Marion weather by month

Check out Marion weather averages by month. Compare detailed monthly climate statistics including temperature, rainfall and sunshine figures.

Temperature
Rainfall
Sunshine & UV index

Temperature in Marion (°F)

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Max temperature (daytime)	39	45	57	68	77	86	90	88	81	70	57	45
Min temperature (night-time)	21	25	36	46	54	63	66	64	57	45	36	27
Heat & Humidity	0	0	0	0	0	M	H	H	L	0	0	0

Note: 0 = None, L = Low, M = Moderate, H = High, VH = Very high, E = Extreme

Sunshine & UV index in Marion

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Daily hours of sunshine	5	5	6	8	9	10	10	10	8	7	5	4
Daily hours of daylight	10	11	12	13	14	15	14	14	12	11	10	10
UV Index (Maximum)	2	3	5	7	8	9	10	9	7	5	3	2

Rainfall in Marion

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Number of days with some rain	9	9	12	11	10	9	9	8	8	8	10	10
Average monthly rainfall (inches)	2.8	3.1	4.9	4.3	4.9	3.8	3.9	3.5	3.2	3.0	4.1	4.0

More about Marion

Marion by month

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec

Recommended for Illinois

TUI: Top deals & discounts on 2026/2027 holidays

Sale

Explore latest special offers & online deals from TUI
Free child places & £0 deposits with direct debit available
Book summer & winter sun holidays in 2026/2027

Go to TUI deal >>

View all TUI offers

TUI deal finder

Destination

The climate guide for Illinois (Marion) shows long term monthly weather averages processed from data supplied by CRU (University of East Anglia), the Met Office & the Netherlands Meteorological Institute. Find out more about our data sources.

What's the climate like in Marion?

Marion has a cold climate with hot summers and some rainfall in all months.

Marion weather in January

Expect daytime maximum temperatures of 39°F in Marion, Illinois in January based on long-term weather averages. There are 5 hours of sunshine per day on average with typically 2.8 inches of rainfall in the month, which might fall as snow.

39
39°F max day temperature
5
5 hours of sunshine per day
9
9 days with some rainfall
21
21°F min night temperature
10
10 hours of daylight per day
0
No heat & humidity
2.8
2.8 inches of monthly rainfall
2
2 (Low) UV index

Back to months

Marion weather in February

Expect daytime maximum temperatures of 45°F in Marion, Illinois in February based on long-term weather averages. There are 5 hours of sunshine per day on average with typically 3.1 inches of rainfall in the month.

45
45°F max day temperature
5
5 hours of sunshine per day
9
9 days with some rainfall
25
25°F min night temperature
11
11 hours of daylight per day
0
No heat & humidity
3.1
3.1 inches of monthly rainfall
3
3 (Moderate) UV index

Back to months

Marion weather in March

Expect daytime maximum temperatures of 57°F in Marion, Illinois in March based on long-term weather averages. There are 6 hours of sunshine per day on average with 12 days with some rainfall and typically 4.9 inches of rainfall in the month.

57
57°F max day temperature
6
6 hours of sunshine per day
12
12 days with some rainfall
36
36°F min night temperature
12
12 hours of daylight per day
0
No heat & humidity
4.9
4.9 inches of monthly rainfall
5
5 (Moderate) UV index

Back to months

Marion weather in April

Expect daytime maximum temperatures of 68°F in Marion, Illinois in April based on long-term weather averages. There are 8 hours of sunshine per day on average with 11 days with some rainfall and typically 4.3 inches of rainfall in the month.

68
68°F max day temperature
8
8 hours of sunshine per day
11
11 days with some rainfall
46
46°F min night temperature
13
13 hours of daylight per day
0
No heat & humidity
4.3
4.3 inches of monthly rainfall
7
7 (High) UV index

Back to months

Marion weather in May

Expect daytime maximum temperatures of 77°F in Marion, Illinois in May based on long-term weather averages. There are 9 hours of sunshine per day on average with 10 days with some rainfall and typically 4.9 inches of rainfall in the month.

77
77°F max day temperature
9
9 hours of sunshine per day
10
10 days with some rainfall
54
54°F min night temperature
14
14 hours of daylight per day
0
No heat & humidity
4.9
4.9 inches of monthly rainfall
8
8 (Very High) UV index

Back to months

Marion weather in June

Expect daytime maximum temperatures of 86°F in Marion, Illinois in June based on long-term weather averages. There are 10 hours of sunshine per day on average with typically 3.8 inches of rainfall in the month.

86
86°F max day temperature
10
10 hours of sunshine per day
9
9 days with some rainfall
63
63°F min night temperature
15
15 hours of daylight per day
M
Moderate heat & humidity
3.8
3.8 inches of monthly rainfall
9
9 (Very High) UV index

Back to months

Marion weather in July

Expect daytime maximum temperatures of 90°F in Marion, Illinois in July and high heat and humidity based on long-term weather averages. There are 10 hours of sunshine per day on average with typically 3.9 inches of rainfall in the month.

90
90°F max day temperature
10
10 hours of sunshine per day
9
9 days with some rainfall
66
66°F min night temperature
14
14 hours of daylight per day
H
High heat & humidity
3.9
3.9 inches of monthly rainfall
10
10 (Very High) UV index

Back to months

Marion weather in August

Expect daytime maximum temperatures of 88°F in Marion, Illinois in August and high heat and humidity based on long-term weather averages. There are 10 hours of sunshine per day on average with typically 3.5 inches of rainfall in the month.

88
88°F max day temperature
10
10 hours of sunshine per day
8
8 days with some rainfall
64
64°F min night temperature
14
14 hours of daylight per day
H
High heat & humidity
3.5
3.5 inches of monthly rainfall
9
9 (Very High) UV index

Back to months

Marion weather in September

Expect daytime maximum temperatures of 81°F in Marion, Illinois in September based on long-term weather averages. There are 8 hours of sunshine per day on average with typically 3.2 inches of rainfall in the month.

81
81°F max day temperature
8
8 hours of sunshine per day
8
8 days with some rainfall
57
57°F min night temperature
12
12 hours of daylight per day
L
Low heat & humidity
3.2
3.2 inches of monthly rainfall
7
7 (High) UV index

Back to months

Marion weather in October

Expect daytime maximum temperatures of 70°F in Marion, Illinois in October based on long-term weather averages. There are 7 hours of sunshine per day on average with typically 3.0 inches of rainfall in the month.

70
70°F max day temperature
7
7 hours of sunshine per day
8
8 days with some rainfall
45
45°F min night temperature
11
11 hours of daylight per day
0
No heat & humidity
3.0
3.0 inches of monthly rainfall
5
5 (Moderate) UV index

Back to months

Marion weather in November

Expect daytime maximum temperatures of 57°F in Marion, Illinois in November based on long-term weather averages. There are 5 hours of sunshine per day on average with 10 days with some rainfall and typically 4.1 inches of rainfall in the month.

57
57°F max day temperature
5
5 hours of sunshine per day
10
10 days with some rainfall
36
36°F min night temperature
10
10 hours of daylight per day
0
No heat & humidity
4.1
4.1 inches of monthly rainfall
3
3 (Moderate) UV index

Back to months

Marion weather in December

Expect daytime maximum temperatures of 45°F in Marion, Illinois in December based on long-term weather averages. There are 4 hours of sunshine per day on average with 10 days with some rainfall and typically 4.0 inches of rainfall in the month.