30-year climate normals

Grant County Climate and Weather Averages

Hottest month — July

81.0°

average daily high. The coldest month is January, averaging a low of 3.5°F.

Grant County gets 25.43" of precipitation a year, and 43% of it falls in Jun, Jul, Aug.

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	20.9°	3.5°	0.71"
February	25.6°	6.7°	0.70"
March	37.8°	19.0°	1.18"
April	53.8°	31.8°	2.41"
May	67.0°	44.5°	2.89"
June	76.9°	56.2°	3.92"
July	81.0°	60.2°	3.80"
August	79.1°	57.3°	3.21"
September	71.8°	48.0°	2.60"
October	57.9°	34.7°	2.31"
November	40.8°	21.9°	0.93"
December	26.5°	9.7°	0.77"

Rainfall by month

Precipitation is spread fairly evenly through the year here, with 43% falling in the wettest three months (Jun, Jul, Aug).

January 0.71"

February 0.70"

March 1.18"

April 2.41"

May 2.89"

June 3.92"

July 3.80"

August 3.21"

September 2.60"

October 2.31"

November 0.93"

December 0.77"

Annual total 25.43"

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 483

Heating degree days How much heating the climate demands 8,452

Approximate annual cooling cost At 15.73¢/kWh, South Dakota average $76

Approximate annual electric heating cost Lower where heating is gas rather than electric $465

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 Grant County, where electricity is one line of eight.

Common questions

What is the weather like in Grant County?

Grant County averages a high of 81.0°F in July and a low of 3.5°F in January. Annual precipitation is 25.43 inches, with essentially no snow.

When is the rainy season in Grant County?

The wettest stretch is Jun, Jul, Aug, which accounts for 43% of the year's precipitation. Precipitation is relatively evenly distributed across the year.

How hot does it get in Grant County?

The average daily high in July, the hottest month, is 81.0°F. That drives 483 cooling degree days a year, which is what your air conditioning has to work against.

Does it snow in Grant County?

Effectively no. Measurable snowfall is rare in Grant County.

Sources

Temperature, precipitation and snowfall normals — NOAA National Centers for Environmental Information, 1991–2020 Monthly Climate Normals, station MILBANK, SD US (USC00395531), 8.2 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, South Dakota residential average.
Wet-season share is the wettest three consecutive months as a percentage of annual precipitation, calculated from the monthly normals.