Robinson, Illinois climate: Normal weather by month, frost dates and records
Robinson's normal year runs from 20°F January nights to 87°F July afternoons, with 45.5 inches of precipitation a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 12.3°C, January lows of −7°C, July highs of 31°C, 1,155 mm of precipitation a year.
- NOAA stationRobinson
- Station IDUSC00117345
- Location39.01°N 87.78°W
- Elevation535 ft (163 m)
- Population7,053
On October 23, the normal high in Robinson is 65°F and the normal low 41°F, and the chance of measurable rain or snow is 26%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Robinson.
- Jan 37° 20°
- Feb 42° 23°
- Mar 53° 33°
- Apr 66° 43°
- May 76° 54°
- Jun 85° 63°
- Jul 87° 66°
- Aug 86° 63°
- Sep 81° 56°
- Oct 68° 44°
- Nov 54° 34°
- Dec 42° 25°
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 Robinson each month?
July is the warmest month, with normal highs of 87°F; January the coldest, with normal lows of 20°F. The most precipitation falls in April (5.17 in), the least in February (2.41 in).
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 37°F | 20°F | 28.6°F | 3.11 | 8 | <1 | 26 | 9 h 40 min |
| February | 42°F | 23°F | 32.8°F | 2.41 | 8 | <1 | 24 | 10 h 40 min |
| March | 53°F | 33°F | 42.7°F | 3.64 | 10 | <1 | 16 | 11 h 50 min |
| April | 66°F | 43°F | 54.2°F | 5.17 | 9 | <1 | 4 | 13 h 10 min |
| May | 76°F | 54°F | 65.0°F | 4.67 | 11 | 2 | <1 | 14 h 20 min |
| June | 85°F | 63°F | 74.1°F | 4.57 | 9 | 10 | <1 | 14 h 50 min |
| July | 87°F | 66°F | 76.5°F | 4.17 | 9 | 12 | <1 | 14 h 40 min |
| August | 86°F | 63°F | 74.5°F | 3.45 | 6 | 10 | <1 | 13 h 40 min |
| September | 81°F | 56°F | 68.2°F | 3.66 | 6 | 5 | <1 | 12 h 30 min |
| October | 68°F | 44°F | 56.0°F | 3.70 | 8 | 1 | 4 | 11 h 10 min |
| November | 54°F | 34°F | 43.6°F | 3.78 | 8 | <1 | 15 | 10 h 10 min |
| December | 42°F | 25°F | 33.5°F | 3.15 | 9 | <1 | 24 | 9 h 30 min |
| Year (annual) | 65°F | 44°F | 54.1°F | 45.48 | 99 | 40 | 114 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | 3°C | −7°C | −1.9°C | 79 mm |
| February | 6°C | −5°C | 0.4°C | 61 mm |
| March | 12°C | 0°C | 5.9°C | 92 mm |
| April | 19°C | 6°C | 12.3°C | 131 mm |
| May | 24°C | 12°C | 18.3°C | 119 mm |
| June | 29°C | 17°C | 23.4°C | 116 mm |
| July | 31°C | 19°C | 24.7°C | 106 mm |
| August | 30°C | 17°C | 23.6°C | 88 mm |
| September | 27°C | 13°C | 20.1°C | 93 mm |
| October | 20°C | 7°C | 13.3°C | 94 mm |
| November | 12°C | 1°C | 6.4°C | 96 mm |
| December | 5°C | −4°C | 0.8°C | 80 mm |
NOAA publishes no 1991-2020 snowfall normal for this station. The nearest record that keeps one, Palestine (8 miles away), gets 12 inches of snow in a normal year; elevation and distance can change that.
Source: NOAA NCEI 1991-2020 monthly normals, station USC00117345; 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 Robinson?
Normal highs sit between 65°F and 85°F in April, May, June, September and October. Of those, September has the fewest days with rain (6).
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 USC00117345.
When is the last frost in Robinson?
In Robinson, the last spring frost (32°F) comes after April 13 in half of years and after April 28 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 131 year in 10 after April 28; 9 in 10 after April 2
- First autumn frost, half of years before
- October 221 year in 10 before October 7; 9 in 10 before November 3
NOAA puts the median frost-free season at 190 days, and the season without a hard freeze (28°F) at 211 days.
A hard freeze (28°F) comes after April 2 in half of springs and before October 31 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Robinson in zone 6b in ZIP code 62454, the nearest ZIP area.
