Climate and monthly weather forecastMarion, IA
Climate and monthly weather forecast
The climate of Marion
Nestled in the heart of the USA is the city of Marion, Iowa. Predominantly characterized by the Köppen climate classification as Dfa - a humid continental zone with no dry season and hot summers. This marks the climate of Marion with prominent seasonal variations throughout the year and a moderately high humidity, prevalent almost every month with slight fluctuations. The temperature, humidity, and pressure create a particular weather pattern distinct to Marion, making it a city of contrasts when it comes to weather conditions.Throughout the year, temperatures fluctuate between minimum of 14.2°F (-9.9°C) in winter to maximum of 80.2°F (26.8°C) in summer. Humidity varies, extending from a low of 73% to a high of 85%. Substantial variations in pressure and cloud cover percentage are also prevalent throughout the year. Rainfall ranges from a light 1.34" (34mm) to a heavier 5" (127mm), with May being the wettest month. During the colder months, snowfall is also a common occurrence, with December to February being the peak snowfall period.
Residents of Marion experience a decent amount of sunlight throughout the year. Sunshine hours peak at 9.8 hours in the middle of the year. Saliently, strong winds are quite common, reaching a maximum speed of 16.8mph (27km/h), adding another dynamic aspect to the climate of Marion.
The best time to visit Marion
For most visitors, the ideal time for a comfortable and pleasant visit to Marion falls between May and September. During these months, temperatures are usually toasty, extending from a pleasant 57.9°F (14.4°C) to a high of 80.2°F (26.8°C). Humidity is moderate, making outings comfortable yet refreshingly cool. Additionally, there is ample daylight, up to 15.2 hours at the peak of the summer season, and a high amount of sunshine per day.The worst time to visit Marion
Despite its classic charm, Marion can be a challenging destination during the winter months. From December to February, temperatures dive to a harsh low between 14.2°F (-9.9°C) to 33.1°F (0.6°C). Coupled with snowfall reaching a high of 5.79" (147mm) in December, outings might prove not only uncomfortable but also potentially risky. Limited sunlight and high winds only exacerbate the situation, making these winter months a difficult time for travel.Spring weather in Marion
Spring in Marion, extending from March to May, sees gradual warming of temperatures, with lows rising from 30.7°F (-0.7°C) to highs of 68.9°F (20.5°C). Rainfall increases gradually throughout the spring, making way for the summer showers. It is also noteworthy that daylight increases progressively from 12 to 14.6 hours. Overall, spring presents a delightful balance of moderate temperatures, increasing rainfall, and steady wind speeds.Summer weather in Marion
Summer, stretching from June to August, is the warmest time in Marion, with temperatures reaching a soaring high of 80.2°F (26.8°C). Humidity hits a peak of 84%, making the air thick and sweltering. Surprisingly, this is also the season with maximum daylight reaching a high of 15.2 hours. There is a drastic drop in rainfall from 5" (127mm) in May to 3.31" (84mm) in July, giving a bit of a breather from the otherwise drenching showers.Autumn weather in Marion
Autumn months, from September to November, mark a noticeable decline in temperatures in Marion, dipping from 74.1°F (23.4°C) to a lower 45.3°F (7.4°C). Rainfall decreases gradually throughout the season, and the city experiences less daylight, making the weather cooler and the days shorter. The wind speeds, however, start picking up during this time, adding a crispness to the air.Winter weather in Marion
The winter in Marion, from December to February, gets harshly cold, with a plunge in temperatures between 33.1°F (0.6°C) to 14.2°F (-9.9°C). The city wears a white blanket, with December and January being the peak snowfall months. Despite the decrease in daylight hours and high winds whipping across the city, an occasional sunny day brings a shimmering charm to the snow-laden city.Weather in January
Begin the year with the chill of winter in Marion, Iowa where Covering the ground is snowfall totaling 5.79" (147mm). Residents adapt to the colder temperatures, layering clothing to stay warm and the city typically sees relatively high humidity adding to the discomfort. Weather in January »Weather in February
While February still carries the chill of winter in Marion, Iowa, there's a slight uptick in temperature. With high humidity and snowy weather only slightly less than the previous month, February remains a month for winter wear. Weather in February »Weather in March
