Mild
Average highs are around 21°C, so days are mild rather than hot.
September verdict
Saint Helena, Ascension and Tristan da Cunha in September
Weather score68Good
Good for holiday weather
Average highs are around 21°C, so days are mild rather than hot. Sunshine averages 0h per day, so this is not one of the brighter months. Rainfall averages 4mm, which is relatively low for holiday planning.
September weather
Monthly averages
Temp
21°C
Rain
4mm
Sun
0h
Sea
20°C
Weather score
68
Good
Seasonal climate calendar
TemperatureTemp
RainRain
SunSun
SwimSwim
Weather scoreWeather score
Trip feel
Drier
Rainfall averages 4mm, which is relatively low for holiday planning.
Limited sun
Sunshine averages 0h per day, so this is not one of the brighter months.
Cool sea
Sea temperatures average 20°C, so the water can feel cool.
Map
Weather map
Compare Saint Helena, Ascension and Tristan da Cunha with nearby places by weather score, rain, sun, temperature, and swim conditions.
Temperature
September21°C average high
September is cooler than the yearly average, which can make sightseeing feel gentler than in hotter months.
Warmest monthsJanuary to April
This stretch sets the upper range for average daytime heat.
Rain
September4mm average rain
September is close to Saint Helena's usual rainfall pattern, with little seasonal change across the year.
Driest monthsAll year
Rainfall stays comparatively low through the year.
Sun
September0 hours average sun
September is close to Saint Helena's usual sunshine level, with limited seasonal swing across the year.
Brightest monthsAll year
Sunshine stays consistently strong through the year.
Sea temperature
September20°C average sea
September is one of the coolest sea months, so the water may feel fresher than in peak months.
Warmest seaFebruary to May
Sea temperatures are usually near 25°C in this stretch, so swimming comfort is at its strongest.
Weather score
September68 weather score
September is one of the weakest weather-score months, when the overall mix is less favourable than the rest of the year.
Best weather monthsJanuary to April
These months have the strongest weather score in the monthly averages.