COLUMBIA--GRAND COULEE DAM (GCDW1)
| Observed | Forecast/Trend Issued: 2026-10-26 09:50 PDT | ||
| Date/Time (PDT) | Inflow | Date/Time (PDT) | Inflow |
| 2026-10-26 00:00 | 52600 | 2026-10-26 17:00 | 61940.29 |
| 2026-10-25 00:00 | 57400 | 2026-10-26 23:00 | 62187.04 |
| 2026-10-24 00:00 | 56200 | 2026-10-27 05:00 | 62227.26 |
| 2026-10-23 00:00 | 58200 | 2026-10-27 11:00 | 62146.93 |
| 2026-10-22 00:00 | 60500 | 2026-10-27 17:00 | 62054.16 |
| 2026-10-21 00:00 | 64800 | 2026-10-27 23:00 | 61918.84 |
| 2026-10-20 00:00 | 60100 | 2026-10-28 05:00 | 61648.62 |
| 2026-10-19 00:00 | 60200 | 2026-10-28 11:00 | 61198.11 |
| 2026-10-18 00:00 | 62200 | 2026-10-28 17:00 | 60656.12 |
| 2026-10-17 00:00 | 70900 | 2026-10-28 23:00 | 60183.63 |
| 2026-10-16 00:00 | 65900 | 2026-10-29 05:00 | 59883.6 |
| 2026-10-29 11:00 | 59751.2 | ||
| 2026-10-29 17:00 | 59705 | ||
| 2026-10-29 23:00 | 59648.48 | ||
| 2026-10-30 05:00 | 59524.23 | ||
| 2026-10-30 11:00 | 59327.34 | ||
| 2026-10-30 17:00 | 59082.67 | ||
| 2026-10-30 23:00 | 58824.32 | ||
| 2026-10-31 05:00 | 58773.83 | ||
| 2026-10-31 11:00 | 59437.3 | ||
| 2026-10-31 17:00 | 60793.44 | ||
| 2026-11-01 00:00 | 61957.49 | ||
| 2026-11-01 05:00 | 62417.96 | ||
| 2026-11-01 11:00 | 62471.07 | ||
| 2026-11-01 17:00 | 62426.44 | ||
| 2026-11-01 23:00 | 62358.63 | ||
| 2026-11-02 05:00 | 62288.41 | ||
| 2026-11-02 11:00 | 62225.61 | ||
| 2026-11-02 17:00 | 62168.38 | ||
| 2026-11-02 23:00 | 62111.67 | ||
| 2026-11-03 05:00 | 62051.48 | ||
| 2026-11-03 11:00 | 61987.51 | ||
| 2026-11-03 17:00 | 61918.67 | ||
| 2026-11-03 23:00 | 61841.35 | ||
| 2026-11-04 05:00 | 61749.04 | ||
| 2026-11-04 11:00 | 61637.06 | ||
| 2026-11-04 17:00 | 61499.8 | ||
| 2026-11-04 23:00 | 61330.57 | ||
| 2026-11-05 05:00 | 61207.63 | ||