Climate Comfort Score
43/100
Moderate
NOAA 1991–2020 normals 49°F annual avg Public-domain federal data
Diablo Dam, WA Climate
Average temperature, precipitation, and a comfort score, drawn from NOAA NCEI 1991–2020 normals →
- 49°F
- Avg annual temp
- 43/100
- Comfort score
- 77.4"
- Annual precip
- 205d
- Growing season
30-year climate normals from 1 weather station (1991-2020).
The climate verdict for Diablo Dam
Diablo Dam, Washington averages 49°F a year and scores 43/100 on the comfort index - moderate, milder than 8% of U.S. cities.
- 49°F
- average temperature, NOAA 1991-2020 normal
- 43/100
- comfort score, milder than 8% of U.S. cities
- 77.4"
- annual precipitation · 46" snow
- 205 days
- growing season, frost-free days
Based on NOAA U.S. Climate Normals (1991–2020) - 30-year averages describing the typical year, not a forecast.
Avg Temperature
49°F (10°C)
Avg High
58°F
Avg Low
41°F
Annual Precip
77.4"
Annual Snow
45.7"
Comfort Score
43/100
Moderate
Avg Annual Temperature
49°F
30-year mean (NOAA NCEI)
Annual Precipitation
77.4"
Plus 45.7" of snow
Comfort score vs national 100-point ceiling (Diablo Dam) 43.0%
National median (63)
PlainClimate composite, temperature mildness, humidity, precipitation, extreme-weather frequency. Moderate for the Diablo Dam area.
How Diablo Dam compares to every U.S. city
Diablo Dam's comfort score vs. all U.S. cities
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
43 Top 92% higher than 8% of 6,915 US cities
Each bar is a band; taller bars hold more US cities. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count, share, and where it sits relative to this entry.
Source NOAA U.S. Climate Normals, PlainClimate comfort index · 1991–2020
Warming context for Diablo Dam
MethodologySince 1900, U.S. land temperatures have tracked (and diverged from) the global mean - the chart below shows how. Diablo Dam's current NOAA 1991-2020 normal sits within that longer spread, and the most recent decade runs warmer than the 30-year mean.
- 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
Monthly Temperatures
Average daily high and low temperatures by month
| Month | Avg High | Avg Low | Mean | Precip | Snow | Freeze Days | 90°F+ Days |
|---|---|---|---|---|---|---|---|
| January | 39°F (4°C) | 30°F (-1°C) | 34°F (1°C) | 12.3" | 12.2" | 20.0 | 0.0 |
| February | 43°F (6°C) | 30°F (-1°C) | 37°F (3°C) | 7.4" | 9.9" | 18.0 | 0.0 |
| March | 49°F (9°C) | 33°F (1°C) | 41°F (5°C) | 8.2" | 4.2" | 12.8 | 0.0 |
| April | 57°F (14°C) | 38°F (3°C) | 47°F (9°C) | 4.6" | 0.3" | 3.5 | 0.0 |
| May | 66°F (19°C) | 44°F (7°C) | 55°F (13°C) | 2.7" | 0.0" | 0.2 | 0.5 |
| June | 70°F (21°C) | 49°F (10°C) | 60°F (15°C) | 2.3" | 0.0" | 0.0 | 1.6 |
| July | 78°F (26°C) | 53°F (12°C) | 66°F (19°C) | 1.3" | 0.0" | 0.0 | 4.1 |
| August | 79°F (26°C) | 54°F (12°C) | 66°F (19°C) | 1.5" | 0.0" | 0.0 | 4.5 |
| September | 71°F (22°C) | 49°F (9°C) | 60°F (16°C) | 3.4" | 0.0" | 0.0 | 1.1 |
| October | 58°F (14°C) | 42°F (5°C) | 50°F (10°C) | 8.6" | 0.0" | 1.3 | 0.0 |
| November | 45°F (7°C) | 35°F (2°C) | 40°F (4°C) | 13.7" | 3.1" | 9.9 | 0.0 |
| December | 38°F (3°C) | 30°F (-1°C) | 34°F (1°C) | 11.6" | 16.0" | 20.3 | 0.0 |
Monthly Precipitation
Average monthly rainfall and snowfall
January 12.3"
Snow: 12.2"
18.8 days with precipitation
February 7.4"
Snow: 9.9"
15.6 days with precipitation
March 8.2"
Snow: 4.2"
19.0 days with precipitation
April 4.6"
Snow: 0.3"
16.5 days with precipitation
May 2.7"
12.8 days with precipitation
June 2.3"
12.1 days with precipitation
July 1.3"
6.4 days with precipitation
August 1.5"
6.3 days with precipitation
September 3.4"
10.8 days with precipitation
October 8.6"
16.6 days with precipitation
November 13.7"
Snow: 3.1"
19.9 days with precipitation
December 11.6"
Snow: 16.0"
19.5 days with precipitation
Frost Dates & Growing Season
First Fall Freeze
November 1
50% probability date
Last Spring Freeze
April 10
50% probability date
Growing Season
205 days
Heating & Cooling Degree Days
Annual totals indicate energy demand for heating and cooling
Heating Degree Days
6,005
Higher = more heating needed
Cooling Degree Days
245
Higher = more cooling needed
Warmest Month
August
Coldest Month
January
What Diablo Dam's climate means for you
Diablo Dam runs 49°F a year - peaking in August, coldest in January.
