Ankeny, Iowa climate: Normal weather by month, frost dates and records
Ankeny's normal year runs from 12°F January nights to 86°F July afternoons, with 37.0 inches of precipitation and 25 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 9.7°C, January lows of −11°C, July highs of 30°C, 941 mm of precipitation a year.
- NOAA stationAnkeny
- Station IDUSC00130241
- Location41.73°N 93.65°W
- Elevation975 ft (297 m)
- From the center3 miles
- Population76,727
On October 23, the normal high in Ankeny is 60°F and the normal low 38°F, and the chance of measurable rain or snow is 25%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Ankeny.
- Jan 30° 12°
- Feb 34° 16°
- Mar 47° 27°
- Apr 61° 38°
- May 72° 50°
- Jun 82° 61°
- Jul 86° 65°
- Aug 84° 62°
- Sep 77° 53°
- Oct 64° 41°
- Nov 48° 29°
- Dec 35° 18°
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 Ankeny each month?
July is the warmest month, with normal highs of 86°F; January the coldest, with normal lows of 12°F. The most precipitation falls in June (5.37 in), the least in January (0.97 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 | 30°F | 12°F | 20.6°F | 0.97 | 6.2 | 6 | <1 | 30 | 9 h 30 min |
| February | 34°F | 16°F | 25.1°F | 0.99 | 8.0 | 6 | <1 | 27 | 10 h 30 min |
| March | 47°F | 27°F | 37.4°F | 2.01 | 3.7 | 8 | <1 | 24 | 11 h 50 min |
| April | 61°F | 38°F | 49.5°F | 4.00 | 0.7 | 11 | <1 | 10 | 13 h 20 min |
| May | 72°F | 50°F | 61.1°F | 5.26 | 0.0 | 12 | 1 | 1 | 14 h 30 min |
| June | 82°F | 61°F | 71.3°F | 5.37 | 0.0 | 11 | 4 | <1 | 15 h 10 min |
| July | 86°F | 65°F | 75.2°F | 4.19 | 0.0 | 9 | 9 | <1 | 15 h |
| August | 84°F | 62°F | 72.7°F | 4.72 | 0.0 | 10 | 6 | <1 | 13 h 50 min |
| September | 77°F | 53°F | 65.0°F | 3.62 | 0.0 | 8 | 3 | 1 | 12 h 30 min |
| October | 64°F | 41°F | 52.0°F | 2.67 | 0.6 | 8 | <1 | 8 | 11 h 10 min |
| November | 48°F | 29°F | 38.4°F | 1.86 | 1.0 | 7 | <1 | 21 | 9 h 50 min |
| December | 35°F | 18°F | 26.3°F | 1.39 | 4.5 | 7 | <1 | 29 | 9 h 10 min |
| Year (annual) | 60°F | 39°F | 49.5°F | 37.05 | 24.7 | 102 | 23 | 150 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | −1°C | −11°C | −6.3°C | 25 mm | 16 cm |
| February | 1°C | −9°C | −3.8°C | 25 mm | 20 cm |
| March | 9°C | −3°C | 3.0°C | 51 mm | 9 cm |
| April | 16°C | 3°C | 9.7°C | 102 mm | 2 cm |
| May | 22°C | 10°C | 16.2°C | 134 mm | 0 cm |
| June | 28°C | 16°C | 21.8°C | 136 mm | 0 cm |
| July | 30°C | 18°C | 24.0°C | 106 mm | 0 cm |
| August | 29°C | 17°C | 22.6°C | 120 mm | 0 cm |
| September | 25°C | 12°C | 18.3°C | 92 mm | 0 cm |
| October | 18°C | 5°C | 11.1°C | 68 mm | 2 cm |
| November | 9°C | −2°C | 3.6°C | 47 mm | 3 cm |
| December | 2°C | −8°C | −3.2°C | 35 mm | 11 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00130241; 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 Ankeny?
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 USC00130241.
When is the last frost in Ankeny?
In Ankeny, the last spring frost (32°F) comes after April 23 in half of years and after May 6 in one year in ten; the first autumn frost comes before October 15 in half of years and before September 30 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 231 year in 10 after May 6; 9 in 10 after April 8
- First autumn frost, half of years before
- October 151 year in 10 before September 30; 9 in 10 before October 28
NOAA puts the median frost-free season at 173 days, and the season without a hard freeze (28°F) at 193 days.
