Des Moines, Iowa climate: Normal weather by month, frost dates and records
Des Moines's normal year runs from 14°F January nights to 86°F July afternoons, with 36.5 inches of precipitation and 37 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 10.5°C, January lows of −10°C, July highs of 30°C, 928 mm of precipitation a year.
- NOAA stationDes Moines International Airport
- Station IDUSW00014933
- Location41.53°N 93.65°W
- Elevation957 ft (292 m)
- From the center3 miles
- Population213,096
On October 23, the normal high in Des Moines is 60°F and the normal low 40°F, and the chance of measurable rain or snow is 27%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Des Moines.
- Jan 31° 14°
- Feb 36° 18°
- Mar 49° 30°
- Apr 62° 41°
- May 72° 52°
- Jun 82° 62°
- Jul 86° 66°
- Aug 84° 64°
- Sep 77° 55°
- Oct 63° 43°
- Nov 48° 30°
- Dec 36° 20°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
What is the weather like in Des Moines each month?
July is the warmest month, with normal highs of 86°F; January the coldest, with normal lows of 14°F. The most precipitation falls in June (5.26 in), the least in January (1.08 in).
Each month has its own page with the day-by-day normals, the month's records and its recent years:
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 31°F | 14°F | 22.3°F | 1.08 | 9.4 | 8 | <1 | 30 | 9 h 30 min |
| February | 36°F | 18°F | 26.9°F | 1.34 | 10.2 | 8 | <1 | 25 | 10 h 40 min |
| March | 49°F | 30°F | 39.4°F | 2.17 | 4.4 | 10 | <1 | 19 | 11 h 50 min |
| April | 62°F | 41°F | 51.3°F | 4.02 | 1.2 | 12 | <1 | 6 | 13 h 20 min |
| May | 72°F | 52°F | 62.4°F | 5.24 | 0.2 | 13 | 1 | <1 | 14 h 30 min |
| June | 82°F | 62°F | 72.2°F | 5.26 | 0.0 | 12 | 4 | <1 | 15 h 10 min |
| July | 86°F | 66°F | 76.0°F | 3.82 | 0.0 | 10 | 9 | <1 | 15 h |
| August | 84°F | 64°F | 73.9°F | 4.17 | 0.0 | 9 | 6 | <1 | 13 h 50 min |
| September | 77°F | 55°F | 66.2°F | 3.18 | 0.0 | 8 | 2 | <1 | 12 h 30 min |
| October | 63°F | 43°F | 53.2°F | 2.78 | 0.5 | 9 | <1 | 4 | 11 h 10 min |
| November | 48°F | 30°F | 39.3°F | 1.91 | 2.7 | 8 | <1 | 17 | 9 h 50 min |
| December | 36°F | 20°F | 27.7°F | 1.58 | 7.9 | 8 | <1 | 27 | 9 h 10 min |
| Year (annual) | 61°F | 41°F | 50.9°F | 36.55 | 36.5 | 113 | 22 | 128 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | −1°C | −10°C | −5.4°C | 27 mm | 24 cm |
| February | 2°C | −8°C | −2.8°C | 34 mm | 26 cm |
| March | 10°C | −1°C | 4.1°C | 55 mm | 11 cm |
| April | 17°C | 5°C | 10.7°C | 102 mm | 3 cm |
| May | 22°C | 11°C | 16.9°C | 133 mm | 1 cm |
| June | 28°C | 17°C | 22.3°C | 134 mm | 0 cm |
| July | 30°C | 19°C | 24.4°C | 97 mm | 0 cm |
| August | 29°C | 18°C | 23.3°C | 106 mm | 0 cm |
| September | 25°C | 13°C | 19.0°C | 81 mm | 0 cm |
| October | 17°C | 6°C | 11.8°C | 71 mm | 1 cm |
| November | 9°C | −1°C | 4.1°C | 49 mm | 7 cm |
| December | 2°C | −7°C | −2.4°C | 40 mm | 20 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USW00014933; annual normals. Wet days: 0.01 inch or more; 90°F days and freezing nights: NOAA's day counts. Daylight: sunrise to sunset on the 15th, computed from the latitude.
When is the best weather to visit Des Moines?
Normal highs sit between 65°F and 85°F in May, June, August and September. Of those, September has the fewest days with rain (8).
That is a measurement, not a recommendation: it counts the months whose normal afternoon high sits between 65°F and 85°F, where a light layer is enough by day.
Source: NOAA NCEI 1991-2020 monthly normals, station USW00014933.
When is the last frost in Des Moines?
In Des Moines, the last spring frost (32°F) comes after April 18 in half of years and after May 2 in one year in ten; the first autumn frost comes before October 20 in half of years and before October 4 in one year in ten.
Frost-free in half of yearsFrost in 1 to 9 years out of 10Frost most years
- Last spring frost, half of years after
- April 181 year in 10 after May 2; 9 in 10 after April 4
- First autumn frost, half of years before
- October 201 year in 10 before October 4; 9 in 10 before November 1
NOAA puts the median frost-free season at 184 days, and the season without a hard freeze (28°F) at 203 days.
