St. Louis Lambert International Airport

KSTL · Missouri, United States

Climate St. Louis Lambert International Airport 2020-2024

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

Calculated from historical METAR data of St. Louis Lambert International Airport (KSTL) between 2020 and 2024.

VFR conditions (%)

Month Average 2024 2023 2022 2021 2020
January 58.1 46 56 84 51 50
February 72.1 91 80 67 71 64
March 72.7 70 77 82 62
April 85.4 95 85 89 81
May 84.0 86 77 83 78
June 93.1 93 94 92 94
July 92.1 90 89 90 91
August 90.6 77 89 97 95
September 92.4 97 89 93 87
October 77.5 81 87 67 73
November 80.5 89 79 94 88
December 70.6 60 58 72 81
Average 80.0 67.2 81.9 82.4 82.7 79.4

VFR conditions during daylight period

Percentage of observations where the VFR minimums for ceiling and visibility are met: visibility of 5 mi 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 80.6 71 83 93 77 75
February 87.5 94 94 81 91 85
March 90.9 90 97 90 88
April 94.4 99 95 94 94
May 94.7 97 93 95 91
June 97.9 96 99 98 99
July 96.9 97 94 97 98
August 97.6 93 97 99 100
September 97.1 100 94 97 94
October 91.2 94 91 88 90
November 93.8 99 94 100 98
December 90.1 83 82 88 99
Average 91.8 81.9 94.0 93.1 93.2 92.9

Marginal VFR conditions or better during daylight period

Percentage of observations where the MVFR minimums for ceiling and visibility are met: visibility of 3⅛ mi 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 5.6 4 9 5 5 6
February 9.7 16 12 8 1 8
March 14.2 14 16 17 15
April 20.0 22 20 20 19
May 25.7 27 26 24 23
June 31.0 31 32 31 31
July 32.5 33 34 31 33
August 30.7 31 31 32 30
September 28.6 29 27 29 27
October 21.0 22 21 23 19
November 13.5 16 14 14 17
December 9.8 12 8 14 9
Average 18.9 9.6 21.3 20.6 20.2 19.8

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 -3.5 -3 1 -6 -1 -1
February -1.0 3 1 -4 -6 -2
March 4.1 3 4 6 6
April 8.7 9 8 9 7
May 15.6 16 16 14 14
June 20.8 20 21 21 21
July 23.0 23 24 22 23
August 21.3 22 22 22 20
September 18.2 18 17 19 17
October 10.8 12 9 14 9
November 3.5 5 4 3 6
December 0.7 4 1 3 -1
Average 9.0 -1.7 11.1 10.1 10.6 10.0

Average lowest temperature per day

The minimum temperature is typically observed just before sunrise.

Precipitation (%)

Month Average 2024 2023 2022 2021 2020
January 16.3 22 14 9 22 16
February 14.8 3 9 28 23 19
March 14.8 16 18 12 15
April 10.1 1 17 10 9
May 7.9 4 10 8 12
June 3.3 3 2 4 4
July 5.0 3 12 4 6
August 3.3 6 4 1 2
September 2.6 0 7 5 2
October 9.8 10 9 13 11
November 7.1 5 3 1 5
December 10.9 17 13 7 5
Average 9.0 12.7 6.8 10.7 8.5 8.4

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 9.0 8 9 9 8 8
February 9.1 9 10 9 9 9
March 9.9 10 10 10 9
April 10.0 11 11 9 9
May 8.6 8 10 8 8
June 7.6 7 7 7 8
July 6.8 7 7 6 7
August 6.9 7 7 7 6
September 6.9 6 7 8 7
October 8.6 9 8 9 9
November 8.5 7 9 8 9
December 8.8 9 9 9 8
Average 8.3 8.2 8.2 8.6 8.1 8.0

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 266° 259° 293° 272° 243°
February 254° 245° 279° 333° 296°
March 250° 235° 149° 221°
April 232° 219° 246° 274°
May 105° 179° 172° 258°
June 005° 232° 211° 203°
July 254° 246° 275° 173°
August 267° 228° 188° 276°
September 166° 315° 209° 205°
October 259° 259° 233° 278°
November 242° 235° 244° 212°
December 228° 192° 221° 252°

Prevailing wind direction

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