- Gardeners get about 205 frost-free days, with the last spring freeze near April 10 - plan the planting calendar around it, not the regional average.
- Energy bills track 6,005 heating and 245 cooling degree days a year, higher means the furnace or AC runs more.
- Comparing places to live? Line this city up against nearby cities and the national rankings. See rankings
These are 30-year NOAA normals (1991–2020) - the typical year, not a forecast for any specific season.
Climate Guides
Climate Insight: Diablo Dam, WA
An annual average temperature of 49°F, ranging from a mean daily high of 58°F to a mean daily low of 41°F is what the NOAA 1991–2020 climate normals report for Diablo Dam, Washington. August is typically the warmest month of the year, while January is the coldest. That baseline comes from station USC00452157 and thirty years of averaging, so it reflects a typical month rather than any one year's swings.
Beyond temperature, Diablo Dam averages 77.4 inches of precipitation annually, with 45.7 inches typically falling as snow - a real factor for anyone planning to live, garden, or travel here. The frost-free season averages 205 days, which directly shapes the planting calendar and growing potential for the area, with the last spring freeze near April 10 and the first fall freeze near November 1. Turning to energy use, 6,005 heating degree days and 245 cooling degree days tell the story of how often furnaces and air conditioners run during a normal year.
On PlainClimate's composite comfort index, Diablo Dam scores 43/100 (Moderate), a blended measure that weighs temperature mildness, precipitation moderation, and extreme-weather frequency against one another. Shoulder seasons bring the mildest highs and lows in the monthly tables above, summer brings August-driven heat, and winter brings January-driven cold - use that rhythm for planning. These figures are thirty-year averages rather than forecasts, so a specific year may still run warmer, cooler, wetter, or drier than what's shown.
Frequently Asked Questions
What is the average temperature in Diablo Dam, WA? ▼
The average annual temperature in Diablo 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 Diablo Dam get? ▼
Diablo Dam receives 77.4 inches of precipitation annually, including 45.7 inches of snow. Based on NOAA 30-year climate normals (1991-2020).
What is the comfort score for Diablo Dam? ▼
Diablo Dam has a climate comfort score of 43/100 (Moderate), milder than 8% of U.S. cities in the PlainClimate database.
When is the growing season in Diablo Dam? ▼
Diablo Dam has approximately 205 frost-free days per year, with the last spring freeze around April 10 and the first fall freeze around November 1.
How much energy does heating and cooling require in Diablo Dam? ▼
Diablo Dam has 6,005 heating degree days and 245 cooling degree days annually, a heating-dominated climate. See our <a href="/guides/reading-weather-data/" class="underline hover:text-brand-600">guide to reading weather data</a> for what these figures mean.
Where does this Diablo Dam climate data come from? ▼
NOAA U.S. Climate Normals v1.0.1 (1991-2020), from weather station USC00452157 near Diablo Dam.
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). Station: USC00452157. For informational purposes only.
Read our methodology - how this data is sourced, computed, and verified.
Related
Data sourced from official public datasets. See our methodology for details. Retrieved and formatted by PlainClimate Editorial
Every figure on PlainClimate is rendered directly from NOAA 1991-2020 U.S. Climate Normals data, no number is typed in by an editor. This page draws directly on NOAA 1991-2020 U.S. Climate Normals data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.