A hard freeze (28°F) comes after April 8 in half of springs and before October 30 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Des Moines in zone 5b across its 11 ZIP code areas (5b in 50317, the largest). By the map's own method, the average of each year's coldest night over 1991-2020, Des Moines's NOAA station is in zone 5b: the coldest night of a typical year reaches −11°F (30 complete years).
Frost dates for every NOAA station in Iowa · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USW00014933; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; the station zone: ACIS daily lows, 1991-2020. A 10% date means one year in ten has a frost after it in spring or before it in autumn.
What hardiness zone is each Des Moines ZIP code in?
The USDA's 2023 map gives each ZIP code area one zone. Des Moines's 11 ZIP code areas are all in zone 5b. Each ZIP's frost dates are in the frost tool.
Source: USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026; ZIP areas in the place: Census Bureau 2020 ZCTA-to-place relationship file. A ZIP area counts when at least a tenth of its land (and 0.5 km²) lies in the place.
How hot and how cold does it get in Des Moines?
In a normal year in Des Moines, 22 days a year reach 90°F (1 of them 100°F or more), 128 nights fall to 32°F or colder and 113 days bring measurable precipitation.
- Days at 90°F or more
- 22a normal year
- Days at 100°F or more
- 1a normal year
- Nights at 32°F or colder
- 128a normal year
- Days that stay below freezing
- 46high of 32°F or less
- Days with 0.01 inch of precipitation
- 113a normal year
- Days with 1 inch of snow or more
- 11a normal year
The highest temperature in Des Moines's official record (kept by the National Weather Service since 1878) is 110°F, on July 25, 1936; the lowest is −30°F, on January 5, 1884.
The wettest calendar year on that record is 1881, with 56.81 in; the snowiest season is 1911–12, with 72.0 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USW00014933; records: ACIS (NOAA Regional Climate Centers), NWS threaded record DSMthr. Records use complete months only; a month missing more than three days is left out.
How humid and windy is Des Moines, and how clear are its skies?
The summer (June-August) dew point averages 63°F. The muggiest month is July, with an average dew point of 64°F; the driest air comes in January (16°F). March is the windiest month (11.3 mph on average), and August has the most clear or nearly clear hours (56%).
| Month | Dew point | Humidity | Afternoon humidity | Wind | Clear or few clouds | Overcast |
|---|---|---|---|---|---|---|
| January | 16°F | 72% | 61% | 10.0 mph | 41% | 44% |
| February | 21°F | 68% | 55% | 10.6 mph | 39% | 43% |
| March | 32°F | 59% | 44% | 11.3 mph | 36% | 42% |
| April | 43°F | 61% | 46% | 10.5 mph | 34% | 41% |
| May | 55°F | 66% | 51% | 8.9 mph | 36% | 33% |
| June | 63°F | 68% | 53% | 8.5 mph | 51% | 20% |
| July | 64°F | 69% | 53% | 7.6 mph | 45% | 21% |
| August | 62°F | 70% | 51% | 7.9 mph | 56% | 18% |
| September | 48°F | 65% | 46% | 9.0 mph | 55% | 22% |
| October | 35°F | 65% | 49% | 10.1 mph | 45% | 36% |
| November | 25°F | 71% | 58% | 10.1 mph | 39% | 43% |
| December | 17°F | 74% | 63% | 10.1 mph | 41% | 44% |
Source: NOAA NCEI 1991-2020 hourly normals, station USW00014933. Monthly averages of all hours; afternoon humidity at 3 p.m. local standard time; sky as the share of hours NOAA's observations rate clear or few clouds (a dash where NOAA publishes no sky value).
How sunny is Des Moines?
Over a year 75% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Des Moines, 4.1 kWh per square metre a day. July is the sunniest month (81%) and December the cloudiest (68%). Among the 459 U.S. places of 50,000 or more, that ranks tied 304th (with 25 others) in sunshine.
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 68% | 2.0 |
| February | 74% | 3.0 |
| March | 70% | 3.8 |
| April | 69% | 4.8 |
| May | 72% | 5.7 |
| June | 77% | 6.3 |
| July | 81% | 6.4 |
| August | 80% | 5.5 |
| September | 80% | 4.6 |
| October | 73% | 3.1 |
| November | 72% | 2.2 |
| December | 68% | 1.7 |
Source: NASA POWER solar climatology, 2001-2020 (CERES SYN1deg). Satellite-based, for the 1-degree cell (about 100 km across) around the station, so it describes the area rather than the airport.
How much heating and cooling does Des Moines need?
A normal year in Des Moines brings 6,178 heating degree days, 15% more than the median U.S. place (5,373), and 1,070 cooling degree days, 18% more than the median (908). Seven months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 3,476 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,322 | 0 |
| February | 1,068 | 0 |
| March | 796 | 2 |
| April | 421 | 10 |
| May | 153 | 71 |
| June | 15 | 230 |
| July | 1 | 342 |
| August | 4 | 280 |
| September | 86 | 120 |
| October | 383 | 16 |
| November | 773 | 0 |
| December | 1,156 | 0 |
| Year (annual) | 6,178 | 1,070 |
Source: NOAA NCEI 1991-2020 monthly normals, station USW00014933. A degree day is one degree of a day's mean temperature below 65°F (heating) or above it (cooling); utilities use them to estimate energy use.
