Diablo Dam, WA Climate: Temperature & Rain by Month
Average temperature and precipitation from NOAA NCEI 1991–2020 normals →, with a derived climate comfort score
30-year climate normals (1991-2020) from Diablo Dam's primary NOAA station, DIABLO DAM.
The climate verdict for Diablo Dam
Water is the standout signal in Diablo Dam, Washington: 77.4 inches of precipitation in a normal year. Against that wet profile, NOAA records an annual average of 49°F. At 43/100 (moderate) the climate comfort score falls in the bottom third of the station-mapped U.S. score corpus, exceeding only 10% of scores.
- 49°F
- average temperature, NOAA 1991-2020 normal
- 43/100
- comfort score, above 10% of station-mapped location scores
- 77.4"
- annual precipitation · 46" snow
- 205 days
- growing season, frost-free days
Diablo Dam: NOAA 1991-2020 normals describe a typical year, not a forecast. Method: /methodology.
Normals record plate
Sheet USC00452157 · Diablo Dam, WA 49°F mean · 77.4" precip
TEMP-COOL · RANK-COOL · PHOTO-FINISH · PRCP-WET · SWING-MID · COMF-LOW · LOAD-HEAT · STN-1 · BOOK-FULL
- TEMP-COOL 49°F
- RANK-COOL #2,470
- PHOTO-FINISH ≈ Fence Lake
- PRCP-WET 77.4"
- SWING-MID 32°F
- COMF-LOW 43/100
- LOAD-HEAT 6,005 HDD
- STN-1 USC00452157
- BOOK-FULL 6/6 fields
Nearest mean-temperature peer: Fence Lake, NM (+ 0 °F mean)
Instrument codes from this station's NOAA 1991–2020 normals, mean temperature, corpus warmth rank, photo-finish peer station, precipitation band, seasonal swing, comfort composite, degree-day load, and field book, not a livability rating.
Mean-temperature neighbourhood
Nationwide NOAA normal poles and nearest peers, not a reprint of every WA station list.
- Diablo Dam (this station) 49°F
- Hot Burkes Garden, VA 49°F
- Near Fence Lake, NM 49°F
- Near Augustine, NM 49°F
- Near Prineville, OR 49°F
Climate Living Index · Diablo Dam
Diablo Dam: 44/100 · grade D
Diablo Dam publishes 5 of 6 Living Index dimensions (NOAA annual/seasonal normals · NOAA daily multivariate normals); 1 missing weight rescale to 100.
PlainClimate-derived for Diablo Dam, not an official NOAA rating. Rankings still use Comfort Score 43/100 (separate formula). Breakpoints and limits.
| Dimension | Station value | Score |
|---|---|---|
| Normal heat + freeze calendar | 98 calendar days | 76/100 · B |
| Frost-free season | 205 days/year | 68/100 · C |
| Annual temperature balance | 49.2°F · 18.3° from 67.5°F | 37/100 · F |
| Snowfall burden | 45.7 inches/year | 23/100 · F |
| Precipitation balance | 77.4 in · 42.4 from 35 in | 0/100 · F |
Diablo Dam · 2026-08-04 · NOAA NCEI Climate Normals · method · Comfort Score method.
Diablo Dam is a temperate Köppen climate: Csb
Coldest-month mean 34.0°F and warmest-month mean 66.4°F place this station in temperate, dry-summer, warm summer climates (Csb). Class Csb is the Peel et al. (2007) label for this station's monthly mean temperature and precipitation normals: temperate, specifically temperate, dry-summer, warm summer.
- Köppen code
- Csb
- Group
- Temperate
- Warmest month
- 66.4°F
- Coldest month
- 34.0°F
Source: official public datasets monthly normals (1991–2020) at the city’s primary station. This is a station classification, not a mapped regional consensus.
National standing · heating-led station
Where Diablo Dam sits across the climate record
Three NOAA fields for Diablo Dam's primary station, temperature, precipitation, and seasonal swing, are ranked against every station-mapped normal that carries the same field.
