Climate - Des Moines (Iowa)

The climate of Des Moines, the most populous city and capital of Iowa, is continental, with very cold winters and hot summers, with quite frequent thunderstorms.
The city is located in the Midwest of the United States, at an altitude of 250 meters (820 feet).
The climate is characterized by clashes of air masses of different origins, which give rise to sudden changes in temperature, thunderstorms (in spring and summer), sometimes accompanied by hail, and intense cold waves in winter.
The average temperature of the coldest month (January) is of -5.4 °C (22.4 °F), that of the warmest month (July) is of 24.4 °C (76 °F). Here are the average temperatures.

Precipitation amounts to 930 millimeters (36.6 inches) per year: so, it is at an intermediate level. It ranges from 25 mm (1 in) in the driest month (January) to 135 mm (5.3 in) in the wettest ones (May, June). Here is the average precipitation.

Winter, from late November to early March, is very cold.
Snowfalls are frequent, although generally they are not very abundant, since winter is the driest season of the year. On average, 93 centimeters (36.5 inches) of snow fall per year. It usually snows from October through April. The heaviest snowfall in one day occurred on January 26, 1996, when 35 cm (13.7 in) of snow fell.
On average, there are 128 days on which the minimum temperature is equal to or below freezing, and that usually happens from October through April. Furthermore, there are 46 icing days (that is, on which the air temperature does not go above freezing), and that usually happens from November through March.
Cold waves are intense, in fact, the temperature usually drops to -25 °C (-13 °F) on the coldest nights of the year. The record cold, -32 °C (-25.5 °F), occurred in February 1996.
However, there may be short periods when the temperature exceeds 10/12 °C (50/54 °F), and sometimes reaches as high as 20 °C (68 °F), even in the middle of winter.

Summer, from June to August, is hot and sunny, although thunderstorms can break out in the afternoon.
On average, there are 22 days with a maximum temperature equal to or above 32 °C (90 °F), and that usually happens from May through September.
Typically, the temperature reaches 37/38 °C (100/102 °F) on the hottest days of the year, although the record is 42 °C (108 °F), recorded in August 1983. In July 2012, the average maximum was 36.6 °C (97.9 °F).

Spring and autumn, from mid-March to May and from September to mid-November, are contrasted seasons, with fairly frequent rains and sudden changes in temperature. However, there are also stable and pleasant periods.
Des Moines is located in the area where tornadoes can form, which are most likely in spring, but can occasionally occur in autumn as well.



On average, there are around 2,690 sunshine hours per year. Thus, the sun shines for a good number of hours. Here are the average sunshine hours per day.

Best Time

The best time to visit Des Moines is early autumn, from September to early October. You can also choose spring, in particular the month of May, which however is a more unstable period.

Des Moines - Weather by month

Based on the period 1991-2020

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In January, the coldest month of the year, the weather in Des Moines is usually freezing cold. The average temperature is of -5.4 °C (22 °F), with a minimum of -10.1 °C (13.8 °F) and a maximum of -0.6 °C (30.9 °F).
On the coldest nights of the month, the temperature usually drops to around -22 °C (-8 °F). However, it dropped to -29.4 °C (-20.9 °F) in January 1996.
On the warmest days of the month, the temperature usually reaches around 12 °C (53.5 °F). However, it reached 19.4 °C (66.9 °F) in January 2003.
Precipitation amounts to 25 mm (1 in), distributed over 8 days.
The day lasts on average 9 hours and 35 minutes.
There are on average 5 hours of sunshine per day. So, the sun shines 53% of the time.
The average humidity is 73%. Hence, the air is normally humid.
The average wind speed is 17 kph (10 mph).

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In February, the weather in Des Moines is usually very cold. The average temperature is of -2.9 °C (27 °F), with a minimum of -7.8 °C (18 °F) and a maximum of 2.1 °C (35.7 °F).
On the coldest nights of the month, the temperature usually drops to around -19.5 °C (-3 °F). However, it dropped to -32.2 °C (-26 °F) in February 1996.
On the warmest days of the month, the temperature usually reaches around 15 °C (59 °F). However, it reached 23.9 °C (75 °F) in February 2017.
Precipitation amounts to 35 mm (1.4 in), distributed over 8 days.
The day lasts on average 10 hours and 40 minutes.
There are on average 6 hours of sunshine per day. So, the sun shines 55% of the time.
The average humidity is 71%. Hence, the air is normally humid.
The average wind speed is 16 kph (10 mph).

