COLUMBIA--GRAND COULEE DAM (GCDW1)
| Observed | Forecast/Trend Issued: 2026-10-25 10:17 PDT | ||
| Date/Time (PDT) | Pool Height | Date/Time (PDT) | Pool Height |
| 2026-10-26 00:00 | 1288.03 | 2026-10-26 05:00 | 1288 |
| 2026-10-25 00:00 | 1287.76 | 2026-10-26 11:00 | 1288 |
| 2026-10-24 00:00 | 1287.52 | 2026-10-26 17:00 | 1288 |
| 2026-10-23 00:00 | 1287.37 | 2026-10-26 23:00 | 1288 |
| 2026-10-22 00:00 | 1287.27 | 2026-10-27 05:00 | 1288 |
| 2026-10-21 00:00 | 1287.2 | 2026-10-27 11:00 | 1288 |
| 2026-10-20 00:00 | 1287.04 | 2026-10-27 17:00 | 1288 |
| 2026-10-19 00:00 | 1286.9 | 2026-10-27 23:00 | 1288 |
| 2026-10-18 00:00 | 1286.82 | 2026-10-28 05:00 | 1288 |
| 2026-10-17 00:00 | 1286.48 | 2026-10-28 11:00 | 1288 |
| 2026-10-16 00:00 | 1285.99 | 2026-10-28 17:00 | 1288 |
| 2026-10-28 23:00 | 1288 | ||
| 2026-10-29 05:00 | 1288 | ||
| 2026-10-29 11:00 | 1288 | ||
| 2026-10-29 17:00 | 1288 | ||
| 2026-10-29 23:00 | 1288 | ||
| 2026-10-30 05:00 | 1288 | ||
| 2026-10-30 11:00 | 1288 | ||
| 2026-10-30 17:00 | 1288 | ||
| 2026-10-30 23:00 | 1288 | ||
| 2026-10-31 05:00 | 1287.95 | ||
| 2026-10-31 11:00 | 1287.85 | ||
| 2026-10-31 17:00 | 1287.74 | ||
| 2026-11-01 00:00 | 1287.62 | ||
| 2026-11-01 05:00 | 1287.49 | ||
| 2026-11-01 11:00 | 1287.34 | ||
| 2026-11-01 17:00 | 1287.16 | ||
| 2026-11-01 23:00 | 1286.97 | ||
| 2026-11-02 05:00 | 1286.76 | ||
| 2026-11-02 11:00 | 1286.53 | ||
| 2026-11-02 17:00 | 1286.31 | ||
| 2026-11-02 23:00 | 1286.08 | ||
| 2026-11-03 05:00 | 1285.86 | ||
| 2026-11-03 11:00 | 1285.63 | ||
| 2026-11-03 17:00 | 1285.4 | ||
| 2026-11-03 23:00 | 1285.17 | ||
| 2026-11-04 05:00 | 1284.94 | ||