{"assessment":{"best_window":{"end":"2026-07-16T21:00Z","end_local":"00:00","hours":1.0,"label":"good","mean_quality":0.7,"start":"2026-07-16T20:00Z","start_local":"23:00"},"cost":{"altitude":0.0,"clouds":4.67,"darkness":3.22,"moon":0.01},"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":"Barely","hourly":[{"alt":null,"cloud":30,"high":23,"iso":"2026-07-16T18:00Z","label":"unusable","low":2,"mid":9,"moon_alt":15,"precip":0.0,"q":0.0,"rh":84,"sky":"civil twilight","temp":14.1,"time":"21:00","wind":4.1},{"alt":null,"cloud":63,"high":18,"iso":"2026-07-16T19:00Z","label":"poor","low":20,"mid":46,"moon_alt":4,"precip":0.2,"q":0.04,"rh":89,"sky":"nautical twilight","temp":12.7,"time":"22:00","wind":5.0},{"alt":null,"cloud":27,"high":25,"iso":"2026-07-16T20:00Z","label":"good","low":2,"mid":2,"moon_alt":-7,"precip":0.4,"q":0.7,"rh":87,"sky":"night","temp":12.8,"time":"23:00","wind":0.5},{"alt":null,"cloud":95,"high":94,"iso":"2026-07-16T21:00Z","label":"unusable","low":27,"mid":3,"moon_alt":-16,"precip":0.0,"q":0.0,"rh":87,"sky":"night","temp":12.2,"time":"00:00","wind":2.4},{"alt":null,"cloud":85,"high":84,"iso":"2026-07-16T22:00Z","label":"unusable","low":6,"mid":2,"moon_alt":-25,"precip":0.0,"q":0.0,"rh":88,"sky":"night","temp":11.9,"time":"01:00","wind":3.9},{"alt":null,"cloud":96,"high":96,"iso":"2026-07-16T23:00Z","label":"unusable","low":2,"mid":7,"moon_alt":-32,"precip":0.0,"q":0.0,"rh":89,"sky":"night","temp":11.8,"time":"02:00","wind":4.4},{"alt":null,"cloud":97,"high":97,"iso":"2026-07-17T00:00Z","label":"unusable","low":2,"mid":20,"moon_alt":-36,"precip":0.0,"q":0.0,"rh":88,"sky":"night","temp":11.5,"time":"03:00","wind":2.7},{"alt":null,"cloud":9,"high":1,"iso":"2026-07-17T01:00Z","label":"marginal","low":5,"mid":4,"moon_alt":-38,"precip":0.0,"q":0.45,"rh":87,"sky":"astronomical twilight","temp":11.7,"time":"04:00","wind":4.4},{"alt":null,"cloud":1,"high":0,"iso":"2026-07-17T02:00Z","label":"poor","low":1,"mid":0,"moon_alt":-36,"precip":0.0,"q":0.15,"rh":88,"sky":"nautical twilight","temp":11.2,"time":"05:00","wind":4.6},{"alt":null,"cloud":2,"high":0,"iso":"2026-07-17T03:00Z","label":"unusable","low":2,"mid":0,"moon_alt":-31,"precip":0.0,"q":0.0,"rh":88,"sky":"civil twilight","temp":10.9,"time":"06:00","wind":4.3}],"peak_quality":0.7,"peak_sky":1.0,"quality_hours":1.35,"reasons":["cloud cover cost 4.7 quality-hours","daylight and twilight cost 3.2 quality-hours"],"reference_hours":4.0,"score":22,"score_astronomy":100,"score_weather":22,"sky_hours":6.02,"verdict":"poor","verdict_astronomy":"good","weather_known":true,"windows":[{"end":"2026-07-16T18:30Z","end_local":"21:30","hours":0.67,"label":"unusable","mean_quality":0.0,"start":"2026-07-16T17:50Z","start_local":"20:50"},{"end":"2026-07-16T20:00Z","end_local":"23:00","hours":1.5,"label":"poor","mean_quality":0.12,"start":"2026-07-16T18:30Z","start_local":"21:30"},{"end":"2026-07-16T21:00Z","end_local":"00:00","hours":1.0,"label":"good","mean_quality":0.7,"start":"2026-07-16T20:00Z","start_local":"23:00"},{"end":"2026-07-17T01:00Z","end_local":"04:00","hours":4.0,"label":"unusable","mean_quality":0.0,"start":"2026-07-16T21:00Z","start_local":"00:00"},{"end":"2026-07-17T01:50Z","end_local":"04:50","hours":0.83,"label":"marginal","mean_quality":0.45,"start":"2026-07-17T01:00Z","start_local":"04:00"},{"end":"2026-07-17T02:30Z","end_local":"05:30","hours":0.67,"label":"poor","mean_quality":0.15,"start":"2026-07-17T01:50Z","start_local":"04:50"},{"end":"2026-07-17T03:05Z","end_local":"06:05","hours":0.58,"label":"unusable","mean_quality":0.0,"start":"2026-07-17T02:30Z","start_local":"05:30"}]},"calculation_version":"2026-10-10.1","forecast":[{"cloud":49,"dark":false,"high":45,"local":"20:00","low":2,"mid":9,"precip":0.0,"rh":70,"temp":16.3,"time":"2026-07-16T17:00Z","wind":6.7},{"cloud":30,"dark":false,"high":23,"local":"21:00","low":2,"mid":9,"precip":0.0,"rh":84,"temp":14.1,"time":"2026-07-16T18:00Z","wind":4.1},{"cloud":63,"dark":false,"high":18,"local":"22:00","low":20,"mid":46,"precip":0.2,"rh":89,"temp":12.7,"time":"2026-07-16T19:00Z","wind":5.0},{"cloud":27,"dark":true,"high":25,"local":"23:00","low":2,"mid":2,"precip":0.4,"rh":87,"temp":12.8,"time":"2026-07-16T20:00Z","wind":0.5},{"cloud":95,"dark":true,"high":94,"local":"00:00","low":27,"mid":3,"precip":0.0,"rh":87,"temp":12.2,"time":"2026-07-16T21:00Z","wind":2.4},{"cloud":85,"dark":true,"high":84,"local":"01:00","low":6,"mid":2,"precip":0.0,"rh":88,"temp":11.9,"time":"2026-07-16T22:00Z","wind":3.9},{"cloud":96,"dark":true,"high":96,"local":"02:00","low":2,"mid":7,"precip":0.0,"rh":89,"temp":11.8,"time":"2026-07-16T23:00Z","wind":4.4},{"cloud":97,"dark":true,"high":97,"local":"03:00","low":2,"mid":20,"precip":0.0,"rh":88,"temp":11.5,"time":"2026-07-17T00:00Z","wind":2.7},{"cloud":9,"dark":false,"high":1,"local":"04:00","low":5,"mid":4,"precip":0.0,"rh":87,"temp":11.7,"time":"2026-07-17T01:00Z","wind":4.4},{"cloud":1,"dark":false,"high":0,"local":"05:00","low":1,"mid":0,"precip":0.0,"rh":88,"temp":11.2,"time":"2026-07-17T02:00Z","wind":4.6},{"cloud":2,"dark":false,"high":0,"local":"06:00","low":2,"mid":0,"precip":0.0,"rh":88,"temp":10.9,"time":"2026-07-17T03:00Z","wind":4.3},{"cloud":3,"dark":false,"high":0,"local":"07:00","low":2,"mid":2,"precip":0.0,"rh":88,"temp":12.3,"time":"2026-07-17T04:00Z","wind":4.2}],"forecast_source":"history","forecast_updated_at":"2026-10-11T16:36:34Z","limits":{"good_alt":30.0,"usable_alt":20.0},"night":{"dark_from":"2026-07-16T19:56:07Z","dark_hours":5.04,"dark_to":"2026-07-17T00:58:33Z","moon":{"illumination":0.088,"phase":"waxing crescent","waxing":true},"moon_free_dark_hours":5.02,"moonrise":"2026-07-17T06:33:12Z","moonset":"2026-07-16T19:20:43Z","sunrise":"2026-07-17T03:01:13Z","sunset":"2026-07-16T17:53:28Z","twilight":{"astronomical":{"end":"2026-07-16T19:56:07Z","start":"2026-07-17T00:58:33Z"},"civil":{"end":"2026-07-16T18:26:21Z","start":"2026-07-17T02:28:19Z"},"nautical":{"end":"2026-07-16T19:07:57Z","start":"2026-07-17T01:46:43Z"}},"window_end":"2026-07-17T09:00:00Z","window_start":"2026-07-16T09:00:00Z"},"night_date":"2026-07-16","site":{"elev_m":1750,"lat":41.693,"lon":24.739,"name":"NAO Rozhen"},"warnings":[]}