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In March, the weather in Des Moines is usually quite cold. The average temperature is of 4.1 °C (39 °F), with a minimum of -1.3 °C (29.6 °F) and a maximum of 9.6 °C (49.2 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around -12.5 °C (9.5 °F). However, it dropped to -23 °C (-9.4 °F) in March 1998.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 23.5 °C (74.5 °F). However, it reached 30.6 °C (87.1 °F) in March 1991.
Precipitation amounts to 55 mm (2.2 in), distributed over 10 days.
The day lasts on average 12 hours and 0 minutes.
There are on average 6.5 hours of sunshine per day. So, the sun shines 55% of the time.
The average humidity is 65%.
The average wind speed is 17 kph (11 mph).

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In April, the weather in Des Moines is usually mild. The average temperature is of 10.7 °C (51 °F), with a minimum of 4.8 °C (40.6 °F) and a maximum of 16.7 °C (62 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around -4 °C (24.5 °F). However, it dropped to -10 °C (14 °F) in April 2018.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 29 °C (84 °F). However, it reached 32.2 °C (90 °F) in April 2011.
Precipitation amounts to 100 mm (3.9 in), distributed over 12 days.
The day lasts on average 13 hours and 25 minutes.
There are on average 7.5 hours of sunshine per day. So, the sun shines 55% of the time.
The average humidity is 60%.
The average wind speed is 18 kph (11 mph).

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In May, the weather in Des Moines is usually very mild. The average temperature is of 16.9 °C (62 °F), with a minimum of 11.3 °C (52.3 °F) and a maximum of 22.4 °C (72.4 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 3 °C (37.5 °F). However, it dropped to -1.1 °C (30 °F) in May 2005.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 31.5 °C (89 °F). However, it reached 37.2 °C (99 °F) in May 2018.
Precipitation amounts to 135 mm (5.3 in), distributed over 13 days.
The day lasts on average 14 hours and 35 minutes. So the days are long.
There are on average 9 hours of sunshine per day. So, the sun shines 61% of the time.
The average humidity is 64%.
The average wind speed is 16 kph (10 mph).

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In June, the weather in Des Moines is usually warm. The average temperature is of 22.3 °C (72 °F), with a minimum of 16.9 °C (62.4 °F) and a maximum of 27.7 °C (81.9 °F).
On the coldest nights, which normally occur at the beginning of the month, the temperature usually drops to around 10 °C (50 °F). However, it dropped to 5.6 °C (42.1 °F) in June 2001.
On the warmest days, which normally occur at the end of the month, the temperature usually reaches around 34 °C (93 °F). However, it reached 38.3 °C (100.9 °F) in June 2012.
Precipitation amounts to 135 mm (5.3 in), distributed over 12 days.
The day lasts on average 15 hours and 5 minutes. So the days are long. June 21, the summer solstice, is the longest day of the year in the Northern Hemisphere.
There are on average 10.5 hours of sunshine per day. So, the sun shines 69% of the time.
The average humidity is 66%.
The average wind speed is 14 kph (9 mph).

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In July, the warmest month of the year, the weather in Des Moines is usually warm to hot. The average temperature is of 24.4 °C (76 °F), with a minimum of 19.1 °C (66.4 °F) and a maximum of 29.8 °C (85.6 °F).
On the coldest nights of the month, the temperature usually drops to around 14 °C (57 °F). However, it dropped to 10 °C (50 °F) in July 1995.
On the warmest days of the month, the temperature usually reaches around 35.5 °C (96.5 °F). However, it reached 41.1 °C (106 °F) in July 2012.
Precipitation amounts to 95 mm (3.7 in), distributed over 10 days.
The day lasts on average 14 hours and 50 minutes. So the days are long.
There are on average 11 hours of sunshine per day. So, the sun shines 73% of the time.
The average humidity is 69%.
The average wind speed is 13 kph (8 mph).

