PoC pipeline: 274 GRIB subsets per cycle, 7 days hourly

20 July 2026

Each forecast cycle pulls 274 tiny GRIB subsets (137 wave + 137 atmosphere) from NOAA’s noaa-gfs-bdp-pds bucket using .idx indexes and HTTP Range requests. Ocean variables use the nearest wet grid cell so nearshore land masks don’t corrupt the read.

The headline metric is NOAA’s combined significant wave height (HTSGW), shown in feet; the groundswell partition stays visible as secondary detail. A not-worse coverage guard means a bad run never overwrites a good forecast.