As spring approaches, March sees an improvement in the weather at Marion, touching a high of 45.5°F (7.5°C). There's quite a significant reduction in snowfall, marking the transition from winter into spring. The skies also start to clear up, allowing for more daylight hours and consequently, a lot more direct sunlight. Weather in March »Weather in April
With temperatures continually on the rise, April symbolizes the full arrival of spring in Marion, Iowa. There's a significant uptick in rainfall, with April showers becoming a common occurrence. The disappearance of snow is fully marked as the landscape takes on a fresh, rejuvenated look. Weather in April »Weather in May
May ushers in peak spring season in Marion, and the temperature rises to a comfortable 68.9°F (20.5°C). The increased rainfall contributes to the lush greenery typical of the month, setting a picturesque natural backdrop. The lengthened daylight hours extend the possibilities for outdoor activities into the late evening. Weather in May »Weather in June
June in Marion, Iowa brings the onset of summer, boasting the highest concentration of daylight hours for the year. Dry days are prevalent, and high temperatures become the norm. An increase in wind speed provides some relief from the hot and humid conditions. Weather in June »Weather in July
July heat peaks in Marion with an average high temperature touching 80.2°F (26.8°C). Summery weather dominates the city, with people opting for cool clothing and hydrating drinks with typical summer accessories like sunglasses and sun hats being commonplace. Weather in July »Weather in August
August continues the heat wave in Marion, Iowa, but temperatures begin to plateau. There is a noticeable drop in rainfall as summer reaches its zenith. Outdoor activities are still a favorite among residents, with plenty of daylight hours available for exploration or relaxation. Weather in August »Weather in September
September brings a welcome change to the torrid summer heat in Marion. As fall commences, a gradual decrease in daylight hours signifies the impending cold weather. September is largely favorable weather-wise, with predominantly dry conditions and comfortable temperatures. Weather in September »Weather in October
October in Marion, Iowa witnesses a more evident dip in temperature, signaling the strong onset of fall. Dry days with minimal rainfall make for beautiful outdoor moments. The city scenery transforms into a fall foliage spectacle, with leaves turning to vibrant hues of red, yellow, and orange. Weather in October »Weather in November
November weather in Marion brings colder conditions, closely resembling the chill of winter. The combination of high humidity and wind speed enhances the cold, marking the end of fall. Cloudy skies become a familiar sight once more, reminding residents of the inevitable approach of winter. Weather in November »Weather in December
Closing the year is the cold December weather in Marion. Winter conditions become fully pronounced in the city with 3.11" (79mm) of snow covering the ground. Iowans wrap up warmly, battling the freezing temperatures and reduced daylight hours. Weather in December »Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
Average temperature
Marion, IA
The warmest month (with the highest average high temperature) is July (80.2°F).
The month with the lowest average high temperature is January (26.2°F).
The month with the highest average low temperature is July (64.4°F).
The coldest month (with the lowest average low temperature) is January (14.2°F).
Average pressure
Marion, IA
- Average pressure in January:
30.14"Hg - Average pressure in February:
30.12"Hg - Average pressure in March:
30.08"Hg - Average pressure in April:
29.93"Hg - Average pressure in May:
29.94"Hg - Average pressure in June:
29.9"Hg
- Average pressure in July:
29.96"Hg - Average pressure in August:
29.97"Hg - Average pressure in September:
30.02"Hg - Average pressure in October:
30"Hg - Average pressure in November:
30.09"Hg - Average pressure in December:
30.11"Hg
The month with the highest atmospheric pressure is January (30.14"Hg).
The month with the lowest atmospheric pressure is June (29.9"Hg).
Average wind speed
Marion, IA
- Average wind speed in January:
10.6mph - Average wind speed in February:
10.6mph - Average wind speed in March:
10.5mph - Average wind speed in April:
10.8mph - Average wind speed in May:
9.1mph - Average wind speed in June:
7.9mph
The windiest month (with the highest average wind speed) is April (10.8mph).
The calmest months (with the lowest average wind speed) are July and August (7mph).
Average humidity
Marion, IA
The month with the highest relative humidity is January (85%).
The month with the lowest relative humidity is October (73%).