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In August, the weather in Des Moines is usually warm to hot and muggy. The average temperature is of 23.3 °C (74 °F), with a minimum of 17.9 °C (64.2 °F) and a maximum of 28.7 °C (83.6 °F).
On the coldest nights of the month, the temperature usually drops to around 12.5 °C (55 °F). However, it dropped to 7.8 °C (46 °F) in August 1992.
On the warmest days of the month, the temperature usually reaches around 34.5 °C (94.5 °F). However, it reached 40 °C (104 °F) in August 2013.
Precipitation amounts to 105 mm (4.1 in), distributed over 9 days.
The day lasts on average 13 hours and 50 minutes.
There are on average 9.5 hours of sunshine per day. So, the sun shines 69% of the time.
The average humidity is 70%. Hence, the air is normally humid.
The average wind speed is 12 kph (8 mph).

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In September, the weather in Des Moines is usually warm. The average temperature is of 19.0 °C (66 °F), with a minimum of 13 °C (55.4 °F) and a maximum of 24.9 °C (76.9 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around 4.5 °C (40.5 °F). However, it dropped to -0.6 °C (30.9 °F) in September 1995.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 33 °C (91 °F). However, it reached 38.3 °C (100.9 °F) in September 2013.
Precipitation amounts to 80 mm (3.1 in), distributed over 8 days.
The day lasts on average 12 hours and 25 minutes.
There are on average 8 hours of sunshine per day. So, the sun shines 64% of the time.
The average humidity is 67%.
The average wind speed is 14 kph (8 mph).

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In October, the weather in Des Moines is usually mild. The average temperature is of 11.8 °C (53 °F), with a minimum of 6.1 °C (42.9 °F) and a maximum of 17.4 °C (63.4 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around -3 °C (27 °F). However, it dropped to -8 °C (17.6 °F) in October 1997.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 29 °C (84 °F). However, it reached 33 °C (91.4 °F) in October 1997.
Precipitation amounts to 70 mm (2.8 in), distributed over 9 days.
The day lasts on average 11 hours and 0 minutes.
There are on average 7 hours of sunshine per day. So, the sun shines 62% of the time.
The average humidity is 65%.
The average wind speed is 16 kph (10 mph).

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In November, the weather in Des Moines is usually quite cold. The average temperature is of 4.0 °C (39 °F), with a minimum of -1 °C (30.2 °F) and a maximum of 9.1 °C (48.3 °F).
On the coldest nights, which normally occur at the end of the month, the temperature usually drops to around -10.5 °C (13 °F). However, it dropped to -20 °C (-4 °F) in November 1991.
On the warmest days, which normally occur at the beginning of the month, the temperature usually reaches around 21 °C (70 °F). However, it reached 27.2 °C (81 °F) in November 1999.
Precipitation amounts to 50 mm (2 in), distributed over 8 days.
The day lasts on average 9 hours and 50 minutes.
There are on average 4.5 hours of sunshine per day. So, the sun shines 47% of the time.
The average humidity is 68%.
The average wind speed is 17 kph (10 mph).

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In December, the weather in Des Moines is usually very cold. The average temperature is of -2.4 °C (28 °F), with a minimum of -6.9 °C (19.5 °F) and a maximum of 2.2 °C (35.9 °F).
On the coldest nights of the month, the temperature usually drops to around -18 °C (-0.5 °F). However, it dropped to -25.6 °C (-14.1 °F) in December 2013.
On the warmest days of the month, the temperature usually reaches around 14.5 °C (57.5 °F). However, it reached 20.6 °C (69.1 °F) in December 2012.
Precipitation amounts to 40 mm (1.6 in), distributed over 8 days.
The day lasts on average 9 hours and 10 minutes. December 21, the winter solstice, is the shortest day of the year in the Northern Hemisphere.
There are on average 4 hours of sunshine per day. So, the sun shines 45% of the time.
The average humidity is 74%. Hence, the air is normally humid.
The average wind speed is 16 kph (10 mph).