climatesince.com

St. Louis County, MO

: September 2026 so far averaged 76.7°F in St. Louis County, MO, the warmest 1 to 29 September in the county average since the data begin in 1951 (county average from NOAA gridded data, 1951 to 2026).

Last updated . This page normally updates every day; the latest update is late.

High
81.3°F
Warmest since 2025
24th warmest of 76
Low
52°F
Warmest since 2025
37th warmest of 76

No measurable precipitation in the county average of St. Louis County, MO for 2 days to Tuesday 29 September 2026 (county average from NOAA gridded data, 1951 to 2026).

Every 29 September high of the county average in St. Louis County, MO since 1951: 81.3°F in 2026; the highest is 99.5°F, in 1953.
2025: 88.1°F1953: 99.5°F2026: 81.3°F 2026 81.3°F 1953 99.5°F since 2025 1951 2026
  • Normal range, 67.2 to 83.6°F
Every year as a table

Every 29 September low of the county average in St. Louis County, MO since 1951: 52°F in 2026; the lowest is 37°F, in 1951.

YearHigh, °FLow, °F
202681.352
202588.156.4
202475.565
202383.963.8
202266.541.6
202189.561.8
202068.348.2
201983.367.7
201876.550.7
201774.949.5
201667.253.1
201582.464.8
201484.455.5
201383.557.7
201270.248
201174.455
201074.950.5
200967.848.5
200882.757.4
20078454.5
200663.844.5
200578.146.1
200473.444.6
200362.239.5
200282.756.2
200167.844
200074.447.4
199978.152.5
199885.365.4
199772.454
199668.744.2
199579.951
199473.946
199371.743.2
199267.139.1
199180.453.7
199083.660.8
198975.243.3
198881.660.4
198779.959.1
198689.370.6
198576.348
198458.740.4
198383.354.1
198278.754.9
198173.950.7
19807047.3
197987.256.3
197872.444
19777453.5
19767150.5
197572.750.8
197468.944.8
197381.360.3
197281.655
197190.269.4
197074.547.7
196976.550.3
196880.452.1
196760.539
196671.249.9
196578.252.1
196471.343.1
196378.351
196270.839.2
196173.843.4
196079.948.5
195979.156.7
195868.543.9
195772.639.3
195686.554.3
195588.163.5
195484.869.7
195399.565.6
195291.655.3
195164.637

The month

August 2026 averaged 77.4°F in St. Louis County, MO, the warmest August in the county average since 2022, tied 47th warmest of 132 (with 1998, 1957 and 1935) (county average from NOAA's monthly county data, 1895 to 2026).

The month in words
  • Tuesday 29 September 2026: a high of 81.3°F averaged over St. Louis County, MO, the warmest 29 September in the county average since 2025, tied 24th warmest of 76 (with 1973) (county average from NOAA gridded data, 1951 to 2026).
  • Tuesday 29 September 2026: a low of 52°F averaged over St. Louis County, MO, the warmest 29 September night in the county average since 2025, 37th warmest of 76 (county average from NOAA gridded data, 1951 to 2026).
Days of the month without a value
0

Nearby

St Louis, MO 8.7 mi, the nearest city with its own station