31.6°C

Heat index: 40°C due to 71% humidity

Warm tropical seas

27.6°C sea temperature - Tropical Bath

Seismically active region

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

Peak tourist season

89% of annual peak - expect crowds and high prices

Excellent dry conditions

Only 6% rain probability - ideal for outdoor activities

Good For

🏖️
Beach lovers
27.6°C warm seas and 6% rain probability
📸
Photographers
11.3h sunshine, 57% clear skies for golden hour shots
💑
Honeymoon couples
Wedding score 98/100 with romantic weather conditions
💼
Business travelers
Climate-controlled meetings unaffected by weather

Who Should Avoid

💰
Budget travelers
Peak season means premium prices everywhere
👨‍👩‍👧‍👦
Families with children
40°C heat index dangerous for children
👴
Elderly travelers
Heat index of 40°C poses health risks
🌡️
Heat-sensitive visitors
40°C feels-like temperature creates discomfort

"According to 30YearWeather's analysis of 30 years of NASA POWER satellite data,Sumba in September averages 32°C with 6% precipitation probability."

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

Frequently Asked Questions: Sumba in September

What are the temperatures in Sumba in September?

Daytime highs average 32°C, nights drop to 23°C. Temperatures remain fairly consistent.

How many rainy days in Sumba in September?

Expect around 0 days with measurable rainfall. Rain is unlikely to disrupt plans.

What to wear in Sumba in September?

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

Is September peak season in Sumba?

This is shoulder season—moderate prices and manageable crowds.

Sumba Weather in September