Weather in Saint Clair County

Calculated from weather data of Scott Air Force Base/Midamerica St. Louis (KBLV) between 2020 and 2024.

Maximum temperatures (°F)

Month	Average	2024	2023	2022	2021	2020
January	41.0	38.0	47.0	39.0	40.0	43.0
February	49.0	59.0	53.0	45.0	34.0	46.0
March	58.0	65.0	55.0	61.0	61.0	58.0
April	67.0	70.0	69.0	66.0	67.0	65.0
May	77.0		78.0	77.0	74.0	72.0
June	87.0		87.0	88.0	87.0	87.0
July	89.0		89.0	90.0	86.0	89.0
August	86.0		86.0	86.0	88.0	84.0
September	82.0		82.0	81.0	83.0	80.0
October	69.0		70.0	69.0	72.0	66.0
November	55.0		58.0	57.0	56.0	61.0
December	49.0		52.0	47.0	56.0	47.0
Average	66.0	58.0	69.0	68.0	68.0	67.0

Average highest temperature per day

The maximum temperature is typically observed some hours after noon.

Minimum temperatures (°F)

Month	Average	2024	2023	2022	2021	2020
January	26.0	25	32	20	28	29
February	29.0	34	32	23	20	28
March	38.0	41	36	37	40	41
April	46.0	51	45	45	45	44
May	57.0		56	59	53	55
June	65.0		63	66	67	65
July	68.0		68	72	68	71
August	66.0		68	67	67	66
September	61.0		60	59	60	58
October	48.0		48	44	54	45
November	35.0		36	35	35	40
December	31.0		36	31	35	28
Average	46.0	38.0	48.0	47.0	48.0	48.0

Average lowest temperature per day

The minimum temperature is typically observed just before sunrise.

Cold and hot days

Number of days	2024	2023	2022	2021	2020
86 °F or warmer	0	59	64	68	54
77 °F or warmer	15	161	141	146	135
68 °F or warmer	36	194	195	192	182
32 °F or colder	37	57	84	73	72

Precipitation (%)

Month	Average	2024	2023	2022	2021	2020
January	11.6	14	10	11	16	10
February	10.7	4	9	25	10	14
March	9.4	8	11	13	8	9
April	9.3	14	2	13	8	9
May	6.3		3	8	6	8
June	3.7		3	6	2	4
July	5.0		7	11	3	4
August	4.3		5	4	2	3
September	3.9		3	6	4	3
October	6.9		10	11	5	6
November	4.8		7	4	0	5
December	8.1		17	7	6	4
Average	7.2	10.0	6.7	9.9	5.4	6.4

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 (miles per hour)

Month	Average	2024	2023	2022	2021	2020
January	9.2	8	10	11	8	7
February	9.1	10	9	10	10	9
March	10.2	11	12	12	9	8
April	9.7	11	10	11	9	8
May	7.9		7	9	8	7
June	6.7		7	6	7	6
July	5.6		7	6	5	5
August	5.8		6	6	6	5
September	5.9		6	6	8	5
October	8.5		10	9	9	7
November	8.3		8	9	9	7
December	8.4		9	8	9	8
Average	8.1	10.1	8.3	8.3	7.9	6.7

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	W	W	W	W	W
February	NW	SW	W	NW	NW
March	SW	SW	SW	SE	W
April	SW	SW	S	SW	W
May		NE	S	S	NE
June		N	SW	SW	S
July		SW	S	E	SE
August		W	SW	S	NE
September		W	NW	SW	S
October		W	W	SW	NW
November		W	SW	SW	SW
December		SW	S	SW	W

Prevailing wind direction

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

Saint Clair County weather Q&A

What is the warmest month in Saint Clair County?

The warmest month is July with an average temperature of 89 °F over the past years.

What is the coldest month in Saint Clair County?

The coldest month is January with an average daytime temperature of 41 °F in the past few years.

Which month is the wettest in Saint Clair County?

Chance of precipitation is the highest in January with a probability of around 11.6 %.

Which month is the driest in Saint Clair County?

The least rainfall and snow can be expected in June. The probability is about 3.8 %.