Saint-Louis climate: monthly averages: annual mean temperature 26.4 C; warmest month Oct (29.1 C); coldest month Jan (22.4 C).
Annual mean temperature: 26.4 C
Warmest month: Oct (29.1 C)
Coldest month: Jan (22.4 C)
Wettest month: Aug (3.98 mm/day)
All-time record high: 43.0 C
All-time record low: 10.5 C
Everything below is collected in one spot so you do not have to cross-check Saint-Louis climate: monthly averages by hand. The gap between Jan and Oct is 6.7 C here: 22.4 C against 29.1 C. Precipitation peaks in Aug (3.98 mm/day) and bottoms out in May (0.00 mm/day), so a 2x difference between the two. Taken together that is roughly 378 mm of rain a year for the grid cell. Because each page is rebuilt independently, one unavailable upstream never takes the rest of the site down. Exact monthly values are in the table; links below cover adjacent locations and years.
Annual mean temperature 26.4 C
Warmest month Oct (29.1 C)
Coldest month Jan (22.4 C)
Wettest month Aug (3.98 mm/day)
All-time record high 43.0 C
All-time record low 10.5 C
Annual precipitation 380 mm / year
Coordinates 16.01793, -16.48962
Population 254,171
Average monthly temperature and rainfall in Saint-Louis
Month
Mean temp (C)
Rain (mm/day)
Record high (C)
Record low (C)
Jan
22.4
0.09
37.1
10.5
Feb
23.2
0.33
39.8
12.2
Mar
24.9
1.24
41.1
13.8
Apr
25.4
0.06
42.6
15.7
May
26.7
0.00
42.9
16.9
Jun
28.2
0.34
43.0
18.9
Jul
28.7
2.09
42.1
22.5
Aug
28.8
3.98
40.3
23.7
Sep
28.9
3.62
41.0
22.9
Oct
29.1
0.64
39.9
18.9
Nov
26.6
0.03
38.4
15.1
Dec
23.7
0.01
37.5
11.5
What the Saint-Louis climate table shows
Values are multi-decadal climatological averages for the 16.01793, -16.48962 grid cell, not a single year. Rain is the daily mean, so a value of 2.00 mm/day is about 60 mm across a 30-day month. Averages smooth over extremes, so use them for planning rather than for what to pack for next Tuesday.
Frequently asked questions
Why do the numbers differ from a weather app?
An app shows one location on one day. These are long-run averages, so they smooth out single hot or cold spells.
How much rain is 3.98 mm/day in a month?
Rain is recorded as a daily mean, so 3.98 mm/day is roughly 121 mm across a 30-day month.