Ascension Auxiliary Air Force Airport

FHAW · Ascension, Saint Helena

Climate Ascension Auxiliary Air Force Airport 2020-2024

Climate and trends: average temperature, flight conditions, precipitation, wind speed and direction.

Calculated from historical METAR data of Ascension Auxiliary Air Force Airport (FHAW) between 2020 and 2024.

VFR conditions (%)

Month Average 2024 2023 2022 2021 2020
January 97.7 99 100 100 100 100
February 96.1 96 100 100 100 100
March 96.0 96 93 94 97 100
April 96.4 97 92 96 99
May 96.8 95 100 100 100
June 97.6 97 94 100 100
July 94.8 91 99 100 100
August 94.8 95 97 92 100
September 87.6 84 100 87 100
October 86.3 77 100 95 97
November 87.5 72 92 94 92
December 90.2 96 98 81 98
Average 94.6 97.0 89.4 97.3 95.1 98.4

1st best VFR conditions of Saint Helena

VFR conditions during daylight period

Percentage of observations where the VFR minimums for ceiling and visibility are met: visibility of 8 km or more and a ceiling of 3,000 ft or more. Only observations between sunrise and sunset are taken into account.

Marginal VFR conditions (%)

Month Average 2024 2023 2022 2021 2020
January 99.6 100 100 100 100 100
February 99.3 99 100 100 100 100
March 99.0 98 100 99 98 100
April 99.8 99 100 100 100
May 99.8 99 100 100 100
June 99.8 100 99 100 100
July 99.8 100 100 100 100
August 99.5 99 100 99 100
September 98.3 99 100 98 100
October 99.1 100 100 99 100
November 99.5 100 99 100 100
December 99.1 100 100 98 100
Average 99.4 98.9 99.6 99.6 99.3 100.0

Marginal VFR conditions or better during daylight period

Percentage of observations where the MVFR minimums for ceiling and visibility are met: visibility of 5 km or more and a ceiling of 1,000 ft or more. Only observations between sunrise and sunset are taken into account.

Maximum temperatures (°C)

Month Average 2024 2023 2022 2021 2020
January 28.0 29 28 27 27 28
February 28.8 30 28 28 28 29
March 29.3 30 29 29 28 29
April 29.0 29 28 29 29
May 28.5 29 28 28 28
June 27.5 27 27 27 28
July 26.5 26 27 27 27
August 25.9 26 26 27 25
September 25.4 25 26 25 24
October 25.6 26 26 26 26
November 26.2 26 26 27 26
December 26.6 28 27 25 26
Average 27.4 29.8 26.9 27.0 26.8 27.0

1st highest temperature of Saint Helena

Average highest temperature per day

The maximum temperature is typically observed some hours after noon.

Minimum temperatures (°C)

Month Average 2024 2023 2022 2021 2020
January 24.9 25 26 25 24 26
February 25.4 27 26 26 25 27
March 26.1 27 26 25 26 27
April 26.0 26 26 26 25
May 25.6 26 26 26 26
June 24.3 24 23 23 25
July 23.4 24 24 24 24
August 23.0 23 23 24 23
September 22.5 22 23 23 23
October 22.9 23 23 24 23
November 23.3 23 23 23 23
December 23.6 25 23 24 23
Average 24.5 26.3 24.0 24.1 24.3 24.4

1st lowest temperature of Saint Helena

Average lowest temperature per day

The minimum temperature is typically observed just before sunrise.

Precipitation (%)

Month Average 2024 2023 2022 2021 2020
January 4.1 1 6 2 0 9
February 10.6 14 13 2 17 0
March 7.7 14 17 15 14 0
April 5.3 3 15 2 11
May 5.9 4 9 2 12
June 8.9 9 26 0 13
July 7.9 6 16 3 0
August 8.0 11 7 17 1
September 18.6 26 1 40 0
October 11.1 15 0 14 9
November 7.4 3 10 13 9
December 13.6 9 4 52 13
Average 9.1 9.2 10.3 9.1 13.7 7.2

Precipitation during daylight period

Percentage of observations with observed rain, drizzle, snow or hail. Only observations between sunrise and sunset are taken into account.

Wind speed (knots)

Month Average 2024 2023 2022 2021 2020
January 13.7 14 15 13 13 14
February 13.5 13 14 13 14 15
March 13.3 13 12 14 14 14
April 14.1 14 14 15 13
May 13.8 14 12 14 14
June 14.3 15 13 14 14
July 14.5 15 15 14 14
August 14.0 13 14 14 16
September 13.9 14 13 12 14
October 13.6 14 13 14 14
November 13.7 13 13 14 14
December 14.1 14 13 15 14
Average 13.8 13.2 13.8 13.4 13.8 14.1

1st highest wind speed of Saint Helena

Average wind speed

Excluding wind gusts. Only observations between sunrise and sunset are taken into account.

Prevailing wind direction

Month 2024 2023 2022 2021 2020
January 144° 145° 149° 153° 144°
February 141° 139° 143° 143° 152°
March 139° 139° 143° 141° 148°
April 143° 145° 140° 142°
May 138° 138° 139° 141°
June 140° 139° 144° 141°
July 139° 135° 140° 142°
August 139° 141° 135° 136°
September 138° 136° 137° 143°
October 140° 143° 138° 140°
November 147° 144° 142° 137°
December 142° 143° 138° 146°

Prevailing wind direction

Average wind direction, weighed by wind speed. Only observations between sunrise and sunset are taken into account.