Inflow forecast
model output — not a measurementNOAA’s National Water Model, short-range run issued Jul 13, 3 PM MDT, for the 1 gauged tributary reach feeding Jordanelle Reservoir. The model routes rainfall that has already fallen plus near-term forecast precipitation.
Gauged inflow now
44.4
cfs · measured
Peak next 18h
87.9
cfs · ~3 AM MDT · modeled
Projected volume
119
acre-feet over 18h · modeled
Naive lake effect
+0.05 ft
if it all reached Jordanelle · 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. Flows are projected to rise meaningfully. National Water Model via NOAA/NWS · public domain.
The “naive lake effect” spreads the projected inflow volume over the lake’s estimated current surface area, ignoring travel time, channel losses, upstream storage decisions, and releases — it is a scale reference, not a prediction of the actual lake level. During floods, watch the live dashboard instead.