30-year climate normals

Chelan County Climate and Weather Averages

Hottest month — July

81.9°

average daily high. The coldest month is January, averaging a low of 21.3°F.

Chelan County gets 27.24" of precipitation a year and 117.3" of snow, and 52% of it falls in Nov, Dec, Jan.

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	Snow
January	33.7°	21.3°	4.57"	31.5"
February	40.2°	22.7°	2.95"	17.4"
March	48.0°	26.9°	2.43"	9.5"
April	57.3°	31.7°	1.25"	1.1"
May	66.8°	39.1°	1.31"	0.1"
June	72.9°	45.0°	0.88"	0.0"
July	81.9°	50.2°	0.48"	0.0"
August	81.9°	49.3°	0.42"	0.0"
September	74.0°	41.6°	0.79"	0.0"
October	58.0°	33.4°	2.61"	1.0"
November	41.7°	27.2°	4.58"	14.6"
December	32.4°	21.4°	4.97"	42.1"

Rainfall by month

Chelan County has a distinct wet season. 52% of the year's precipitation arrives in Nov, Dec, Jan.

January 4.57"

February 2.95"

March 2.43"

April 1.25"

May 1.31"

June 0.88"

July 0.48"

August 0.42"

September 0.79"

October 2.61"

November 4.58"

December 4.97"

Annual total 27.24"

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 219

Heating degree days How much heating the climate demands 7,206

Approximate annual cooling cost At 14.95¢/kWh, Washington average $33

Approximate annual electric heating cost Lower where heating is gas rather than electric $377

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 Chelan County, where electricity is one line of eight.

Common questions

What is the weather like in Chelan County?

Chelan County averages a high of 81.9°F in July and a low of 21.3°F in January. Annual precipitation is 27.24 inches, including 117.3 inches of snow.

When is the rainy season in Chelan County?

The wettest stretch is Nov, Dec, Jan, which accounts for 52% 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 Chelan County?

The average daily high in July, the hottest month, is 81.9°F. That drives 219 cooling degree days a year, which is what your air conditioning has to work against.

Does it snow in Chelan County?

Yes. Chelan County averages 117.3 inches of snow a year.

Sources

Temperature, precipitation and snowfall normals — NOAA National Centers for Environmental Information, 1991–2020 Monthly Climate Normals, station PLAIN, WA US (USC00456534), 5.4 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, Washington residential average.
Wet-season share is the wettest three consecutive months as a percentage of annual precipitation, calculated from the monthly normals.