Colo, Iowa climate: Normal weather by month, frost dates and records
Colo's normal year runs from 10°F January nights to 83°F July afternoons, with 36.5 inches of precipitation and 31 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 8.8°C, January lows of −12°C, July highs of 28°C, 926 mm of precipitation a year.
- NOAA stationColo
- Station IDUSC00131710
- Location42.02°N 93.32°W
- Elevation1,000 ft (305 m)
- From the centerunder 1 mile
- Population856
On October 23, the normal high in Colo is 59°F and the normal low 37°F, and the chance of measurable rain or snow is 22%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Colo.
- Jan 27° 10°
- Feb 31° 14°
- Mar 45° 26°
- Apr 59° 37°
- May 70° 49°
- Jun 80° 60°
- Jul 83° 63°
- Aug 81° 61°
- Sep 75° 52°
- Oct 62° 39°
- Nov 46° 27°
- Dec 32° 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 Colo each month?
July is the warmest month, with normal highs of 83°F; January the coldest, with normal lows of 10°F. The most precipitation falls in June (5.78 in), the least in January (0.95 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 27°F | 10°F | 18.4°F | 0.95 | 7.4 | 5 | <1 | 31 | 9 h 30 min |
| February | 31°F | 14°F | 22.6°F | 1.20 | 7.6 | 5 | <1 | 26 | 10 h 30 min |
| March | 45°F | 26°F | 35.3°F | 2.01 | 4.5 | 6 | <1 | 24 | 11 h 50 min |
| April | 59°F | 37°F | 48.1°F | 3.48 | 1.7 | 9 | <1 | 9 | 13 h 20 min |
| May | 70°F | 49°F | 59.8°F | 4.81 | 0.0 | 12 | <1 | 1 | 14 h 30 min |
| June | 80°F | 60°F | 70.0°F | 5.78 | 0.0 | 10 | 2 | <1 | 15 h 10 min |
| July | 83°F | 63°F | 73.2°F | 4.32 | 0.0 | 9 | 5 | <1 | 15 h |
| August | 81°F | 61°F | 71.1°F | 4.22 | 0.0 | 8 | 2 | <1 | 14 h |
| September | 75°F | 52°F | 63.4°F | 3.37 | 0.0 | 7 | 1 | 1 | 12 h 30 min |
| October | 62°F | 39°F | 50.6°F | 2.74 | 0.7 | 7 | <1 | 8 | 11 h 10 min |
| November | 46°F | 27°F | 36.5°F | 2.04 | 1.9 | 6 | <1 | 22 | 9 h 50 min |
| December | 32°F | 16°F | 24.1°F | 1.54 | 6.8 | 5 | <1 | 30 | 9 h 10 min |
| Year (annual) | 58°F | 38°F | 47.8°F | 36.46 | 30.6 | 87 | 11 | 151 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | −3°C | −12°C | −7.6°C | 24 mm | 19 cm |
| February | 0°C | −10°C | −5.2°C | 30 mm | 19 cm |
| March | 7°C | −4°C | 1.8°C | 51 mm | 11 cm |
| April | 15°C | 3°C | 8.9°C | 88 mm | 4 cm |
| May | 21°C | 10°C | 15.4°C | 122 mm | 0 cm |
| June | 27°C | 16°C | 21.1°C | 147 mm | 0 cm |
| July | 28°C | 17°C | 22.9°C | 110 mm | 0 cm |
| August | 27°C | 16°C | 21.7°C | 107 mm | 0 cm |
| September | 24°C | 11°C | 17.4°C | 86 mm | 0 cm |
| October | 17°C | 4°C | 10.3°C | 70 mm | 2 cm |
| November | 8°C | −3°C | 2.5°C | 52 mm | 5 cm |
| December | 0°C | −9°C | −4.4°C | 39 mm | 17 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00131710; 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 Colo?
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 (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 USC00131710.
When is the last frost in Colo?
In Colo, the last spring frost (32°F) comes after April 24 in half of years and after May 7 in one year in ten; the first autumn frost comes before October 12 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 241 year in 10 after May 7; 9 in 10 after April 9
- First autumn frost, half of years before
- October 121 year in 10 before September 28; 9 in 10 before October 26
NOAA puts the median frost-free season at 170 days, and the season without a hard freeze (28°F) at 191 days.
