West Island weather in May

In May, West Island has daytime highs averaging 27 °C, nights around 26 °C, with 18 wet days, and a sea temperature of 28 °C. Figures are 1991–2020 climate normals.

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

Daily temperatures through May

23° 27° 30° 18152229
Daily high Daily low Day of month on the horizontal axis. Highs peak at 27.5 °C and lows bottom out at 25.7 °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 27.3 °C 26.0 °C 60 %
11–20 May 27.3 °C 26.1 °C 60 %
21–31 May 27.1 °C 25.9 °C 59 %
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 8, at 73 %. Single dates are noisy — read the shape, not the spikes.

What to expect

Measure Typical May Share of the month
Days above 25 °C 31 of 31 100 %
Days above 30 °C 0 of 31 0 %
Days below 0 °C 0 of 31 0 %
Days with more than 1 mm rain 18 of 31 60 %

Conditions in May

MeasureAverage
Mean temperature 27 °C
Record high (1991–2020) 29 °C
Record low (1991–2020) 24 °C
Relative humidity 82 %
Wind speed 32 km/h
Cloud cover 58 %

May compared with the months around it

Month Avg high Rainfall Cloud
March 27.5 °C 207 mm 64 %
April 27.5 °C 199 mm 62 %
May 27.3 °C 135 mm 58 %
June 26.8 °C 125 mm 58 %
July 26.3 °C 122 mm 59 %

See all twelve months for West Island

QuestionsMay in West Island, answered

How warm is West Island in May?

Daily highs average 27 °C and nights fall to about 26 °C, a spread of 1.3 °C between afternoon and dawn. That makes May the 4th warmest month of the year here.

Does it rain much in West Island in May?

May averages 135 mm of rain, spread over about 18 of the 31 days — 60 % of the month. Cloud cover averages 58 % of the sky.

Is the sea warm enough to swim in May?

The sea averages 28 °C off West Island in May. 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 May?

West Island averages 12 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.