Day 25 (2026-03-25) — 16th consecutive zero-precipitation day
Zero precipitation across all 37 HUC12s for the third consecutive day shown in the data window. 7-day antecedent precipitation remains 0.0" everywhere (with a trivial 0.003" in one ungauged HUC12). This is now 16 consecutive days without measurable rainfall across the entire watershed — the longest dry spell of the study by a wide margin.
No significant rises at any gauge. All gauges continue slow baseflow recession. End-of-day (EOD) values and notable observations:
| Gauge | EOD Value | Day 24 EOD | Change | Status |
|---|---|---|---|---|
| Boxley | 1.94 ft | 1.96 ft | -0.02 ft | New study low — first time below 1.96 ft |
| Ponca | 99.3 cfs | 104 cfs | -4.7 cfs (-4.5%) | Dropped below 100 cfs for first time — reading 99.3 at 22:45 CST |
| Pruitt | 3.66 ft / ~87 cfs | 3.69 ft / ~92 cfs | -0.03 ft | CFS minimum hit 81.1 during afternoon — deepest low yet. Height increasingly noisy (0.08 ft range). |
| St. Joe | 3.67 ft / 239 cfs | 3.75 ft / 263 cfs | -0.08 ft / -24 cfs (-9.1%) | Noticeable continued decline — still decelerating but not yet at floor |
| Harriet | 3.75 ft / 270 cfs | 3.81 ft / 300 cfs | -0.06 ft / -30 cfs (-10%) | Stepped down notably — settled at 270 cfs by ~18:00, then held flat for 5+ hours |
| Richland | 1.02 ft | 1.05 ft | -0.03 ft (central tendency) | Noisy (0.01-0.09 ft spikes) but central tendency ~1.02-1.03 ft. Hit 1.01 ft at 19:15 — new study low |
| Bear Creek | 2.31 ft / 6.0 cfs | 2.32 ft / 6.6 cfs | -0.01 ft | CFS now reading 6.0-6.02 regularly — new study low. Specific discharge: 0.025 cfs/km² |
Key observations: - Ponca crossed below 100 cfs for the first time in the study, ending the day at 99.3 cfs. This is now firmly in the "Too Low" category (<150 cfs). The recession rate has slowed dramatically — only ~3 cfs/day decline, suggesting we're very close to the baseflow floor. - Pruitt height continues declining but CFS values are increasingly unreliable at this stage level. The 81.1 cfs reading at 16:00 CST is likely an artifact of the gauge's river-right scouring issue (per local knowledge). Height-based analysis shows the gauge is still declining at ~0.03 ft/day. - Harriet showed its most notable single-day decline in weeks (-30 cfs, -10%), but then appeared to stabilize at exactly 270 cfs for the final 5 hours of the day. This may indicate approach to a new baseflow floor. - St. Joe also declined notably (-24 cfs) but CFS noise (±6 cfs oscillations) makes precise floor identification difficult. The height trend (3.67 ft central tendency EOD) is more reliable.
None — no precipitation occurred.
Not applicable — no event in progress.
The extended dry recession continues (Day 16 of zero precip). This is providing excellent deep baseflow characterization data.
Recession rate tracking (Day 24→25): | Gauge | Rate (cfs/day) | Rate (%/day) | Trend | |-------|---------------|-------------|-------| | Ponca | ~3 cfs/day | ~3% | Approaching zero — floor imminent | | St. Joe | ~24 cfs/day | ~9% | Still declining meaningfully | | Harriet | ~30 cfs/day | ~10% | Declining but may have hit step at 270 |
Notable: St. Joe and Harriet are still declining at significant rates (~9-10%/day) while Ponca has nearly flatlined. This likely reflects the much larger contributing area at the downstream gauges — deep groundwater drainage from the 1,342 km² St. Joe zone and 430 km² Harriet zone is still slowly depleting, while the smaller Ponca zone (298 km²) has nearly exhausted its subsurface storage.
Ponca reading below 100 cfs while Pruitt CFS appears lower (81-92 cfs): This continues the known Ponca>Pruitt CFS discrepancy at low flows. Per local knowledge, the Pruitt gauge reads artificially low due to channel scouring directing flow to river right. The height data is more trustworthy — Pruitt height (3.66 ft) should represent real flow of approximately 100+ cfs based on the general rating curve behavior. The 81.1 cfs reading is almost certainly an artifact.
Harriet stabilization at exactly 270 cfs: The Harriet gauge locked onto 270 cfs for the final ~5 hours (18:15-22:45). This looks like it may be approaching a rating curve quantization step rather than a true hydrologic stabilization. Height also flattened at 3.75 ft. This could represent the true baseflow floor for this gauge at this time of year, or it could have further to drop. Need more data.
Richland Creek hit 1.01 ft — a new absolute study low. The karst spring variability (±0.03 ft spikes with no rain) continues to be a feature of this gauge. The underlying central tendency is ~1.02 ft.