| Station: | Castle Rock, Washington | Continent: | North America | ||
| River: | Cowlitz | Major Basin : | Columbia River | ||
| Country: | United States | Discharge into : | Pacific Ocean | ||
| Observation Period: | 1927 - 1984 | Total Months: | 696 | ||
| Latitude (dec deg): | 46.26 N | Area (km2): | 5796 | ||
| Longitude (dec deg): | 122.91 W | Elevation (m): | 6 | ||
| Annual Discharge: (m3/s): | 261.3 | (km3/yr): | 8.2 | ||
| Annual Runoff: (l/s/km2): | 45.1 | (mm/yr): | 1421.3 |
| Mean for Observation Period | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
| m3/sec | 402.3 | 359.3 | 305.7 | 298.9 | 310.2 | 277.0 | 152.7 | 82.1 | 76.4 | 132.2 | 304.6 | 439.9 |
| km3/mo | 1.1 | 0.9 | 0.8 | 0.8 | 0.8 | 0.7 | 0.4 | 0.2 | 0.2 | 0.4 | 0.8 | 1.2 |
| mm/mo | 185.9 | 150.0 | 141.3 | 133.7 | 143.3 | 123.9 | 70.6 | 38.0 | 34.2 | 61.1 | 136.2 | 203.3 |
| l/s/km2 | 69.4 | 62.0 | 52.7 | 51.6 | 53.5 | 47.8 | 26.3 | 14.2 | 13.2 | 22.8 | 52.5 | 75.9 |
