Climate and monthly weather forecastMarshalltown, IA
Climate and monthly weather forecast
The climate of Marshalltown
Falling under the Köppen climate classification of Dfa, Marshalltown, situated in the heart of Iowa in the United States, experiences a humid continental climate. This climate type is characterized by no dry season, with hot summers. Observing the monthly climate statistics, it is evident that the weather varies substantially throughout the year, with a marked difference in temperature and precipitation patterns.Temperature in Marshalltown ranges from a frigid 12.7°F (-10.7°C) in the colder months to a warm 80.8°F (27.1°C) in peak summer. Notably, July holds the record for the highest average temperatures, while January is typically the coldest month. The town also sees a significant shift in rainfall over the year, from a minimal 0.43" (11mm) in January to a high of 2.56" (65mm) in June. This suggests that certain periods may see heavier downpours than others.
The relative humidity typically hovers around 82%, indicating a generally humid environment. Wind speed in Marshalltown is moderate, averaging between 7.1mph (11.4km/h) to 10.8mph (17.4km/h) throughout the year. The sunniest period in Marshalltown falls between May and August, with an average of 9.5 hours of sunshine a day, while the cloudiest periods tend to be in the cooler months. The visibility in Marshalltown primarily maintains around 6 miles throughout the year, dipping slightly to 5 miles in mid-summer.
The Best Time to Visit Marshalltown
Tourists planning a trip to Marshalltown should consider visiting between March and May or from September to October. During these transitional seasons, temperatures are comfortable, averaging around 57.7°F (14.3°C) to 68.7°F (20.4°C). Rainfall is moderate, offering a balance between occasional showers and dry spells. These periods also offer longer daylight hours, resulting in more time to explore local attractions. The UV index during spring and fall is moderate, providing a more comfortable outdoor experience.The Worst Time to Visit Marshalltown
Winter, typically from December to February, may not be the ideal time to visit Marshalltown, unless visitors are prepared for harsh weather conditions. During this period, the temperatures plunge and hover between 12.7°F (-10.7°C) to 29.8°F (-1.2°C), with snowfall ranging from 0.79" (20mm) to 1.93" (49mm). Coupled with a high relative humidity of up to 86%, this makes for freezing and potentially uncomfortable conditions. The shorter days also mean less daylight for sightseeing and activities.Spring Weather in Marshalltown
Spring is a delightful season in Marshalltown. This period, from March till May, is characterized by a gradual increase in temperature from 44.8°F (7.1°C) to 68.7°F (20.4°C). Combined with the increase in daylight hours, moving from 12 hours in March to 14.6 hours in May, it marks a transition from the harshness of winter to more pleasant conditions. Interestingly, rainfall tends to increase during this time, registering an average rainfall of 1.93" (49mm) in April, the highest amount of spring precipitation.Summer Weather in Marshalltown
With temperatures that can soar up to 80.8°F (27.1°C), summer in Marshalltown, lasting from June to August, is hot and the daylight extends to a maximum of 15.2 hours in June. The air is substantially humid, with a relative humidity of 82-84%, and rainfall is relatively high, fluctuating between 1.54" (39mm) to 2.56" (65mm). Despite these conditions, the high UV index of 6 and maximum sunshine hours make it a busy season.Autumn Weather in Marshalltown
Marshalltown experiences a drop in temperature during the autumn months from September to November, with averages descending from 74.5°F (23.6°C) to 45.1°F (7.3°C). There is a welcome decrease in humidity and rainfall during this time, with the average rainfall ranging from 1.26" (32mm) to 0.79" (20mm). The average daylight hours also decrease, marking the transition towards the colder months. Despite this, the ample sunshine hours paired with fall foliage may entice outdoor enthusiasts.Winter Weather in Marshalltown
Winter in Marshalltown brings in harsh weather conditions along with a significant reduction in daylight hours, dropping to just 9.2 hours in December. Temperatures nose-dive, fluctuating between 21°F (-6.1°C) and 32°F (0°C), with snowfall seen in every month. Visibility in winter months remains fairly steady at 6 miles, still permitting outdoor activities for those ready to brave the cold.Weather in January
Marshalltown, Iowa starts the year with a typically cold winter month. In contrast to December, January sees higher snowfall with an average of 1.93" (49mm) covering the city in a beautiful winter cloak. Relative humidity hovers on the high side, adding to the feeling of a typical cold, frostbitten Iowa winter. Weather in January »Weather in February
The chill of January persists into February in Marshalltown, with cold temperatures remaining dominant. The decreasing snowfall from 1.93" (49mm) to 1.85" (47mm) brings a slight relief acknowledging the impending end of winter. Weather in February »Weather in March
The transition from winter to spring becomes evident in Marshalltown in March. A considerable rise in temperature, combined with a reduced snowfall of 0.79" (20mm), unfolds a different scene from the two previous months. Longer periods of daylight replace the short, cold winter days, sparking the growth of new life. Weather in March »Weather in April
