Day 26 (2026-03-26) — 18th consecutive zero-precipitation day
Zero precipitation across all 37 HUC12s. All gauge rain gauges recorded 0.0". 7-day antecedent precipitation is 0.0" everywhere (the trace 0.003" in HUC12 0508 from prior days has now fallen out of the 7-day window). This is the driest antecedent state of the entire study.
No rainfall-driven responses. All gauges continue slow baseflow recession. End-of-day values and changes from Day 25:
| Gauge | Day 25 EOD | Day 26 EOD | Change | Notes |
|---|---|---|---|---|
| Boxley | 1.94 ft | 1.92 ft | -0.02 ft | New study low. Previous low was 1.94 ft. |
| Ponca | 99.3 cfs | 96.4 cfs | -2.9 cfs | New study low. Dropped below 97.8 cfs step late in day. Recession continues but slowing (~3 cfs/day → ~2.9 cfs/day). |
| Pruitt | 3.66 ft / 86.5 cfs | 3.63 ft / 81.1 cfs | -0.03 ft / -5.4 cfs | Height hit new study low of 3.59 ft at 18:00. CFS hit 74.0 at same time — new study low and deeply suspect. |
| St. Joe | 3.67 ft / 239 cfs | 3.62 ft / 225 cfs | -0.05 ft / -14 cfs | Height hit 3.61 ft — new study low. Still declining meaningfully. |
| Harriet | 3.75 ft / 270 cfs | 3.71 ft / 251 cfs | -0.04 ft / -19 cfs | New study lows for both height and CFS. Dropped below the 270 cfs plateau seen on Day 25. |
| Richland | 1.02 ft | 0.99 ft | -0.03 ft | New study low at 0.99 ft. First time below 1.00 ft. Hit 0.99 at 21:15. Karst spikes still present (1.05 at 19:00 then back to 1.00 by 19:15). |
| Bear Creek | 2.31 ft / 6.0 cfs | 2.30 ft / 5.5 cfs | -0.01 ft / -0.5 cfs | New study lows. Height dropped to 2.30 ft, CFS to 5.5. |
All seven gauges set new study lows today. This is the first day of the study where every single gauge reached its minimum observed value.
None — no precipitation.
No event propagation. However, the recession pattern continues to show the downstream-lagged recession noted previously. Harriet's more noticeable drop today (-19 cfs) relative to recent days suggests it is now entering the steeper part of its recession curve that upstream gauges passed through 2-3 days ago.
Extended dry recession continues. Key recession rate observations:
| Gauge | Day 25 Rate (approx) | Day 26 Rate (approx) | Trend |
|---|---|---|---|
| Ponca | ~0.12%/hr (~3 cfs/day) | ~0.12%/hr (~2.9 cfs/day) | Approaching asymptote |
| St. Joe | ~0.16%/hr (~14 cfs/day) | ~0.14%/hr (~14 cfs/day) | Continued decline, decelerating |
| Harriet | ~0.17%/hr | ~0.30%/hr | Accelerated — broke off plateau |
Harriet's behavior is notable: After holding at ~270 cfs for most of Day 25, it stepped down to 251 cfs by EOD Day 26 — a 19 cfs drop in one day after being nearly flat. This suggests the 270 cfs level was a temporary quasi-stable state (possibly supported by a specific spring or groundwater contribution) that has now been exhausted.
Pruitt CFS continues to diverge from expected patterns. The 74.0 cfs reading at 18:00 CST (corresponding to height 3.59 ft) is almost certainly an artifact of the river-right scouring issue noted in local knowledge. A height of 3.59 ft at Pruitt with CFS of 74.0 would imply the Ponca-to-Pruitt reach is losing approximately 23 cfs (97.8 → 74.0) — physically implausible for a gaining river unless massive karst losses exist. The true flow at Pruitt is likely in the 90-100 cfs range based on upstream gauge values plus expected lateral inflows. The Pruitt CFS data should be disregarded at these low flows; height-based analysis is the only reliable approach for this gauge in current conditions.
Richland Creek hit 0.99 ft — the first sub-1.00 reading of the study. This, combined with continued karst spikes (0.05 ft jumps and drops within 15-minute intervals), reinforces that this gauge is dominated by karst spring dynamics at baseflow. The noise floor is roughly ±0.03-0.05 ft, making detection of small rainfall responses very difficult.
Ponca approaching new quantization level. The 97.8 cfs reading appeared for the first time today (starting ~09:00). This is a new rating curve step — previous lowest was 99.3. The true baseflow floor at Ponca may be approaching ~96-97 cfs given the current trajectory.