hydrowet

Inflow forecast

model output — not a measurement

NOAA’s National Water Model, short-range run issued Sep 14, 11 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

36.6

cfs · measured

Peak next 18h

95.7

cfs · ~3 PM MDT · modeled

Projected volume

119

acre-feet over 18h · modeled

Net lake effect

-0.10 ft

after 227 cfs out · inferred

Projected flow by tributary reach

28568512 AM9 AM5 PM
ProvoTotal (all gauged reaches)

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 “net lake effect” nets the projected inflow volume against the water currently leaving the lake (227 cfs — Provo River below the dam, right now), held constant over the horizon, spread over the lake’s estimated surface area (before releases it would be +0.05 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.