Daily Analysis

Day 63 of 90. 27 days remain.

1. PRECIPITATION SUMMARY: Zero rainfall watershed-wide. All 37 HUC12s report 0.000" for the third consecutive day. 7-day antecedent values continue to decline as the late-April pulses age out of the window — Boxley zone now 2.15", Richland 1.75-2.23", Bear Creek 1.76", Harriet 1.50-2.13". Still substantially "wet" by study standards but trending dry.

2. GAUGE RESPONSES: All gauges in clean recession. No rises today.

3. Boxley: 2.72 → 2.57 ft (−0.15 ft, −0.006 ft/hr)
4. Ponca: 299 → 261 cfs (−38 cfs, ~−1.6 cfs/hr)
5. Pruitt: 4.58 → 4.36 ft / 347 → 278 cfs (−0.22 ft, −69 cfs)
6. St. Joe: 5.45 → 5.05 ft / 1090 → 851 cfs (−0.40 ft, −239 cfs, ~−10 cfs/hr)
7. Harriet: 5.34 → 4.97 ft / 1440 → 1100 cfs (−0.37 ft, −340 cfs, ~−14 cfs/hr)
8. Richland: 2.06 → 1.87 ft (−0.19 ft) — now near pre-event baseline

9. Bear Creek: 2.65 → 2.52 ft / 61.4 → 45.3 cfs (~−0.7 cfs/hr)

10. RAINFALL-RESPONSE PAIRS: None — no forcing today.

11. DOWNSTREAM PROPAGATION: N/A (recession only).

12. MULTI-DAY EVENTS — Event 8 recession, Day 4 post-peak: This is now a clean ~96-hour recession dataset for Event 8. Updating the recession curve characterization:

St. Joe recession trajectory (peak Day 61 00:30 at 2260 cfs): - +24 hr (Day 62): 1530 cfs (32% drop) - +48 hr (Day 63 ~00:30): ~1090 cfs (52% drop) - +72 hr (Day 64 equiv, end of Day 63): 851 cfs (62% drop) - Late-recession rate Day 62→63: ~10 cfs/hr — about 30% of the fast-phase rate (33 cfs/hr Day 60→61). Continuing the decay pattern.

Harriet recession trajectory (peak Day 61 09:30 at 2430 cfs): - +24 hr: 1940 cfs (20% drop) - +48 hr: 1450 cfs (40% drop) - +72 hr: 1100 cfs (55% drop) - Day 62→63 rate: ~14 cfs/hr.

Slow-phase floor revision: Yesterday's hypothesis estimated St. Joe ~1100 cfs / Harriet ~1400 cfs as the slow-phase floor. Today's data shows the recession is still active and has dropped through those values without leveling off. The slow-phase floor has not yet been reached. Current values (St. Joe 851, Harriet 1100) likely still recessing. This revises the hypothesis: there is no clear slow-phase floor at the watershed scale yet — the recession on the saturated-soil baseflow continues smoothly. Possible the actual floor is closer to pre-event (St. Joe ~830, Harriet ~1030).

Bear Creek (peak Day 60 02:30 at 558 cfs): Now 45.3 cfs at +93 hr post-peak. 92% recession in ~93 hr — confirms karst flashy character. Approaching pre-event 27.8 cfs.

Richland (peak Day 59 21:45 at 4.89 ft): Now 1.87 ft. Below pre-event 1.85 ft baseline at +75 hr post-peak. Recovered.

Pruitt: 278 cfs vs 281 cfs pre-event. Fully recovered to pre-event baseflow.

1. ANOMALIES OR SURPRISES:
2. The "saturated baseflow elevation" hypothesis from Day 62 is not as durable as I claimed yesterday. Pruitt is back to pre-event baseflow at +96 hr; Richland is at/below pre-event at +75 hr; only St. Joe and Harriet remain elevated, and their recessions are still smoothly proceeding (no plateau). This suggests the elevated baseflow is transient — driven by upstream reservoir-of-saturated-soil drainage that itself is finite. Without follow-on rainfall, the system is rapidly returning to dry-season baseflow.
3. Local knowledge calibration: System is now in extended dry recovery, similar to late March pre-Event 4 conditions. The "test saturated-floor amplification" experiment is becoming less relevant because the floor itself is dissipating.