Guymon, Oklahoma climate: Normal weather by month, frost dates and records
Guymon's normal year runs from 22°F January nights to 95°F July afternoons, with 17.8 inches of precipitation a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 14.2°C, January lows of −6°C, July highs of 35°C, 451 mm of precipitation a year.
- NOAA stationGuymon Municipal Airport
- Station IDUSW00003030
- Location36.68°N 101.51°W
- Elevation3,123 ft (952 m)
- Population12,397
On October 14, the normal high in Guymon is 74°F and the normal low 44°F, and the chance of measurable rain or snow is 18%.
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Guymon.
- Jan 51° 22°
- Feb 54° 24°
- Mar 63° 32°
- Apr 71° 41°
- May 81° 51°
- Jun 91° 62°
- Jul 95° 67°
- Aug 92° 65°
- Sep 85° 57°
- Oct 73° 43°
- Nov 61° 31°
- Dec 50° 23°
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 Guymon each month?
July is the warmest month, with normal highs of 95°F; January the coldest, with normal lows of 22°F. The most precipitation falls in June (2.88 in), the least in February (0.33 in).
| Month | High | Low | Mean | Precip. | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|
| January | 51°F | 22°F | 36.3°F | 0.41 | 3 | <1 | 28 | 9 h 50 min |
| February | 54°F | 24°F | 39.2°F | 0.33 | 4 | <1 | 24 | 10 h 50 min |
| March | 63°F | 32°F | 47.6°F | 1.11 | 5 | <1 | 16 | 11 h 50 min |
| April | 71°F | 41°F | 56.0°F | 1.49 | 6 | 2 | 5 | 13 h 10 min |
| May | 81°F | 51°F | 66.0°F | 2.25 | 7 | 8 | <1 | 14 h 10 min |
| June | 91°F | 62°F | 76.2°F | 2.88 | 8 | 18 | <1 | 14 h 40 min |
| July | 95°F | 67°F | 80.8°F | 2.39 | 9 | 25 | <1 | 14 h 30 min |
| August | 92°F | 65°F | 78.5°F | 2.58 | 9 | 22 | <1 | 13 h 40 min |
| September | 85°F | 57°F | 70.9°F | 1.36 | 7 | 12 | <1 | 12 h 30 min |
| October | 73°F | 43°F | 58.0°F | 1.75 | 6 | 3 | 4 | 11 h 20 min |
| November | 61°F | 31°F | 45.7°F | 0.51 | 3 | <1 | 17 | 10 h 10 min |
| December | 50°F | 23°F | 36.4°F | 0.69 | 4 | <1 | 28 | 9 h 40 min |
| Year (annual) | 72°F | 43°F | 57.6°F | 17.75 | 69 | 89 | 122 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. |
|---|---|---|---|---|
| January | 10°C | −6°C | 2.4°C | 10 mm |
| February | 12°C | −4°C | 4.0°C | 8 mm |
| March | 17°C | 0°C | 8.7°C | 28 mm |
| April | 22°C | 5°C | 13.3°C | 38 mm |
| May | 27°C | 11°C | 18.9°C | 57 mm |
| June | 33°C | 16°C | 24.6°C | 73 mm |
| July | 35°C | 19°C | 27.1°C | 61 mm |
| August | 33°C | 18°C | 25.8°C | 66 mm |
| September | 30°C | 14°C | 21.6°C | 35 mm |
| October | 23°C | 6°C | 14.4°C | 44 mm |
| November | 16°C | −1°C | 7.6°C | 13 mm |
| December | 10°C | −5°C | 2.4°C | 18 mm |
NOAA publishes no 1991-2020 snowfall normal for this station. The nearest record that keeps one, Goodwell Research Station (9 miles away), gets 3 inches of snow in a normal year; elevation and distance can change that.
Source: NOAA NCEI 1991-2020 monthly normals, station USW00003030; 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 Guymon?
Normal highs sit between 65°F and 85°F in April, May and October. Of those, October 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 USW00003030.
When is the last frost in Guymon?
In Guymon, the last spring frost (32°F) comes after April 18 in half of years and after May 1 in one year in ten; the first autumn frost comes before October 23 in half of years and before October 11 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 181 year in 10 after May 1; 9 in 10 after April 4
- First autumn frost, half of years before
- October 231 year in 10 before October 11; 9 in 10 before November 3
NOAA puts the median frost-free season at 188 days, and the season without a hard freeze (28°F) at 206 days.
