Sources
Open-Meteo — Wind (3 models)
Hourly 10 m wind speed, direction and gust forecasts at every run midpoint and station, from three independent forecast models blended into each score: the regional best-match model, NOAA GFS, and ECMWF IFS. A separate 48-point grid across the island drives the animated wind-flow map layer.
open-meteo.com ↗Open-Meteo — Marine
Hourly significant wave height, wind-wave height / period / direction, swell height / period / direction, sea-surface temperature and ocean current at every run midpoint and station. Wind waves feed the “bump quality” factor; swell feeds the exposure penalty and buoy arrows.
marine API docs ↗Open-Meteo — Atmospheric conditions
Hourly rain probability, precipitation rate, sky state (WMO weather code), cloud cover, visibility, UV index and air temperature at every forecast point. Thunderstorms, squalls and poor visibility reduce run scores. Note: satellite observations are already assimilated into all of these models (GFS, ECMWF and the regional best-match ingest scatterometer winds, altimeter wave heights and geostationary imagery every cycle).
API docs ↗NOAA CO-OPS — Tides
High/low tide predictions (MLLW datum) for the next 48 hours at the Honolulu Harbor and Mokuoloe (Kāneʻohe Bay) reference stations.
tidesandcurrents.noaa.gov ↗NWS — Active alerts
Live marine-relevant watches, warnings and advisories for Hawaiʻi (Small Craft Advisory, High Surf, Gale, tropical systems…). Shown as a banner on the runs page.
NWS Honolulu ↗NOAA and airport observations
Fresh NDBC buoy/coastal readings and Aviation Weather METARs validate the near-term forecast. A material disagreement lowers confidence; large observed seas reduce the score. Unavailable or stale readings are skipped and never treated as favorable conditions.
ndbc.noaa.gov ↗Active NWS alerts
Wind forecast by model
Model-by-model 10 m wind at each forecast point. The runs page scores against the blend of all three; disagreement between models lowers confidence.
Marine conditions
Atmospheric conditions
Rain, sky state, visibility and UV feed the run cards and scoring: thunderstorms and squally showers dock a run's score, and passing rain gets flagged.
Tide predictions (next 48 h)
Buoys & stations
Route documentation
Where each route in this region is publicly documented — race sites, guides and the surfski knowledge base.