{
  "series_id": "weather-forecast-skill",
  "version": "1.2.0",
  "question": "At 6-hour and 24-hour cutoffs, how accurately do archived NOAA HRRR forecasts predict NFL stadium temperature, wind, and precipitation?",
  "hypothesis": "Six-hour HRRR stadium forecasts have lower temperature, wind, and precipitation errors than paired 24-hour forecasts, with results reported separately for HRRRv3 and HRRRv4.",
  "estimand": "Mean game-window forecast error at registered 6-hour and 24-hour pregame cutoffs, plus the paired 6-hour-minus-24-hour difference for the same stadium-games.",
  "population": "NFL regular-season stadium-games with cutoff-safe archived HRRR forecasts and matched NOAA game-window observations",
  "outcomes": [
    "temperature mean absolute error in Celsius",
    "wind-speed mean absolute error in meters per second",
    "deterministic precipitation Brier score"
  ],
  "features": [
    "forecast horizon",
    "HRRR model version",
    "stadium grid point"
  ],
  "temporal_split": "Every forecast object must prove source availability before its registered cutoff; matched observations are joined only for retrospective scoring.",
  "baselines": [
    "paired 24-hour forecast error for each 6-hour forecast",
    "separate HRRRv3 and HRRRv4 strata"
  ],
  "metrics": [
    "mean absolute error",
    "Brier score",
    "paired horizon difference",
    "archive coverage",
    "stadium coverage"
  ],
  "uncertainty": "4,000 deterministic nonparametric bootstrap draws for each error mean and each paired 6-hour-minus-24-hour difference",
  "sensitivities": [
    "HRRRv3 and HRRRv4 reported separately",
    "6-hour and 24-hour horizons reported separately and as paired differences",
    "forecast and stadium coverage disclosed"
  ],
  "withhold_if": [
    "fewer than 1,000 cutoff-safe forecasts",
    "less than 85% of registered archive requests are resolved",
    "either HRRRv3 or HRRRv4 is absent",
    "cutoff integrity or deterministic reproduction fails"
  ],
  "locked_at": "2026-09-03T10:00:00+00:00"
}