Prairie City, Illinois climate: Normal weather by month, frost dates and records
Prairie City's normal year runs from 16°F January nights to 86°F July afternoons, with 38.5 inches of precipitation and 21 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 10.8°C, January lows of −9°C, July highs of 30°C, 977 mm of precipitation a year.
- NOAA stationPrairie City (2 mi S)
- Station IDUSC00116970
- Location40.59°N 90.46°W
- Elevation650 ft (198 m)
- Population399
On October 23, the normal high in Prairie City is 63°F and the normal low 40°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 Prairie City.
- Jan 33° 16°
- Feb 38° 19°
- Mar 51° 29°
- Apr 64° 40°
- May 74° 52°
- Jun 82° 62°
- Jul 86° 64°
- Aug 84° 63°
- Sep 78° 55°
- Oct 66° 43°
- Nov 50° 31°
- Dec 38° 22°
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 Prairie City each month?
July is the warmest month, with normal highs of 86°F; January the coldest, with normal lows of 16°F. The most precipitation falls in May (5.05 in), the least in December (1.80 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 33°F | 16°F | 24.4°F | 1.91 | 5.7 | 7 | <1 | 28 | 9 h 30 min |
| February | 38°F | 19°F | 28.5°F | 1.92 | 6.0 | 8 | <1 | 25 | 10 h 40 min |
| March | 51°F | 29°F | 39.6°F | 2.68 | 2.5 | 9 | <1 | 20 | 11 h 50 min |
| April | 64°F | 40°F | 51.7°F | 3.79 | 1.0 | 11 | <1 | 7 | 13 h 10 min |
| May | 74°F | 52°F | 62.9°F | 5.05 | 0.0 | 12 | 2 | <1 | 14 h 20 min |
| June | 82°F | 62°F | 72.0°F | 4.82 | 0.0 | 10 | 6 | <1 | 15 h |
| July | 86°F | 64°F | 75.1°F | 4.10 | 0.0 | 9 | 9 | <1 | 14 h 50 min |
| August | 84°F | 63°F | 73.0°F | 3.21 | 0.0 | 8 | 6 | <1 | 13 h 50 min |
| September | 78°F | 55°F | 66.4°F | 3.77 | 0.0 | 7 | 3 | <1 | 12 h 30 min |
| October | 66°F | 43°F | 54.5°F | 2.99 | 0.0 | 9 | <1 | 4 | 11 h 10 min |
| November | 50°F | 31°F | 40.5°F | 2.42 | 1.1 | 8 | <1 | 17 | 10 h |
| December | 38°F | 22°F | 29.9°F | 1.80 | 5.0 | 8 | <1 | 26 | 9 h 20 min |
| Year (annual) | 62°F | 41°F | 51.5°F | 38.46 | 21.3 | 106 | 26 | 127 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | 0°C | −9°C | −4.2°C | 49 mm | 14 cm |
| February | 3°C | −7°C | −1.9°C | 49 mm | 15 cm |
| March | 10°C | −2°C | 4.2°C | 68 mm | 6 cm |
| April | 18°C | 4°C | 10.9°C | 96 mm | 3 cm |
| May | 23°C | 11°C | 17.2°C | 128 mm | 0 cm |
| June | 28°C | 16°C | 22.2°C | 122 mm | 0 cm |
| July | 30°C | 18°C | 23.9°C | 104 mm | 0 cm |
| August | 29°C | 17°C | 22.8°C | 82 mm | 0 cm |
| September | 26°C | 13°C | 19.1°C | 96 mm | 0 cm |
| October | 19°C | 6°C | 12.5°C | 76 mm | 0 cm |
| November | 10°C | −1°C | 4.7°C | 61 mm | 3 cm |
| December | 3°C | −6°C | −1.2°C | 46 mm | 13 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00116970; 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 Prairie City?
Normal highs sit between 65°F and 85°F in May, June, August, September and October. Of those, September has the fewest days with rain (7).
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 USC00116970.
When is the last frost in Prairie City?
In Prairie City, the last spring frost (32°F) comes after April 17 in half of years and after May 2 in one year in ten; the first autumn frost comes before October 22 in half of years and before October 7 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 171 year in 10 after May 2; 9 in 10 after April 4
- First autumn frost, half of years before
- October 221 year in 10 before October 7; 9 in 10 before November 1
NOAA puts the median frost-free season at 185 days, and the season without a hard freeze (28°F) at 204 days.
A hard freeze (28°F) comes after April 7 in half of springs and before October 30 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Prairie City in zone 6a in ZIP code 61470, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, Prairie City's NOAA station is in zone 5b: the coldest night of a typical year reaches −10°F (20 complete years); the map interpolates between stations and terrain, so the station and the ZIP area can differ by half a zone.
