Olongapo weather in September

In September, Olongapo has daytime highs averaging 29 °C, nights around 25 °C, with 27 wet days, and a sea temperature of 29 °C. Figures are 1991–2020 climate normals.

  1. Jan 25°
  2. Feb 26°
  3. Mar 27°
  4. Apr 29°
  5. May 28°
  6. Jun 27°
  7. Jul 27°
  8. Aug 27°
  9. Sep 27°
  10. Oct 27°
  11. Nov 27°
  12. Dec 26°

Daily temperatures through September

22°27°32°18152229
Daily highDaily low Day of month on the horizontal axis. Highs peak at 29.4 °C and lows bottom out at 24.7 °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.

DaysAvg highAvg lowChance of rain
1–10 September29.0 °C25.0 °C90 %
11–20 September28.7 °C24.9 °C95 %
21–30 September29.1 °C24.9 °C90 %
0%50%100%151015202530
Chance of a wet day (over 1 mm) by date in September. Wettest date over the 30 years: September 17, at 100 %. 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 6.9 of 30 23 %
Days below 0 °C 0 of 30 0 %
Days with more than 1 mm rain 27 of 30 92 %

Conditions in September

MeasureAverage
Mean temperature 27 °C
Record high (1991–2020) 33 °C
Record low (1991–2020) 23 °C
Relative humidity 90 %
Wind speed 15 km/h
Cloud cover 88 %

September compared with the months around it

Month Avg high Rainfall Cloud
July 29.0 °C 562 mm 89 %
August 28.7 °C 552 mm 91 %
September 28.9 °C 432 mm 88 %
October 29.6 °C 222 mm 72 %
November 29.7 °C 83 mm 59 %

See all twelve months for Olongapo

Nearby destinations in September

Destination Avg high Wet days Sea
Olongapo 29 °C 27 29
Angeles City 29 °C 28
San Fernando 29 °C 26
Mariveles 29 °C 26 29
Malolos 29 °C 27 29

QuestionsSeptember in Olongapo, answered

How warm is Olongapo in September?

Daily highs average 29 °C and nights fall to about 25 °C, a spread of 4.0 °C between afternoon and dawn. That makes September the 8th warmest month of the year here.

Does it rain much in Olongapo in September?

September averages 432 mm of rain, spread over about 27 of the 30 days — 92 % of the month. Cloud cover averages 88 % of the sky.

Is the sea warm enough to swim in September?

The sea averages 29 °C off Olongapo 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?

Olongapo 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.