{
  "site": {
    "horizonProfile": {
      "observerElevM": 1261,
      "profile": {
        "N": 1.9,
        "NNE": 1.9,
        "NE": 3.2,
        "ENE": 2.3,
        "E": 3.9,
        "ESE": 1.6,
        "SE": 0.3,
        "SSE": 0.8,
        "S": 0.1,
        "SSW": 1.4,
        "SW": 3,
        "WSW": 4.6,
        "W": 5.6,
        "WNW": 4.8,
        "NW": 2.5,
        "NNW": 2
      },
      "south": {
        "worst": 3,
        "mean": 1.1,
        "dueSouth": 0.1
      },
      "core": {
        "coreAltitudeDeg": 17.4,
        "terrainDeg": 3,
        "marginDeg": 14.4,
        "verdict": "clear"
      },
      "computed": "2026-08-25",
      "parts": null
    },
    "id": "wind-cave",
    "name": "Wind Cave National Park",
    "region": "Hot Springs, SD",
    "timezone": "America/Denver",
    "darkSkyPark": false,
    "kind": "area",
    "kindNote": "There is no single spot here, and that is the answer rather than a gap: any designated parking area will do. The figures on this page are computed near the visitor center at the south end of the park, where the rangers run their night programs, so treat them as representative of that end rather than as one pullout.",
    "insideNote": "Any designated parking area. The park runs its night hikes on the Elk Mountain trail, and the campground beside it has sites in both forest and open prairie. Take an open one if the sky is the point. Ranger night program dates are on the park’s own calendar.",
    "mergedFrom": [
      "black-hills-nf"
    ],
    "bortle": null,
    "skyBrightness": null,
    "skyBrightnessFrom": null,
    "darknessNote": "Not measured. Nobody has published a sky-brightness reading for the park that this site can point at. The Park Service is retrofitting lighting in the park towards Dark Sky Park certification, which is an assessment in progress rather than a number.",
    "lat": 43.5567,
    "lng": -103.4783,
    "ground": {
      "darkest": "The darkest place in the Black Hills.",
      "roads": "The roads are very dark and wildlife roams. Be careful.",
      "cell": "For the most part, cell service doesn't work below or above ground. Plan accordingly. Look at the sky.",
      "parking": "Designated places only. No overnight parking.",
      "wildlife": "Beware of the bison.",
      "lightDome": "Hot Springs is the nearest town, and it is the one to think about."
    },
    "groundBy": "Daniel Milks, My XO Adventures.",
    "horizon": null,
    "access": "Wind Cave National Park sits in the southern Black Hills, north of Hot Springs. US Highway 385 and SD Highway 87 run through it. The park is working towards International Dark Sky Park certification and is not certified yet: it has been retrofitting its outdoor lighting, running public education, and working with nearby communities on light pollution. Free ranger night programs run in summer and cover light pollution, Lakota Star Knowledge, full moon hikes and telescope viewing. The guided night hikes go up the Elk Mountain trail. White flashlights and headlamps are not allowed on them and red light is, which is the same reason this site has a red mode. Long pants are recommended for poison ivy and ticks, the trail is steep and rocky and not wheelchair accessible, and nights get cold. There is no overnight parking outside the campground. Elk Mountain Campground has 64 sites, is open year round and around the clock, and is reserved through recreation.gov. It straddles the edge of a ponderosa pine forest and open prairie, and sites sit in both, which matters here: an open prairie site has the horizon a forested one does not. Flush toilets and drinking water run late May through September and fees are half price outside that; vault toilets are year round. There is no cell reception and no internet at the campground. Fires are allowed in the designated rings only and wood collection is not. Backcountry camping is allowed in the northern part of the park with a free permit. Snowfall averages 30 inches a year and periodically closes the park roads, and summer thunderstorms can bring large hail and lightning. The visitor center is at 26611 US Highway 385, Hot Springs SD 57747, and the park telephone is 605 745 4600.",
    "accessUnknown": [],
    "contact": {
      "mail": "26611 US Highway 385, Hot Springs, SD 57747-6027",
      "phone": "605-745-4600",
      "phoneLabel": "Visitor information",
      "fax": "605-745-4207"
    },
    "sources": [
      {
        "label": "NPS, Wind Cave Dark Sky",
        "url": "https://www.nps.gov/wica/learn/nature/dark-sky.htm"
      },
      {
        "label": "NPS, Wind Cave camping",
        "url": "https://www.nps.gov/wica/planyourvisit/campgrounds.htm"
      },
      {
        "label": "NPS, Wind Cave National Park",
        "url": "https://www.nps.gov/wica/index.htm"
      }
    ],
    "verified": "2026-08-25",
    "notes": "Working towards International Dark Sky Park certification, and not certified yet. The Park Service says so itself on its dark sky page, checked 2026-08-25. Badlands, by contrast, was certified in July 2026.",
    "lightSource": {
      "name": "Hot Springs",
      "lat": 43.4319,
      "lng": -103.4744,
      "note": "Coordinates only, and approximate. Used to work out which way the dome sits, not how bright it is. The direction is independently sourced: the Park Service places the park north of Hot Springs."