Has Des Moines been warmer than normal lately?
2025 averaged 52.4°F, 1.5°F above the 1991-2020 normal of 50.9°F. 4 of the 5 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. | Snow |
|---|---|---|---|---|
| 2021 | 52.8°F | +1.9°F | 28.86 | 35.9 |
| 2022 | 50.4°F | −0.5°F | 30.59 | 44.4 |
| 2023 | 53.7°F | +2.8°F | 24.93 | 25.9 |
| 2024 | 54.9°F | +4.0°F | 36.49 | 35.4 |
| 2025 | 52.4°F | +1.5°F | 35.18 | 30.2 |
Over 145 complete years from 1879 to 2025, the station's annual mean temperature rose at a fitted 0.5°F per century (+0.03°C per decade). A fitted rate summarizes the whole record; single years swing well above and below it.
Source: observed years: ACIS, station USW00014933; trend: NOAA GHCN-Monthly v4. A year counts only with all twelve months complete.
How does Des Moines's climate compare?
Des Moines is warmer than 122 of the other 131 places with their own NOAA record in Iowa, and wetter than 65. Across the 7,247 U.S. stations with normals, its annual mean of 50.9°F is warmer than 44%.
In the Köppen classification computed from these normals, Des Moines is Dfa: continental, no dry season, hot summer. What the classes mean.
Places with the most similar year elsewhere
Measured month by month on the normal high, low and precipitation, among places of 20,000 or more people in other states:
Source: NOAA NCEI 1991-2020 normals for every station PlainClimate covers. Similarity: the root-mean-square difference of the 36 monthly figures, precipitation weighted so an inch counts like 6°F.
Which places near Des Moines share this climate record?
10 places have no NOAA station with 1991-2020 normals of their own, and this station is the nearest full record. A place's own climate can differ from these figures, by several degrees where it sits much higher or lower than the station, nearer the coast, or inside a large city's heat; for the larger places the next nearest records are named with their yearly mean, so the spread around them is visible, and places of 50,000 or more have their own page with NOAA's gridded normals.
- West Des Moines, IAalso near: Des Moines Weather Office-Johnston (13 mi, 50.3°F a year); Ankeny (14 mi, 49.5°F a year)73,664 people · 7 mi W
- Waukee, IA34,420 people · 12 mi W
- Clive, IA19,508 people · 9 mi NW
- Norwalk, IA15,396 people · 4 mi SW
- Pleasant Hill, IA11,942 people · 9 mi NE
- Windsor Heights, IA5,106 people · 6 mi NW
- Carlisle, IA4,381 people · 8 mi E
- Hartford, IA729 people · 14 mi E
- Cumming, IA527 people · 7 mi SW
- Runnells, IA467 people · 15 mi E
Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.
What do Des Moines's other NOAA stations record?
2 more NOAA stations keep 1991-2020 normals in or near Des Moines. This page uses Des Moines International Airport; the others differ by site and elevation, and the linked ones have pages of their own:
| Station | From the center | Elevation | Year | Jan low | Jul high | Precip. | Snow | Last frost |
|---|---|---|---|---|---|---|---|---|
| Des Moines Weather Office-Johnston USC00132209 | 13 mi NW | 959 ft | 50.3°F | 13°F | 85°F | 36.2 | 38 | April 19 |
| Des Moines (17 mi E) USW00054902 | 17 mi E | 921 ft | 49.5°F | 13°F | 84°F | 36.6 | – | April 21 |
Source: NOAA NCEI 1991-2020 normals for each station. Last frost: the median last spring date of 32°F.
Questions about Des Moines's climate
What is the coldest month in Des Moines?
January, with a normal high of 31°F and a normal low of 14°F. The warmest is July (86°F by day, 66°F at night).
Does it snow in Des Moines?
Yes: 37 inches in a normal year, falling on 25 days with 0.1 inch or more, the most in February (10.2 inches).
What is the rainiest month in Des Moines?
June, with 5.26 in of precipitation in a normal year; the driest is January with 1.08 in.
What plant hardiness zone is Des Moines in?
The USDA's 2023 map puts Des Moines in zone 5b across its 11 ZIP code areas (5b in 50317, the largest). By the same method at Des Moines's NOAA station, the coldest night of a typical year reaches −11°F (30 years, 1991-2020): zone 5b.
How late can frost come in Des Moines?
In half of years the last 32°F night comes after April 18; in one year in ten it comes after May 2. Waiting until May 2 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Des Moines in OctoberThis month day by day, its records and recent years
- Iowa climateThe statewide normals and every place in the state
- Indianola, IA12 miles from this station, 49.9°F a year
- Ankeny, IA14 miles from this station, 49.5°F a year
- Des Moines Weather Office-Johnston, IA14 miles from this station, 50.3°F a year
- Winterset, IA24 miles from this station, 48.1°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made