Opheim (10 mi N), Montana climate: Climate normals at a NOAA weather station
Opheim (10 mi N)'s normal year runs from 1°F January nights to 81°F July afternoons, with 14.4 inches of precipitation and 33 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 3.9°C, January lows of −17°C, July highs of 27°C, 367 mm of precipitation a year.
- NOAA stationOpheim (10 mi N)
- Station IDUSC00246236
- Location49.00°N 106.38°W
- Elevation2,878 ft (877 m)
On October 22, the normal high in Opheim (10 mi N) is 51°F and the normal low 26°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 Opheim (10 mi N).
- Jan 22° 1°
- Feb 26° 4°
- Mar 38° 15°
- Apr 54° 26°
- May 65° 36°
- Jun 73° 46°
- Jul 81° 50°
- Aug 81° 49°
- Sep 70° 39°
- Oct 54° 28°
- Nov 37° 15°
- Dec 25° 4°
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 Opheim (10 mi N) each month?
July is the warmest month, with normal highs of 81°F; January the coldest, with normal lows of 1°F. The most precipitation falls in June (3.70 in), the least in January (0.27 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 22°F | 1°F | 11.2°F | 0.27 | 4.5 | 3 | <1 | 31 | 8 h 40 min |
| February | 26°F | 4°F | 14.8°F | 0.37 | 6.2 | 3 | <1 | 28 | 10 h 10 min |
| March | 38°F | 15°F | 26.5°F | 0.43 | 5.1 | 3 | <1 | 29 | 11 h 50 min |
| April | 54°F | 26°F | 40.0°F | 0.91 | 2.5 | 5 | <1 | 23 | 13 h 40 min |
| May | 65°F | 36°F | 50.8°F | 2.09 | 0.9 | 7 | <1 | 11 | 15 h 10 min |
| June | 73°F | 46°F | 59.4°F | 3.70 | 0.0 | 11 | 1 | 1 | 16 h 10 min |
| July | 81°F | 50°F | 65.7°F | 2.25 | 0.0 | 7 | 4 | <1 | 15 h 50 min |
| August | 81°F | 49°F | 64.9°F | 1.57 | 0.0 | 6 | 6 | 1 | 14 h 30 min |
| September | 70°F | 39°F | 54.6°F | 1.39 | 0.2 | 6 | 1 | 7 | 12 h 40 min |
| October | 54°F | 28°F | 41.1°F | 0.82 | 1.2 | 4 | <1 | 22 | 10 h 50 min |
| November | 37°F | 15°F | 26.2°F | 0.36 | 5.3 | 3 | <1 | 28 | 9 h 10 min |
| December | 25°F | 4°F | 14.4°F | 0.27 | 7.1 | 3 | <1 | 31 | 8 h 20 min |
| Year (annual) | 52°F | 26°F | 39.1°F | 14.43 | 33.0 | 61 | 12 | 210 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | −6°C | −17°C | −11.6°C | 7 mm | 11 cm |
| February | −4°C | −16°C | −9.6°C | 9 mm | 16 cm |
| March | 3°C | −9°C | −3.1°C | 11 mm | 13 cm |
| April | 12°C | −3°C | 4.4°C | 23 mm | 6 cm |
| May | 19°C | 2°C | 10.4°C | 53 mm | 2 cm |
| June | 23°C | 8°C | 15.2°C | 94 mm | 0 cm |
| July | 27°C | 10°C | 18.7°C | 57 mm | 0 cm |
| August | 27°C | 9°C | 18.3°C | 40 mm | 0 cm |
| September | 21°C | 4°C | 12.6°C | 35 mm | 1 cm |
| October | 12°C | −2°C | 5.1°C | 21 mm | 3 cm |
| November | 3°C | −9°C | −3.2°C | 9 mm | 13 cm |
| December | −4°C | −15°C | −9.8°C | 7 mm | 18 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00246236; 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 Opheim (10 mi N)?
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 (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 USC00246236.
When is the last frost at Opheim (10 mi N)?
In Opheim (10 mi N), the last spring frost (32°F) comes after June 1 in half of years and after June 18 in one year in ten; the first autumn frost comes before September 7 in half of years and before August 24 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
- June 11 year in 10 after June 18; 9 in 10 after May 20
- First autumn frost, half of years before
- September 71 year in 10 before August 24; 9 in 10 before September 21
NOAA puts the median frost-free season at 99 days, and the season without a hard freeze (28°F) at 119 days.
A hard freeze (28°F) comes after May 21 in half of springs and before September 19 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Opheim (10 mi N) in zone 3b in ZIP code 59240, 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 3a: the coldest night of a typical year reaches −35°F (15 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 Montana · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00246236; 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 Opheim (10 mi N)?
In a normal year in Opheim (10 mi N), 12 days a year reach 90°F, 210 nights fall to 32°F or colder and 61 days bring measurable precipitation.
