Bonny Dam (2 mi NE), Colorado climate: Climate normals at a NOAA weather station
Bonny Dam (2 mi NE)'s normal year runs from 17°F January nights to 91°F July afternoons, with 18.0 inches of precipitation and 24 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 10.9°C, January lows of −8°C, July highs of 33°C, 456 mm of precipitation a year.
- NOAA stationBonny Dam (2 mi NE)
- Station IDUSC00050834
- Location39.66°N 102.12°W
- Elevation3,717 ft (1,133 m)
On October 23, the normal high in Bonny Dam (2 mi NE) is 64°F and the normal low 34°F, and the chance of measurable rain or snow is 11%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Bonny Dam (2 mi NE).
- Jan 43° 17°
- Feb 46° 19°
- Mar 56° 27°
- Apr 64° 35°
- May 73° 45°
- Jun 86° 56°
- Jul 91° 62°
- Aug 88° 59°
- Sep 80° 50°
- Oct 67° 37°
- Nov 54° 26°
- Dec 44° 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 at Bonny Dam (2 mi NE) each month?
July is the warmest month, with normal highs of 91°F; January the coldest, with normal lows of 17°F. The most precipitation falls in July (3.20 in), the least in January (0.37 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 43°F | 17°F | 30.0°F | 0.37 | 4.6 | 2 | <1 | 30 | 9 h 40 min |
| February | 46°F | 19°F | 32.3°F | 0.43 | 5.3 | 3 | <1 | 27 | 10 h 40 min |
| March | 56°F | 27°F | 41.2°F | 0.89 | 3.1 | 3 | <1 | 23 | 11 h 50 min |
| April | 64°F | 35°F | 49.4°F | 1.75 | 2.5 | 6 | <1 | 11 | 13 h 10 min |
| May | 73°F | 45°F | 59.3°F | 2.71 | 0.3 | 7 | 2 | 2 | 14 h 20 min |
| June | 86°F | 56°F | 70.9°F | 2.64 | 0.0 | 7 | 10 | <1 | 15 h |
| July | 91°F | 62°F | 76.1°F | 3.20 | 0.0 | 7 | 19 | <1 | 14 h 40 min |
| August | 88°F | 59°F | 73.9°F | 1.85 | 0.0 | 6 | 16 | <1 | 13 h 50 min |
| September | 80°F | 50°F | 65.3°F | 1.78 | 0.3 | 4 | 6 | 1 | 12 h 30 min |
| October | 67°F | 37°F | 52.0°F | 1.26 | 1.8 | 4 | 1 | 8 | 11 h 10 min |
| November | 54°F | 26°F | 39.7°F | 0.56 | 1.9 | 2 | <1 | 23 | 10 h |
| December | 44°F | 18°F | 30.6°F | 0.52 | 4.3 | 3 | <1 | 30 | 9 h 20 min |
| Year (annual) | 66°F | 38°F | 51.7°F | 17.96 | 24.1 | 54 | 54 | 154 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | 6°C | −8°C | −1.1°C | 9 mm | 12 cm |
| February | 8°C | −7°C | 0.2°C | 11 mm | 13 cm |
| March | 13°C | −3°C | 5.1°C | 23 mm | 8 cm |
| April | 18°C | 1°C | 9.7°C | 44 mm | 6 cm |
| May | 23°C | 7°C | 15.2°C | 69 mm | 1 cm |
| June | 30°C | 13°C | 21.6°C | 67 mm | 0 cm |
| July | 33°C | 16°C | 24.5°C | 81 mm | 0 cm |
| August | 31°C | 15°C | 23.3°C | 47 mm | 0 cm |
| September | 27°C | 10°C | 18.5°C | 45 mm | 1 cm |
| October | 19°C | 3°C | 11.1°C | 32 mm | 5 cm |
| November | 12°C | −4°C | 4.3°C | 14 mm | 5 cm |
| December | 6°C | −8°C | −0.8°C | 13 mm | 11 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00050834; 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.
Which months are mildest at Bonny Dam (2 mi NE)?
Normal highs sit between 65°F and 85°F in May, 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 USC00050834.
When is the last frost at Bonny Dam (2 mi NE)?
In Bonny Dam (2 mi NE), the last spring frost (32°F) comes after May 5 in half of years and after May 19 in one year in ten; the first autumn frost comes before October 10 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
- May 51 year in 10 after May 19; 9 in 10 after April 21
- First autumn frost, half of years before
- October 101 year in 10 before September 28; 9 in 10 before October 21
NOAA puts the median frost-free season at 155 days, and the season without a hard freeze (28°F) at 173 days.
A hard freeze (28°F) comes after April 25 in half of springs and before October 18 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Bonny Dam (2 mi NE) in zone 6a in ZIP code 80735, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, the station is in zone 6a: the coldest night of a typical year reaches −8°F (18 complete years).