In April, Marshalltown welcomes the heart of the spring season. Significant changes, like the increase in rainfall to 1.93" (49mm), make the weather predominantly wet, but not cold as in previous months. The atmosphere is mostly humid, sparking the burst of greenery around the city. Weather in April »Weather in May
May in Marshalltown brings a considerably warmer and damper atmosphere than April. The increase in precipitation peaks at 2.48" (63mm), contributing to higher levels of humidity in the city. As the city steps into late spring, the weather remains gentle, escorting residents into the early days of summer. Weather in May »Weather in June
June ushers in the summer season in Marshalltown, characterized by longer days and warmer temperatures. A unique characteristic of June is max UV index of 6, indicating strong sunshine. The increase in sunshine hours is enjoyed by everyone, resulting in exciting outdoor activities. Weather in June »Weather in July
July in Marshalltown is the epitome of the summer season. With temperatures peaking at 80.8°F (27.1°C), the weather is dominantly sunny, hot, and relatively dry. July appears to present a stark contrast to the chilly winter months, celebrating the heat and cheer of summer. Weather in July »Weather in August
August proceeds with the characteristic summer heat in Marshalltown, albeit slightly cooler than July. Another significant change is the slight decrease in sunlight, resulting in fewer daylight hours. The city feels comfortably warm, and residents can enjoy the lingering afternoons. Weather in August »Weather in September
Marshalltown in September sees the arrival of the fall season. The temperatures start to dip gradually, and the rainfall drops to 1.5" (38mm), indicating a shift in weather. The signs of autumn start to occur as the leaves begin to change and the weather starts to cool down. Weather in September »Weather in October
October greets Marshalltown with definitive signs of autumn. A consistent drop in temperatures from the previous months of September marks the beginning of cooler days. The trees adorn varied hues, creating a colorful and beautiful cityscape. Weather in October »Weather in November
November in Marshalltown brings the full swing of the fall season, lowering temperatures even further. A notable change from October is a decrease in rainfall to 0.79" (20mm), making it one of the less rainy months of the year. Weather in November »Weather in December
December in Marshalltown signifies the onset of winter with its colder temperatures and an increase in snowfall to 1.14" (29mm). The weather pattern clearly differs from November, signifying the prominence of winter. Shorter daylight hours and colder evenings begin to dominate the climate. Weather in December »Updated: Feb 12, 2024
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Published by: Weather U.S. | About Us
Data Sources | Weather Forecasting & Climate
Frequently asked questions
January, with its high-temperature average of 25.7°F (-3.5°C) and a low-temperature average of 12.7°F (-10.7°C), is the coldest month.
The most humid month in Marshalltown is January, with an average relative humidity of 86%.
The month with the least rainfall in Marshalltown, Iowa, is January, when the rain falls for 3.6 days and typically collects 0.43" (11mm) of precipitation.
In Marshalltown, during the entire year, the rain falls for 118.2 days and collects up to 16.18" (411mm) of precipitation.
January through May, October through December are months with snowfall in Marshalltown.
January is the month with the most snowfall in Marshalltown. Snow falls for 9.8 days and accumulates 1.93" (49mm) of snow.
In Marshalltown, during the entire year, snow falls for 34.6 days and aggregates up to 6.97" (177mm) of snow.
With an average of 3.9h of sunshine, January has the least sunshine of the year in Marshalltown.
The months with the lowest UV index in Marshalltown are January, February, October through December, with an average maximum UV index of 2.
On Sunday, March 10. 2024, at 2:00 am, Daylight Saving Time starts, and the time zone changes from CST to CDT. Daylight Saving Time ends Sunday, November 3. 2024, at 2:00 am, and the time zone reverts from CDT to CST.
June is the month with the most rainfall in Marshalltown, Iowa. Rain falls for 15.7 days and accumulates 2.56" (65mm) of precipitation.
June through September are months without snowfall.
The month with the longest days is June, with an average of 15h and 12min of daylight.
June and July, with an average maximum UV index of 6, are months with the highest UV index in Marshalltown.
Marshalltown's warmest weather arrives in July, when temperatures average a high of 80.8°F (27.1°C) and a low of 64.4°F (18°C).
The month with the most sunshine in Marshalltown, Iowa, is July, with an average of 10h of sunshine.
With an average relative humidity of 72%, October is the least humid month.
With an average of 9h and 12min of daylight, December has the shortest days of the year in Marshalltown, Iowa.
Average temperature
Marshalltown, IA
The warmest month (with the highest average high temperature) is July (80.8°F).
The month with the lowest average high temperature is January (25.7°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 (12.7°F).
Average pressure
Marshalltown, IA
- Average pressure in January:
30.15"Hg - Average pressure in February:
30.14"Hg - Average pressure in March:
30.08"Hg - Average pressure in April:
29.93"Hg - Average pressure in May:
29.93"Hg - Average pressure in June:
29.89"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 (30.15"Hg).
