Goldcast analyses six atmospheric variables from real-time weather model data. Each is weighted by how much it empirically affects the visual quality of a sunrise or sunset. The final score is 0–100.
High Cloud Cover
Cirrus clouds at altitude catch and scatter warm light. Ideal: 20–80%. Too little = featureless sky. Too much = total block.
Low Cloud at Horizon
A bank of low cloud near the horizon blocks the sun at the exact moment it produces the warmest light.
Humidity
Low humidity means cleaner air and more saturated colors. High humidity washes out tones. Above 85% is penalised heavily.
Precipitation & Wind
Active rainfall kills color. Post-storm air is clean with residual cloud texture at altitude — often the most dramatic light of the year.
75–100 — Epic Light. Rare. Multiple factors aligned.
55–74 — Great Conditions. Strong showing expected. Go if you can.
35–54 — Worth Shooting. Modest but workable.
0–34 — Flat Light. Uninspiring sky expected.
Forecasts rely on Open-Meteo weather model data and are inherently probabilistic. Forecasts refresh hourly. Goldcast is a planning tool, not a guarantee.