Frost dates for every NOAA station in Colorado · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00050834; 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 at Bonny Dam (2 mi NE)?
In a normal year in Bonny Dam (2 mi NE), 54 days a year reach 90°F (8 of them 100°F or more), 154 nights fall to 32°F or colder and 54 days bring measurable precipitation.
- Days at 90°F or more
- 54a normal year
- Days at 100°F or more
- 8a normal year
- Nights at 32°F or colder
- 154a normal year
- Days that stay below freezing
- 24high of 32°F or less
- Days with 0.01 inch of precipitation
- 54a normal year
- Days with 1 inch of snow or more
- 9a normal year
The highest temperature in this station's record (since 1949) is 109°F, on June 27, 2012; the lowest is −30°F, on January 18, 1984.
The wettest calendar year on that record is 1991, with 25.32 in; the snowiest season is 1959–60, with 65.4 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00050834; records: ACIS (NOAA Regional Climate Centers), station USC00050834. Records use complete months only; a month missing more than three days is left out.
How sunny is it at Bonny Dam (2 mi NE)?
Over a year 82% of the sunlight that would reach the ground under clear skies gets through the clouds at Bonny Dam (2 mi NE), 4.9 kWh per square metre a day. July is the sunniest month (88%) and February the cloudiest (75%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 79% | 2.6 |
| February | 75% | 3.4 |
| March | 78% | 4.7 |
| April | 77% | 5.7 |
| May | 79% | 6.6 |
| June | 86% | 7.4 |
| July | 88% | 7.3 |
| August | 88% | 6.5 |
| September | 86% | 5.3 |
| October | 81% | 3.9 |
| November | 81% | 2.8 |
| December | 78% | 2.2 |
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 many heating and cooling degree days does Bonny Dam (2 mi NE) record?
A normal year at Bonny Dam (2 mi NE) brings 5,807 heating degree days, 8% more than the median U.S. place (5,373), and 996 cooling degree days, 10% 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 3,276 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,087 | 0 |
| February | 915 | 0 |
| March | 736 | 0 |
| April | 472 | 3 |
| May | 219 | 40 |
| June | 29 | 206 |
| July | 4 | 348 |
| August | 8 | 282 |
| September | 101 | 109 |
| October | 412 | 7 |
| November | 758 | 0 |
| December | 1,066 | 0 |
| Year (annual) | 5,807 | 996 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00050834. 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.
Have recent years at Bonny Dam (2 mi NE) been warmer than normal?
2023 averaged 50.9°F, 0.8°F below the 1991-2020 normal of 51.7°F. 0 of the 2 complete years since 2022 ran warmer than the normal.
| Year | Mean | Against normal | Precip. | Snow |
|---|---|---|---|---|
| 2022 | 51.0°F | −0.7°F | – | – |
| 2023 | 50.9°F | −0.8°F | – | – |
Over 37 complete years from 1952 to 2023, the station's annual mean temperature rose at a fitted 2.9°F per century (+0.16°C per decade). A fitted rate summarizes the whole record; single years swing well above and below it.
Source: observed years: ACIS, station USC00050834; trend: NOAA GHCN-Monthly v4. A year counts only with all twelve months complete.
How does Bonny Dam (2 mi NE)'s climate compare?
Bonny Dam (2 mi NE) is warmer than 103 of the 125 places with their own NOAA record in Colorado, and wetter than 92. Across the 7,247 U.S. stations with normals, its annual mean of 51.7°F is warmer than 48%.
In the Köppen classification computed from these normals, Bonny Dam (2 mi NE) 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.
Questions about Bonny Dam (2 mi NE)'s climate
What is the coldest month at Bonny Dam (2 mi NE)?
January, with a normal high of 43°F and a normal low of 17°F. The warmest is July (91°F by day, 62°F at night).
Does it snow at Bonny Dam (2 mi NE)?
Yes: 24 inches in a normal year, falling on 11 days with 0.1 inch or more, the most in February (5.3 inches).
What is the rainiest month at Bonny Dam (2 mi NE)?
July, with 3.20 in of precipitation in a normal year; the driest is January with 0.37 in.
What plant hardiness zone is Bonny Dam (2 mi NE) in?
The USDA's 2023 map puts Bonny Dam (2 mi NE) in zone 6a in ZIP code 80735, the nearest ZIP area. By the same method at the station, the coldest night of a typical year reaches −8°F (18 years, 1991-2020): zone 6a.
How late can frost come at Bonny Dam (2 mi NE)?
In half of years the last 32°F night comes after May 5; in one year in ten it comes after May 19. Waiting until May 19 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Colorado climateThe statewide normals and every place in the state
- Idalia, CO10 miles from this station, 50.5°F a year
- St. Francis, KS18 miles from this station, 52.0°F a year
- Haigler, NE27 miles from this station, 51.2°F a year
- Wray, CO30 miles from this station, 51.2°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made