The month with the lowest atmospheric pressure is June (29.89"Hg).
Average wind speed
Marshalltown, IA
- Average wind speed in January:
10.7mph - Average wind speed in February:
10.7mph - Average wind speed in March:
10.6mph - Average wind speed in April:
10.8mph - Average wind speed in May:
9.3mph - Average wind speed in June:
8.2mph
- Average wind speed in July:
7.1mph - Average wind speed in August:
7.1mph - Average wind speed in September:
8.3mph - Average wind speed in October:
9.8mph - Average wind speed in November:
10.6mph - Average wind speed in December:
10.3mph
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 (7.1mph).
Average humidity
Marshalltown, IA
The month with the highest relative humidity is January (86%).
The month with the lowest relative humidity is October (72%).
Average rainfall
Marshalltown, IA
- Average rainfall in January:
0.43" - Average rainfall in February:
0.47" - Average rainfall in March:
0.91" - Average rainfall in April:
1.93" - Average rainfall in May:
2.48" - Average rainfall in June:
2.56"
- Average rainfall in July:
1.69" - Average rainfall in August:
1.54" - Average rainfall in September:
1.5" - Average rainfall in October:
1.26" - Average rainfall in November:
0.79" - Average rainfall in December:
0.63"
The wettest month (with the highest rainfall) is June (2.56").
The driest month (with the least rainfall) is January (0.43").
Average rainfall days
Marshalltown, IA
- Average rainfall days in January:
3.6 days - Average rainfall days in February:
2.8 days - Average rainfall days in March:
9.8 days - Average rainfall days in April:
13.2 days - Average rainfall days in May:
15.2 days - Average rainfall days in June:
15.7 days
- Average rainfall days in July:
14.6 days - Average rainfall days in August:
12.8 days - Average rainfall days in September:
10.6 days - Average rainfall days in October:
8.7 days - Average rainfall days in November:
6.4 days - Average rainfall days in December:
4.8 days
The month with the highest number of rainy days is June (15.7 days).
The month with the least rainy days is February (2.8 days).
Average snowfall
Marshalltown, IA
- Average snowfall in January:
1.93" - Average snowfall in February:
1.85" - Average snowfall in March:
0.79" - Average snowfall in April:
0.31" - Average snowfall in May:
0.04" - Average snowfall in June:
0"
The month with the highest snowfall is January (1.93").
The months with the least snowfall are June, July, August and September (0").
Average snowfall days
Marshalltown, IA
- Average snowfall days in January:
9.8 days - Average snowfall days in February:
7.8 days - Average snowfall days in March:
4.8 days - Average snowfall days in April:
1.3 days - Average snowfall days in May:
0.3 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:
0.6 days - Average snowfall days in November:
2.5 days - Average snowfall days in December:
7.5 days
The month with the highest number of snowfall days is January (9.8 days).
The months with the least snowfall days are June, July, August and September (0 days).
Average daylight / Average sunshine
Marshalltown, 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:
3h and 54min - Average sunshine in February:
4h and 18min - Average sunshine in March:
6h and 0min - Average sunshine in April:
7h and 42min - Average sunshine in May:
8h and 36min - Average sunshine in June:
9h and 30min
- Average sunshine in July:
10h and 0min - Average sunshine in August:
9h and 42min - Average sunshine in September:
9h and 18min - Average sunshine in October:
5h and 30min - Average sunshine in November:
5h and 24min - Average sunshine in December:
4h and 24min
The month with the most sunshine is July (Average sunshine: 10h and 0min).
The month with the least sunshine is January (Average sunshine: 3h and 54min).
Average sunshine days
Marshalltown, IA
- Average sunshine days in January:
19.8 days - Average sunshine days in February:
17.9 days - Average sunshine days in March:
16.9 days - Average sunshine days in April:
13.8 days - Average sunshine days in May:
12.9 days - Average sunshine days in June:
12.2 days
- Average sunshine days in July:
12.3 days - Average sunshine days in August:
15.2 days - Average sunshine days in September:
18 days - Average sunshine days in October:
20.5 days - Average sunshine days in November:
20.5 days - Average sunshine days in December:
20.6 days
The month with the most sunshine days is December (20.6 days).
The month with the least sunshine days is June (12.2 days).
Average UV index
Marshalltown, IA
The months with the highest UV index are June and July (UV index 6).
The months with the lowest UV index are January, February, October, November and December (UV index 2).
Average cloud cover
Marshalltown, IA
The month with the most cloud cover is January (Cloud cover 57).
The month with the least cloud cover is September (Cloud cover 30).
Average visibility
Marshalltown, IA
The months with the highest visibility are January, February, March, April, May, June, September, October, November and December (6mi).
The months with the lowest visibility are July and August (5mi).