- Annual temperature
- 36th percentile warmth
- Mid-pack annual mean versus 6,861 station normals.
- Annual precipitation
- Top 1% wettest
- Diablo Dam's annual total ranks in the wetter third of 6,352 measured normals.
- Seasonal temperature swing
- Narrower than 87%
- Warmest-to-coldest month gap for Diablo Dam is compact versus 6,861 complete station-years.
How Diablo Dam compares across U.S. station-mapped locations
Diablo Dam's comfort score vs. all station-mapped locations
PlainClimate composite comfort index (1–100), NOAA 1991–2020 normals
43 10th percentile score exceeds 10% of 6,189 station-mapped location scores
- 0–10: 0 station-mapped locations (0%). Below this entry.
- 10–20: 0 station-mapped locations (0%). Below this entry.
- 20–30: 96 station-mapped locations (2%). Below this entry.
- 30–40: 280 station-mapped locations (5%). Below this entry.
- 40–50: 1,113 station-mapped locations (18%). This entry sits in this band.
- 50–60: 1,329 station-mapped locations (21%). Above this entry.
- 60–70: 1,236 station-mapped locations (20%). Above this entry.
- 70–80: 650 station-mapped locations (11%). Above this entry.
- 80–90: 921 station-mapped locations (15%). Above this entry.
- 90–100: 564 station-mapped locations (9%). Above this entry.
Source NOAA U.S. Climate Normals, PlainClimate comfort index · 1991–2020
Diablo Dam's measured station temperature trend
MethodologyAcross 81 complete annual observations from 1916 to 2025, DIABLO DAM warmed at a fitted rate of 0.17°C per decade. The line shows the fitted change relative to its first year, not raw year-to-year temperatures or a forecast.
- Diablo Dam primary station fitted change +0.17 °C/decade
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 |
The year, day by day
Summer here tops out rather than builds: the warmest normal high is 81°F around July 31, short of 90°F on every date, while 98 dates carry a normal low at or below freezing, the coldest 29°F near January 1.
The freezing stretch
The normal low stays at or below 32°F into March 8, then returns to freezing around December 2, covering 98 dates in all.
Derived from the normal daily minimum. This is a different measure from the 50%-probability frost dates shown elsewhere on this page, which come from NOAA’s frost product.
Where the wet dates fall
The likeliest wet date is November 19, when 65% of years recorded at least a hundredth of an inch. The driest is July 31 at 17%. Summed across the calendar, that is about 175 wet dates a year.
The widest day
July 31 carries the biggest normal gap between afternoon and dawn, 26°F between the normal high and the normal low.
Look up any date
Any date's 1991–2020 normal for Diablo Dam.
Where Diablo Dam Stands Nationally
This is one of the wettest normals climates ranked: about 77 inches of precipitation in a normal year, a total fewer than one station in ten surpasses.
Diablo Dam earns one nationally notable standing (outer quintile) against 6,860 NOAA 1991–2020 normals stations, middle-of-the-pack metrics stay silent here.
Monthly Precipitation
Average monthly rainfall and snowfall
Snow: 12.2"
18.8 days with precipitation
Snow: 9.9"
15.6 days with precipitation
Snow: 4.2"
19.0 days with precipitation
Snow: 0.3"
16.5 days with precipitation
12.8 days with precipitation
12.1 days with precipitation
6.4 days with precipitation
6.3 days with precipitation
10.8 days with precipitation
16.6 days with precipitation
Snow: 3.1"
19.9 days with precipitation
Snow: 16.0"
19.5 days with precipitation
Diablo Dam's wet season runs through the cold months
December, January and February carry 40% of the year's precipitation here, while June through August contribute 6%. That is the cool-season-dominant pattern of the West Coast and the higher inland West, where storm tracks swing south in winter and summer turns dry; the thermometer meanwhile shows a 32.4°F seasonal spread.
- Wettest month
- November, 13.7"
- Driest month
- July, 1.3"
- Wettest three months
- November, January, December (48% of the year)
Shares are computed from this station's own 1991-2020 monthly precipitation normals. A cool-season label means the December-February share reaches 35%. Where snow falls, the monthly figures above report liquid-equivalent precipitation, so a wet winter month is not necessarily a rainy one.
