Fairfield, Iowa climate: Normal weather by month, frost dates and records
Fairfield's normal year runs from 14°F January nights to 84°F July afternoons, with 38.4 inches of precipitation and 22 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 9.8°C, January lows of −10°C, July highs of 29°C, 976 mm of precipitation a year.
- NOAA stationFairfield
- Station IDUSC00132789
- Location41.02°N 91.96°W
- Elevation740 ft (226 m)
- From the center1 miles
- Population9,511
On October 23, the normal high in Fairfield is 59°F and the normal low 39°F, and the chance of measurable rain or snow is 28%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Fairfield.
- Jan 31° 14°
- Feb 36° 18°
- Mar 49° 28°
- Apr 62° 39°
- May 71° 50°
- Jun 81° 60°
- Jul 84° 64°
- Aug 83° 61°
- Sep 76° 53°
- Oct 63° 41°
- Nov 48° 30°
- Dec 35° 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 Fairfield each month?
July is the warmest month, with normal highs of 84°F; January the coldest, with normal lows of 14°F. The most precipitation falls in May (5.51 in), the least in January (1.52 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 31°F | 14°F | 22.1°F | 1.52 | 6.2 | 8 | <1 | 29 | 9 h 30 min |
| February | 36°F | 18°F | 26.6°F | 1.80 | 7.2 | 8 | <1 | 25 | 10 h 40 min |
| March | 49°F | 28°F | 38.3°F | 2.40 | 2.7 | 8 | <1 | 19 | 11 h 50 min |
| April | 62°F | 39°F | 50.4°F | 3.71 | 1.0 | 11 | <1 | 6 | 13 h 20 min |
| May | 71°F | 50°F | 60.5°F | 5.51 | 0.0 | 13 | 1 | <1 | 14 h 30 min |
| June | 81°F | 60°F | 70.0°F | 5.11 | 0.0 | 11 | 4 | <1 | 15 h 10 min |
| July | 84°F | 64°F | 73.8°F | 3.96 | 0.0 | 9 | 10 | <1 | 14 h 50 min |
| August | 83°F | 61°F | 71.9°F | 3.83 | 0.0 | 9 | 7 | <1 | 13 h 50 min |
| September | 76°F | 53°F | 64.4°F | 3.58 | 0.0 | 8 | 3 | <1 | 12 h 30 min |
| October | 63°F | 41°F | 52.0°F | 3.00 | 0.2 | 9 | <1 | 5 | 11 h 10 min |
| November | 48°F | 30°F | 38.7°F | 2.28 | 0.9 | 7 | <1 | 17 | 10 h |
| December | 35°F | 20°F | 27.6°F | 1.72 | 3.5 | 8 | <1 | 27 | 9 h 20 min |
| Year (annual) | 60°F | 40°F | 49.7°F | 38.42 | 21.7 | 110 | 24 | 127 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | −1°C | −10°C | −5.5°C | 39 mm | 16 cm |
| February | 2°C | −8°C | −3.0°C | 46 mm | 18 cm |
| March | 9°C | −2°C | 3.5°C | 61 mm | 7 cm |
| April | 17°C | 4°C | 10.2°C | 94 mm | 3 cm |
| May | 22°C | 10°C | 15.8°C | 140 mm | 0 cm |
| June | 27°C | 15°C | 21.1°C | 130 mm | 0 cm |
| July | 29°C | 18°C | 23.2°C | 101 mm | 0 cm |
| August | 28°C | 16°C | 22.2°C | 97 mm | 0 cm |
| September | 24°C | 12°C | 18.0°C | 91 mm | 0 cm |
| October | 17°C | 5°C | 11.1°C | 76 mm | 1 cm |
| November | 9°C | −1°C | 3.7°C | 58 mm | 2 cm |
| December | 2°C | −7°C | −2.4°C | 44 mm | 9 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00132789; 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 Fairfield?
Normal highs sit between 65°F and 85°F in May, June, July, 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 USC00132789.
When is the last frost in Fairfield?
In Fairfield, the last spring frost (32°F) comes after April 27 in half of years and after May 14 in one year in ten; the first autumn frost comes before October 12 in half of years and before September 27 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 271 year in 10 after May 14; 9 in 10 after April 13
- First autumn frost, half of years before
- October 121 year in 10 before September 27; 9 in 10 before October 25
NOAA puts the median frost-free season at 168 days, and the season without a hard freeze (28°F) at 190 days.
A hard freeze (28°F) comes after April 15 in half of springs and before October 22 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Fairfield in zone 5b in ZIP code 52557. By the map's own method, the average of each year's coldest night over 1991-2020, Fairfield's NOAA station is in zone 5b: the coldest night of a typical year reaches −12°F (29 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 USC00132789; 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.
How hot and how cold does it get in Fairfield?
