Daily Analysis

PRE-ANALYSIS PER-GAUGE FACTS (2026-05-22):

• Boxley (height): first 2.14 ft @ 00:00 | max 2.14 ft @ 00:00 | last 2.09 ft @ 23:30 | intraday low 2.08 ft @ 18:00 | low→peak rise: 2.08 → 2.09 ft = +0.01 ft, ~1 hr lag. Essentially pure recession with tiny terminal bump.
• Ponca (cfs): first 116 @ 00:00 | max 116 @ 00:00–00:30 | last 105 @ 23:30 | intraday low 105 @ 19:45 | low→peak rise: none meaningful (flatline at 105–107 cfs after low). Pure recession.
• Pruitt (height): first 4.04 ft @ 00:00 | max 4.04 ft @ 00:00 | last 3.88 ft @ 23:30 | intraday low 3.88 ft @ 20:45 | low→peak rise: 3.88 → 3.89 ft = +0.01 ft (~15 min). Pure recession; precip gauge logged 0.08".
• St. Joe (height): first 4.75 ft @ 00:00 | max 4.75 ft @ 00:00 | last 4.40 ft @ 22:45 | intraday low 4.53 ft @ 08:45 | low→peak rise: 4.53 → 4.61 ft = +0.08 ft, ~1 hr lag (08:45 → 09:45) — a real within-day pulse riding on top of recession. CFS: 525 last, 691 first, with low 584 @ 08:45 → peak 622 @ 09:45/10:15 = +38 cfs sub-cycle. Gauge precip 0.69".
• Harriet (height): first 4.83 ft @ 00:00 | max 4.83 ft @ 00:00 | last 4.55 ft @ 22:45 | intraday low 4.55 ft @ 22:45 (continuing) | low→peak rise: none meaningful. Pure recession. Gauge precip 0.20".
• Richland Creek (height): first 1.68 ft @ 00:00 | max 1.85 ft @ 21:30–23:00 | last 1.85 ft @ 23:00 | intraday low 1.64 ft @ 06:45–09:30 | low→peak rise: 1.64 → 1.85 ft = +0.21 ft, ~12–14 hr lag (low 06:45–09:30 → peak 21:30+). Richland rising, peak likely tomorrow.
• Bear Creek (height/cfs): first 2.16 ft / 17.0 cfs @ 00:00 | max 2.21 ft @ 09:30 / 19.8 cfs @ 09:30 | last 2.18 ft / 18.1 cfs @ 23:15 | intraday low 2.16 ft @ 00:00–07:45 | low→peak rise: 2.16 → 2.21 ft = +0.05 ft, ~2 hr lag from peak QPE (14:02 UTC = 09:02 CDT → peak 09:30 CDT). Gauge precip 0.64".

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1. PRECIPITATION SUMMARY

A new watershed-wide convective event began today, with a strong SE/lower-watershed spatial bias — the inverse of Event 11's distribution. Basin-max 24-hr QPE = 0.687" (HUC 110100050403 Headwaters Bear Creek).

Zone totals (24-hr): - Bear Creek: 0.685" (peak 1-hr 0.209", max 6-hr 0.507") - Harriet: 0.563" (peak 1-hr 0.221", max 6-hr 0.517") — Brush Creek 0.644", Spring Cr 0.527" - Richland: 0.443" (peak 1-hr 0.178", max 6-hr 0.392") — Falling Water Cr 0.480", Hdwtrs Richland 0.406" - Ungauged: 0.435" - St. Joe: 0.362" — Outlet Richland Cr HUC 0308 at 0.514", Calf Cr 0.632", Rocky Hollow 0.519" (lower mainstem sub-group dominant) - Pruitt: 0.264" - Boxley: 0.235" - Ponca: 0.163"

Temporal pattern: Two clear pulses — an early afternoon convective core (peak 1-hr ~14:02 UTC = 09:02 CDT) concentrated in Bear Cr / Harriet / Calf Cr / ungauged sub-basins, then a second evening pulse (~19:02 UTC = 14:02 CDT and ~20:02 UTC = 15:02 CDT) over Richland sub-basins (HUC 0306 peak 0.178" @ 19:02 UTC, HUC 0308 peak 0.167" @ 19:02 UTC) and Big Creek (HUC 0304 0.132" @ 19:02 UTC). Spatial gradient: lower watershed got ~3× upper watershed.

