Kushiro weather in September

In September, Kushiro has daytime highs averaging 19 °C, nights around 14 °C, with 11 wet days, and a sea temperature of 17 °C. Figures are 1991–2020 climate normals.

  1. Jan -5°
  2. Feb -5°
  3. Mar -1°
  4. Apr 4°
  5. May 8°
  6. Jun 12°
  7. Jul 16°
  8. Aug 18°
  9. Sep 16°
  10. Oct 11°
  11. Nov 5°
  12. Dec -1°

Daily temperatures through September

9° 16° 23° 18152229
Daily high Daily low Day of month on the horizontal axis. Highs peak at 20.6 °C and lows bottom out at 11.7 °C.

How September develops

Averages for the first, middle and last part of the month, from daily 1991–2020 normals. Chance of rain is the share of years in which that calendar day recorded more than 1 mm.

Days Avg high Avg low Chance of rain
1–10 September 19.9 °C 15.8 °C 42 %
11–20 September 18.9 °C 14.3 °C 39 %
21–30 September 17.3 °C 12.4 °C 33 %
0% 50% 100% 1 5 10 15 20 25 30
Chance of a wet day (over 1 mm) by date in September. Wettest date over the 30 years: September 6, at 60 %. Single dates are noisy — read the shape, not the spikes.

What to expect

Measure Typical September Share of the month
Days above 25 °C 0.2 of 30 1 %
Days above 30 °C 0 of 30 0 %
Days below 0 °C 0 of 30 0 %
Days with more than 1 mm rain 11 of 30 38 %

Conditions in September

MeasureAverage
Mean temperature 16 °C
Record high (1991–2020) 26 °C
Record low (1991–2020) 4.8 °C
Relative humidity 84 %
Wind speed 21 km/h
Cloud cover 68 %

Where Kushiro ranks in September

Ranking Position Value
The coolest places in Asia in September 19th of 50 19 °C

September compared with the months around it

Month Avg high Rainfall Cloud
July 18.3 °C 124 mm 83 %
August 20.4 °C 151 mm 80 %
September 18.7 °C 160 mm 68 %
October 14.0 °C 114 mm 51 %
November 7.8 °C 75 mm 45 %

See all twelve months for Kushiro

QuestionsSeptember in Kushiro, answered

How warm is Kushiro in September?

Daily highs average 19 °C and nights fall to about 14 °C, a spread of 4.5 °C between afternoon and dawn. That makes September the 2nd warmest month of the year here.

Does it rain much in Kushiro in September?

September averages 160 mm of rain, spread over about 11 of the 30 days — 38 % of the month. Cloud cover averages 68 % of the sky.

Is the sea warm enough to swim in September?

The sea averages 17 °C off Kushiro in September. Most people find water below 20 °C bracing and above 25 °C comfortable for a long swim; this figure is a monthly surface average, so a sheltered bay on a still afternoon can be warmer.

How long are the days in September?

Kushiro averages 13 hours between sunrise and sunset in September. Day length is computed from latitude and date, so it is exact rather than modelled — but it says nothing about how much of that time is sunny.

Data sources and method

Normal period
1991–2020
Dataset version
era5-1991-2020-scores1.1
Last processed

Measured values come from ERA5 reanalysis and are reproduced unchanged. Calculated by us: daylight hours, beach and comfort scores, monthly rankings, threshold day counts, chance of a wet day by date, ten-day averages within the month. Full formulas are on the methodology page.

Contains modified Copernicus Climate Change Service information 2026. Neither the European Commission nor ECMWF is responsible for any use that may be made of the Copernicus information or data it contains.