A hard freeze (28°F) comes after April 14 in half of springs and before October 23 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Colo in zone 5a in ZIP code 50056, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, Colo's NOAA station is in zone 5b: the coldest night of a typical year reaches −14°F (18 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 Iowa · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00131710; 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 Colo?
In a normal year in Colo, 11 days a year reach 90°F, 151 nights fall to 32°F or colder and 87 days bring measurable precipitation.
- Days at 90°F or more
- 11a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 151a normal year
- Days that stay below freezing
- 62high of 32°F or less
- Days with 0.01 inch of precipitation
- 87a normal year
- Days with 1 inch of snow or more
- 13a normal year
The highest temperature in this station's record (since 1964) is 104°F, on August 18, 1988; the lowest is −28°F, on January 16, 1977.
The wettest calendar year on that record is 1993, with 59.74 in; the snowiest season is 1981–82, with 49.5 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00131710; records: ACIS (NOAA Regional Climate Centers), station USC00131710. Records use complete months only; a month missing more than three days is left out.
How sunny is Colo?
Over a year 74% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Colo, 4.0 kWh per square metre a day. July is the sunniest month (82%) and December the cloudiest (66%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 69% | 1.9 |
| February | 75% | 3.0 |
| March | 70% | 3.8 |
| April | 69% | 4.8 |
| May | 71% | 5.6 |
| June | 76% | 6.2 |
| July | 82% | 6.4 |
| August | 80% | 5.5 |
| September | 79% | 4.4 |
| October | 72% | 3.0 |
| November | 71% | 2.1 |
| December | 66% | 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 Colo need?
A normal year in Colo brings 7,020 heating degree days, 31% more than the median U.S. place (5,373), and 780 cooling degree days, 14% 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 2,971 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,446 | 0 |
| February | 1,186 | 0 |
| March | 920 | 1 |
| April | 513 | 6 |
| May | 207 | 45 |
| June | 29 | 179 |
| July | 5 | 257 |
| August | 12 | 203 |
| September | 126 | 80 |
| October | 455 | 10 |
| November | 857 | 0 |
| December | 1,266 | 0 |
| Year (annual) | 7,020 | 780 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00131710. 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 Colo's climate compare?
Colo is warmer than 60 of the other 131 places with their own NOAA record in Iowa, and wetter than 61. Across the 7,247 U.S. stations with normals, its annual mean of 47.8°F is warmer than 31%.
In the Köppen classification computed from these normals, Colo 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 Colo share this climate record?
11 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.
- Nevada, IA7,082 people · 8 mi W
- State Center, IA1,403 people · 8 mi E
- Maxwell, IA862 people · 10 mi SW
- Melbourne, IA771 people · 12 mi SE
- Zearing, IA508 people · 10 mi N
- Collins, IA503 people · 8 mi S
- McCallsburg, IA356 people · 11 mi N
- Rhodes, IA269 people · 9 mi SE
- Clemons, IA135 people · 11 mi NE
- St. Anthony, IA77 people · 10 mi NE
- Garden City, IA67 people · 16 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 Colo's climate
What is the coldest month in Colo?
January, with a normal high of 27°F and a normal low of 10°F. The warmest is July (83°F by day, 63°F at night).
Does it snow in Colo?
Yes: 31 inches in a normal year, falling on 13 days with 0.1 inch or more, the most in February (7.6 inches).
What is the rainiest month in Colo?
June, with 5.78 in of precipitation in a normal year; the driest is January with 0.95 in.
What plant hardiness zone is Colo in?
The USDA's 2023 map puts Colo in zone 5a in ZIP code 50056, the nearest ZIP area. By the same method at Colo's NOAA station, the coldest night of a typical year reaches −14°F (18 years, 1991-2020): zone 5b.
How late can frost come in Colo?
In half of years the last 32°F night comes after April 24; in one year in ten it comes after May 7. Waiting until May 7 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Iowa climateThe statewide normals and every place in the state
- Ames, IA16 miles from this station, 48.5°F a year
- Marshalltown, IA22 miles from this station, 47.7°F a year
- Newton, IA26 miles from this station, 48.6°F a year
- Ankeny, IA26 miles from this station, 49.5°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made