Daily Analysis

Pre-analysis per-gauge facts

Gauge	First (00:00)	Intraday Max	Intraday Low	Last	Low→Peak Rise
Boxley	1.96 ft @ 00:00	1.96 ft @ 00:00	1.88 ft @ 22:45	1.88 ft @ 23:30	none (monotonic recession)
Ponca	91.0 cfs @ 00:00	91.0 cfs @ 00:00	81.3 cfs @ 21:00	81.3 cfs @ 23:30	none (monotonic recession)
Pruitt	3.82 ft / 131 cfs @ 00:00	3.84 ft @ 00:30 / 136 cfs @ 00:30	3.71 ft @ 19:30 / 106 cfs @ 19:30	3.71 ft / 106 cfs @ 23:30	+0.03 ft / +7 cfs from 19:30 low to 21:15 peak (3.74 ft / 113 cfs), lag ~1.75 hr
St. Joe	4.21 ft / 445 cfs @ 00:00	4.23 ft @ 10:30 / 453 cfs @ 10:30	4.11 ft / 405 cfs @ 22:45	4.11 ft / 405 cfs @ 22:45	+0.07 ft (4.16→4.23) from ~09:15 low to 10:30, but in context of mid-day noise; net day recession
Harriet	4.29 ft / 581 cfs @ 00:00	4.29 ft @ 00:00 / 581 cfs @ 00:00	4.26 ft / 561 cfs @ 17:15	4.26 ft / 561 cfs @ 22:45	none (slow recession)
Richland	1.60 ft @ 00:00	1.60 ft @ 00:00	1.49 ft @ 22:15	1.49 ft @ 23:00	none (monotonic recession)
Bear Creek	2.25 ft / 22.2 cfs @ 00:00	2.26 ft @ 00:30 / 22.9 cfs @ 00:30	2.21 ft / 19.8 cfs @ 19:30	2.21 ft / 19.8 cfs @ 23:15	+0.01 ft / +0.6 cfs blip at 20:15-20:45 (noise level)

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1. PRECIPITATION SUMMARY

Basin-wide dry day. Zero QPE across all 37 HUC12s. Day 86 marks the second fully dry day of the study (after Day 78, May 17). 7-day antecedent totals continue to slowly tick up at the lower-watershed ungauged HUC12s (Leatherwood 3.76", Bratton 3.38") from Event 12's Day 85 trailing pulse moving through the antecedent window, but no new forcing.

2. GAUGE RESPONSES

All gauges are in pure recession from Event 12. Magnitudes:

• Boxley: 1.96 → 1.88 ft (–0.08 ft over 24 hr). Now at the lowest point in 4+ weeks.
• Ponca: 91.0 → 81.3 cfs (–9.7 cfs, –10.7%). Below the 150-cfs "Too Low" threshold by a wide margin.
• Pruitt: 3.82 → 3.71 ft / 131 → 106 cfs (–0.11 ft, –25 cfs). The intraday wobble (3.84 max early, 3.74 secondary peak at 21:15) likely reflects residual Event 12 backwater/diurnal noise rather than new forcing — there was no QPE anywhere upstream.
• St. Joe: 4.21 → 4.11 ft / 445 → 405 cfs (–0.10 ft, –40 cfs). The 4.23 ft mid-day reading is within the gauge's typical ±0.03 ft noise band.
• Harriet: 4.29 → 4.26 ft / 581 → 561 cfs (–0.03 ft, –20 cfs). Slowest recession in the network as expected for the largest drainage area.
• Richland: 1.60 → 1.49 ft (–0.11 ft). Strong recession from Event 12's modest crest.
• Bear Creek: 2.25 → 2.21 ft / 22.2 → 19.8 cfs (–0.04 ft, –2.4 cfs). Continuing Event 12 recession.

3. RAINFALL-RESPONSE PAIRS

None. Zero forcing today.

4. DOWNSTREAM PROPAGATION

Not applicable. Recession only.

5. MULTI-DAY EVENTS

Day 86 is Day 4 of Event 12 recession (event peaked at Pruitt D85 10:45). The recession behavior across the network adds useful calibration:

Gauge	D85 EOD	D86 EOD	24-hr Δ	Recession rate
Boxley	1.96 ft	1.88 ft	–0.08 ft	typical for pool-and-drop
Ponca	91 cfs	81.3 cfs	–10.7%	exponential-decay-like
Pruitt	3.83 ft / 133 cfs	3.71 ft / 106 cfs	–0.12 ft / –20%	fast
St. Joe	4.20 ft / 441 cfs	4.11 ft / 405 cfs	–0.09 ft / –8%	moderate
Harriet	4.29 ft / 581 cfs	4.26 ft / 561 cfs	–0.03 ft / –3.4%	slowest (largest DA)
Richland	1.61 ft	1.49 ft	–0.12 ft	fast
Bear Cr	2.26 ft / 22.9 cfs	2.21 ft / 19.8 cfs	–0.05 ft / –13.5%	moderate

The monotonic recession ordering Harriet < St. Joe < Boxley ≈ Pruitt ≈ Richland is consistent with prior events: recession rate scales inversely with drainage area, as expected for storage-dominated baseflow.

6. ANOMALIES OR SURPRISES

• Pruitt's intraday low→peak wobble at 19:30→21:15 (+0.03 ft / +7 cfs) is the only sub-recession signal anywhere in the network, but with zero QPE basin-wide, it cannot be attributed to forcing. Most likely it represents either (a) gauge measurement noise, or (b) a slow propagation pulse from very-late Event 12 trailing ungauged-zone runoff finally reaching Pruitt — but the geography is backwards for that (ungauged is downstream of Pruitt). I'll attribute this to gauge noise / minor diurnal effect. Worth noting because it's the only non-monotonic feature today.
• Ponca dropped below 100 cfs for the first time since early Event 11 onset. Confirms the moist-antecedent Event 12 did little to recharge upper-watershed baseflow.
• Richland fell below 1.50 ft, the lowest level recorded in this study to date. The 7-day antecedent in Richland HUCs (2.05–2.06") is still moderately wet, but the catchment is clearly draining efficiently and the prior Event 12 contribution to Richland was minimal.

With 4 days remaining in the study, this recession baseline is valuable: it gives the cleanest possible "what does dry-down look like after a moist-antecedent moderate event" reference for future transfer-function work.