Solar forecasts & calibration

SolDial's solar forecasts are tuned to your system, not a generic regional average.

How the forecast is built

1. Physical model — production is modeled with NREL's PVWatts using your system size, location, and (on Pro) per-array tilt and azimuth.
2. Weather adjustment — the model is adjusted with hourly forecasts from Open-Meteo, with the U.S. National Weather Service (NWS) as a fallback.
3. Calibration to your data — once SolDial has enough of your real production history, it performs a one-time calibration so the forecast aligns to how your specific roof actually performs.

Degradation signal

Because calibration happens once, persistent under-performance relative to the calibrated forecast over time becomes a visible signal of panel degradation (separate from normal weather variation).

Forecast pace

On the dashboard, "today's pace" shows how much production is expected by now versus expected for the full day, so you can tell at a glance if you're ahead or behind.