Frost dates for every NOAA station in Illinois · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00116970; 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 Prairie City?
In a normal year in Prairie City, 26 days a year reach 90°F (1 of them 100°F or more), 127 nights fall to 32°F or colder and 106 days bring measurable precipitation.
- Days at 90°F or more
- 26a 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
- 35high of 32°F or less
- Days with 0.01 inch of precipitation
- 106a normal year
- Days with 1 inch of snow or more
- 9a normal year
The highest temperature in this station's record (since 2000) is 106°F, on July 25, 2005; the lowest is −22°F, on February 4, 2014.
The wettest calendar year on that record is 2009, with 53.26 in; the snowiest season is 2009–10, with 33.2 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00116970; records: ACIS (NOAA Regional Climate Centers), station USC00116970. Records use complete months only; a month missing more than three days is left out.
How sunny is Prairie City?
Over a year 74% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Prairie City, 4.1 kWh per square metre a day. July is the sunniest month (82%) and January the cloudiest (63%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 63% | 1.9 |
| February | 68% | 2.8 |
| March | 68% | 3.8 |
| April | 70% | 4.9 |
| May | 73% | 5.6 |
| June | 79% | 6.3 |
| July | 82% | 6.4 |
| August | 81% | 5.5 |
| September | 82% | 4.7 |
| October | 73% | 3.2 |
| November | 70% | 2.2 |
| December | 63% | 1.6 |
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 Prairie City need?
A normal year in Prairie City brings 5,886 heating degree days, 10% more than the median U.S. place (5,373), and 1,017 cooling degree days, 12% 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 3,482 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,260 | 0 |
| February | 1,023 | 0 |
| March | 788 | 2 |
| April | 408 | 9 |
| May | 142 | 77 |
| June | 12 | 222 |
| July | 2 | 314 |
| August | 6 | 254 |
| September | 74 | 117 |
| October | 347 | 22 |
| November | 735 | 1 |
| December | 1,088 | 0 |
| Year (annual) | 5,886 | 1,017 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00116970. 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 Prairie City been warmer than normal lately?
2024 averaged 54.5°F, 3.0°F above the 1991-2020 normal of 51.5°F. 3 of the 4 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. | Snow |
|---|---|---|---|---|
| 2021 | 52.9°F | +1.4°F | 39.06 | 11.4 |
| 2022 | 50.6°F | −0.9°F | 28.24 | 29.4 |
| 2023 | 53.9°F | +2.4°F | 29.17 | 9.9 |
| 2024 | 54.5°F | +3.0°F | 38.53 | 16.4 |
Source: observed years: ACIS, station USC00116970. A year counts only with all twelve months complete.
How does Prairie City's climate compare?
Prairie City is warmer than 66 of the other 143 places with their own NOAA record in Illinois, and wetter than 44. Across the 7,247 U.S. stations with normals, its annual mean of 51.5°F is warmer than 47%.
In the Köppen classification computed from these normals, Prairie City 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 Prairie City 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.
- Macomb, IL14,765 people · 14 mi SW
- Bushnell, IL2,649 people · 3 mi SW
- Good Hope, IL353 people · 11 mi W
- Table Grove, IL333 people · 16 mi S
- Bardolph, IL204 people · 8 mi SW
- Smithfield, IL184 people · 12 mi SE
- Adair, IL148 people · 12 mi S
- Marietta, IL100 people · 7 mi SE
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 Prairie City's climate
What is the coldest month in Prairie City?
January, with a normal high of 33°F and a normal low of 16°F. The warmest is July (86°F by day, 64°F at night).
Does it snow in Prairie City?
Yes: 21 inches in a normal year, falling on 13 days with 0.1 inch or more, the most in February (6.0 inches).
What is the rainiest month in Prairie City?
May, with 5.05 in of precipitation in a normal year; the driest is December with 1.80 in.
What plant hardiness zone is Prairie City in?
The USDA's 2023 map puts Prairie City in zone 6a in ZIP code 61470, the nearest ZIP area. By the same method at Prairie City's NOAA station, the coldest night of a typical year reaches −10°F (20 years, 1991-2020): zone 5b.
How late can frost come in Prairie City?
In half of years the last 32°F night comes after April 17; 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
- Illinois climateThe statewide normals and every place in the state
- Avon, IL5 miles from this station, 49.3°F a year
- Knoxville, IL24 miles from this station, 50.4°F a year
- Galesburg, IL25 miles from this station, 50.2°F a year
- Monmouth, IL26 miles from this station, 50.6°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made