Sterling, Colorado climate: Normal weather by month, frost dates and records
Sterling's normal year runs from 16°F December nights to 91°F July afternoons, with 15.2 inches of precipitation a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 10.8°C, December lows of −9°C, July highs of 33°C, 387 mm of precipitation a year.
- NOAA stationSterling
- Station IDUSC00057950
- Location40.63°N 103.21°W
- Elevation3,974 ft (1,211 m)
- Population13,114
On October 23, the normal high in Sterling is 63°F and the normal low 33°F, and the chance of measurable rain or snow is 12%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Sterling.
- Jan 42° 16°
- Feb 46° 19°
- Mar 57° 27°
- Apr 64° 35°
- May 73° 46°
- Jun 85° 57°
- Jul 91° 62°
- Aug 89° 60°
- Sep 81° 49°
- Oct 66° 35°
- Nov 53° 24°
- Dec 42° 16°
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 Sterling each month?
July is the warmest month, with normal highs of 91°F; December the coldest, with normal lows of 16°F. The most precipitation falls in July (2.67 in), the least in January (0.33 in).
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 42°F | 16°F | 28.9°F | 0.33 | 2 | <1 | 31 | 9 h 30 min |
| February | 46°F | 19°F | 32.1°F | 0.54 | 2 | <1 | 27 | 10 h 40 min |
| March | 57°F | 27°F | 41.7°F | 0.77 | 3 | <1 | 24 | 11 h 50 min |
| April | 64°F | 35°F | 49.5°F | 1.32 | 5 | <1 | 12 | 13 h 10 min |
| May | 73°F | 46°F | 59.5°F | 2.24 | 8 | 3 | 1 | 14 h 20 min |
| June | 85°F | 57°F | 70.8°F | 2.20 | 8 | 10 | <1 | 15 h |
| July | 91°F | 62°F | 76.7°F | 2.67 | 8 | 19 | <1 | 14 h 50 min |
| August | 89°F | 60°F | 74.1°F | 1.52 | 7 | 16 | <1 | 13 h 50 min |
| September | 81°F | 49°F | 65.1°F | 1.63 | 5 | 7 | 1 | 12 h 30 min |
| October | 66°F | 35°F | 50.8°F | 1.22 | 4 | <1 | 11 | 11 h 10 min |
| November | 53°F | 24°F | 38.7°F | 0.45 | 3 | <1 | 26 | 10 h |
| December | 42°F | 16°F | 28.6°F | 0.35 | 3 | <1 | 31 | 9 h 20 min |
| Year (annual) | 66°F | 37°F | 51.4°F | 15.24 | 57 | 56 | 164 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | 6°C | −9°C | −1.7°C | 8 mm |
| February | 8°C | −7°C | 0.1°C | 14 mm |
| March | 14°C | −3°C | 5.4°C | 20 mm |
| April | 18°C | 2°C | 9.7°C | 34 mm |
| May | 23°C | 8°C | 15.3°C | 57 mm |
| June | 29°C | 14°C | 21.6°C | 56 mm |
| July | 33°C | 17°C | 24.8°C | 68 mm |
| August | 31°C | 15°C | 23.4°C | 39 mm |
| September | 27°C | 9°C | 18.4°C | 41 mm |
| October | 19°C | 2°C | 10.4°C | 31 mm |
| November | 12°C | −4°C | 3.7°C | 11 mm |
| December | 5°C | −9°C | −1.9°C | 9 mm |
NOAA publishes no 1991-2020 snowfall normal for this station. The nearest record that keeps one, Leroy (5 mi WSW) (14 miles away), gets 37 inches of snow in a normal year; elevation and distance can change that.
Source: NOAA NCEI 1991-2020 monthly normals, station USC00057950; 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 Sterling?
Normal highs sit between 65°F and 85°F in May, June, September and October. Of those, October has the fewest days with rain (4).
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 USC00057950.
When is the last frost in Sterling?
In Sterling, the last spring frost (32°F) comes after April 30 in half of years and after May 12 in one year in ten; the first autumn frost comes before October 9 in half of years and before September 28 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 301 year in 10 after May 12; 9 in 10 after April 16
- First autumn frost, half of years before
- October 91 year in 10 before September 28; 9 in 10 before October 20
NOAA puts the median frost-free season at 161 days, and the season without a hard freeze (28°F) at 180 days.
