Hysham (25 mi SSE), Montana climate: Climate normals at a NOAA weather station
Hysham (25 mi SSE)'s normal year runs from 9°F January nights to 88°F July afternoons, with 14.9 inches of precipitation and 47 inches of snow a year. (NOAA 1991-2020 normals)
In metric: a yearly mean of 7.0°C, January lows of −13°C, July highs of 31°C, 378 mm of precipitation a year.
- NOAA stationHysham (25 mi SSE)
- Station IDUSC00244364
- Location45.94°N 107.14°W
- Elevation3,100 ft (945 m)
Normals describe a typical year at the station, not a forecast. The National Weather Service forecast for Hysham (25 mi SSE).
- Jan 34° 9°
- Feb 37° 12°
- Mar 48° 21°
- Apr 57° 30°
- May 66° 39°
- Jun 77° 47°
- Jul 88° 53°
- Aug 87° 51°
- Sep 76° 41°
- Oct 60° 29°
- Nov 46° 19°
- Dec 36° 10°
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 Hysham (25 mi SSE) each month?
July is the warmest month, with normal highs of 88°F; January the coldest, with normal lows of 9°F. The most precipitation falls in May (2.57 in), the least in December (0.45 in).
| Month | High | Low | Mean | Precip. | Snow | Wet days | 90°F days | Freezing nights | Daylight |
|---|---|---|---|---|---|---|---|---|---|
| January | 34°F | 9°F | 21.2°F | 0.61 | 10.4 | 7 | <1 | 31 | 9 h |
| February | 37°F | 12°F | 24.6°F | 0.60 | 8.0 | 6 | <1 | 27 | 10 h 20 min |
| March | 48°F | 21°F | 34.3°F | 0.90 | 8.4 | 7 | <1 | 28 | 11 h 50 min |
| April | 57°F | 30°F | 43.2°F | 1.59 | 4.6 | 8 | <1 | 19 | 13 h 30 min |
| May | 66°F | 39°F | 52.5°F | 2.57 | 0.5 | 10 | <1 | 8 | 14 h 50 min |
| June | 77°F | 47°F | 61.9°F | 2.36 | 0.0 | 9 | 3 | 1 | 15 h 40 min |
| July | 88°F | 53°F | 70.4°F | 1.52 | 0.0 | 6 | 15 | <1 | 15 h 30 min |
| August | 87°F | 51°F | 68.7°F | 0.87 | 0.0 | 5 | 15 | <1 | 14 h 10 min |
| September | 76°F | 41°F | 58.4°F | 1.38 | 0.1 | 5 | 5 | 4 | 12 h 40 min |
| October | 60°F | 29°F | 44.5°F | 1.41 | 3.3 | 7 | <1 | 19 | 11 h |
| November | 46°F | 19°F | 32.4°F | 0.64 | 5.5 | 6 | <1 | 28 | 9 h 30 min |
| December | 36°F | 10°F | 23.0°F | 0.45 | 6.6 | 5 | <1 | 31 | 8 h 40 min |
| Year (annual) | 59°F | 30°F | 44.6°F | 14.90 | 47.4 | 82 | 39 | 194 |
The same normals in °C and millimetres
| Month | High | Low | Mean | Precip. | Snow |
|---|---|---|---|---|---|
| January | 1°C | −13°C | −6.0°C | 15 mm | 26 cm |
| February | 3°C | −11°C | −4.1°C | 15 mm | 20 cm |
| March | 9°C | −6°C | 1.3°C | 23 mm | 21 cm |
| April | 14°C | −1°C | 6.2°C | 40 mm | 12 cm |
| May | 19°C | 4°C | 11.4°C | 65 mm | 1 cm |
| June | 25°C | 8°C | 16.6°C | 60 mm | 0 cm |
| July | 31°C | 12°C | 21.3°C | 39 mm | 0 cm |
| August | 31°C | 10°C | 20.4°C | 22 mm | 0 cm |
| September | 24°C | 5°C | 14.7°C | 35 mm | 0 cm |
| October | 15°C | −1°C | 6.9°C | 36 mm | 8 cm |
| November | 8°C | −7°C | 0.2°C | 16 mm | 14 cm |
| December | 2°C | −12°C | −5.0°C | 11 mm | 17 cm |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00244364; 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 Hysham (25 mi SSE)?
Normal highs sit between 65°F and 85°F in May, June and September. Of those, September has the fewest days with rain (5).
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 USC00244364.
When is the last frost at Hysham (25 mi SSE)?
In Hysham (25 mi SSE), the last spring frost (32°F) comes after May 26 in half of years and after June 13 in one year in ten; the first autumn frost comes before September 16 in half of years and before September 1 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 261 year in 10 after June 13; 9 in 10 after May 12
- First autumn frost, half of years before
- September 161 year in 10 before September 1; 9 in 10 before October 1
NOAA puts the median frost-free season at 111 days, and the season without a hard freeze (28°F) at 136 days.
A hard freeze (28°F) comes after May 14 in half of springs and before September 27 in half of autumns.
The USDA's 2023 Plant Hardiness Zone Map puts Hysham (25 mi SSE) in zone 4b in ZIP code 59010, the nearest ZIP area.