A hard freeze (28°F) comes after April 13 in half of springs and before October 25 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Ankeny in zone 5b across its 2 ZIP code areas (5b in 50021, the largest). By the map's own method, the average of each year's coldest night over 1991-2020, Ankeny's NOAA station is in zone 5b: the coldest night of a typical year reaches −13°F (19 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 USC00130241; 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 Ankeny ZIP code in?
The USDA's 2023 map gives each ZIP code area one zone. Ankeny's 2 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 Ankeny?
In a normal year in Ankeny, 23 days a year reach 90°F (1 of them 100°F or more), 150 nights fall to 32°F or colder and 102 days bring measurable precipitation.
- Days at 90°F or more
- 23a normal year
- Days at 100°F or more
- 1a normal year
- Nights at 32°F or colder
- 150a normal year
- Days that stay below freezing
- 51high of 32°F or less
- Days with 0.01 inch of precipitation
- 102a normal year
- Days with 1 inch of snow or more
- 9a normal year
The highest temperature in this station's record (since 1950) is 106°F, on August 16, 1983; the lowest is −34°F, on February 3, 1996.
The wettest calendar year on that record is 2008, with 51.82 in; the snowiest season is 1981–82, with 60.1 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00130241; records: ACIS (NOAA Regional Climate Centers), station USC00130241. Records use complete months only; a month missing more than three days is left out.
How sunny is Ankeny?
Over a year 75% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Ankeny, 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 Ankeny need?
A normal year in Ankeny brings 6,547 heating degree days, 22% more than the median U.S. place (5,373), and 958 cooling degree days, 6% 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 3,262 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,376 | 0 |
| February | 1,117 | 0 |
| March | 857 | 1 |
| April | 471 | 7 |
| May | 180 | 59 |
| June | 20 | 209 |
| July | 3 | 319 |
| August | 8 | 247 |
| September | 103 | 103 |
| October | 414 | 13 |
| November | 800 | 0 |
| December | 1,198 | 0 |
| Year (annual) | 6,547 | 958 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00130241. 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 Ankeny been warmer than normal lately?
Over 46 complete years from 1952 to 2020, the station's annual mean temperature rose at a fitted 4.1°F per century (+0.23°C per decade). A fitted rate summarizes the whole record; single years swing well above and below it.
Source: trend: NOAA GHCN-Monthly v4. A year counts only with all twelve months complete.
How does Ankeny's climate compare?
Ankeny is warmer than 97 of the other 131 places with their own NOAA record in Iowa, and wetter than 71. Across the 7,247 U.S. stations with normals, its annual mean of 49.5°F is warmer than 38%.
In the Köppen classification computed from these normals, Ankeny 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 Ankeny share this climate record?
6 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.
- Altoona, IA22,598 people · 10 mi SE
- Bondurant, IA9,511 people · 11 mi E
- Saylorville, IA3,559 people · 4 mi S
- Mitchellville, IA2,686 people · 15 mi E
- Elkhart, IA1,079 people · 8 mi NE
- Alleman, IA439 people · 6 mi N
Source: Census Bureau 2024 Gazetteer (place centers) and Vintage 2024 population estimates. Distance and direction from the station to each place's center.
Questions about Ankeny's climate
What is the coldest month in Ankeny?
January, with a normal high of 30°F and a normal low of 12°F. The warmest is July (86°F by day, 65°F at night).
Does it snow in Ankeny?
Yes: 25 inches in a normal year, falling on 15 days with 0.1 inch or more, the most in February (8.0 inches).
What is the rainiest month in Ankeny?
June, with 5.37 in of precipitation in a normal year; the driest is January with 0.97 in.
What plant hardiness zone is Ankeny in?
The USDA's 2023 map puts Ankeny in zone 5b across its 2 ZIP code areas (5b in 50021, the largest). By the same method at Ankeny's NOAA station, the coldest night of a typical year reaches −13°F (19 years, 1991-2020): zone 5b.
How late can frost come in Ankeny?
In half of years the last 32°F night comes after April 23; in one year in ten it comes after May 6. Waiting until May 6 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Ankeny in OctoberThis month day by day, its records and recent years
- Iowa climateThe statewide normals and every place in the state
- Des Moines Weather Office-Johnston, IA4 miles from this station, 50.3°F a year
- Des Moines, IA14 miles from this station, 50.9°F a year
- Ames, IA18 miles from this station, 48.5°F a year
- Boone, IA25 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