A hard freeze (28°F) comes after April 8 in half of springs and before November 1 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Guymon in zone 6b in ZIP code 73942, the nearest ZIP area. By the map's own method, the average of each year's coldest night over 1991-2020, Guymon's NOAA station is in zone 7a: the coldest night of a typical year reaches 0°F (21 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 Oklahoma · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USW00003030; 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 Guymon?
In a normal year in Guymon, 89 days a year reach 90°F (22 of them 100°F or more), 122 nights fall to 32°F or colder and 69 days bring measurable precipitation.
- Days at 90°F or more
- 89a normal year
- Days at 100°F or more
- 22a normal year
- Nights at 32°F or colder
- 122a normal year
- Days that stay below freezing
- 10high of 32°F or less
- Days with 0.01 inch of precipitation
- 69a normal year
The highest temperature in this station's record (since 1998) is 113°F, on June 26, 2011; the lowest is −14°F, on February 15, 2021.
The wettest calendar year on that record is 2015, with 30.83 in; the snowiest season is 2009–10, with 29.6 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USW00003030; records: ACIS (NOAA Regional Climate Centers), station USW00003030. Records use complete months only; a month missing more than three days is left out.
How sunny is Guymon?
Over a year 85% of the sunlight that would reach the ground under clear skies gets through the clouds in the area around Guymon, 5.2 kWh per square metre a day. July is the sunniest month (90%) and February the cloudiest (78%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 81% | 2.9 |
| February | 78% | 3.7 |
| March | 81% | 5.0 |
| April | 82% | 6.2 |
| May | 84% | 7.0 |
| June | 89% | 7.6 |
| July | 90% | 7.4 |
| August | 88% | 6.5 |
| September | 88% | 5.5 |
| October | 83% | 4.2 |
| November | 84% | 3.2 |
| December | 80% | 2.6 |
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 Guymon need?
A normal year in Guymon brings 4,293 heating degree days, 20% fewer than the median U.S. place (5,373), and 1,640 cooling degree days, 81% more than the median (908). Five months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 4,437 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 890 | 0 |
| February | 721 | 1 |
| March | 545 | 4 |
| April | 289 | 19 |
| May | 90 | 121 |
| June | 4 | 338 |
| July | 0 | 488 |
| August | 1 | 418 |
| September | 35 | 213 |
| October | 252 | 37 |
| November | 582 | 1 |
| December | 885 | 0 |
| Year (annual) | 4,293 | 1,640 |
Source: NOAA NCEI 1991-2020 monthly normals, station USW00003030. 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 Guymon been warmer than normal lately?
2025 averaged 58.2°F, 0.6°F above the 1991-2020 normal of 57.6°F. 4 of the 4 complete years since 2021 ran warmer than the normal.
| Year | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 58.5°F | +0.9°F | 13.15 |
| 2022 | 58.8°F | +1.2°F | 9.68 |
| 2024 | 59.2°F | +1.6°F | 24.76 |
| 2025 | 58.2°F | +0.6°F | – |
Source: observed years: ACIS, station USW00003030. A year counts only with all twelve months complete.
How does Guymon's climate compare?
Guymon is warmer than 10 of the other 133 places with their own NOAA record in Oklahoma, and wetter than 0. Across the 7,247 U.S. stations with normals, its annual mean of 57.6°F is warmer than 68%.
In the Köppen classification computed from these normals, Guymon 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 Guymon's climate
What is the coldest month in Guymon?
January, with a normal high of 51°F and a normal low of 22°F. The warmest is July (95°F by day, 67°F at night).
Does it snow in Guymon?
Yes. NOAA publishes no 1991-2020 snowfall normal for Guymon's NOAA station; the nearest record that keeps one, Goodwell Research Station (9 miles away), records 3 inches of snow in a normal year.
What is the rainiest month in Guymon?
June, with 2.88 in of precipitation in a normal year; the driest is February with 0.33 in.
What plant hardiness zone is Guymon in?
The USDA's 2023 map puts Guymon in zone 6b in ZIP code 73942, the nearest ZIP area. By the same method at Guymon's NOAA station, the coldest night of a typical year reaches 0°F (21 years, 1991-2020): zone 7a.
How late can frost come in Guymon?
In half of years the last 32°F night comes after April 18; in one year in ten it comes after May 1. Waiting until May 1 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Oklahoma climateThe statewide normals and every place in the state
- Goodwell, OK7 miles from this station, 56.3°F a year
- Hooker, OK20 miles from this station, 57.2°F a year
- Gruver, TX29 miles from this station, 56.3°F a year
- Elkhart, KS31 miles from this station, 56.0°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made