Saint Helena, Ascension, and Tristan da Cunha · 714 people
Jan
Feb
Mar
Apr
May
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Aug
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Oct
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Dec
The year’s records
Annual mean 18°C · wettest around September · prevailing wind SE
Warmest
23.1 °C
Coldest
16.8 °C
Wettest
25%
Windiest
8.6 m/s
Prevailing
SE
7.1 m/s average
When this place is good five ratings · thirty-six ten-day sections · click a cell to read it
never good
never good
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Sep
Oct
Nov
Dec
Every reading
bars actual · line feels-like, °Cchance of rain, %wind speed, m/ssky covered, %
The average temperature in Jamestown over the whole year is 18°C. February is the hottest month, with highs of about 23°C; September is the coldest, with lows of about 15°C. Jamestown has no sharply defined rainy season: the chance of rain on a given day runs from 6% in December, the driest month, to 18% in September, the wettest. Winds in Jamestown are highest in September, averaging 7.7 m/s (28 km/h), and lightest in January, at 6.0 m/s (22 km/h). The prevailing wind is from the SE. The clearest skies in Jamestown come in February, when the sky is typically 70% covered; October is the cloudiest month, at 87%.
Month by month Jamestown climate by month: average temperatures year round · click a month to read it
Month
High
Low
Feels like
Chance of rain
Cloud
Wind
Being outside
Sun
Walking
January
22°C
19°C
19°C
11%
75%
6.0 m/s
88
1
80
February
23°C
20°C
21°C
12%
70%
6.1 m/s
89
6
72
March
23°C
20°C
21°C
15%
70%
6.2 m/s
87
7
68
April
22°C
20°C
20°C
14%
73%
6.1 m/s
87
5
72
May
21°C
19°C
19°C
11%
71%
6.1 m/s
87
2
83
June
19°C
17°C
16°C
13%
72%
6.3 m/s
74
0
86
July
18°C
16°C
14°C
16%
78%
6.9 m/s
44
0
80
August
17°C
15°C
13°C
17%
83%
7.3 m/s
30
0
82
September
17°C
15°C
13°C
18%
86%
7.7 m/s
23
0
77
October
18°C
15°C
13°C
11%
87%
7.3 m/s
35
0
84
November
19°C
16°C
15°C
6%
83%
6.9 m/s
59
0
86
December
20°C
17°C
16°C
6%
79%
6.9 m/s
79
0
88
High and low are the warmest and coolest of four readings a day — midnight, 6am, noon and 6pm — so a true overnight low can sit a degree or two under them. Chance of rain, cloud and wind are the day’s average; feels-like and the three ratings (each out of 100: Good from 55, Ideal from 80) are read at midday.
Seasons, and the year in short Jamestown weather by season
Year round, Jamestown has days of about 17°C at their warmest in September, its coolest month, and 23°C in February, its warmest; the coolest hours of the day run from 15°C to 20°C through the year, and the average temperature over the year is 18°C around the clock. Rain is most likely around September and least likely around December. Every figure here is a decade of observations blended into one representative year, so it reads as what this date is usually like, not a forecast for one particular day.
Jamestown weather in winterJune to August
High 18°CLow 16°CRain 15%
Winter in Jamestown has typical daily highs of about 18°C and lows of about 16°C, with a 15% chance of rain on a given day.
Jamestown weather in springSeptember to November
High 18°CLow 15°CRain 12%
Spring in Jamestown has typical daily highs of about 18°C and lows of about 15°C, with a 12% chance of rain on a given day.
Jamestown weather in summerDecember to February
High 21°CLow 19°CRain 10%
Summer in Jamestown has typical daily highs of about 21°C and lows of about 19°C, with a 10% chance of rain on a given day.
Jamestown weather in autumnMarch to May
High 22°CLow 19°CRain 13%
Autumn in Jamestown has typical daily highs of about 22°C and lows of about 19°C, with a 13% chance of rain on a given day.
When is the rainy season in Jamestown?
Jamestown has no sharply defined rainy season: the chance of rain on a given day runs from 6% in December, the driest month, to 18% in September, the wettest.
What time of year is Jamestown windiest?
Winds in Jamestown are highest in September, averaging 7.7 m/s (28 km/h), and lightest in January, at 6.0 m/s (22 km/h). The prevailing wind is from the SE.
What is the average temperature in Jamestown year round?
The average temperature in Jamestown over the whole year is 18°C. February is the hottest month, with highs of about 23°C; September is the coldest, with lows of about 15°C.