{"assessment":{"best_window":{"end":"2026-08-31T19:10Z","end_local":"22:10","hours":0.58,"label":"good","mean_quality":0.62,"start":"2026-08-31T18:35Z","start_local":"21:35"},"cost":{"altitude":0.0,"clouds":0.03,"darkness":2.58,"moon":4.42},"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":1,"high":0,"iso":"2026-08-31T17:00Z","label":"unusable","low":0,"mid":1,"moon_alt":-13,"precip":0.0,"q":0.0,"rh":67,"sky":"civil twilight","temp":15.0,"time":"20:00","wind":1.8},{"alt":null,"cloud":0,"high":0,"iso":"2026-08-31T18:00Z","label":"marginal","low":0,"mid":0,"moon_alt":-3,"precip":0.0,"q":0.5,"rh":66,"sky":"astronomical twilight","temp":14.4,"time":"21:00","wind":2.8},{"alt":null,"cloud":1,"high":0,"iso":"2026-08-31T19:00Z","label":"good","low":0,"mid":1,"moon_alt":8,"precip":0.0,"q":0.61,"rh":62,"sky":"night","temp":14.5,"time":"22:00","wind":1.8},{"alt":null,"cloud":2,"high":0,"iso":"2026-08-31T20:00Z","label":"marginal","low":0,"mid":2,"moon_alt":19,"precip":0.0,"q":0.54,"rh":62,"sky":"night","temp":14.2,"time":"23:00","wind":1.8},{"alt":null,"cloud":1,"high":0,"iso":"2026-08-31T21:00Z","label":"marginal","low":0,"mid":1,"moon_alt":30,"precip":0.0,"q":0.49,"rh":64,"sky":"night","temp":13.4,"time":"00:00","wind":3.8},{"alt":null,"cloud":1,"high":0,"iso":"2026-08-31T22:00Z","label":"marginal","low":0,"mid":1,"moon_alt":40,"precip":0.0,"q":0.44,"rh":65,"sky":"night","temp":12.9,"time":"01:00","wind":2.7},{"alt":null,"cloud":0,"high":0,"iso":"2026-08-31T23:00Z","label":"marginal","low":0,"mid":0,"moon_alt":50,"precip":0.0,"q":0.4,"rh":68,"sky":"night","temp":12.3,"time":"02:00","wind":2.8},{"alt":null,"cloud":0,"high":0,"iso":"2026-09-01T00:00Z","label":"marginal","low":0,"mid":0,"moon_alt":58,"precip":0.0,"q":0.37,"rh":73,"sky":"night","temp":11.0,"time":"03:00","wind":2.7},{"alt":null,"cloud":0,"high":0,"iso":"2026-09-01T01:00Z","label":"marginal","low":0,"mid":0,"moon_alt":62,"precip":0.0,"q":0.36,"rh":76,"sky":"night","temp":11.1,"time":"04:00","wind":2.6},{"alt":null,"cloud":0,"high":0,"iso":"2026-09-01T02:00Z","label":"marginal","low":0,"mid":0,"moon_alt":60,"precip":0.0,"q":0.37,"rh":79,"sky":"night","temp":11.0,"time":"05:00","wind":3.0},{"alt":null,"cloud":0,"high":0,"iso":"2026-09-01T03:00Z","label":"poor","low":0,"mid":0,"moon_alt":54,"precip":0.0,"q":0.06,"rh":81,"sky":"nautical twilight","temp":10.9,"time":"06:00","wind":3.1}],"peak_quality":0.64,"peak_sky":0.64,"quality_hours":3.89,"reasons":["moonlight cost 4.4 quality-hours","daylight and twilight cost 2.6 quality-hours"],"reference_hours":4.0,"score":63,"score_astronomy":63,"score_weather":99,"sky_hours":3.92,"verdict":"marginal","verdict_astronomy":"marginal","weather_known":true,"windows":[{"end":"2026-08-31T17:25Z","end_local":"20:25","hours":0.5,"label":"unusable","mean_quality":0.0,"start":"2026-08-31T16:55Z","start_local":"19:55"},{"end":"2026-08-31T18:00Z","end_local":"21:00","hours":0.58,"label":"poor","mean_quality":0.15,"start":"2026-08-31T17:25Z","start_local":"20:25"},{"end":"2026-08-31T18:35Z","end_local":"21:35","hours":0.58,"label":"marginal","mean_quality":0.43,"start":"2026-08-31T18:00Z","start_local":"21:00"},{"end":"2026-08-31T19:10Z","end_local":"22:10","hours":0.58,"