Climate St. Athan Airport 2020-2024

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

Calculated from historical METAR data of St. Athan (EGSY) between 2020 and 2024.

VFR conditions (%)

Month	Average	2024	2023	2022	2021	2020
January	57.1	68	61	55	39
February	51.2	44	48	59	59
March	57.9	54	47	70	71
April	74.5		56	88	94
May	78.8		80	73	81
June	82.8		84	87	76
July	69.8		59	82	77	87
August	65.6		66	79	58	57
September	74.3		72	87	62	79
October	68.1		71	71	66	62
November	63.0		64	64	65	58
December	50.2		33	64	56	61
Average	65.0	54.6	63.7	74.1	67.9	64.6

70th best VFR conditions of United Kingdom

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	89.6	99	88	90	78
February	81.0	76	74	88	92
March	88.2	89	84	92	90
April	91.9		86	95	100
May	93.6		91	95	98
June	94.4		94	95	94
July	92.6		90	95	94	94
August	92.3		90	97	98	84
September	93.9		95	100	89	92
October	94.7		91	97	97	96
November	90.1		92	90	90	88
December	85.1		80	87	89	89
Average	90.5	87.5	88.7	93.9	92.8	90.0

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	8.0	8	9	8	7
February	9.4	10	10	10	8
March	10.8	11	10	12	10
April	12.6		12	14	12
May	15.8		18	16	14
June	20.0		22	19	19
July	20.7		19	22	21	20
August	20.6		19	24	19	20
September	19.1		21	18	20	18
October	15.4		16	17	16	14
November	11.7		11	13	11	12
December	8.8		10	6	9	9
Average	13.7	9.9	14.7	15.2	14.0	14.8

40th highest temperature of United Kingdom

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	3.6	3	3	4	4
February	5.6	6	4	7	5
March	6.5	5	5	8	7
April	7.2		5	9	7
May	10.8		9	13	11
June	14.6		13	16	15
July	16.5		14	18	18	17
August	16.3		13	19	16	17
September	14.4		14	15	16	14
October	11.3		11	11	13	11
November	8.0		6	8	8	9
December	5.6		7	1	7	7
Average	9.4	4.8	8.7	11.1	10.7	11.8

88th lowest temperature of United Kingdom

Average lowest temperature per day

The minimum temperature is typically observed just before sunrise.

Precipitation (%)

Month	Average	2024	2023	2022	2021	2020
January	13.0	8	15	9	22
February	18.2	27	12	19	14
March	14.9	13	27	9	5
April	9.2		16	3	3
May	9.7		6	9	19
June	4.6		4	5	6
July	10.5		17	4	7	4
August	9.4		11	5	7	15
September	9.7		12	11	6	9
October	14.0		13	8	11	30
November	14.2		18	15	10	12
December	18.0		28	9	11	17
Average	12.8	15.9	13.9	8.6	9.6	15.9

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	9.8	10	11	7	11
February	11.6	11	10	15	11
March	10.4	11	10	10	11
April	10.0		9	11	10
May	9.8		9	11	11
June	9.6		10	10	9
July	10.6		12	10	9	10
August	10.0		10	9	10	11
September	9.1		9	9	9	11
October	10.1		9	10	10	13
November	10.4		12	11	8	10
December	10.5		13	8	10	9
Average	10.3	10.5	10.1	10.0	10.1	10.9

40th highest wind speed of United Kingdom

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	250°	262°	280°	286°
February	254°	284°	258°	116°
March	216°	240°	086°	264°
April		125°	073°	066°
May		349°	245°	249°
June		042°	231°	260°
July		252°	251°	254°	255°
August		264°	270°	267°	236°
September		213°	273°	232°	285°
October		240°	213°	242°	270°
November		274°	230°	294°	226°
December		254°	078°	289°	242°

Prevailing wind direction

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