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Ross Dam, WA Climate

Temperature, precipitation, and comfort score from NOAA NCEI 1991-2020 normals →

30-year climate normals from 1 weather station (1991-2020).

Ross Dam, Washington has an average annual temperature of 49°F and a climate comfort score of 37/100 (Below Average). Annual precipitation totals 60.8", including 66.7" of snow. Based on NOAA 30-year normals (1991–2020).

Avg Temperature

49°F (10°C)

Avg High

57°F

Avg Low

41°F

Annual Precip

60.8"

Annual Snow

66.7"

Comfort Score

37/100

Below Average

Climate Comfort Score

37/100

Below Average

Avg Annual Temperature

49°F

30-year mean (NOAA NCEI)

Annual Precipitation

60.8"

Plus 66.7" of snow

Comfort score vs national 100-point ceiling (Ross Dam) 37.0%
National median (≈55)

PlainClimate composite — temperature mildness, humidity, precipitation, extreme-weather frequency. Below Average for the Ross Dam area.

Warming context for Ross Dam

Methodology

How the U.S. land temperature anomaly tracks against the global mean since 1900. The current NOAA 1991-2020 normal for Ross Dam captures average conditions across the spread shown — the most recent decade is warmer than the 30-year mean.

Warming context — U.S. vs global, with Paris reference lines Anomaly chart from 1900 to 2024. Local series shows warming of 0.11 °C per decade versus a global rate of 0.11 °C per decade (ratio 1.00). Paris Agreement thresholds at 1.5 and 2.0 °C are dashed. -1.0°C -0.5°C +0.0°C +0.5°C +1.0°C +1.5°C +2.0°C +2.5°C Paris 1.5°C Paris 2.0°C 1900192019401960198020002020
  • United States land mean (NOAA NCEI) +0.11 °C/decade
  • Global anomaly (NASA GISTEMP) +0.11 °C/decade
  • Paris Agreement thresholds 1.5°C / 2.0°C
Sources: NOAA NCEI, NASA GISTEMP. Paris thresholds per IPCC AR6 WG1.

Monthly Temperatures

Average daily high and low temperatures by month

Month Avg High Avg Low Mean
January 38°F (3°C) 30°F (-1°C) 34°F (1°C)
February 41°F (5°C) 31°F (-1°C) 36°F (2°C)
March 47°F (8°C) 33°F (1°C) 40°F (5°C)
April 56°F (13°C) 38°F (3°C) 47°F (8°C)
May 65°F (18°C) 45°F (7°C) 55°F (13°C)
June 70°F (21°C) 50°F (10°C) 60°F (16°C)
July 79°F (26°C) 55°F (13°C) 67°F (19°C)
August 79°F (26°C) 56°F (13°C) 67°F (20°C)
September 70°F (21°C) 50°F (10°C) 60°F (16°C)
October 56°F (13°C) 43°F (6°C) 49°F (10°C)
November 44°F (7°C) 35°F (2°C) 40°F (4°C)
December 38°F (3°C) 31°F (-1°C) 34°F (1°C)

Monthly Precipitation

Average monthly rainfall and snowfall

January 9.7"

Snow: 17.2"

18.6 days with precipitation

February 6.0"

Snow: 11.9"

15.3 days with precipitation

March 6.4"

Snow: 7.8"

18.1 days with precipitation

April 3.2"

Snow: 0.3"

14.5 days with precipitation

May 2.1"

11.8 days with precipitation

June 1.7"

11.3 days with precipitation

July 1.0"

6.3 days with precipitation

August 1.2"

5.7 days with precipitation

September 2.5"

10.5 days with precipitation

October 6.7"

16.4 days with precipitation

November 11.1"

Snow: 5.8"

20.4 days with precipitation

December 9.2"

Snow: 23.7"

18.8 days with precipitation

Frost Dates & Growing Season

First Fall Freeze

November 10

50% probability date

Last Spring Freeze

April 8

50% probability date

Heating & Cooling Degree Days

Annual totals indicate energy demand for heating and cooling

Heating Degree Days

6,083

Higher = more heating needed

Cooling Degree Days

303

Higher = more cooling needed

Warmest Month

August

Coldest Month

January

Related Data

Climate Guides

Climate Insight: Ross Dam, WA

The NOAA 1991–2020 climate normals describe Ross Dam, Washington as a location with an annual average temperature of 49°F, ranging from a mean daily high of 57°F to a mean daily low of 41°F. August is typically the warmest month of the year, while January is the coldest. These thirty-year averages, computed from station USC00457185, smooth out year-to-year variability and give a baseline expectation for typical conditions in any given month.

Precipitation patterns matter as much as temperature for anyone planning to live, garden, or travel here. Ross Dam receives roughly 60.8 inches of precipitation each year, with 66.7 inches typically falling as snow. Growing-season length varies with elevation and microclimate, with the last spring freeze near April 8 and the first fall freeze near November 10. For energy use, 6,083 heating degree days and 303 cooling degree days tell the story of how often furnaces and air conditioners run during a normal year.

On PlainClimate's composite comfort index, Ross Dam scores 37/100 (Below Average), a blended measure that weighs temperature mildness, precipitation moderation, and extreme-weather frequency against one another. Use the monthly tables above to plan around specific windows — shoulder seasons for mild highs and lows, peak summer for August-driven heat, or deep winter for January-driven cold. All figures here are thirty-year averages: any single year may run warmer, wetter, drier, or cooler than the normal, so treat them as planning guidance rather than forecasts.

Frequently Asked Questions

What is the average temperature in Ross Dam, WA?
The average annual temperature in Ross Dam, Washington is 49°F. The warmest month averages 79°F (26°C) and the coldest averages 30°F (-1°C).
How much rain does Ross Dam get?
Ross Dam receives 60.8 inches of precipitation annually, including 66.7 inches of snow. Based on NOAA 30-year climate normals (1991-2020).
What is the comfort score for Ross Dam?
Ross Dam has a climate comfort score of 37/100 (Below Average). This score considers temperature mildness, humidity, precipitation, and extreme weather frequency.
When is the growing season in Ross Dam?
Growing season data is not available for Ross Dam.
How much energy does heating and cooling require in Ross Dam?
Ross Dam has 6,083 heating degree days and 303 cooling degree days annually. Higher heating degree days indicate greater winter energy demand, while higher cooling degree days indicate greater summer cooling needs.
Where does this Ross Dam climate data come from?
All climate data comes from NOAA U.S. Climate Normals v1.0.1, covering the 30-year period from 1991 to 2020. Data is collected from weather station USC00457185. These 30-year averages are the standard reference for typical weather conditions.

Data Sources

Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). Station: USC00457185. For informational purposes only.

Related

Data sourced from official public datasets. See our methodology for details. Retrieved and formatted by PlainClimate Editorial