Pekalongan weather in September

In September, Pekalongan has daytime highs averaging 31 °C, nights around 24 °C, with 14 wet days, and a sea temperature of 29 °C. Figures are 1991–2020 climate normals.

  1. Jan 26°
  2. Feb 26°
  3. Mar 26°
  4. Apr 26°
  5. May 27°
  6. Jun 26°
  7. Jul 26°
  8. Aug 26°
  9. Sep 27°
  10. Oct 27°
  11. Nov 27°
  12. Dec 26°

Daily temperatures through September

21°28°34°18152229
Daily highDaily low Day of month on the horizontal axis. Highs peak at 31.3 °C and lows bottom out at 23.2 °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.

DaysAvg highAvg lowChance of rain
1–10 September30.5 °C23.4 °C47 %
11–20 September30.9 °C23.6 °C39 %
21–30 September31.0 °C23.9 °C50 %
0%50%100%151015202530
Chance of a wet day (over 1 mm) by date in September. Wettest date over the 30 years: September 4, at 63 %. Single dates are noisy — read the shape, not the spikes.

What to expect

Measure Typical September Share of the month
Days above 25 °C 30 of 30 100 %
Days above 30 °C 20 of 30 68 %
Days below 0 °C 0 of 30 0 %
Days with more than 1 mm rain 14 of 30 45 %

Conditions in September

MeasureAverage
Mean temperature 27 °C
Record high (1991–2020) 35 °C
Record low (1991–2020) 20 °C
Relative humidity 74 %
Wind speed 8.2 km/h
Cloud cover 65 %

September compared with the months around it

Month Avg high Rainfall Cloud
July 29.4 °C 98 mm 61 %
August 30.0 °C 74 mm 60 %
September 30.8 °C 117 mm 65 %
October 30.6 °C 273 mm 74 %
November 29.4 °C 430 mm 86 %

See all twelve months for Pekalongan

Nearby destinations in September

Destination Avg high Wet days Sea
Pekalongan 31 °C 14 29
Pemalang 31 °C 12 29
Tegal 32 °C 9 29
Purwokerto 29 °C 13
Semarang 32 °C 6 29
Ungaran 31 °C 7 29
Salatiga 30 °C 7
Jepara 32 °C 6 29

QuestionsSeptember in Pekalongan, answered

How warm is Pekalongan in September?

Daily highs average 31 °C and nights fall to about 24 °C, a spread of 7.2 °C between afternoon and dawn. That makes September the 2nd warmest month of the year here.

Does it rain much in Pekalongan in September?

September averages 117 mm of rain, spread over about 14 of the 30 days — 45 % of the month. Cloud cover averages 65 % of the sky.

Is the sea warm enough to swim in September?

The sea averages 29 °C off Pekalongan 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?

Pekalongan averages 12 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.