- Days at 90°F or more
- 12a normal year
- Days at 100°F or more
- fewer than 1a normal year
- Nights at 32°F or colder
- 210a normal year
- Days that stay below freezing
- 83high of 32°F or less
- Days with 0.01 inch of precipitation
- 61a normal year
- Days with 1 inch of snow or more
- 12a normal year
The highest temperature in this station's record (since 1959) is 105°F, on June 6, 1988; the lowest is −51°F, on February 28, 1962.
The wettest calendar year on that record is 1993, with 18.56 in; the snowiest season is 2016–17, with 67.0 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00246236; records: ACIS (NOAA Regional Climate Centers), station USC00246236. Records use complete months only; a month missing more than three days is left out.
How sunny is it at Opheim (10 mi N)?
Over a year 78% of the sunlight that would reach the ground under clear skies gets through the clouds at Opheim (10 mi N), 4.0 kWh per square metre a day. July is the sunniest month (86%) and December the cloudiest (68%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 75% | 1.5 |
| February | 78% | 2.6 |
| March | 75% | 3.8 |
| April | 73% | 4.9 |
| May | 75% | 6.0 |
| June | 77% | 6.5 |
| July | 86% | 6.9 |
| August | 85% | 5.7 |
| September | 79% | 4.2 |
| October | 75% | 2.7 |
| November | 72% | 1.6 |
| December | 68% | 1.1 |
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 many heating and cooling degree days does Opheim (10 mi N) record?
A normal year at Opheim (10 mi N) brings 9,603 heating degree days, 79% more than the median U.S. place (5,373), and 211 cooling degree days, 77% fewer than the median (908). Nine months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 1,599 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,668 | 0 |
| February | 1,406 | 0 |
| March | 1,194 | 0 |
| April | 750 | 0 |
| May | 445 | 3 |
| June | 189 | 21 |
| July | 67 | 89 |
| August | 86 | 84 |
| September | 325 | 13 |
| October | 743 | 0 |
| November | 1,164 | 0 |
| December | 1,567 | 0 |
| Year (annual) | 9,603 | 211 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00246236. 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 Opheim (10 mi N) been warmer than normal?
2025 averaged 40.6°F, 1.5°F above the 1991-2020 normal of 39.1°F. 2 of the 2 complete years since 2024 ran warmer than the normal.
| Year | Mean | Against normal | Precip. | Snow |
|---|---|---|---|---|
| 2024 | 41.3°F | +2.2°F | 11.61 | 38.6 |
| 2025 | 40.6°F | +1.5°F | 10.09 | 32.1 |
Over 31 complete years from 1960 to 2024, the station's annual mean temperature rose at a fitted 7.6°F per century (+0.42°C per decade). A fitted rate summarizes the whole record; single years swing well above and below it.
Source: observed years: ACIS, station USC00246236; trend: NOAA GHCN-Monthly v4. A year counts only with all twelve months complete.
How does Opheim (10 mi N)'s climate compare?
Opheim (10 mi N) is warmer than 8 of the 141 places with their own NOAA record in Montana, and wetter than 55. Across the 7,247 U.S. stations with normals, its annual mean of 39.1°F is warmer than 4%.
In the Köppen classification computed from these normals, Opheim (10 mi N) is Dwb: continental, dry-winter, warm 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 Opheim (10 mi N) share this climate record?
Opheim has no NOAA station with 1991-2020 normals of its 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.
- Opheim, MT73 people · 10 mi S
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 Opheim (10 mi N)'s climate
What is the coldest month at Opheim (10 mi N)?
January, with a normal high of 22°F and a normal low of 1°F. The warmest is July (81°F by day, 50°F at night).
Does it snow at Opheim (10 mi N)?
Yes: 33 inches in a normal year, falling on 15 days with 0.1 inch or more, the most in December (7.1 inches).
What is the rainiest month at Opheim (10 mi N)?
June, with 3.70 in of precipitation in a normal year; the driest is January with 0.27 in.
What plant hardiness zone is Opheim (10 mi N) in?
The USDA's 2023 map puts Opheim (10 mi N) in zone 3b in ZIP code 59240, the nearest ZIP area. By the same method at the station, the coldest night of a typical year reaches −35°F (15 years, 1991-2020): zone 3a.
How late can frost come at Opheim (10 mi N)?
In half of years the last 32°F night comes after June 1; in one year in ten it comes after June 18. Waiting until June 18 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Montana climateThe statewide normals and every place in the state
- Opheim (12 mi SSE), MT21 miles from this station, 35.5°F a year
- St. Marie, MT41 miles from this station, 43.0°F a year
- Scobey, MT43 miles from this station, 40.2°F a year
- Glasgow, MT55 miles from this station, 43.9°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made