Is Koshimizu hot in September?
Days are typically mild at 20.7°C, while nights average 13°C.
Japan · 1991–2020 normal
Koshimizu in
September.
Typical September weather in Koshimizu: 20.7°C by day, 13°C at night, 127 mm of rain over 10 wet days. These are measured 1991–2020 station normals, not a forecast.
Typical high20.7°C
Typical low13°C
Rain127 mm
Wet days10
In the year-round weather comparison, September scores 66 out of 100 (July leads the year at 79). Daylight is calculated as 12 h 27 from latitude 43.86°. Open-water sea temperature is 16.6°C (30 km from the place centre).
September at a glance
What is Koshimizu like in September?
Plain answers from the measured climate record—not a forecast or a promise about a particular trip.
Does it rain much?
The measured monthly average is 127 mm across about 10 wet days.
How much daylight is there?
There are about 12 h 27 between sunrise and sunset at mid-month, calculated from the place latitude.
Is September a good time to visit?
September ranks 3 of 12 in our weather comparison; July ranks first.
The evidence behind this page
One month,
from the same station.
- Place identity
- GeoNames 2129447
- NOAA station
- JA000047409 · ABASHIRI
- Station distance
- 22.8 km from the place centre
- Coverage
- Good coverage · 17 usable years
- Important limit
- Historical climate is not a forecast. Nearby stations can miss mountains, coasts, and local microclimates.
Next step
Choose your month.
Then plan the details.
The weather comparison for Koshimizu is based on climate evidence, not payments from travel companies. Flight, accommodation and activity links will be clearly labelled when they are added; there are no booking offers on this page today.
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