{"assessment":{"best_window":{"end":"2026-06-28T00:00Z","end_local":"03:00","hours":3.75,"label":"marginal","mean_quality":0.46,"start":"2026-06-27T20:15Z","start_local":"23:15"},"cost":{"altitude":0.0,"clouds":1.13,"darkness":3.37,"moon":2.45},"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":8,"high":0,"iso":"2026-06-27T18:00Z","label":"unusable","low":7,"mid":1,"moon_alt":12,"precip":0.0,"q":0.0,"rh":77,"sky":"civil twilight","temp":14.0,"time":"21:00","wind":11.8},{"alt":null,"cloud":18,"high":0,"iso":"2026-06-27T19:00Z","label":"poor","low":18,"mid":0,"moon_alt":17,"precip":0.0,"q":0.06,"rh":86,"sky":"nautical twilight","temp":12.6,"time":"22:00","wind":8.1},{"alt":null,"cloud":9,"high":0,"iso":"2026-06-27T20:00Z","label":"poor","low":9,"mid":0,"moon_alt":20,"precip":0.0,"q":0.22,"rh":93,"sky":"astronomical twilight","temp":11.7,"time":"23:00","wind":6.6},{"alt":null,"cloud":5,"high":0,"iso":"2026-06-27T21:00Z","label":"marginal","low":5,"mid":0,"moon_alt":20,"precip":0.0,"q":0.46,"rh":97,"sky":"night","temp":10.7,"time":"00:00","wind":5.6},{"alt":null,"cloud":4,"high":0,"iso":"2026-06-27T22:00Z","label":"marginal","low":4,"mid":0,"moon_alt":18,"precip":0.0,"q":0.48,"rh":99,"sky":"night","temp":10.0,"time":"01:00","wind":5.1},{"alt":null,"cloud":16,"high":0,"iso":"2026-06-27T23:00Z","label":"marginal","low":16,"mid":0,"moon_alt":13,"precip":0.0,"q":0.43,"rh":99,"sky":"night","temp":9.4,"time":"02:00","wind":5.6},{"alt":null,"cloud":94,"high":0,"iso":"2026-06-28T00:00Z","label":"unusable","low":94,"mid":0,"moon_alt":7,"precip":0.0,"q":0.0,"rh":100,"sky":"night","temp":8.7,"time":"03:00","wind":6.9},{"alt":null,"cloud":100,"high":0,"iso":"2026-06-28T01:00Z","label":"unusable","low":100,"mid":0,"moon_alt":-1,"precip":0.0,"q":0.0,"rh":100,"sky":"astronomical twilight","temp":8.5,"time":"04:00","wind":8.7},{"alt":null,"cloud":95,"high":0,"iso":"2026-06-28T02:00Z","label":"unusable","low":95,"mid":0,"moon_alt":-10,"precip":0.0,"q":0.0,"rh":99,"sky":"nautical twilight","temp":8.1,"time":"05:00","wind":9.0}],"peak_quality":0.5,"peak_sky":0.6,"quality_hours":1.96,"reasons":["daylight and twilight cost 3.4 quality-hours","moonlight cost 2.5 quality-hours","cloud cover cost 1.1 quality-hours"],"reference_hours":4.0,"score":29,"score_astronomy":46,"score_weather":63,"sky_hours":3.09,"verdict":"poor","verdict_astronomy":"marginal","weather_known":true,"windows":[{"end":"2026-06-27T18:35Z","end_local":"21:35","hours":0.67,"label":"unusable","mean_quality":0.0,"start":"2026-06-27T17:55Z","start_local":"20:55"},{"end":"2026-06-27T20:15Z","end_local":"23:15","hours":1.67,"label":"poor","mean_quality":0.14,"start":"2026-06-27T18:35Z","start_local":"21:35"},{"end":"2026-06