    }
  },
  "days": 14,
  "generatedAt": "2026-09-18T01:56:11.044Z",
  "weather": {
    "source": "Open-Meteo",
    "error": null,
    "nightsCovered": 14,
    "nightsTotal": 14,
    "note": "Cloud forecast covers every night shown"
  },
  "headline": "Nothing outstanding in the next 14 nights. Wednesday September 23 is the least compromised.",
  "best": {
    "site": "wind-cave",
    "siteName": "Wind Cave National Park",
    "region": "Hot Springs, SD",
    "date": "2026-09-23",
    "score": 60,
    "verdict": "Fair",
    "headline": "Workable. Moon down after 4:28am, clear skies.",
    "headlineLead": "Workable",
    "headlineDetail": "moon down after 4:28am, clear skies",
    "milkyWay": {
      "visible": true,
      "maxAltitudeDeg": 12.4,
      "hoursUseful": 0.48,
      "bestAt": "8:28pm",
      "note": "Milky Way core up to 12.4°, high enough to be worth it for 0h29m"
    },
    "window": {
      "darkFrom": "8:28pm",
      "darkTo": "5:08am",
      "hours": 8.67,
      "bestFrom": "4:28am",
      "bestTo": "5:08am"
    },
    "factors": [
      {
        "key": "cloud",
        "name": "Cloud",
        "score": 100,
        "weight": 32,
        "note": "0% cloud, essentially clear"
      },
      {
        "key": "moon",
        "name": "Moon",
        "score": 21,
        "weight": 26,
        "note": "waxing gibbous at 93%, sets 4:28am, dark after that"
      },
      {
        "key": "darkness",
        "name": "Darkness",
        "score": 96,
        "weight": 16,
        "note": "8h40m of astronomical darkness, 8:28pm–5:08am"
      },
      {
        "key": "transparency",
        "name": "Transparency",
        "score": 9,
        "weight": 10,
        "note": "Dewpoint spread 2.9°C, some haze possible"
      },
      {
        "key": "targets",
        "name": "Targets",
        "score": 42,
        "weight": 16,
        "note": "Milky Way core up to 12.4°, high enough to be worth it for 0h29m"
      }
    ],
    "weatherBacked": true,
    "confidence": "full",
    "dataSources": {
      "astronomy": "SunCalc (local computation)",
      "weather": "Open-Meteo"
    },
    "weekday": "Wednesday",
    "isWeekend": false
  },
  "bestWeekend": {
    "site": "wind-cave",
    "siteName": "Wind Cave National Park",
    "region": "Hot Springs, SD",
    "date": "2026-09-18",
    "score": 47,
    "verdict": "Poor",
    "headline": "Poor conditions. Moon down after 11:08pm, 100% cloud.",
    "headlineLead": "Poor conditions",
    "headlineDetail": "moon down after 11:08pm, 100% cloud",
    "milkyWay": {
      "visible": true,
      "maxAltitudeDeg": 13.1,
      "hoursUseful": 0.65,
      "bestAt": "8:38pm",
      "note": "Milky Way core up to 13.1°, high enough to be worth it for 0h39m"
    },
    "window": {
      "darkFrom": "8:38pm",
      "darkTo": "5:02am",
      "hours": 8.4,
      "bestFrom": "11:08pm",
      "bestTo": "5:02am"
    },
    "factors": [
      {
        "key": "cloud",
        "name": "Cloud",
        "score": 0,
        "weight": 32,
        "note": "100% cloud, mostly high cirrus, thin to the eye but ruinous for photography"
      },
      {
        "key": "moon",
        "name": "Moon",
        "score": 95,
        "weight": 26,
        "note": "first quarter at 54%, sets 11:08pm, dark after that"
      },
      {
        "key": "darkness",
        "name": "Darkness",
        "score": 93,
        "weight": 16,
        "note": "8h24m of astronomical darkness, 8:38pm–5:02am"
      },
      {
        "key": "transparency",
        "name": "Transparency",
        "score": 0,
        "weight": 10,
        "note": "Dewpoint spread 1.3°C, fog or heavy haze likely"
      },
      {
        "key": "targets",
        "name": "Targets",
        "score": 46,
        "weight": 16,
