{"assessment":{"best_window":{"end":"2026-06-16T00:40Z","end_local":"03:40","hours":1.67,"label":"good","mean_quality":0.72,"start":"2026-06-15T23:00Z","start_local":"02:00"},"cost":{"altitude":0.0,"clouds":1.96,"darkness":3.36,"moon":0.0},"formula":"astronomy = 100 * min(1, sky_hours / reference_hours) * peak_sky; overall = astronomy * score_weather / 100 (null when the weather is unknown)","hard_limit":null,"headline":"Possible, with compromises","hourly":[{"alt":null,"cloud":44,"high":44,"iso":"2026-06-15T18:00Z","label":"unusable","low":0,"mid":1,"moon_alt":7,"precip":0.0,"q":0.0,"rh":83,"sky":"civil twilight","temp":12.1,"time":"21:00","wind":5.4},{"alt":null,"cloud":7,"high":6,"iso":"2026-06-15T19:00Z","label":"poor","low":0,"mid":1,"moon_alt":-2,"precip":0.0,"q":0.14,"rh":84,"sky":"nautical twilight","temp":11.4,"time":"22:00","wind":4.6},{"alt":null,"cloud":20,"high":20,"iso":"2026-06-15T20:00Z","label":"marginal","low":0,"mid":0,"moon_alt":-9,"precip":0.0,"q":0.39,"rh":85,"sky":"astronomical twilight","temp":10.7,"time":"23:00","wind":4.2},{"alt":null,"cloud":38,"high":38,"iso":"2026-06-15T21:00Z","label":"marginal","low":0,"mid":0,"moon_alt":-16,"precip":0.0,"q":0.58,"rh":86,"sky":"night","temp":10.1,"time":"00:00","wind":4.1},{"alt":null,"cloud":41,"high":40,"iso":"2026-06-15T22:00Z","label":"marginal","low":0,"mid":0,"moon_alt":-20,"precip":0.0,"q":0.54,"rh":87,"sky":"night","temp":9.5,"time":"01:00","wind":4.2},{"alt":null,"cloud":31,"high":31,"iso":"2026-06-15T23:00Z","label":"good","low":0,"mid":0,"moon_alt":-22,"precip":0.0,"q":0.66,"rh":86,"sky":"night","temp":9.3,"time":"02:00","wind":4.3},{"alt":null,"cloud":17,"high":17,"iso":"2026-06-16T00:00Z","label":"good","low":0,"mid":0,"moon_alt":-21,"precip":0.0,"q":0.81,"rh":89,"sky":"night","temp":8.3,"time":"03:00","wind":5.5},{"alt":null,"cloud":77,"high":77,"iso":"2026-06-16T01:00Z","label":"poor","low":0,"mid":6,"moon_alt":-18,"precip":0.0,"q":0.07,"rh":88,"sky":"astronomical twilight","temp":8.4,"time":"04:00","wind":4.6},{"alt":null,"cloud":88,"high":85,"iso":"2026-06-16T02:00Z","label":"unusable","low":0,"mid":34,"moon_alt":-13,"precip":0.0,"q":0.0,"rh":89,"sky":"nautical twilight","temp":8.3,"time":"05:00","wind":4.2}],"peak_quality":0.81,"peak_sky":1.0,"quality_hours":3.6,"reasons":["daylight and twilight cost 3.4 quality-hours","cloud cover cost 2.0 quality-hours"],"reference_hours":4.0,"score":65,"score_astronomy":100,"score_weather":65,"sky_hours":5.56,"verdict":"marginal","verdict_astronomy":"good","weather_known":true,"windows":[{"end":"2026-06-15T18:35Z","end_local":"21:35","hours":0.67,"label":"unusable","mean_quality":0.0,"start":"2026-06-15T17:55Z","start_local":"20:55"},{"end":"2026-06-15T19:20Z","end_local":"22:20","hours":0.75,"label":"poor","mean_quality":0.1,"start":"2026-06-15T18:35Z","start_local":"21:35"},{"end":"2026-06-15T20:10Z","end_local":"23:10","hours":0.83,"label":"marginal","mean_quality":0.45,"start":"2026-06-15T19:20Z","start_local":"22:20"},{"end":"2026-06-15T21:00Z","end_local":"00:00","hours":0.83,"label":"good","mean_quality":0.78,"start":"2026-06-15T20:10Z","start_local":"23:10"},{"end":"2026