Daily Analysis

PRE-ANALYSIS (per-gauge facts, all timestamps CDT):

• Boxley (height): (a) first 2.80 ft @00:00; (b) max 3.93 ft @14:00; (c) last 3.34 ft @23:30; (d) intraday low 2.74 ft @07:30–07:45; (e) low→peak +1.19 ft, 2.74→3.93, ~6.25 hr (07:45→14:00); largest hourly rise +0.60 ft @14:00. SIGNIFICANT RISE.
• Ponca (discharge): (a) first 213 cfs @00:00; (b) max 758 cfs @16:30; (c) last 475 cfs @23:30; (d) intraday low 196 cfs @07:15–07:45; (e) low→peak +562 cfs, 196→758, ~9 hr (07:30→16:30).
• Pruitt (height/discharge): (a) first 4.58 ft / 370 cfs @00:00; (b) max 5.81 ft / 838 cfs @23:30 — STILL RISING, peak not reached; (c) last 5.81 ft / 838 cfs; (d) intraday low 4.49 ft @07:30–07:45 / 340 cfs @05:30; (e) low→peak +1.32 ft / +498 cfs and climbing; largest hourly rise +0.49 ft @22:00.
• St. Joe (height/discharge): (a) first 5.51 ft / 1170 cfs @00:00 (= max); (b) max 5.51 ft / 1170 cfs @00:00; (c) last 5.27 ft / 1020 cfs; (d) low 5.26 ft @22:30 / 1010 cfs @22:30. Pure recession — max = first reading (one sub-resolution +0.04 ft blip @11:00 = noise). No attributable response.
• Harriet (height/discharge): (a) first 5.47 ft / 1560 cfs @00:00; (b) max 5.48 ft / 1570 cfs @00:15; (c) last 5.21 ft / 1310 cfs; (d) low 5.21 ft / 1310 cfs @22:45. Pure recession.
• Richland (height): first 1.35, max 1.35 @00:00, last 1.31, low 1.30 @22:30. Pure recession, new post-event low.
• Bear Creek (height/discharge): first 2.49 ft / 51.0 cfs, max 2.49/51.0 @00:00, last 2.42 ft / 43.1 cfs, low 2.42/43.1 @23:00. Pure recession, new post-event low. cfs steps down in standard 1.1–1.2-cfs increments — no rating step.

(f) QPE-peak timing for attribution: Boxley zone (Terrapin 0201) peak 1-hr 0.738" @09:02 CDT (14:02Z). Ponca zone (Beech 0202) peak 1-hr 0.689" @09:02 CDT. Pruitt zone (Cove 0204) peak 1-hr 0.431" @09:02 CDT.

1. PRECIPITATION SUMMARY

A clean upper-basin-concentrated morning event (peak 1-hr ~09:02 CDT). Zone-averages: Ponca 0.864" (basin-max; Beech 0.979"/0.689"/hr, Whiteley 0.834", Smith 0.780"), Boxley 0.851" (Terrapin 0.851"/0.738"/hr — day's highest intensity), Pruitt 0.609" (Cove 0.726", Hoskin 0.492", Flatrock 0.635"). Sharp downstream falloff: St. Joe zone 0.271", Harriet 0.213", Bear 0.145", Richland 0.056" (essentially dry). Antecedent very wet across the upper basin (Boxley 7-day 4.17", Ponca zone 4.0–4.5"). Spatially coherent single-pulse, upper-basin bullseye — the spatial complement of Event 20, and a smaller analog of Event 19.

2. GAUGE RESPONSES

• Boxley +1.19 ft (2.74→3.93), peak 14:00. Direct in-zone forcing on a primed pool. Crossed Hailstone Low-Floatable (3.7 ft) ~13:30–15:30 (~2 hr above) and the Boxley–Ponca section threshold (3.2 ft) from ~12:45 through end of day — first Hailstone-runnable window since Event 20.
• Ponca +562 cfs (196→758), peak 16:30. Direct Ponca-zone forcing + Boxley propagation. Note Ponca dipped to 196 cfs @07:15 (briefly below the 200-cfs Optimal floor, as projected Day-118) then the event lifted it back to 758 cfs (solidly Optimal) — the projected Optimal exit occurred and immediately reversed.
• Pruitt rising hard, 838 cfs / 5.81 ft and climbing at 23:30 — late-evening arrival = Ponca-cascade propagation + local 0.609" zone. Peak will fall on Day 120. Optimal.
• St. Joe & Harriet: pure recession (1170→1020; 1560→1310 cfs). Signal separation: Richland flat (0.056" zone) → the upper-basin pulse has NOT yet reached the trunk; expect arrival Day 120 (Pruitt→St. Joe 11–23 hr).
• Bear flat (Harriet-zone discriminator) → no lower-basin forcing; Bear/Richland at new post-event lows.

