Inflow forecast
model output — not a measurementNOAA’s National Water Model, short-range run issued Sep 14, 10 AM CDT, for the 1 gauged tributary reach feeding Canyon Lake. The model routes rainfall that has already fallen plus near-term forecast precipitation.
Gauged inflow now
86.5
cfs · measured
Peak next 18h
96.4
cfs · ~2 AM CDT · modeled
Projected volume
138
acre-feet over 18h · modeled
Net lake effect
-0.02 ft
after 161 cfs out · inferred
Projected flow by tributary reach
Dashed = forecast. Values are at the gauges, not at the lake — water takes hours to a couple of days to travel downstream from the gauges to the lake. National Water Model via NOAA/NWS · public domain.
The “net lake effect” nets the projected inflow volume against the water currently leaving the lake (161 cfs — Guadalupe at Sattler, right now), held constant over the horizon, spread over the lake’s estimated surface area (before releases it would be +0.02 ft). It ignores travel time, channel losses, and any change the dam operators make — a scale reference, not a prediction. During floods, watch the live dashboard instead.