A hard freeze (28°F) comes after April 18 in half of springs and before October 18 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Sterling in zone 5b in ZIP code 80751, the nearest ZIP area.
Frost dates for every NOAA station in Colorado · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00057950; 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 Sterling?
In a normal year in Sterling, 56 days a year reach 90°F (8 of them 100°F or more), 164 nights fall to 32°F or colder and 57 days bring measurable precipitation.
- Days at 90°F or more
- 56a normal year
- Days at 100°F or more
- 8a normal year
- Nights at 32°F or colder
- 164a normal year
- Days that stay below freezing
- 22high of 32°F or less
- Days with 0.01 inch of precipitation
- 57a normal year
The highest temperature in this station's record (since 1909) is 110°F, on June 28, 1990; the lowest is −35°F, on December 22, 1989.
The wettest calendar year on that record is 1915, with 22.25 in; the snowiest season is 1985–86, with 64.1 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00057950; records: ACIS (NOAA Regional Climate Centers), station USC00057950. Records use complete months only; a month missing more than three days is left out.
How sunny is Sterling?
Over a year 81% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Sterling, 4.8 kWh per square metre a day. August is the sunniest month (87%) and February the cloudiest (75%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 79% | 2.5 |
| February | 75% | 3.3 |
| March | 77% | 4.6 |
| April | 76% | 5.6 |
| May | 77% | 6.4 |
| June | 85% | 7.4 |
| July | 87% | 7.2 |
| August | 87% | 6.4 |
| September | 86% | 5.3 |
| October | 81% | 3.8 |
| November | 80% | 2.7 |
| December | 76% | 2.1 |
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 Sterling need?
A normal year in Sterling brings 5,938 heating degree days, 11% more than the median U.S. place (5,373), and 1,003 cooling degree days, 11% 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 3,250 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,121 | 0 |
| February | 922 | 0 |
| March | 723 | 0 |
| April | 467 | 2 |
| May | 208 | 36 |
| June | 31 | 205 |
| July | 3 | 366 |
| August | 7 | 289 |
| September | 99 | 103 |
| October | 445 | 3 |
| November | 788 | 0 |
| December | 1,127 | 0 |
| Year (annual) | 5,938 | 1,003 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00057950. 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.
How does Sterling's climate compare?
Sterling is warmer than 98 of the other 124 places with their own NOAA record in Colorado, and wetter than 57. Across the 7,247 U.S. stations with normals, its annual mean of 51.4°F is warmer than 47%.
In the Köppen classification computed from these normals, Sterling is BSk: cold semi-arid steppe. 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 Sterling share this climate record?
4 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.
- Merino, CO278 people · 13 mi SW
- Iliff, CO240 people · 12 mi NE
- Atwood, CO188 people · 6 mi SW
- Padroni, CO23 people · 11 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 Sterling's climate
What is the coldest month in Sterling?
December, with a normal high of 42°F and a normal low of 16°F. The warmest is July (91°F by day, 62°F at night).
Does it snow in Sterling?
Yes. NOAA publishes no 1991-2020 snowfall normal for Sterling's NOAA station; the nearest record that keeps one, Leroy (5 mi WSW) (14 miles away), records 37 inches of snow in a normal year.
What is the rainiest month in Sterling?
July, with 2.67 in of precipitation in a normal year; the driest is January with 0.33 in.
What plant hardiness zone is Sterling in?
The USDA's 2023 map puts Sterling in zone 5b in ZIP code 80751, the nearest ZIP area.
How late can frost come in Sterling?
In half of years the last 32°F night comes after April 30; in one year in ten it comes after May 12. Waiting until May 12 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Colorado climateThe statewide normals and every place in the state
- Leroy (5 mi WSW), CO14 miles from this station, 48.8°F a year
- Fleming, CO19 miles from this station, 50.8°F a year
- Crook, CO27 miles from this station, 50.5°F a year
- Akron, CO32 miles from this station, 50.2°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made