Southampton weather in May

In May, Southampton has daytime highs averaging 16 °C, nights around 8.7 °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 May

4° 12° 20° 18152229
Daily high Daily low Day of month on the horizontal axis. Highs peak at 17.7 °C and lows bottom out at 6.8 °C.

How May 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 May 14.8 °C 7.4 °C 31 %
11–20 May 15.7 °C 8.5 °C 32 %
21–31 May 17.2 °C 10.0 °C 33 %
0% 50% 100% 1 5 10 15 20 25 30
Chance of a wet day (over 1 mm) by date in May. Wettest date over the 30 years: May 10, at 57 %. Single dates are noisy — read the shape, not the spikes.

What to expect

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

Conditions in May

MeasureAverage
Mean temperature 12 °C
Record high (1991–2020) 25 °C
Record low (1991–2020) 1.0 °C
Relative humidity 76 %
Wind speed 20 km/h
Cloud cover 66 %

May compared with the months around it

Month Avg high Rainfall Cloud
March 10.2 °C 50 mm 70 %
April 12.9 °C 56 mm 64 %
May 16.0 °C 57 mm 66 %
June 18.7 °C 54 mm 66 %
July 20.7 °C 53 mm 62 %

See all twelve months for Southampton

QuestionsMay in Southampton, answered

How warm is Southampton in May?

Daily highs average 16 °C and nights fall to about 8.7 °C, a spread of 7.3 °C between afternoon and dawn. That makes May the 5th warmest month of the year here.

Does it rain much in Southampton in May?

May averages 57 mm of rain, spread over about 10 of the 31 days — 32 % of the month. Cloud cover averages 66 % of the sky.

How long are the days in May?

Southampton averages 16 hours between sunrise and sunset in May. 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.