This weather has a price Keeping the median Custer County home comfortable runs roughly $526 a year in heating and cooling alone. See where it lands in the monthly bill

30-year climate normals

Custer County Climate and Weather Averages

Hottest month: July

88.7°

average daily high. The coldest month is January, averaging a low of 8.9°F.

Custer County gets 12.88" of precipitation a year, and 53% of it falls in Apr, May, Jun.

Temperature through the year

Each bar spans the average daily low to the average daily high for that month.

Month	Avg high	Avg low	Precip
January	30.1°	8.9°	0.28"
February	34.7°	12.5°	0.26"
March	46.8°	22.5°	0.55"
April	58.1°	32.9°	1.54"
May	68.1°	42.9°	2.73"
June	78.6°	52.5°	2.51"
July	88.7°	59.6°	1.51"
August	87.4°	57.6°	0.91"
September	75.6°	46.9°	1.07"
October	59.0°	33.8°	0.97"
November	44.3°	21.2°	0.33"
December	33.1°	11.7°	0.22"

Rainfall by month

Custer County has a distinct wet season. 53% of the year's precipitation arrives in Apr, May, Jun.

January 0.28"

February 0.26"

March 0.55"

April 1.54"

May 2.73"

June 2.51"

July 1.51"

August 0.91"

September 1.07"

October 0.97"

November 0.33"

December 0.22"

Annual total 12.88"

What this climate costs you

Degree days measure how hard a building has to work to stay comfortable. They are the reason two identical houses have very different power bills, and they are the link between the weather here and what you pay every month.

Cooling degree days How much air conditioning the climate demands 731

Heating degree days How much heating the climate demands 7,566

Approximate annual cooling cost At 15.57¢/kWh, Montana average $114

Approximate annual electric heating cost Lower where heating is gas rather than electric $412

These are rough planning figures from degree days and the state electricity price, not a bill estimate. House size, insulation and fuel type move them a lot. See the full cost of owning a home in Custer County, where electricity is one line of eight.

Common questions

What is the weather like in Custer County?

Custer County averages a high of 88.7°F in July and a low of 8.9°F in January. Annual precipitation is 12.88 inches, with essentially no snow.

When is the rainy season in Custer County?

The wettest stretch is Apr, May, Jun, which accounts for 53% of the year's precipitation. That is a pronounced wet season rather than rain spread evenly through the year.

How hot does it get in Custer County?

The average daily high in July, the hottest month, is 88.7°F. That drives 731 cooling degree days a year, which is what your air conditioning has to work against.

Does it snow in Custer County?

The weather station used for Custer County, MILES CITY F WILEY FLD, MT US, reports temperature and precipitation but not snowfall, so there is no snow normal to quote here. Precipitation that falls as snow is still counted in the 12.88 inches above, measured as melted water.

Sources

Temperature, precipitation and snowfall normals: NOAA National Centers for Environmental Information, 1991 to 2020 Monthly Climate Normals, station MILES CITY F WILEY FLD, MT US (USW00024037), 19.5 miles from the county centroid.
Heating and cooling degree days: NOAA, same station and period.
Annual figures on this page are the sum of that station's twelve monthly normals. NOAA also publishes a separately-computed annual normal, which can differ from the monthly sum by a few percent; we use the monthly series because the month-by-month breakdown above has to come from it.
Electricity price: US Energy Information Administration, Electric Power Monthly Table 5.6.A, Montana residential average.
Wet-season share is the wettest three consecutive months as a percentage of annual precipitation, calculated from the monthly normals.