Weather in Jefferson County

Calculated from weather data of Jefferson County International Airport (K0S9) between 2020 and 2024.

Maximum temperatures (°C)

Month	Average	2024	2023	2022	2021	2020
January	8.1	7.7	8.0	7.5	8.5	9.0
February	7.6	9.6	7.4	8.5	7.4	8.8
March	10.8	11.3	10.5	11.0	10.8	9.5
April	13.4	13.5	12.0	12.4	14.8	14.1
May	17.7		19.8	14.4	16.6	18.0
June	20.1		20.6	19.3	22.6	18.8
July	22.9		23.6	23.3	23.3	21.8
August	23.7		24.3	25.1	23.3	22.8
September	20.3		19.8	21.6	19.3	21.3
October	14.8		15.3	17.8	13.5	14.9
November	10.0		10.1	8.0	11.0	10.3
December	7.5		9.8	4.9	5.2	8.9
Average	14.3	10.5	15.2	14.8	14.7	14.8

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	1.4	1	2	2	3	3
February	0.5	3	0	1	1	1
March	1.5	3	1	3	2	1
April	4.0	4	4	3	4	4
May	7.5		9	7	7	8
June	9.7		9	10	12	10
July	10.7		10	12	11	11
August	11.3		12	12	12	11
September	9.4		10	10	9	10
October	5.0		6	6	6	7
November	2.8		3	0	5	3
December	1.5		4	0	0	2
Average	5.1	2.7	5.8	5.5	5.8	5.8

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
30 °C or warmer	0	3	4	8	0
25 °C or warmer	0	22	26	20	15
20 °C or warmer	1	95	87	84	72
0 °C or colder	16	57	50	52	53

Precipitation (%)

Month	Average	2024	2023	2022	2021	2020
January	5.5	19	10	0	7	5
February	7.7	13	16	2	4	4
March	5.4	13	12	3	3	3
April	5.5	8	17	5	2	4
May	3.2		5	4	1	4
June	3.5		7	3	3	4
July	0.4		2	0	0	1
August	0.9		3	1	0	1
September	2.8		7	1	4	2
October	4.9		11	10	5	1
November	6.1		5	12	9	5
December	6.2		9	12	10	3
Average	5.0	12.9	8.5	3.8	3.4	2.9

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 (km/h)

Month	Average	2024	2023	2022	2021	2020
January	9.2	10	9	8	10	12
February	8.6	10	8	8	10	8
March	9.6	11	10	9	11	8
April	10.6	10	12	12	9	9
May	8.5		8	9	9	9
June	8.5		8	9	9	8
July	7.5		8	7	7	8
August	8.1		8	8	8	9
September	8.6		10	9	9	8
October	8.6		9	8	9	8
November	8.8		7	7	11	9
December	7.3		8	8	8	8
Average	8.8	10.0	8.8	8.6	9.1	8.5

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

Prevailing wind direction

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

Jefferson County weather Q&A

What is the warmest month in Jefferson County?

The warmest month is August with an average temperature of 24 °C over the past years.

What is the coldest month in Jefferson County?

The coldest month is December with an average daytime temperature of 8 °C in the past few years.

Which month is the wettest in Jefferson County?

Chance of precipitation is the highest in February with a probability of around 7.7 %.

Which month is the driest in Jefferson County?

The least rainfall and snow can be expected in July. The probability is about 0.4 %.