Iowa climate

World Climates covers 3 places in Iowa. By annual mean temperature, the warmest is Davenport (10 °C51 °F) and the coolest is Cedar Rapids (9 °C49 °F). The wettest is Davenport with 924 mm36 in of precipitation per year, the driest Des Moines with 884 mm35 in.

The most common climate types (Köppen classification computed from these averages) are hot-summer humid continental (Dfa, 3 places).

The highest monthly average high is in Des Moines (31 °C87 °F in July); the lowest monthly average low is in Cedar Rapids (−11 °C12 °F in January).

Across the places in Iowa, the months that most often rank as the most comfortable are May, August and September (1, 1 and 3 of 3 places respectively).

Temperature and rainfall across Iowa

Annual mean temperatures in Iowa range from 9 °C49 °F to 10 °C51 °F. The typical place (the median of all 3) has a year average of 10 °C51 °F. Annual precipitation ranges from 884 mm35 in to 924 mm36 in. The median place receives about 922 mm36 in in an average year.

In 3 places of 3, the coldest month has an average low below 0 °C (32 °F). In 1 place, the warmest month has an average high above 30 °C (86 °F). No place here gets less than 250 mm (10 in) of precipitation a year. None gets more than 2,000 mm (79 in) a year.

Averaged over all 3 places, July is the warmest month, with a mean of 24 °C76 °F. January is the coldest, with −6 °C22 °F. The wettest month on average is June (132 mm5.2 in). The driest is January (28 mm1.1 in). Single places can differ a lot from this average, so check the page of each city.

The table below lists the places sorted by population. The largest ones covered here are Des Moines, Cedar Rapids and Davenport. Each city page has a chart and a table for every month. It also shows the best time to visit and what to pack. The figures are 25-year averages for 2001–2025 from NASA POWER. They describe grid cells of roughly 50–70 km, not single weather stations.

Climate of each place in Iowa

Des Moines has a hot-summer humid continental climate (Köppen Dfa). Its year average is 10 °C51 °F. The warmest month is July, with an average high of 31 °C87 °F. The coldest is January, with an average low of −10 °C14 °F. About 884 mm35 in of precipitation falls in a year. June is the wettest month and January the driest. By our comfort score, the best months to visit are September.

Cedar Rapids has a hot-summer humid continental climate (Köppen Dfa). Its year average is 9 °C49 °F. The warmest month is July, with an average high of 29 °C84 °F. The coldest is January, with an average low of −11 °C12 °F. About 922 mm36 in of precipitation falls in a year. June is the wettest month and January the driest. By our comfort score, the best months to visit are May and August and September.

Davenport has a hot-summer humid continental climate (Köppen Dfa). Its year average is 10 °C51 °F. The warmest month is July, with an average high of 30 °C86 °F. The coldest is January, with an average low of −10 °C14 °F. About 924 mm36 in of precipitation falls in a year. June is the wettest month and January the driest. By our comfort score, the best months to visit are September.

Frequently asked questions

Which is the warmest place in Iowa?

By annual mean temperature, the warmest place in Iowa is Davenport at 10 °C51 °F. The coolest is Cedar Rapids at 9 °C49 °F.

Where does it rain the most in Iowa?

Davenport gets the most precipitation, 924 mm36 in in an average year. The driest place is Des Moines with 884 mm35 in.

How many places in Iowa does this site cover?

World Climates has climate data for 3 places in Iowa. Each one has a page with monthly averages for temperature, rainfall, humidity and daylight.

When is the best time to visit Iowa?

It depends on the place. Across Iowa, the months that most often rank as the most comfortable are May, August and September. Check the page of each city for its own best months.