        "note": "Milky Way core up to 13.1°, high enough to be worth it for 0h39m"
      }
    ],
    "weatherBacked": true,
    "confidence": "full",
    "dataSources": {
      "astronomy": "SunCalc (local computation)",
      "weather": "Open-Meteo"
    },
    "weekday": "Friday",
    "isWeekend": true
  },
  "nights": [
    {
      "site": "wind-cave",
      "siteName": "Wind Cave National Park",
      "region": "Hot Springs, SD",
      "date": "2026-09-17",
      "score": 48,
      "verdict": "Poor",
      "headline": "Poor conditions. Moon down after 10:20pm, 99% cloud.",
      "headlineLead": "Poor conditions",
      "headlineDetail": "moon down after 10:20pm, 99% cloud",
      "milkyWay": {
        "visible": true,
        "maxAltitudeDeg": 13.3,
        "hoursUseful": 0.64,
        "bestAt": "8:40pm",
        "note": "Milky Way core up to 13.3°, high enough to be worth it for 0h38m"
      },
      "window": {
        "darkFrom": "8:40pm",
        "darkTo": "5:00am",
        "hours": 8.34,
        "bestFrom": "10:20pm",
        "bestTo": "5:00am"
      },
      "factors": [
        {
          "key": "cloud",
          "name": "Cloud",
          "score": 0,
          "weight": 32,
          "note": "99% cloud, mostly high cirrus, thin to the eye but ruinous for photography"
        },
        {
          "key": "moon",
          "name": "Moon",
          "score": 98,
          "weight": 26,
          "note": "first quarter at 45%, sets 10:20pm, dark after that"
        },
        {
          "key": "darkness",
          "name": "Darkness",
          "score": 93,
          "weight": 16,
          "note": "8h20m of astronomical darkness, 8:40pm–5:00am"
        },
        {
          "key": "transparency",
          "name": "Transparency",
          "score": 0,
          "weight": 10,
          "note": "Dewpoint spread 0.3°C, fog or heavy haze likely"
        },
        {
          "key": "targets",
          "name": "Targets",
          "score": 46,
          "weight": 16,
          "note": "Milky Way core up to 13.3°, high enough to be worth it for 0h38m"
        }
      ],
      "weatherBacked": true,
      "confidence": "full",
      "dataSources": {
        "astronomy": "SunCalc (local computation)",
        "weather": "Open-Meteo"
      },
      "weekday": "Thursday",
      "isWeekend": false
    },
    {
      "site": "wind-cave",
      "siteName": "Wind Cave National Park",
      "region": "Hot Springs, SD",
      "date": "2026-09-18",
      "score": 47,
      "verdict": "Poor",
      "headline": "Poor conditions. Moon down after 11:08pm, 100% cloud.",
      "headlineLead": "Poor conditions",
      "headlineDetail": "moon down after 11:08pm, 100% cloud",
      "milkyWay": {
        "visible": true,
        "maxAltitudeDeg": 13.1,
        "hoursUseful": 0.65,
        "bestAt": "8:38pm",
        "note": "Milky Way core up to 13.1°, high enough to be worth it for 0h39m"
      },
      "window": {
        "darkFrom": "8:38pm",
        "darkTo": "5:02am",
        "hours": 8.4,
        "bestFrom": "11:08pm",
        "bestTo": "5:02am"
      },
      "factors": [
        {
          "key": "cloud",
          "name": "Cloud",
          "score": 0,
          "weight": 32,
          "note": "100% cloud, mostly high cirrus, thin to the eye but ruinous for photography"
        },
        {
          "key": "moon",
          "name": "Moon",
          "score": 95,
          "weight": 26,
          "note": "first quarter at 54%, sets 11:08pm, dark after that"
        },
        {
          "key": "darkness",
          "name": "Darkness",
          "score": 93,
          "weight": 16,
          "note": "8h24m of astronomical darkness, 8:38pm–5:02am"
        },
        {
          "key": "transparency",
