30-year climate normals

Silver Bow County Climate and Weather Averages

Hottest month — July

81.3°

average daily high. The coldest month is December, averaging a low of 7.2°F.

Silver Bow County gets 12.76" of precipitation a year, and 45% 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	32.1°	7.9°	0.42"
February	34.6°	9.8°	0.43"
March	43.7°	19.4°	0.64"
April	51.1°	26.4°	1.33"
May	61.0°	34.3°	2.02"
June	70.0°	41.1°	2.45"
July	81.3°	45.9°	1.20"
August	79.8°	43.9°	1.28"
September	69.1°	36.5°	1.07"
October	54.3°	26.8°	0.84"
November	40.2°	15.5°	0.60"
December	30.7°	7.2°	0.48"

Rainfall by month

Silver Bow County has a distinct wet season. 45% of the year's precipitation arrives in Apr, May, Jun.

January 0.42"

February 0.43"

March 0.64"

April 1.33"

May 2.02"

June 2.45"

July 1.20"

August 1.28"

September 1.07"

October 0.84"

November 0.60"

December 0.48"

Annual total 12.76"

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 83

Heating degree days How much heating the climate demands 9,129

Approximate annual cooling cost At 14.67¢/kWh, Montana average $12

Approximate annual electric heating cost Lower where heating is gas rather than electric $469

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 Silver Bow County, where electricity is one line of eight.

Common questions

What is the weather like in Silver Bow County?

Silver Bow County averages a high of 81.3°F in July and a low of 7.2°F in December. Annual precipitation is 12.76 inches, with essentially no snow.

When is the rainy season in Silver Bow County?

The wettest stretch is Apr, May, Jun, which accounts for 45% 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 Silver Bow County?

The average daily high in July, the hottest month, is 81.3°F. That drives 83 cooling degree days a year, which is what your air conditioning has to work against.

Does it snow in Silver Bow County?

Effectively no. Measurable snowfall is rare in Silver Bow County.

Sources

Temperature, precipitation and snowfall normals — NOAA National Centers for Environmental Information, 1991–2020 Monthly Climate Normals, station BUTTE BERT MOONEY AP, MT US (USW00024135), 9 miles from the county centroid.
Heating and cooling degree days — NOAA, same station and period.
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.