-06-15T23:00Z","end_local":"02:00","hours":2.0,"label":"marginal","mean_quality":0.56,"start":"2026-06-15T21:00Z","start_local":"00:00"},{"end":"2026-06-16T00:40Z","end_local":"03:40","hours":1.67,"label":"good","mean_quality":0.72,"start":"2026-06-15T23:00Z","start_local":"02:00"},{"end":"2026-06-16T01:00Z","end_local":"04:00","hours":0.33,"label":"marginal","mean_quality":0.41,"start":"2026-06-16T00:40Z","start_local":"03:40"},{"end":"2026-06-16T02:00Z","end_local":"05:00","hours":1.0,"label":"poor","mean_quality":0.05,"start":"2026-06-16T01:00Z","start_local":"04:00"},{"end":"2026-06-16T02:50Z","end_local":"05:50","hours":0.83,"label":"unusable","mean_quality":0.0,"start":"2026-06-16T02:00Z","start_local":"05:00"}]},"calculation_version":"2026-10-10.1","forecast":[{"cloud":56,"dark":false,"high":55,"local":"20:00","low":0,"mid":2,"precip":0.0,"rh":67,"temp":14.7,"time":"2026-06-15T17:00Z","wind":7.4},{"cloud":44,"dark":false,"high":44,"local":"21:00","low":0,"mid":1,"precip":0.0,"rh":83,"temp":12.1,"time":"2026-06-15T18:00Z","wind":5.4},{"cloud":7,"dark":false,"high":6,"local":"22:00","low":0,"mid":1,"precip":0.0,"rh":84,"temp":11.4,"time":"2026-06-15T19:00Z","wind":4.6},{"cloud":20,"dark":false,"high":20,"local":"23:00","low":0,"mid":0,"precip":0.0,"rh":85,"temp":10.7,"time":"2026-06-15T20:00Z","wind":4.2},{"cloud":38,"dark":true,"high":38,"local":"00:00","low":0,"mid":0,"precip":0.0,"rh":86,"temp":10.1,"time":"2026-06-15T21:00Z","wind":4.1},{"cloud":41,"dark":true,"high":40,"local":"01:00","low":0,"mid":0,"precip":0.0,"rh":87,"temp":9.5,"time":"2026-06-15T22:00Z","wind":4.2},{"cloud":31,"dark":true,"high":31,"local":"02:00","low":0,"mid":0,"precip":0.0,"rh":86,"temp":9.3,"time":"2026-06-15T23:00Z","wind":4.3},{"cloud":17,"dark":true,"high":17,"local":"03:00","low":0,"mid":0,"precip":0.0,"rh":89,"temp":8.3,"time":"2026-06-16T00:00Z","wind":5.5},{"cloud":77,"dark":false,"high":77,"local":"04:00","low":0,"mid":6,"precip":0.0,"rh":88,"temp":8.4,"time":"2026-06-16T01:00Z","wind":4.6},{"cloud":88,"dark":false,"high":85,"local":"05:00","low":0,"mid":34,"precip":0.0,"rh":89,"temp":8.3,"time":"2026-06-16T02:00Z","wind":4.2},{"cloud":91,"dark":false,"high":82,"local":"06:00","low":0,"mid":52,"precip":0.0,"rh":90,"temp":8.5,"time":"2026-06-16T03:00Z","wind":3.7}],"forecast_source":"history","forecast_updated_at":"2026-10-12T08:06:57Z","limits":{"good_alt":30.0,"usable_alt":20.0},"night":{"dark_from":"2026-06-15T20:08:05Z","dark_hours":4.45,"dark_to":"2026-06-16T00:35:11Z","moon":{"illumination":0.011,"phase":"new moon","waxing":true},"moon_free_dark_hours":4.43,"moonrise":"2026-06-16T03:46:22Z","moonset":"2026-06-15T18:47:25Z","sunrise":"2026-06-16T02:45:59Z","sunset":"2026-06-15T17:57:17Z","twilight":{"astronomical":{"end":"2026-06-15T20:08:05Z","start":"2026-06-16T00:35:11Z"},"civil":{"end":"2026-06-15T18:31:27Z","start":"2026-06-16T02:11:49Z"},"nautical":{"end":"2026-06-15T19:15:21Z","start":"2026-06-16T01:27:55Z"}},"window_end":"2026-06-16T09:00:00Z","window_start":"2026-06-15T09:00:00Z"},"night_date":"2026-06-15","site":{"elev_m":1750,"lat":41.693,"lon":24.739,"name":"NAO Rozhen"},"warnings":[]}