Antecedent (7-day, today): Identical to Day 81 — basin-wide ~1.4–3.3", moist to wet post-Event 11. This is the first event with moist antecedent (Event-11-saturated) since Event 10's setup. Big shift from Event 11's dry-antecedent baseline (0.07–0.30").

2. GAUGE RESPONSES

• Boxley: No response. Light QPE (0.235") fell on still-receding gauge; baseflow recession dominant. Likely sub-detection given mid-afternoon timing of pulse.
• Ponca: No response. Recession 116→105 cfs, no perturbation despite 0.163" zone QPE.
• Pruitt: No response in height/discharge — pure recession 4.04→3.88 ft. Gauge precip 0.08" registered locally but contributing-area QPE only 0.264"; falling stage continues.
• St. Joe: First detection — small bump. Height fell 4.75 → 4.53 (08:45) then rose to 4.61 by 09:45 (+0.08 ft in 1 hr), then resumed recession. The 09:45 spike corresponds suspiciously to the gauge-local 0.69" precip and the early-afternoon convective pulse over Calf Cr / Rocky Hollow / mid-mainstem HUCs that drain near the gauge. Reading 4.53 @ 08:45 looks like a single-reading dip below trend; the resumed 4.61 plateau is the more reliable trend. Net signal: modest rebound interrupting recession, attributable to local 0.30–0.63" QPE on mainstem-misc HUCs near gauge. Closing at 4.40 ft / 525 cfs (still well in Optimal range).
• Harriet: No within-day rise despite 0.563" zone QPE — pure recession 4.83→4.55 ft. Expected: Harriet's response lag to its own zone is typically 12–24+ hr; the 14:00 CDT QPE pulse would be expected to show as a rise tomorrow.
• Richland Creek: Major response in progress. Low 1.64 ft @ 06:45–09:30 → rising steadily from 11:00 onward → 1.85 ft @ 21:00–23:00 (still rising at EOD). Rise so far: +0.21 ft over ~12 hr. Attributable cleanly to the 0.443" Richland zone QPE (peak 1-hr 0.178" @ 19:02 UTC = 14:02 CDT in HUC 0306). Peak gauge response not yet captured.
• Bear Creek: Clean rise captured. Low 2.16 ft @ 07:45 → peak 2.21 ft @ 09:30 (+0.05 ft), discharge 17.0 → 19.8 cfs (+2.8 cfs). Tight ~2-hr response from peak 1-hr QPE (HUC 0404 peak 0.209" @ 14:02 UTC = 09:02 CDT → gauge peak 09:30). Gauge now slowly receding at 2.18 ft.

3. RAINFALL-RESPONSE PAIRS

Bear Creek (signal-rich today): - Zone QPE 0.685", peak 1-hr 0.209" @ 09:02 CDT, max 6-hr 0.507" - Gauge peak 2.21 ft @ 09:30 CDT - Lag (peak QPE → peak gauge): ~28 minutes — fastest Bear Creek response on record. - Transfer ratio: 0.05 ft / 0.685" = 0.073 ft/in. Discharge transfer: 2.8 cfs / 0.685" = ~4.1 cfs/in. - Antecedent: moist (7-day = 1.149", Headwaters Bear Cr) — distinctly wetter than Event 11 onset (0.24"). - Cross-event comparison: Event 11 (dry antec) gave Bear Cr transfer ratio ~0.09 ft/in over 72+ hr. Today's 0.073 ft/in over 2 hr is anomalously fast yet still anomalously low. The ultra-fast lag is a huge departure — likely because only the early pulse has propagated; the second evening pulse may still be in transit. Confidence: this is a partial-response measurement; revisit after Day 84. - Refined hypothesis for Bear Creek: transfer ratio remains stuck in the 0.05–0.10 ft/in band regardless of antecedent. Lag varies wildly. The gauge appears insensitive (likely a wide, low-gradient channel with diffuse floodplain storage, or a downstream backwater control). Strong confirmation that Bear Creek transfer is structurally anomalous, not an antecedent artifact.