-28T00:00Z","end_local":"03:00","hours":3.75,"label":"marginal","mean_quality":0.46,"start":"2026-06-27T20:15Z","start_local":"23:15"},{"end":"2026-06-28T02:50Z","end_local":"05:50","hours":2.83,"label":"unusable","mean_quality":0.0,"start":"2026-06-28T00:00Z","start_local":"03:00"}]},"calculation_version":"2026-10-10.1","forecast":[{"cloud":12,"dark":false,"high":0,"local":"20:00","low":10,"mid":2,"precip":0.0,"rh":72,"temp":15.7,"time":"2026-06-27T17:00Z","wind":13.5},{"cloud":8,"dark":false,"high":0,"local":"21:00","low":7,"mid":1,"precip":0.0,"rh":77,"temp":14.0,"time":"2026-06-27T18:00Z","wind":11.8},{"cloud":18,"dark":false,"high":0,"local":"22:00","low":18,"mid":0,"precip":0.0,"rh":86,"temp":12.6,"time":"2026-06-27T19:00Z","wind":8.1},{"cloud":9,"dark":false,"high":0,"local":"23:00","low":9,"mid":0,"precip":0.0,"rh":93,"temp":11.7,"time":"2026-06-27T20:00Z","wind":6.6},{"cloud":5,"dark":true,"high":0,"local":"00:00","low":5,"mid":0,"precip":0.0,"rh":97,"temp":10.7,"time":"2026-06-27T21:00Z","wind":5.6},{"cloud":4,"dark":true,"high":0,"local":"01:00","low":4,"mid":0,"precip":0.0,"rh":99,"temp":10.0,"time":"2026-06-27T22:00Z","wind":5.1},{"cloud":16,"dark":true,"high":0,"local":"02:00","low":16,"mid":0,"precip":0.0,"rh":99,"temp":9.4,"time":"2026-06-27T23:00Z","wind":5.6},{"cloud":94,"dark":true,"high":0,"local":"03:00","low":94,"mid":0,"precip":0.0,"rh":100,"temp":8.7,"time":"2026-06-28T00:00Z","wind":6.9},{"cloud":100,"dark":false,"high":0,"local":"04:00","low":100,"mid":0,"precip":0.0,"rh":100,"temp":8.5,"time":"2026-06-28T01:00Z","wind":8.7},{"cloud":95,"dark":false,"high":0,"local":"05:00","low":95,"mid":0,"precip":0.0,"rh":99,"temp":8.1,"time":"2026-06-28T02:00Z","wind":9.0},{"cloud":94,"dark":false,"high":0,"local":"06:00","low":94,"mid":0,"precip":0.0,"rh":100,"temp":7.7,"time":"2026-06-28T03:00Z","wind":9.4}],"forecast_source":"history","forecast_updated_at":"2026-10-12T02:50:17Z","limits":{"good_alt":30.0,"usable_alt":20.0},"night":{"dark_from":"2026-06-27T20:10:18Z","dark_hours":4.47,"dark_to":"2026-06-28T00:38:16Z","moon":{"illumination":0.96,"phase":"waxing gibbous","waxing":true},"moon_free_dark_hours":0.0,"moonrise":"2026-06-27T16:26:46Z","moonset":"2026-06-28T00:50:40Z","sunrise":"2026-06-28T02:48:51Z","sunset":"2026-06-27T17:59:43Z","twilight":{"astronomical":{"end":"2026-06-27T20:10:18Z","start":"2026-06-28T00:38:16Z"},"civil":{"end":"2026-06-27T18:33:51Z","start":"2026-06-28T02:14:43Z"},"nautical":{"end":"2026-06-27T19:17:41Z","start":"2026-06-28T01:30:53Z"}},"window_end":"2026-06-28T09:00:00Z","window_start":"2026-06-27T09:00:00Z"},"night_date":"2026-06-27","site":{"elev_m":1750,"lat":41.693,"lon":24.739,"name":"NAO Rozhen"},"warnings":[]}