COLUMBIA--GRAND COULEE DAM (GCDW1)
| Observed | Forecast/Trend Issued: 2026-05-04 14:58 PDT | ||
| Date/Time (PDT) | Inflow | Date/Time (PDT) | Inflow |
| 2026-05-05 00:00 | 138000 | 2026-05-05 11:00 | 136536.18 |
| 2026-05-04 00:00 | 133900 | 2026-05-05 17:00 | 135558.88 |
| 2026-05-03 00:00 | 122600 | 2026-05-05 23:00 | 135042.92 |
| 2026-05-02 00:00 | 124600 | 2026-05-06 05:00 | 134786.21 |
| 2026-05-01 00:00 | 120800 | 2026-05-06 11:00 | 134646.21 |
| 2026-04-30 00:00 | 131600 | 2026-05-06 17:00 | 134582.14 |
| 2026-04-29 00:00 | 130100 | 2026-05-06 23:00 | 134504.71 |
| 2026-04-28 00:00 | 131100 | 2026-05-07 05:00 | 134376.4 |
| 2026-04-27 00:00 | 137600 | 2026-05-07 11:00 | 134285.52 |
| 2026-04-26 00:00 | 134200 | 2026-05-07 17:00 | 134636.4 |
| 2026-04-25 00:00 | 140700 | 2026-05-07 23:00 | 136037.87 |
| 2026-05-08 05:00 | 138664.15 | ||
| 2026-05-08 11:00 | 141837.27 | ||
| 2026-05-08 17:00 | 144581.51 | ||
| 2026-05-08 23:00 | 146427.43 | ||
| 2026-05-09 05:00 | 147472.9 | ||
| 2026-05-09 11:00 | 148035.02 | ||
| 2026-05-09 17:00 | 148401.84 | ||
| 2026-05-09 23:00 | 148720.78 | ||
| 2026-05-10 05:00 | 149027.53 | ||
| 2026-05-10 11:00 | 149339.31 | ||
| 2026-05-10 17:00 | 149668.08 | ||
| 2026-05-10 23:00 | 150022.17 | ||
| 2026-05-11 05:00 | 150448.24 | ||
| 2026-05-11 11:00 | 151076.84 | ||
| 2026-05-11 17:00 | 152034.33 | ||
| 2026-05-11 23:00 | 153271.56 | ||
| 2026-05-12 05:00 | 154583.42 | ||
| 2026-05-12 11:00 | 155793.4 | ||
| 2026-05-12 17:00 | 156826.52 | ||
| 2026-05-12 23:00 | 157650.21 | ||
| 2026-05-13 05:00 | 158267.32 | ||
| 2026-05-13 11:00 | 158744.89 | ||
| 2026-05-13 17:00 | 159174.06 | ||
| 2026-05-13 23:00 | 159593.8 | ||
| 2026-05-14 05:00 | 159996 | ||