          "name": "Transparency",
          "score": 0,
          "weight": 10,
          "note": "Dewpoint spread 1.3°C, fog or heavy haze likely"
        },
        {
          "key": "targets",
          "name": "Targets",
          "score": 46,
          "weight": 16,
          "note": "Milky Way core up to 13.1°, high enough to be worth it for 0h39m"
        }
      ],
      "weatherBacked": true,
      "confidence": "full",
      "dataSources": {
        "astronomy": "SunCalc (local computation)",
        "weather": "Open-Meteo"
      },
      "weekday": "Friday",
      "isWeekend": true
    },
    {
      "site": "wind-cave",
      "siteName": "Wind Cave National Park",
      "region": "Hot Springs, SD",
      "date": "2026-09-19",
      "score": 45,
      "verdict": "Poor",
      "headline": "Poor conditions. Moon down after 12:06am, 100% cloud.",
      "headlineLead": "Poor conditions",
      "headlineDetail": "moon down after 12:06am, 100% cloud",
      "milkyWay": {
        "visible": true,
        "maxAltitudeDeg": 13,
        "hoursUseful": 0.65,
        "bestAt": "8:36pm",
        "note": "Milky Way core up to 13°, high enough to be worth it for 0h39m"
      },
      "window": {
        "darkFrom": "8:36pm",
        "darkTo": "5:03am",
        "hours": 8.45,
        "bestFrom": "12:06am",
        "bestTo": "5:03am"
      },
      "factors": [
        {
          "key": "cloud",
          "name": "Cloud",
          "score": 0,
          "weight": 32,
          "note": "100% cloud, mostly high cirrus, thin to the eye but ruinous for photography"
        },
        {
          "key": "moon",
          "name": "Moon",
          "score": 89,
          "weight": 26,
          "note": "first quarter at 64%, sets 12:06am, dark after that"
        },
        {
          "key": "darkness",
          "name": "Darkness",
          "score": 94,
          "weight": 16,
          "note": "8h27m of astronomical darkness, 8:36pm–5:03am"
        },
        {
          "key": "transparency",
          "name": "Transparency",
          "score": 0,
          "weight": 10,
          "note": "Dewpoint spread 0.6°C, fog or heavy haze likely"
        },
        {
          "key": "targets",
          "name": "Targets",
          "score": 45,
          "weight": 16,
          "note": "Milky Way core up to 13°, high enough to be worth it for 0h39m"
        }
      ],
      "weatherBacked": true,
      "confidence": "full",
      "dataSources": {
        "astronomy": "SunCalc (local computation)",
        "weather": "Open-Meteo"
      },
      "weekday": "Saturday",
      "isWeekend": true
    },
    {
      "site": "wind-cave",
      "siteName": "Wind Cave National Park",
      "region": "Hot Springs, SD",
      "date": "2026-09-20",
      "score": 43,
      "verdict": "Poor",
      "headline": "Poor conditions. Moon down after 1:09am, 100% cloud.",
      "headlineLead": "Poor conditions",
      "headlineDetail": "moon down after 1:09am, 100% cloud",
      "milkyWay": {
        "visible": true,
        "maxAltitudeDeg": 12.8,
        "hoursUseful": 0.64,
        "bestAt": "8:34pm",
        "note": "Milky Way core up to 12.8°, high enough to be worth it for 0h38m"
      },
      "window": {
        "darkFrom": "8:34pm",
        "darkTo": "5:04am",
        "hours": 8.51,
        "bestFrom": "1:09am",
        "bestTo": "5:04am"
      },
      "factors": [
        {
          "key": "cloud",
          "name": "Cloud",
          "score": 0,
          "weight": 32,
          "note": "100% cloud, mostly high cirrus, thin to the eye but ruinous for photography"
        },
        {
          "key": "moon",
          "name": "Moon",
          "score": 80,
          "weight": 26,
