30-year climate normals

Washington County Climate and Weather Averages

Hottest month — July

79.3°

average daily high. The coldest month is January, averaging a low of 5.0°F.

Washington County gets 33.2" of precipitation a year, and 41% 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	22.3°	5.0°	0.85"
February	27.7°	7.8°	0.92"
March	40.7°	20.0°	1.62"
April	55.1°	33.9°	2.97"
May	67.2°	46.9°	4.17"
June	75.8°	57.5°	4.79"
July	79.3°	62.3°	4.38"
August	77.7°	60.4°	4.41"
September	70.7°	51.2°	3.32"
October	57.7°	38.0°	2.74"
November	41.4°	25.1°	1.82"
December	27.5°	12.5°	1.21"

Rainfall by month

Precipitation is spread fairly evenly through the year here, with 41% falling in the wettest three months (Jun, Jul, Aug).

January 0.85"

February 0.92"

March 1.62"

April 2.97"

May 4.17"

June 4.79"

July 4.38"

August 4.41"

September 3.32"

October 2.74"

November 1.82"

December 1.21"

Annual total 33.2"

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 511

Heating degree days How much heating the climate demands 8,007

Approximate annual cooling cost At 16.95¢/kWh, Minnesota average $87

Approximate annual electric heating cost Lower where heating is gas rather than electric $475

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 Washington County, where electricity is one line of eight.

Common questions

What is the weather like in Washington County?

Washington County averages a high of 79.3°F in July and a low of 5.0°F in January. Annual precipitation is 33.2 inches, with essentially no snow.

When is the rainy season in Washington County?

The wettest stretch is Jun, Jul, Aug, which accounts for 41% of the year's precipitation. Precipitation is relatively evenly distributed across the year.

How hot does it get in Washington County?

The average daily high in July, the hottest month, is 79.3°F. That drives 511 cooling degree days a year, which is what your air conditioning has to work against.

Does it snow in Washington County?

Effectively no. Measurable snowfall is rare in Washington County.

Sources

Temperature, precipitation and snowfall normals — NOAA National Centers for Environmental Information, 1991–2020 Monthly Climate Normals, station STILLWATER 2SW, MN US (USC00218039), 1.9 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, Minnesota residential average.
Wet-season share is the wettest three consecutive months as a percentage of annual precipitation, calculated from the monthly normals.