Richland Creek (in-progress): - Zone QPE 0.443", peak 1-hr 0.178" @ 14:02 CDT (HUC 0306) - Gauge still rising at 1.85 ft @ 23:00 (from 1.64 ft low @ 09:30). Peak not captured. - Provisional lag: peak QPE 14:02 → current latest data 23:00 = ~9 hr and still rising. Will exceed 9 hr for true peak. - Provisional transfer ratio: 0.21 ft so far / 0.443" = 0.47 ft/in (lower bound; will increase if rise continues). - Antecedent: moist (7-day = 1.708", Hdwtrs Richland). Compare to Event 11 (dry, 0.30" antec) → 0.73 ft/in. - Cross-event comparison: Even at provisional 0.47 ft/in, this is already lower than Event 11's dry-antec ratio of 0.73, contrary to the "wet amplifies" hypothesis. BUT — peak isn't captured. If rise continues another 0.10–0.30 ft tomorrow, ratio climbs to 0.7–1.1 ft/in. Hold judgment until Day 84.

St. Joe (ambiguous micro-response): - Zone QPE 0.362", peak 1-hr 0.167" @ 14:02 CDT (HUC 0308 — Outlet Richland) - Within-day pulse +0.08 ft @ 09:45 — but this precedes the peak QPE by ~4 hr, so attribution is to the earlier ~09:00 CDT convective pulse, not the 14:02 peak. Peak QPE response should still be coming overnight/tomorrow. - Provisional lag for early-pulse response: ~30–60 min (very local, very fast) — too fast to be from St. Joe sub-zone routing; this is the gauge-local 0.69" rain registering at the precip sensor producing direct/co-located runoff plus immediate Outlet Richland HUC 0308 response. - Cannot compute clean transfer ratio yet. Watch tomorrow.

4. DOWNSTREAM PROPAGATION

No clean mainstem propagation chain today — only St. Joe shows a meaningful disturbance, and no Boxley/Ponca/Pruitt forcing precedes it. Today's event is laterally injected from lower-watershed sub-zones (Bear Cr, Harriet zone, Richland, lower St. Joe sub-basins), not propagated downstream. Expect tomorrow's analysis to capture the Richland-driven St. Joe pulse propagating to Harriet.

5. MULTI-DAY EVENTS

This is Event 12 — onset, distinct from Event 11 (Event 11 recession had nearly completed at mainstem gauges; Boxley/Ponca/Pruitt/St. Joe/Harriet all in deep recession at start of today). Event 12 forcing today; gauge responses just beginning. Will track over Days 83–85+.

6. ANOMALIES OR SURPRISES

1. Spatially inverted event (lower-watershed-heavy) — second time in study (first was Day 77 sub-threshold). This is the first above-threshold spatially-inverted event, and gives a clean test of the lower-watershed-only response signature.
2. Bear Creek lag collapsed to ~30 min today vs. 72+ hr in Event 11. Suggests the slow Event 11 response was indeed antecedent-driven (dry channel storage absorbing pulse), and that with moist antecedent Bear Cr responds quickly. The transfer ratio stays low regardless — supporting a structural channel/floodplain explanation for the low ratio.
3. St. Joe single-reading dip 4.53 ft @ 08:45 looks like sensor noise or a bookkeeping artifact (drops 0.05 ft in 15 min then recovers). Treating as bad point.
4. Harriet zone got 0.563" but gauge in pure recession all day — confirms Harriet's long-lag character. Response should emerge Day 83.