Iriomote Weather in September
Iriomote in September averages 29°C (84°F) during the day and 27°C (81°F) at night. Keep in mind that quite a bit of rainfall is expected this month.
Rainfall in Iriomote in September
Climate statistics over the past 30 years suggest around 21 days of rain, with 241 mm (9.5 in) average for the month. Rain falls regularly this month and can be quite heavy when it does. Showers can be substantial, so waterproof gear is a good idea.
Temperature in Iriomote in September
If you're visiting Iriomote in September, expect highs of 29°C (84°F) and overnight lows around 27°C (81°F). The days can feel warmer than the evenings, so packing for both parts of the day is a good idea. At 27°C (81°F) overnight, the heat doesn't let up much after dark. If you're staying somewhere without air conditioning, a cold shower before bed and keeping the air moving can help.
Sunshine in Iriomote in September
With about 180 hours of sunshine, the area enjoys a nice balance of sun and overcast, creating a pleasant environment.If your ideal day consists of dry skies and pleasant temperatures, January, February, March, April, May, June, October, November and December typically offer the best circumstances for Iriomote.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Japan, check out our Iriomote's climate page.
Iriomote Temperature in September
Min Temperature
27°C (81°F)
Max Temperature
29°C (84°F)
Chance of Rain
70%
Precipitation
241 mm (9.5 in)
Rainy days
21 days
Humidity
80%
Sunshine
180 hours
Percentage Sunshine
Daily Historical Temperatures
50-year average (1976-2025)
Based on our historical records, temperatures in Iriomote typically stay consistent throughout September, with daily highs averaging around 29°C (84°F). Nights are warm, with lows around 26°C (79°F).
Average temperatures in September
Daily Historical Precipitation
50-year average (1976-2025)
Average daily rainfall for each day of the month based on long-term records.
Average precipitation in September
Historical weather for Iriomote in September
Browse day-by-day weather records for Iriomote spanning 51 years. Select any month and year to see actual temperatures, rainfall, and conditions recorded on each day.
Iriomote historical weather extremes in September
Based on 49 years of weather observations (1976-2025), these are the most extreme conditions recorded in Iriomote.
- The warmest day in September was on September 12, 2025, with a maximum of 34°C (93°F).
- On September 28, 2020, Iriomote saw its coldest September day with temperatures maxing out at 25°C (77°F).
- Nighttime temperatures dropped to 21°C (70°F) on September 27, 1997, marking the coldest September night on record.
Best Places in Japan in September
Find out more about the weather in Japan and which places have the best travel conditions in this month. See all of Japan in September →
perfect weather
pleasant
tolerable
unpleasant
poor
What to Wear in Iriomote in September
Warm but pleasant conditions in Iriomote in September. Focus on lightweight, maybe with natural fabrics, cotton blend shirts, comfortable shorts, and breathable footwear. A light cover-up for sun protection is smart too. It's going to pour! Pack a good poncho and prepare for very wet conditions. Bring sunglasses since you'll have some sunny periods throughout the monthWhat To Do in Iriomote in September
We rated the following activities from 1 (least suitable) to 10 (best) to do.
Check the conditions for any month of the year.
For a detailed overview over the year and the best time to visit Japan, check out our Iriomote's climate page.
Temperature Rainfall Sunshine Humidity
See the full Iriomote climate overview or explore weather in Japan.
