Classification: partial Confidence: Model showing improved calibration with smaller errors after recent adjustments - headwater bands gaining confidence
Model underpredicted a 0.43 ft rise by 0.13 ft (4.3%) during a headwater-dominated rainfall event with broad hydrograph shape.
| Metric | Predicted | Actual | Error |
|---|---|---|---|
| Peak height | 2.91 ft | 3.04 ft | -0.13 ft |
| Total rise | — | 0.43 ft | — |
| Band | Precip | Predicted Rise | Intensity | Moisture |
|---|---|---|---|---|
| 4 | 0.11" | 0.03 ft | LIGHT | NORMAL |
| 5 | 0.16" | 0.03 ft | LIGHT | NORMAL |
This event featured rainfall concentrated in the headwater bands (4-5) with 0.35-0.53 inches, while Band 1 received only 0.35 inches matching the gauge measurement. The broad hydrograph shape and 6.8-hour rise duration confirm headwater dominance with minimal near-gauge contribution. The model predicted 2.91 ft but actual peak reached 3.04 ft, representing a modest 4.3% underprediction.
The timing error of 22.4 hours suggests the model may have underestimated the speed of headwater response, though the broad shape was correctly captured. Given recent calibration events that showed consistent overprediction requiring downward adjustments, this underprediction indicates the model may now be slightly conservative for headwater-dominated events.
The relatively small magnitude of error (0.13 ft) and the fact that recent adjustments have been trending downward suggest only modest upward corrections are needed for the headwater bands. The broad hydrograph shape and timing suggest the dispersion parameters are reasonable but lag times for headwater bands may need slight reduction.
| Band | Change | Reason |
|---|---|---|
| 4 | +5% | Primary contributor with 0.35 inches - modest underprediction suggests small upward adjustment needed |
| 5 | +8% | Highest rainfall (0.53 inches) in headwaters - modest underprediction suggests small upward adjustment needed |
Model showing improved calibration with smaller errors after recent adjustments - headwater bands gaining confidence