Southampton weather in August

In August, Southampton has daytime highs averaging 21 °C, nights around 14 °C, with 9.8 wet days. Figures are 1991–2020 climate normals.

  1. Jan 6°
  2. Feb 6°
  3. Mar 7°
  4. Apr 9°
  5. May 12°
  6. Jun 15°
  7. Jul 17°
  8. Aug 17°
  9. Sep 15°
  10. Oct 12°
  11. Nov 9°
  12. Dec 6°

Daily temperatures through August

10° 17° 24° 18152229
Daily high Daily low Day of month on the horizontal axis. Highs peak at 21.6 °C and lows bottom out at 12.7 °C.

How August 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 August 21.2 °C 14.2 °C 32 %
11–20 August 20.6 °C 13.9 °C 31 %
21–31 August 19.9 °C 13.3 °C 32 %
0% 50% 100% 1 5 10 15 20 25 30
Chance of a wet day (over 1 mm) by date in August. Wettest date over the 30 years: August 25, at 53 %. Single dates are noisy — read the shape, not the spikes.

What to expect

Measure Typical August Share of the month
Days above 25 °C 2.0 of 31 6 %
Days above 30 °C 0.3 of 31 1 %
Days below 0 °C 0 of 31 0 %
Days with more than 1 mm rain 9.8 of 31 32 %

Conditions in August

MeasureAverage
Mean temperature 17 °C
Record high (1991–2020) 32 °C
Record low (1991–2020) 7.8 °C
Relative humidity 77 %
Wind speed 19 km/h
Cloud cover 64 %

August compared with the months around it

Month Avg high Rainfall Cloud
June 18.7 °C 54 mm 66 %
July 20.7 °C 53 mm 62 %
August 20.5 °C 65 mm 64 %
September 18.2 °C 55 mm 65 %
October 14.5 °C 76 mm 68 %

See all twelve months for Southampton

QuestionsAugust in Southampton, answered

How warm is Southampton in August?

Daily highs average 21 °C and nights fall to about 14 °C, a spread of 6.7 °C between afternoon and dawn. That makes August the 2nd warmest month of the year here.

Does it rain much in Southampton in August?

August averages 65 mm of rain, spread over about 10 of the 31 days — 32 % of the month. Cloud cover averages 64 % of the sky.

How long are the days in August?

Southampton averages 15 hours between sunrise and sunset in August. 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.