Frost dates for every NOAA station in Montana · Frost dates by ZIP code
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities), station USC00244364; 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 at Hysham (25 mi SSE)?
In a normal year in Hysham (25 mi SSE), 39 days a year reach 90°F (6 of them 100°F or more), 194 nights fall to 32°F or colder and 82 days bring measurable precipitation.
- Days at 90°F or more
- 39a normal year
- Days at 100°F or more
- 6a normal year
- Nights at 32°F or colder
- 194a normal year
- Days that stay below freezing
- 42high of 32°F or less
- Days with 0.01 inch of precipitation
- 82a normal year
- Days with 1 inch of snow or more
- 19a normal year
The highest temperature in this station's record (since 1951) is 113°F, on July 15, 2002; the lowest is −50°F, on December 22, 1989.
The wettest calendar year on that record is 2016, with 21.46 in; the snowiest season is 1993–94, with 97.8 inches.
Source: NOAA NCEI 1991-2020 annual normals, station USC00244364; records: ACIS (NOAA Regional Climate Centers), station USC00244364. Records use complete months only; a month missing more than three days is left out.
How sunny is it at Hysham (25 mi SSE)?
Over a year 78% of the sunlight that would reach the ground under clear skies gets through the clouds at Hysham (25 mi SSE), 4.2 kWh per square metre a day. July is the sunniest month (89%) and April the cloudiest (70%).
| Month | Share of clear-sky sunshine | Sunshine, kWh/m² a day |
|---|---|---|
| January | 75% | 1.8 |
| February | 77% | 2.8 |
| March | 73% | 3.9 |
| April | 70% | 4.9 |
| May | 72% | 5.9 |
| June | 80% | 6.9 |
| July | 89% | 7.3 |
| August | 86% | 6.1 |
| September | 81% | 4.6 |
| October | 73% | 2.9 |
| November | 73% | 1.9 |
| December | 70% | 1.4 |
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 Hysham (25 mi SSE) record?
A normal year at Hysham (25 mi SSE) brings 7,860 heating degree days, 46% more than the median U.S. place (5,373), and 453 cooling degree days, 50% fewer than the median (908). Eight months need 300 or more heating degree days, a monthly mean of about 55°F or colder. For gardens and crops, NOAA counts 2,114 growing degree days a year above 50°F.
| Month | Heating | Cooling |
|---|---|---|
| January | 1,359 | 0 |
| February | 1,131 | 0 |
| March | 953 | 0 |
| April | 653 | 0 |
| May | 395 | 6 |
| June | 142 | 49 |
| July | 29 | 196 |
| August | 49 | 165 |
| September | 232 | 35 |
| October | 638 | 1 |
| November | 978 | 0 |
| December | 1,300 | 0 |
| Year (annual) | 7,860 | 453 |
Source: NOAA NCEI 1991-2020 monthly normals, station USC00244364. 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 Hysham (25 mi SSE) been warmer than normal?
2025 averaged 45.3°F, 0.7°F above the 1991-2020 normal of 44.6°F. 3 of the 4 complete years since 2022 ran warmer than the normal.
| Year | Mean | Against normal | Precip. | Snow |
|---|---|---|---|---|
| 2022 | 43.3°F | −1.3°F | 13.62 | 69.0 |
| 2023 | 45.4°F | +0.8°F | 14.98 | 32.0 |
| 2024 | 46.3°F | +1.7°F | 15.19 | 26.0 |
| 2025 | 45.3°F | +0.7°F | 18.58 | 59.0 |
Source: observed years: ACIS, station USC00244364. A year counts only with all twelve months complete.
How does Hysham (25 mi SSE)'s climate compare?
Hysham (25 mi SSE) is warmer than 83 of the 141 places with their own NOAA record in Montana, and wetter than 68. Across the 7,247 U.S. stations with normals, its annual mean of 44.6°F is warmer than 18%.
In the Köppen classification computed from these normals, Hysham (25 mi SSE) is Dfb: continental, no dry season, 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.
Questions about Hysham (25 mi SSE)'s climate
What is the coldest month at Hysham (25 mi SSE)?
January, with a normal high of 34°F and a normal low of 9°F. The warmest is July (88°F by day, 53°F at night).
Does it snow at Hysham (25 mi SSE)?
Yes: 47 inches in a normal year, falling on 25 days with 0.1 inch or more, the most in January (10.4 inches).
What is the rainiest month at Hysham (25 mi SSE)?
May, with 2.57 in of precipitation in a normal year; the driest is December with 0.45 in.
What plant hardiness zone is Hysham (25 mi SSE) in?
The USDA's 2023 map puts Hysham (25 mi SSE) in zone 4b in ZIP code 59010, the nearest ZIP area.
How late can frost come at Hysham (25 mi SSE)?
In half of years the last 32°F night comes after May 26; in one year in ten it comes after June 13. Waiting until June 13 leaves about a one-in-ten chance of a later frost.
Nearby and next
- Montana climateThe statewide normals and every place in the state
- Colstrip, MT24 miles from this station, 46.1°F a year
- Hysham, MT25 miles from this station, 47.2°F a year
- Hardin, MT27 miles from this station, 47.7°F a year
- Busby, MT29 miles from this station, 45.0°F a year
- Compare two placesMonth by month, side by side
Download these normals (CSV) · JSON · How these figures are made