Pre-specified analysis plan: multi-horizon solar radiation forecasting at 11 USCRN stations (seven models, 1–24 h)

This record time-stamps the analysis plan of a forecasting study before any test-set metric of the final models was computed. The study compares seven models (LightGBM, XGBoost, CatBoost, Prophet, NeuralProphet, LSTM–CNN, PatchTST) for hourly global irradiance forecasts at 1, 3, 6, 12 and 24 h ahead at 11 U.S. Climate Reference Network stations (5 climate groups, 8 Köppen–Geiger subtypes; data 2008–2025; test period 2023–2025). The plan fixes the evaluation rows, metrics, skill-score references, ranking and tie rules, cross-station aggregation, horizon analysis and the full list of sensitivity analyses, including Amendment 1. The file P5_analysis_plan.sha256 contains the SHA-256 of the plan; anyone can verify it with `sha256sum P5_analysis_plan.md`.