Belmopan weather in September

In September, Belmopan has daytime highs averaging 30 °C, nights around 23 °C, with 25 wet days. Figures are 1991–2020 climate normals.

  1. Jan 22°
  2. Feb 23°
  3. Mar 25°
  4. Apr 27°
  5. May 27°
  6. Jun 26°
  7. Jul 26°
  8. Aug 27°
  9. Sep 26°
  10. Oct 25°
  11. Nov 23°
  12. Dec 23°

Daily temperatures through September

21° 28° 34° 18152229
Daily high Daily low Day of month on the horizontal axis. Highs peak at 31.2 °C and lows bottom out at 23.1 °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 30.8 °C 23.5 °C 79 %
11–20 September 30.5 °C 23.5 °C 82 %
21–30 September 29.8 °C 23.2 °C 86 %
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 8, at 90 %. 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 17 of 30 56 %
Days below 0 °C 0 of 30 0 %
Days with more than 1 mm rain 25 of 30 83 %

Conditions in September

MeasureAverage
Mean temperature 26 °C
Record high (1991–2020) 38 °C
Record low (1991–2020) 21 °C
Relative humidity 86 %
Wind speed 12 km/h
Cloud cover 77 %

September compared with the months around it

Month Avg high Rainfall Cloud
July 30.0 °C 132 mm 70 %
August 30.7 °C 130 mm 68 %
September 30.4 °C 159 mm 77 %
October 28.7 °C 185 mm 74 %
November 27.2 °C 130 mm 63 %

See all twelve months for Belmopan

QuestionsSeptember in Belmopan, answered

How warm is Belmopan in September?

Daily highs average 30 °C and nights fall to about 23 °C, a spread of 6.9 °C between afternoon and dawn. That makes September the 6th warmest month of the year here.

Does it rain much in Belmopan in September?

September averages 159 mm of rain, spread over about 25 of the 30 days — 83 % of the month. Cloud cover averages 77 % of the sky.

How long are the days in September?

Belmopan 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.