          "note": "waxing gibbous at 72%, sets 1:09am, dark after that"
        },
        {
          "key": "darkness",
          "name": "Darkness",
          "score": 95,
          "weight": 16,
          "note": "8h31m of astronomical darkness, 8:34pm–5:04am"
        },
        {
          "key": "transparency",
          "name": "Transparency",
          "score": 0,
          "weight": 10,
          "note": "Dewpoint spread 0.7°C, fog or heavy haze likely"
        },
        {
          "key": "targets",
          "name": "Targets",
          "score": 45,
          "weight": 16,
          "note": "Milky Way core up to 12.8°, high enough to be worth it for 0h38m"
        }
      ],
      "weatherBacked": true,
      "confidence": "full",
      "dataSources": {
        "astronomy": "SunCalc (local computation)",
        "weather": "Open-Meteo"
      },
      "weekday": "Sunday",
      "isWeekend": false
    },
    {
      "site": "wind-cave",
      "siteName": "Wind Cave National Park",
      "region": "Hot Springs, SD",
      "date": "2026-09-21",
      "score": 39,
      "verdict": "Poor",
      "headline": "Poor conditions. Moon down after 2:17am, 96% cloud.",
      "headlineLead": "Poor conditions",
      "headlineDetail": "moon down after 2:17am, 96% cloud",
      "milkyWay": {
        "visible": true,
        "maxAltitudeDeg": 12.7,
        "hoursUseful": 0.65,
        "bestAt": "8:32pm",
        "note": "Milky Way core up to 12.7°, high enough to be worth it for 0h39m"
      },
      "window": {
        "darkFrom": "8:32pm",
        "darkTo": "5:05am",
        "hours": 8.56,
        "bestFrom": "2:17am",
        "bestTo": "5:05am"
      },
      "factors": [
        {
          "key": "cloud",
          "name": "Cloud",
          "score": 0,
          "weight": 32,
          "note": "96% cloud, overcast"
        },
        {
          "key": "moon",
          "name": "Moon",
          "score": 65,
          "weight": 26,
          "note": "waxing gibbous at 80%, sets 2:17am, dark after that"
        },
        {
          "key": "darkness",
          "name": "Darkness",
          "score": 95,
          "weight": 16,
          "note": "8h34m of astronomical darkness, 8:32pm–5:05am"
        },
        {
          "key": "transparency",
          "name": "Transparency",
          "score": 0,
          "weight": 10,
          "note": "Dewpoint spread 0.6°C, fog or heavy haze likely"
        },
        {
          "key": "targets",
          "name": "Targets",
          "score": 45,
          "weight": 16,
          "note": "Milky Way core up to 12.7°, high enough to be worth it for 0h39m"
        }
      ],
      "weatherBacked": true,
      "confidence": "full",
      "dataSources": {
        "astronomy": "SunCalc (local computation)",
        "weather": "Open-Meteo"
      },
      "weekday": "Monday",
      "isWeekend": false
    },
    {
      "site": "wind-cave",
      "siteName": "Wind Cave National Park",
      "region": "Hot Springs, SD",
      "date": "2026-09-22",
      "score": 34,
      "verdict": "Poor",
      "headline": "Poor conditions. Moon down after 3:20am, 93% cloud.",
      "headlineLead": "Poor conditions",
      "headlineDetail": "moon down after 3:20am, 93% cloud",
      "milkyWay": {
        "visible": true,
        "maxAltitudeDeg": 12.5,
        "hoursUseful": 0.49,
        "bestAt": "8:30pm",
        "note": "Milky Way core up to 12.5°, high enough to be worth it for 0h29m"
      },
      "window": {
        "darkFrom": "8:30pm",
        "darkTo": "5:07am",
        "hours": 8.62,
        "bestFrom": "3:20am",
        "bestTo": "5:07am"
      },
      "factors": [
        {
          "key": "cloud",
          "name": "Cloud",
          "score": 0,
          "weight": 32,
