The Town FilesBlack Diamond, Washington
City in King County · population 4,697 (2020 Census)
- Median home
- $779,100
- Household income
- $141,383
- Jan low / Jul high
- 33° / 77°
- Snow a year
- 18 in
- Tornadoes ≤10 mi since 1950
- 0
- Median age
- 38.1
Black Diamond is a city of 4,697 people in King County, Washington. The median home is worth $779,100, above the typical Washington town ($475,000). It ranks better for families than 90% of Washington towns, more upscale than 88% of Washington towns, better transit than 75% of Washington towns.
How Black Diamond ranks
Percentile among Washington towns with at least 500 people on The Town Files lifestyle rankings. 50 is typical for the state; 90 means better than 90% of Washington towns.
Homes and cost of living
The median home in Black Diamond is worth $779,100, above the typical Washington town ($475,000). Homes cost about 5.5 times the median household income of $141,383, which is more affordable than 44% of Washington towns. Median rent is $1,453 a month. 86.0% of households own their home.
| Housing | Black Diamond | Typical Washington town |
|---|---|---|
| Median home value | $779,100 | $475,000 |
| Median rent | $1,453 | $1,597 |
| Median household income | $141,383 | $90,625 |
| Home value ÷ income | 5.5× | 5.3× |
| Homeownership | 86.0% | 74.4% |
| Median year built | 2000 | 1985 |
| Seasonal / vacation homes | 2.2% | — |
Who lives in Black Diamond
| People | Black Diamond | Typical Washington town |
|---|---|---|
| Median age | 38.1 | 40.1 |
| Age 65 and over | 10.2% | 17.9% |
| Under 18 | 24.9% | — |
| Bachelor's degree or higher | 54.7% | 27.6% |
| Below the poverty line | 2.1% | 8.5% |
| Veterans | 5.9% | — |
| Born outside the U.S. | 19.0% | — |
| Work from home | 24.9% | 13.4% |
| Average commute | 37.5 min | 27.1 min |
| Homes with broadband | 95.9% | 93.9% |
Weather in Black Diamond
July highs average 77.0°F and January lows 33.0°F. About 59.7 inches of rain and melted snow fall a year, with 17.5 inches of snow (typical Washington town: 4.0 in). Expect about 5 days a year at 90°F or hotter and 70 nights at or below freezing.
Tornadoes, storms and disasters
NOAA's Storm Events Database has no tornado within 10 miles of Black Diamond since 1950.
Severe weather in King County since 1996
King County has been included in 35 federal disaster or emergency declarations since 1953, most often for fire, flood, biological.
| Declared | Incident | Declaration |
|---|---|---|
| April 7, 2026 | Flood | DR-4906: Severe Storms, Straight-Line Winds, Flooding, Landslides, And Mudslides |
| December 12, 2025 | Flood | EM-3629: Severe Storms, Straight-Line Winds, Flooding, Landslides, And Mudslides |
| April 28, 2024 | Severe Storm | DR-4775: Severe Winter Storms, Straight-Line Winds, Flooding, Landslides, And Mudslides |
| September 10, 2022 | Fire | FM-5455: Bolt Creek Fire |
| April 23, 2020 | Flood | DR-4539: Severe Storms, Flooding, Landslides, And Mudslides |
Jobs and pay in King County
King County had 1,449,785 jobs in 2024, paying an average of $132,279 a year. Unemployment was 3.4% in 2023; in Black Diamond itself the ACS puts it at 1.3%.
Public schools in Black Diamond
2 public schools with 743 students, about 16.9 students per teacher.
| School | Grades | Students | Per teacher |
|---|---|---|---|
| Black Diamond Elementary | K-5 | 412 | 16.5 |
| Sawyer Woods Elementary School | PK-5 | 331 | 17.4 |
Towns near Black Diamond
- Maple Valley, WA3.7 mi · 28,013 people · home $724,700
- Lake Morton-Berrydale, WA4.2 mi · 10,474 people · home $714,200
- Lake Holm, WA5.3 mi · 3,430 people · home $828,600
- Covington, WA5.3 mi · 20,777 people · home $637,300
- Hobart, WA6.7 mi · 6,767 people · home $950,300
- Enumclaw, WA7.9 mi · 12,543 people · home $524,600
- Auburn, WA9.1 mi · 87,256 people · home $547,900
- Maple Heights-Lake Desire, WA9.1 mi · 3,873 people · home $876,200
Black Diamond questions
Is Black Diamond, Washington a good place to retire?
On The Town Files lifestyle rankings, Black Diamond scores better for retirees than 57% of Washington towns and quieter than 57%. 10.2% of residents are 65 or older (median age 38.1).
How much does a house cost in Black Diamond?
The median owner-occupied home in Black Diamond is valued at $779,100 (Census ACS 2020–2024), against a median household income of $141,383, so homes cost about 5.5 times income. Median rent is $1,453 a month.
What is the weather like in Black Diamond?
July highs average 77.0°F and January lows 33.0°F (NOAA 1991–2020 normals). It gets about 59.7 inches of precipitation a year and 17.5 inches of snow.
Does Black Diamond get tornadoes?
No tornado has been recorded within 10 miles of Black Diamond in NOAA's Storm Events Database since 1950.
- U.S. Census Bureau, American Community Survey 5-year estimates (2020–2024)
- U.S. Census Bureau, 2020 Census and 2025 Gazetteer (2020 / 2025)
- NOAA NCEI U.S. Climate Normals (1991–2020)
- NOAA NCEI Storm Events Database (1950–2026)
- FEMA OpenFEMA Disaster Declarations (this product uses the FEMA OpenFEMA API but is not endorsed by FEMA) (1953–2026)
- NCES Common Core of Data (2023–24)
- BLS Quarterly Census of Employment and Wages; USDA ERS county unemployment (BLS LAUS) (2000–2024)
- The Town Files lifestyle rankings, built from federal demographic, school, crime and housing data (2025)