Jamestown in Summer
In summer (December, January and February), Jamestown sees average daytime highs around 23°C and overnight lows near 22°C, with 6 mm of rain over about 1 wet days across the season. It is the 2nd-warmest season and the 3rd-wettest season.
Over the season highs climb from about 21°C in early December to 24°C by late February. The sky is clear or mostly clear about 47% of the time across summer, and the air most often feels humid.
Summer is Jamestown's 2nd-best season to visit on our travel score. Jamestown has little temperature swing across the year, so its calendar seasons blur — the season framing matters less here than for a place with four distinct seasons. For the whole year in context, see Jamestown's year-round climate.
- Avg daytime high
- 23°C
- 2nd-warmest season
- Avg overnight low
- 22°C
- Rainfall
- 6 mm
- 1 wet days
- Avg wind
- 24 km/h
- Travel score
- 8.5
- 2nd-best season
- Months
- Dec · Jan · Feb
Temperature in Jamestown in Summer
Over the season highs climb from about 21°C in early December to 24°C by late February.
A typical summer day in Jamestown reaches about 23°C and drops to 22°C overnight. The warmest of the three months is February, the coolest December.
Jamestown weather by month
How the three summer months (December, January and February) compare with the rest of the year — the season's months are highlighted.
| Month | High / Low (°C) | Rainfall (mm) | Wet days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|
| Jan | 23° / 22° | 2 | 0.4 | 12.8 | 8.6 |
| Feb | 24° / 23° | 3 | 0.6 | 12.5 | 8.8 |
| Mar | 24° / 24° | 5 | 1.4 | 12.1 | 8.7 |
| Apr | 24° / 23° | 3 | 0.6 | 11.7 | 8.7 |
| May | 23° / 22° | 4 | 1.1 | 11.3 | 8.3 |
| Jun | 22° / 21° | 5 | 1.1 | 11.1 | 7.9 |
| Jul | 21° / 20° | 3 | 0.5 | 11.1 | 7.7 |
| Aug | 20° / 19° | 2 | 0.3 | 11.5 | 7.4 |
| Sep | 20° / 19° | 1 | 0.1 | 11.9 | 7.3 |
| Oct | 20° / 19° | 1 | 0.1 | 12.4 | 7.4 |
| Nov | 20° / 20° | 1 | 0 | 12.7 | 7.7 |
| Dec | 21° / 21° | 1 | 0 | 12.9 | 8.2 |
Cloud cover in Summer
The sky is clear or mostly clear about 47% of the time across summer.
Chance of precipitation in Summer
Jamestown gets around 6 mm of rain over 1 wet days across summer. The line is the day-by-day chance of measurable precipitation.
Humidity in Summer
Most of summer feels humid — the stacked bands show each day's mix of comfort levels, read off the dew point.
Wind in Summer
Winds average 24 km/h across summer.
Sunrise & sunset in Summer
Daylight runs from about 12 h 54 min in early December to 12 h 24 min by late February. The lit band spans sunrise to sunset each day.
Solar energy in Summer
Average shortwave solar energy reaching the ground each day across summer, about 7.0 kWh/m².
Is summer a good time to visit Jamestown?
Our two travel scores rate summer for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal), averaged across the three months.
summer is one of the better times to visit Jamestown for general sightseeing. The water and warmth also suit a beach or pool day.
What to pack for Jamestown in Summer
From summer's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In summer, Jamestown sees daytime highs around 23°C and nights near 22°C. Pack sun protection. Worth having: light clothes and a windbreaker.
Sea temperature near Jamestown in Summer
The nearest coast averages about 23°C across summer — the other half of the beach question. The full-year curve and swim-comfort zones are below.
The sea offshore is warmest in March at about 25°C and coldest in October near 20°C.
The water stays above 20°C all year — warm enough for a swim any month.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sea temperature (°C) | 23 | 24 | 25 | 25 | 24 | 23 | 22 | 21 | 20 | 20 | 21 | 22 |
| Comfort | Refreshing | Warm | Warm | Warm | Refreshing | Refreshing | Refreshing | Refreshing | Refreshing | Refreshing | Refreshing | Refreshing |
| Sea temperature (°C) | Comfort | |
|---|---|---|
| Jan | 23 | Refreshing |
| Feb | 24 | Warm |
| Mar | 25 | Warm |
| Apr | 25 | Warm |
| May | 24 | Refreshing |
| Jun | 23 | Refreshing |
| Jul | 22 | Refreshing |
| Aug | 21 | Refreshing |
| Sep | 20 | Refreshing |
| Oct | 20 | Refreshing |
| Nov | 21 | Refreshing |
| Dec | 22 | Refreshing |
UV index in Jamestown in Summer
Clear-sky midday UV across summer averages around 13 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in Jamestown peaks around January 20 at about 14 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near June 21 at about 8 (very high).
The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 14 | 13 | 13 | 11 | 9 | 8 | 8 | 8 | 10 | 11 | 13 | 12 |
| Level | Extreme | Extreme | Extreme | Extreme | Very high | Very high | Very high | Very high | Very high | Extreme | Extreme | Extreme |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 14 | Extreme |
| Feb | 13 | Extreme |
| Mar | 13 | Extreme |
| Apr | 11 | Extreme |
| May | 9 | Very high |
| Jun | 8 | Very high |
| Jul | 8 | Very high |
| Aug | 8 | Very high |
| Sep | 10 | Very high |
| Oct | 11 | Extreme |
| Nov | 13 | Extreme |
| Dec | 12 | Extreme |
Where is Jamestown?
Jamestown sits at 15.9°S, 5.7°W, 10 m above sea level, in Saint Helena. The nearest listed city is Tômbua, 1,878 km away.
Topography around Jamestown
How much the land rises and falls, and what covers it, within 3, 16 and 80 km of Jamestown.
Within 3 km, the terrain around Jamestown has significant variations in elevation — a maximum elevation change of 581 m around an average of 155 m above sea level; within 16 km, large variations in elevation — a maximum elevation change of 795 m; within 80 km, large variations in elevation — a maximum elevation change of 766 m.
The land around Jamestown is covered by water (44%) and shrubs (27%) within 3 km, water (85%) within 16 km, and water (97%) within 80 km.
Saint Helena travel facts
- Power plugs
- Type G
- 230 V · 50 Hz
Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.
Data sources
Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for Jamestown (-15.9249°, -5.7182°, elevation 10 m), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google.