Climate averages 1991–2020
Saint Helier weather
in May.
A cool, moderately wet month: the 6th warmest and the 3rd driest of the year.
Long-term climate patterns, not a forecast for a particular trip.
May is a cool month in Saint Helier: daytime highs average 13.7°C and nights cool to about 11.0°C. By daytime temperature it is the 6th warmest of the 12 months.
Expect about 53 mm of rain on roughly 9 days, which makes May a moderately wet month (the 3rd driest of the 12 months). Daylight, from sunrise to sunset, lasts about 15 h 17 min on an average May day.
The nearest other city in this atlas is Rennes (124 km away). In May its highs average 18.1°C, 4.4°C warmer than Saint Helier, with 63 mm of rain.
From May to June, average highs rise by 2.4°C to 16.1°C, and monthly rainfall falls from 53 mm to 50 mm.
The annual picture
May in context
Monthly rainfall
Average total · mmAverages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated
Every month, side by side
Saint Helier climate table
| Month | Average highHigh / low | Average low | Rainfall mm/month | Rain days ≥1 mm/day | Daylight hours/dayDaylight h/day |
|---|---|---|---|---|---|
| January | 9.1°C6.8°C | 6.8°C | 110 | 15.8 | 8.79 h |
| February | 8.7°C6.3°C | 6.3°C | 82 | 13.0 | 10.110 h |
| March | 9.7°C7.3°C | 7.3°C | 69 | 12.4 | 11.912 h |
| April | 11.3°C8.6°C | 8.6°C | 57 | 10.5 | 13.714 h |
| May, selected | 13.7°C11.0°C | 11.0°C | 53 | 9.4 | 15.315 h |
| June | 16.1°C13.4°C | 13.4°C | 50 | 8.7 | 16.216 h |
| July | 17.9°C15.4°C | 15.4°C | 48 | 9.1 | 15.816 h |
| August | 18.5°C16.1°C | 16.1°C | 63 | 9.8 | 14.414 h |
| September | 17.5°C15.1°C | 15.1°C | 77 | 11.0 | 12.713 h |
| October | 15.2°C12.9°C | 12.9°C | 122 | 15.5 | 10.811 h |
| November | 12.2°C10.0°C | 10.0°C | 132 | 17.6 | 9.29 h |
| December | 10.0°C7.7°C | 7.7°C | 138 | 16.7 | 8.38 h |
Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.
Compare places
May in nearby cities
- Rennes in MayFrance · 124 kmHigh 18.1°C · Low 9.5°C · 63 mm rain
- Caen in MayFrance · 127 kmHigh 17.3°C · Low 9.4°C · 58 mm rain
- Le Havre in MayFrance · 164 kmHigh 16.1°C · Low 10.1°C · 59 mm rain
- Poole in MayUnited Kingdom · 170 kmHigh 15.4°C · Low 9.5°C · 51 mm rain
- Bournemouth in MayUnited Kingdom · 171 kmHigh 15.5°C · Low 9.5°C · 51 mm rain
- Portsmouth in MayUnited Kingdom · 193 kmHigh 16.0°C · Low 9.0°C · 50 mm rain
- Brest, France in MayFrance · 196 kmHigh 15.0°C · Low 10.6°C · 59 mm rain
- Plymouth in MayUnited Kingdom · 197 kmHigh 15.0°C · Low 9.2°C · 61 mm rain
Read the numbers correctly
Climate, not a promise.
These patterns help compare months. They cannot tell you the weather on a specific day of your trip.
Sources, method and limitsHow these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Saint Helier) is explained once on the Saint Helier year overview and on the Sources, method and limits page.