label":"good","mean_quality":0.62,"start":"2026-08-31T18:35Z","start_local":"21:35"},{"end":"2026-09-01T02:10Z","end_local":"05:10","hours":7.0,"label":"marginal","mean_quality":0.44,"start":"2026-08-31T19:10Z","start_local":"22:10"},{"end":"2026-09-01T03:20Z","end_local":"06:20","hours":1.17,"label":"poor","mean_quality":0.12,"start":"2026-09-01T02:10Z","start_local":"05:10"},{"end":"2026-09-01T03:50Z","end_local":"06:50","hours":0.5,"label":"unusable","mean_quality":0.0,"start":"2026-09-01T03:20Z","start_local":"06:20"}]},"calculation_version":"2026-10-10.1","forecast":[{"cloud":7,"dark":false,"high":1,"local":"19:00","low":5,"mid":2,"precip":0.0,"rh":53,"temp":17.9,"time":"2026-08-31T16:00Z","wind":6.5},{"cloud":1,"dark":false,"high":0,"local":"20:00","low":0,"mid":1,"precip":0.0,"rh":67,"temp":15.0,"time":"2026-08-31T17:00Z","wind":1.8},{"cloud":0,"dark":false,"high":0,"local":"21:00","low":0,"mid":0,"precip":0.0,"rh":66,"temp":14.4,"time":"2026-08-31T18:00Z","wind":2.8},{"cloud":1,"dark":true,"high":0,"local":"22:00","low":0,"mid":1,"precip":0.0,"rh":62,"temp":14.5,"time":"2026-08-31T19:00Z","wind":1.8},{"cloud":2,"dark":true,"high":0,"local":"23:00","low":0,"mid":2,"precip":0.0,"rh":62,"temp":14.2,"time":"2026-08-31T20:00Z","wind":1.8},{"cloud":1,"dark":true,"high":0,"local":"00:00","low":0,"mid":1,"precip":0.0,"rh":64,"temp":13.4,"time":"2026-08-31T21:00Z","wind":3.8},{"cloud":1,"dark":true,"high":0,"local":"01:00","low":0,"mid":1,"precip":0.0,"rh":65,"temp":12.9,"time":"2026-08-31T22:00Z","wind":2.7},{"cloud":0,"dark":true,"high":0,"local":"02:00","low":0,"mid":0,"precip":0.0,"rh":68,"temp":12.3,"time":"2026-08-31T23:00Z","wind":2.8},{"cloud":0,"dark":true,"high":0,"local":"03:00","low":0,"mid":0,"precip":0.0,"rh":73,"temp":11.0,"time":"2026-09-01T00:00Z","wind":2.7},{"cloud":0,"dark":true,"high":0,"local":"04:00","low":0,"mid":0,"precip":0.0,"rh":76,"temp":11.1,"time":"2026-09-01T01:00Z","wind":2.6},{"cloud":0,"dark":true,"high":0,"local":"05:00","low":0,"mid":0,"precip":0.0,"rh":79,"temp":11.0,"time":"2026-09-01T02:00Z","wind":3.0},{"cloud":0,"dark":false,"high":0,"local":"06:00","low":0,"mid":0,"precip":0.0,"rh":81,"temp":10.9,"time":"2026-09-01T03:00Z","wind":3.1},{"cloud":0,"dark":false,"high":0,"local":"07:00","low":0,"mid":0,"precip":0.0,"rh":81,"temp":10.9,"time":"2026-09-01T04:00Z","wind":3.4}],"forecast_source":"history","forecast_updated_at":"2026-10-10T17:48:56Z","limits":{"good_alt":30.0,"usable_alt":20.0},"night":{"dark_from":"2026-08-31T18:34:51Z","dark_hours":7.56,"dark_to":"2026-09-01T02:08:09Z","moon":{"illumination":0.847,"phase":"waning gibbous","waxing":false},"moon_free_dark_hours":0.0,"moonrise":"2026-08-31T18:17:21Z","moonset":"2026-09-01T08:16:39Z","sunrise":"2026-09-01T03:46:47Z","sunset":"2026-08-31T16:56:18Z","twilight":{"astronomical":{"end":"2026-08-31T18:34:51Z","start":"2026-09-01T02:08:09Z"},"civil":{"end":"2026-08-31T17:24:52Z","start":"2026-09-01T03:18:11Z"},"nautical":{"end":"2026-08-31T17:59:01Z","start":"2026-09-01T02:44:00Z"}},"window_end":"2026-09-01T09:00:00Z","window_start":"2026-08-31T09:00:00Z"},"night_date":"2026-08-31","site":{"elev_m":1750,"lat":41.693,"lon":24.739,"name":"NAO Rozhen"},"warnings":[]}