3. RAINFALL-RESPONSE PAIRS

• Boxley: lag = 14:00 − 09:02 = 4.97 hr (~5 hr). Transfer = 1.19 ft / 0.851" = 1.40 ft/in. Antecedent very wet, 7-day 4.17". Cross-event: matches the wet/primed Boxley anchors almost exactly — Event 4 (1.30), Event 20 Day-106 (1.42, 2-day cum 1.53"). Wet/wet match. Lag ~5 hr sits between Event 20 (5.97 hr) and Event 19 (3.7 hr) primed responses. No deviation >30% — strongly confirms the wet/primed Boxley transfer (~1.3–1.42 ft/in) and the pool-fill-is-pre-satisfied fast-lag regime.
• Ponca: lag (in-zone) = 16:30 − 09:02 = 7.47 hr; Boxley→Ponca propagation 14:00→16:30 = 2.5 hr (Ponca integrates both). Transfer = 562 / 0.864" = 651 cfs/in. Antecedent very wet (~4.0–4.5"). Cross-event: prior wet Ponca = ~1000–1220 cfs/in (Events 2, 20). Today ~651 cfs/in is ~40% below — FLAG. Most likely the Event-12 effect (sub-1.0" forcing → lower efficiency regardless of antecedent) plus a recession-suppressed baseline. Proposed refinement: add a "moist/wet but sub-1.0" forcing" Ponca node at ~650 cfs/in, distinct from the >1.0" wet node (~1000–1220).
• Pruitt: peak not yet reached — transfer/lag deferred to Day 120. Onset rise began ~18:00, steepened 21:00+ (>9 hr after the 09:02 local QPE peak) → dominantly Ponca-cascade propagation, not local direct.

4. DOWNSTREAM PROPAGATION

Cascade in progress (Event 22). Boxley 14:00 → Ponca 16:30 = 2.5 hr. Straight-line 10.3 km; at sinuosity 1.5 ≈ 15.5 km channel → 6.2 km/hr ≈ 1.72 m/s — but this is partly parallel direct forcing (Ponca had its own 0.86" zone), so treat as an upper bound on celerity, not pure routing. Ponca 16:30 → Pruitt (still rising 23:30, ≥7 hr) — consistent with the 5.25–7.5-hr Ponca→Pruitt at ~500–750 cfs; Pruitt peak expected ~00:00–02:00 Day 120. St. Joe/Harriet arrival expected Day 120 (Pruitt→St. Joe 11–23 hr).

5. MULTI-DAY EVENTS

Today is the onset of Event 22, a new upper-basin event distinct from Event 21's recession (which dominated Days 116–118). It interrupted the Event-20/21 recession: Boxley reset from 2.74→3.93 ft, Ponca from 196→758 cfs, Pruitt re-elevated and climbing. St. Joe/Harriet are still draining the Event-21 tail (mid-Optimal) and have not yet seen this pulse — the cascade will integrate over Day 120. Because forcing is upper-only and sub-1", expect Event-19-style attenuation toward the trunk (likely a modest St. Joe/Harriet bump, NOT a flood).

6. ANOMALIES OR SURPRISES

• Ponca transfer ~40% below the wet anchor — the day's one flag. Reinforces the Event-12 "sub-1.0"-forcing dilution" finding even on a very wet antecedent.
• Boxley wet/primed transfer reproduced a third time (1.40) — increasingly tight cluster at ~1.3–1.42 ft/in for wet/primed ~1" events. Confidence up.
• Boxley 7-day 4.17" is among the wettest antecedents of any Boxley event in the study, yet transfer (1.40) is not above the prior wet ceiling — supports the idea that Boxley wet-transfer asymptotes near ~1.4 ft/in for ~1"-class forcing (the 2.28 outlier required extreme >0.6"/hr intensity).
• No rating-curve steps anywhere — ~14 days post-Event-20 record peak, still no field-revision artifact.