30-year climate normals

Clay County Climate and Weather Averages

Hottest month — July

84.5°

average daily high. The coldest month is January, averaging a low of 8.1°F.

Clay County gets 26.83" of precipitation a year, and 44% of it falls in May, Jun, Jul.

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	25.8°	8.1°	0.25"
February	30.3°	12.6°	0.43"
March	43.6°	24.8°	1.44"
April	58.9°	35.5°	2.82"
May	70.9°	47.9°	3.83"
June	80.9°	58.7°	4.01"
July	84.5°	62.3°	3.84"
August	81.9°	59.2°	3.29"
September	75.8°	50.2°	3.21"
October	61.3°	37.4°	2.22"
November	44.6°	24.7°	1.07"
December	30.7°	13.6°	0.42"

Rainfall by month

Precipitation is spread fairly evenly through the year here, with 44% falling in the wettest three months (May, Jun, Jul).

January 0.25"

February 0.43"

March 1.44"

April 2.82"

May 3.83"

June 4.01"

July 3.84"

August 3.29"

September 3.21"

October 2.22"

November 1.07"

December 0.42"

Annual total 26.83"

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 774

Heating degree days How much heating the climate demands 7,353

Approximate annual cooling cost At 14.14¢/kWh, Iowa average $109

Approximate annual electric heating cost Lower where heating is gas rather than electric $364

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 Clay County, where electricity is one line of eight.

Common questions

What is the weather like in Clay County?

Clay County averages a high of 84.5°F in July and a low of 8.1°F in January. Annual precipitation is 26.83 inches, with essentially no snow.

When is the rainy season in Clay County?

The wettest stretch is May, Jun, Jul, which accounts for 44% of the year's precipitation. Precipitation is relatively evenly distributed across the year.

How hot does it get in Clay County?

The average daily high in July, the hottest month, is 84.5°F. That drives 774 cooling degree days a year, which is what your air conditioning has to work against.

Does it snow in Clay County?

Effectively no. Measurable snowfall is rare in Clay County.

Sources

Temperature, precipitation and snowfall normals — NOAA National Centers for Environmental Information, 1991–2020 Monthly Climate Normals, station SPENCER MUNI AP, IA US (USW00014972), 6.3 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, Iowa residential average.
Wet-season share is the wettest three consecutive months as a percentage of annual precipitation, calculated from the monthly normals.