Glossary
Plain-English explainers for the terms Lakebrief uses — small-craft sailing concepts, USGS parameter codes, datum conventions, NWS alert categories. Useful for sailors new to the inland scene.
Full pool elevation
The reference water-surface elevation that a reservoir is managed to hold during normal operations.
How to read a USGS reservoir gauge
USGS Water Services publishes real-time elevation, gauge height, and storage data for thousands of reservoirs. Reading them correctly takes one extra step.
What is a small-craft sailing score?
Lakebrief computes a 0–100 number that combines wind speed, gust risk, and rain into one go/no-go signal for small-craft sailors, with separate modifiers for visibility and convective risk.
NGVD29 vs NAVD88: which datum is your lake in?
The two vertical datums you'll see on US reservoir gauges, what each one means, and why a five-foot offset between them matters at full pool.
Small Craft Advisory and other NWS marine alerts
What the National Weather Service means when it issues a Small Craft Advisory, and how Lakebrief surfaces those alerts on each lake page.
ECMWF, GFS, ICON, HRRR: which forecast model is right?
The four numerical weather prediction models Lakebrief ensembles, what each is good at, and why disagreement between them is itself useful information.
Reservoir drawdown
The seasonal lowering of a reservoir below its full-pool elevation, why operators do it, and what it means for sailors.
Park-rule sustained-wind boating prohibitions
Some operating agencies post a hard wind cutoff that legally prohibits boating once exceeded. Why these rules exist and how Lakebrief handles them.