Frost dates for every NOAA station in Illinois · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00117345; USDA 2023 Plant Hardiness Zone Map, ZIP listings: PRISM Group, Oregon State University, https://prism.oregonstate.edu, accessed October 8, 2026. 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 Robinson?
In a normal year in Robinson, 40 days a year reach 90°F (1 of them 100°F or more), 114 nights fall to 32°F or colder and 99 days bring measurable precipitation.
- Days at 90°F or more
- 40a normal year
- Days at 100°F or more
- 1a normal year
- Nights at 32°F or colder
- 114a normal year
- Days that stay below freezing
- 26high of 32°F or less
- Days with 0.01 inch of precipitation
- 99a normal year
The highest temperature in this station's record (since 1895) is 108°F, on July 22, 1901; the lowest is −20°F, on February 9, 1899.
The wettest calendar year on that record is 2013, with 57.36 in; the snowiest season is 2002–03, with 23.9 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00117345; records: ACIS (NOAA Regional Climate Centers), station USC00117345. Records use complete months only; a month missing more than three days is left out.
How sunny is Robinson?
Over a year 74% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Robinson, 4.0 kWh per square metre a day. August is the sunniest month (82%) and December the cloudiest (60%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 61% | 1.8 |
| February | 64% | 2.6 |
| March | 67% | 3.7 |
| April | 71% | 4.9 |
| May | 73% | 5.5 |
| June | 80% | 6.3 |
| July | 81% | 6.2 |
| August | 82% | 5.6 |
| September | 81% | 4.7 |
| October | 74% | 3.3 |
| November | 70% | 2.2 |
| December | 60% | 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 Robinson need?
A normal year in Robinson brings 5,170 heating degree days, 4% fewer than the median U.S. place (5,373), and 1,249 cooling degree days, 38% 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 3,872 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,128 | 0 |
| February | 903 | 0 |
| March | 694 | 3 |
| April | 339 | 17 |
| May | 112 | 112 |
| June | 8 | 279 |
| July | 1 | 359 |
| August | 3 | 299 |
| September | 55 | 151 |
| October | 308 | 29 |
| November | 643 | 1 |
| December | 976 | 0 |
| Year (annual) | 5,170 | 1,249 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00117345. 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 Robinson been warmer than normal lately?
2025 averaged 54.9°F, 0.8°F above the 1991-2020 normal of 54.1°F. 5 of the 5 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 55.1°F | +1.0°F | 44.78 |
| 2022 | 54.4°F | +0.3°F | 40.02 |
| 2023 | 56.7°F | +2.6°F | 35.37 |
| 2024 | 56.9°F | +2.8°F | 39.65 |
| 2025 | 54.9°F | +0.8°F | – |
Source: observed years: ACIS, station USC00117345. A year counts only with all twelve months complete.
How does Robinson's climate compare?
Robinson is warmer than 108 of the other 143 places with their own NOAA record in Illinois, and wetter than 118. Across the 7,247 U.S. stations with normals, its annual mean of 54.1°F is warmer than 57%.
In the Köppen classification computed from these normals, Robinson 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 Robinson share this climate record?
3 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.
- Oblong, IL1,349 people · 7 mi W
- Stoy, IL106 people · 3 mi W
- Annapolis, IL51 people · 10 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 Robinson's climate
What is the coldest month in Robinson?
January, with a normal high of 37°F and a normal low of 20°F. The warmest is July (87°F by day, 66°F at night).
Does it snow in Robinson?
Yes. NOAA publishes no 1991-2020 snowfall normal for Robinson's NOAA station; the nearest record that keeps one, Palestine (8 miles away), records 12 inches of snow in a normal year.
What is the rainiest month in Robinson?
April, with 5.17 in of precipitation in a normal year; the driest is February with 2.41 in.
What plant hardiness zone is Robinson in?
The USDA's 2023 map puts Robinson in zone 6b in ZIP code 62454, the nearest ZIP area.
How late can frost come in Robinson?
In half of years the last 32°F night comes after April 13; in one year in ten it comes after April 28. Waiting until April 28 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Illinois climateThe statewide normals and every place in the state
- Palestine, IL8 miles from this station, 55.1°F a year
- Lawrenceville, IL19 miles from this station, 55.7°F a year
- Newton, IL22 miles from this station, 54.5°F a year
- Casey, IL23 miles from this station, 54.1°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made