In a normal year in Fairfield, 24 days a year reach 90°F (1 of them 100°F or more), 127 nights fall to 32°F or colder and 110 days bring measurable precipitation.
- Days at 90°F or more
- 24a normal year
- Days at 100°F or more
- 1a normal year
- Nights at 32°F or colder
- 127a normal year
- Days that stay below freezing
- 41high of 32°F or less
- Days with 0.01 inch of precipitation
- 110a normal year
- Days with 1 inch of snow or more
- 10a normal year
The highest temperature in this station's record (since 1893) is 114°F, on July 15, 1936; the lowest is −31°F, on February 3, 1996.
The wettest calendar year on that record is 2010, with 53.17 in; the snowiest season is 1959–60, with 60.5 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00132789; records: ACIS (NOAA Regional Climate Centers), station USC00132789. Records use complete months only; a month missing more than three days is left out.
How sunny is Fairfield?
Over a year 74% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Fairfield, 4.0 kWh per square metre a day. July is the sunniest month (81%) and December the cloudiest (63%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 65% | 1.9 |
| February | 71% | 2.9 |
| March | 69% | 3.8 |
| April | 70% | 4.8 |
| May | 72% | 5.6 |
| June | 77% | 6.2 |
| July | 81% | 6.3 |
| August | 80% | 5.5 |
| September | 81% | 4.6 |
| October | 72% | 3.0 |
| November | 70% | 2.1 |
| December | 63% | 1.5 |
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 Fairfield need?
A normal year in Fairfield brings 6,377 heating degree days, 19% more than the median U.S. place (5,373), and 842 cooling degree days, 7% fewer 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 3,143 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,330 | 0 |
| February | 1,074 | 0 |
| March | 829 | 1 |
| April | 447 | 8 |
| May | 189 | 51 |
| June | 26 | 176 |
| July | 4 | 278 |
| August | 11 | 226 |
| September | 107 | 91 |
| October | 413 | 11 |
| November | 788 | 0 |
| December | 1,161 | 0 |
| Year (annual) | 6,377 | 842 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00132789. 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 Fairfield been warmer than normal lately?
2025 averaged 52.1°F, 2.4°F above the 1991-2020 normal of 49.7°F. 2 of the 2 complete years since 2022 ran warmer than the normal.
| Year | Mean | Against normal | Precip. | Snow |
|---|---|---|---|---|
| 2022 | 50.3°F | +0.6°F | 27.12 | 26.9 |
| 2025 | 52.1°F | +2.4°F | 34.52 | 17.2 |
Over 100 complete years from 1895 to 2025, the station's annual mean temperature rose at a fitted 1.4°F per century (+0.08°C per decade). A fitted rate summarizes the whole record; single years swing well above and below it.
Source: observed years: ACIS, station USC00132789; trend: NOAA GHCN-Monthly v4. A year counts only with all twelve months complete.
How does Fairfield's climate compare?
Fairfield is warmer than 102 of the other 131 places with their own NOAA record in Iowa, and wetter than 100. Across the 7,247 U.S. stations with normals, its annual mean of 49.7°F is warmer than 39%.
In the Köppen classification computed from these normals, Fairfield 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 Fairfield share this climate record?
8 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.
- Eldon, IA788 people · 15 mi SW
- Richland, IA532 people · 12 mi N
- Batavia, IA434 people · 11 mi W
- Birmingham, IA371 people · 10 mi S
- Maharishi Vedic City, IA290 people · 4 mi NW
- Libertyville, IA278 people · 7 mi SW
- Packwood, IA186 people · 10 mi NW
- Pleasant Plain, IA83 people · 10 mi NE
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 Fairfield's climate
What is the coldest month in Fairfield?
January, with a normal high of 31°F and a normal low of 14°F. The warmest is July (84°F by day, 64°F at night).
Does it snow in Fairfield?
Yes: 22 inches in a normal year, falling on 15 days with 0.1 inch or more, the most in February (7.2 inches).
What is the rainiest month in Fairfield?
May, with 5.51 in of precipitation in a normal year; the driest is January with 1.52 in.
What plant hardiness zone is Fairfield in?
The USDA's 2023 map puts Fairfield in zone 5b in ZIP code 52557. By the same method at Fairfield's NOAA station, the coldest night of a typical year reaches −12°F (29 years, 1991-2020): zone 5b.
How late can frost come in Fairfield?
In half of years the last 32°F night comes after April 27; in one year in ten it comes after May 14. Waiting until May 14 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Iowa climateThe statewide normals and every place in the state
- Keosauqua, IA20 miles from this station, 50.6°F a year
- Mount Pleasant, IA21 miles from this station, 49.6°F a year
- Washington, IA22 miles from this station, 49.3°F a year
- Sigourney, IA26 miles from this station, 48.9°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made