When it rains in Diablo Dam, it arrives in quantity
77.4" of precipitation falls across only about 174 wet days here, averaging 0.44 inches each. Fewer days carry more water: the year's total is delivered in comparatively heavy events rather than persistent damp.
- Days with measurable precipitation
- about 174 a year, 48% of all days
- Average depth per wet day
- 0.44 inches
- Most wet days
- November, about 20
- Fewest wet days
- August, about 6
A wet day is one recording at least 0.01 inches. These are 1991-2020 normals: they describe an average year, and a per-day average is not a forecast of any individual storm.
Winter brings real snow to Diablo Dam
Diablo Dam averages 45.7 inches of snowfall a year, with December the snowiest month on the normals, spread across roughly 16 days that record measurable snow. That is depth accumulating on the ground, which is why it can exceed the annual precipitation figure: precipitation counts the liquid the snow melts down to, and fresh snow is mostly air.
- Annual snowfall: 45.7 inches of depth.
- Days recording measurable snow: about 16 a year.
- At a rough ten-to-one melt ratio, snow accounts for on the order of 6% of the year's precipitation.
NOAA 1991-2020 normals. The ten-to-one ratio is a convention, not a measurement: real ratios vary with temperature, so treat the share as an order of magnitude rather than an exact split.
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
Nationwide similar cities
Other rankable U.S. places outside WA closest to Diablo Dam on two NOAA annual-normal axes (mean temperature and annual precipitation). Chip rows use distinct link sets.
Closest by average temperature
Nearest out-of-state peers by annual mean temperature (49°F here).
- Battle Creek, MI 49°F · 0.0°F off
- Beaconsfield, IA 49°F · 0.0°F off
- Black Forest, CO 49°F · 0.0°F off
- Council, ID 49°F · 0.0°F off
Closest by annual precipitation
Nearest out-of-state peers by annual precipitation (77.4" here), excluding temperature-peer places.
- Brookings, OR 77.6" · 0.2" off
- Seaside, OR 76.7" · 0.7" off
- Yachats, OR 78.3" · 0.9" off
- Kodiak, AK 78.3" · 0.9" off
Snow and freeze rhythm
When cold and snow define Diablo Dam
heating led · wet · mid swing
Diablo Dam's energy balance leans toward cold weather: 6,005 annual heating degree days against 245 for cooling. Its 32.4°F seasonal range still makes the monthly rows more useful than the annual average alone.
Diablo Dam's frost-free season lasts about 205 days, a middle-length window whose endpoints matter more than the annual average. It describes freeze probability, not year-specific planting conditions.
-
1. Diablo Dam coldest normal
January
The monthly mean of 34°F (1°C) sits near freezing, so cold nights and above-freezing afternoons share the same month.
-
2. Diablo Dam typical freeze period
January through December
The station reports average freezing days from January through December.
-
3. Diablo Dam snow peak
December
Diablo Dam averages 45.7 inches of snow a year, with December the snowiest month on the normals.
Questions about Diablo Dam's climate
How much snow does Diablo Dam get? ▼
How much energy does heating and cooling require in Diablo Dam? ▼
Data Sources
Data source: NOAA U.S. Climate Normals v1.0.1 (1991-2020). All figures on this page are from Diablo Dam's primary station: DIABLO DAM (USC00452157). For informational purposes only.
Place identity: U.S. Census Bureau 2024 Gazetteer places. The conservative exact name-and-state crosswalk finds no Census place match, so PlainClimate treats this as a station-mapped location and does not claim it is a municipality. No exact Gazetteer row for Diablo Dam; facility counts that depend on place identity are therefore an upper bound, not a municipal census.
On this page every temperature, precipitation, and derived score for Diablo Dam comes from its primary NOAA station record. No figure on this page is typed in by an editor - each value is rendered from NOAA 1991-2020 U.S. Climate Normals. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error. Data current as of 1991–2020 normals.