Average rainfall
Marion, IA
- Average rainfall in January:
1.34" - Average rainfall in February:
1.38" - Average rainfall in March:
2.05" - Average rainfall in April:
3.43" - Average rainfall in May:
5" - Average rainfall in June:
4.37"
- Average rainfall in July:
3.31" - Average rainfall in August:
2.09" - Average rainfall in September:
2.72" - Average rainfall in October:
2.56" - Average rainfall in November:
1.77" - Average rainfall in December:
1.57"
The wettest month (with the highest rainfall) is May (5").
The driest month (with the least rainfall) is January (1.34").
Average rainfall days
Marion, IA
- Average rainfall days in January:
5.2 days - Average rainfall days in February:
5.2 days - Average rainfall days in March:
12.1 days - Average rainfall days in April:
15.9 days - Average rainfall days in May:
19 days - Average rainfall days in June:
18.8 days
- Average rainfall days in July:
17.6 days - Average rainfall days in August:
14 days - Average rainfall days in September:
12 days - Average rainfall days in October:
12.2 days - Average rainfall days in November:
9.1 days - Average rainfall days in December:
6.8 days
The month with the highest number of rainy days is May (19 days).
The months with the least rainy days are January and February (5.2 days).
Average snowfall
Marion, IA
The month with the highest snowfall is January (5.79").
The months with the least snowfall are May, June, July, August and September (0").
Average snowfall days
Marion, IA
- Average snowfall days in January:
12.7 days - Average snowfall days in February:
10.3 days - Average snowfall days in March:
6.1 days - Average snowfall days in April:
1.4 days - Average snowfall days in May:
0.1 days - Average snowfall days in June:
0 days
- Average snowfall days in July:
0 days - Average snowfall days in August:
0 days - Average snowfall days in September:
0 days - Average snowfall days in October:
0.7 days - Average snowfall days in November:
3.2 days - Average snowfall days in December:
9.5 days
The month with the highest number of snowfall days is January (12.7 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight / Average sunshine
Marion, IA
- Average daylight in January:
9h and 30min - Average daylight in February:
10h and 36min - Average daylight in March:
12h and 0min - Average daylight in April:
13h and 24min - Average daylight in May:
14h and 36min - Average daylight in June:
15h and 12min
- Average daylight in July:
14h and 54min - Average daylight in August:
13h and 48min - Average daylight in September:
12h and 30min - Average daylight in October:
11h and 6min - Average daylight in November:
9h and 48min - Average daylight in December:
9h and 12min
The month with the longest days is June (Average daylight: 15h and 12min).
The month with the shortest days is December (Average daylight: 9h and 12min).
- Average sunshine in January:
4h and 0min - Average sunshine in February:
4h and 6min - Average sunshine in March:
6h and 18min - Average sunshine in April:
7h and 30min - Average sunshine in May:
8h and 24min - Average sunshine in June:
9h and 30min
- Average sunshine in July:
9h and 48min - Average sunshine in August:
9h and 48min - Average sunshine in September:
9h and 12min - Average sunshine in October:
5h and 24min - Average sunshine in November:
5h and 18min - Average sunshine in December:
4h and 18min
The months with the most sunshine are July and August (Average sunshine: 9h and 48min).
The month with the least sunshine is January (Average sunshine: 4h and 0min).
Average sunshine days
Marion, IA
- Average sunshine days in January:
15.5 days - Average sunshine days in February:
14 days - Average sunshine days in March:
13.9 days - Average sunshine days in April:
11.2 days - Average sunshine days in May:
9.2 days - Average sunshine days in June:
8.1 days
- Average sunshine days in July:
9.6 days - Average sunshine days in August:
13.8 days - Average sunshine days in September:
15.9 days - Average sunshine days in October:
16.9 days - Average sunshine days in November:
17 days - Average sunshine days in December:
16.8 days
The month with the most sunshine days is November (17 days).
The month with the least sunshine days is June (8.1 days).
Average UV index
Marion, IA
The month with the highest UV index is July (UV index 6).
The month with the lowest UV index is December (UV index 1).
Average cloud cover
Marion, IA
The month with the most cloud cover is January (Cloud cover 58).
The months with the least cloud cover are August and September (Cloud cover 31).
Average visibility
Marion, IA
The months with the highest visibility are January, February, March, April, May, June, August, September, October, November and December (6mi).
The month with the lowest visibility is July (5mi).