          "note": "93% cloud, mostly high cirrus, thin to the eye but ruinous for photography"
        },
        {
          "key": "moon",
          "name": "Moon",
          "score": 45,
          "weight": 26,
          "note": "waxing gibbous at 88%, sets 3:20am, dark after that"
        },
        {
          "key": "darkness",
          "name": "Darkness",
          "score": 96,
          "weight": 16,
          "note": "8h37m of astronomical darkness, 8:30pm–5:07am"
        },
        {
          "key": "transparency",
          "name": "Transparency",
          "score": 0,
          "weight": 10,
          "note": "Dewpoint spread 1.0°C, fog or heavy haze likely"
        },
        {
          "key": "targets",
          "name": "Targets",
          "score": 42,
          "weight": 16,
          "note": "Milky Way core up to 12.5°, high enough to be worth it for 0h29m"
        }
      ],
      "weatherBacked": true,
      "confidence": "full",
      "dataSources": {
        "astronomy": "SunCalc (local computation)",
        "weather": "Open-Meteo"
      },
      "weekday": "Tuesday",
      "isWeekend": false
    },
    {
      "site": "wind-cave",
      "siteName": "Wind Cave National Park",
      "region": "Hot Springs, SD",
      "date": "2026-09-23",
      "score": 60,
      "verdict": "Fair",
      "headline": "Workable. Moon down after 4:28am, clear skies.",
      "headlineLead": "Workable",
      "headlineDetail": "moon down after 4:28am, clear skies",
      "milkyWay": {
        "visible": true,
        "maxAltitudeDeg": 12.4,
        "hoursUseful": 0.48,
        "bestAt": "8:28pm",
        "note": "Milky Way core up to 12.4°, high enough to be worth it for 0h29m"
      },
      "window": {
        "darkFrom": "8:28pm",
        "darkTo": "5:08am",
        "hours": 8.67,
        "bestFrom": "4:28am",
        "bestTo": "5:08am"
      },
      "factors": [
        {
          "key": "cloud",
          "name": "Cloud",
          "score": 100,
          "weight": 32,
          "note": "0% cloud, essentially clear"
        },
        {
          "key": "moon",
          "name": "Moon",
          "score": 21,
          "weight": 26,
          "note": "waxing gibbous at 93%, sets 4:28am, dark after that"
        },
        {
          "key": "darkness",
          "name": "Darkness",
          "score": 96,
          "weight": 16,
          "note": "8h40m of astronomical darkness, 8:28pm–5:08am"
        },
        {
          "key": "transparency",
          "name": "Transparency",
          "score": 9,
          "weight": 10,
          "note": "Dewpoint spread 2.9°C, some haze possible"
        },
        {
          "key": "targets",
          "name": "Targets",
          "score": 42,
          "weight": 16,
          "note": "Milky Way core up to 12.4°, high enough to be worth it for 0h29m"
        }
      ],
      "weatherBacked": true,
      "confidence": "full",
      "dataSources": {
        "astronomy": "SunCalc (local computation)",
        "weather": "Open-Meteo"
      },
      "weekday": "Wednesday",
      "isWeekend": false
    },
    {
      "site": "wind-cave",
      "siteName": "Wind Cave National Park",
      "region": "Hot Springs, SD",
      "date": "2026-09-24",
      "score": 43,
      "verdict": "Poor",
      "headline": "Poor conditions. Moon up all night, 40% cloud.",
      "headlineLead": "Poor conditions",
      "headlineDetail": "moon up all night, 40% cloud",
      "milkyWay": {
        "visible": true,
        "maxAltitudeDeg": 12.2,
        "hoursUseful": 0.48,
        "bestAt": "8:26pm",
        "note": "Milky Way core up to 12.2°, high enough to be worth it for 0h29m"
      },
      "window": {
        "darkFrom": "8:26pm",
        "darkTo": "5:09am",
        "hours": 8.73,
        "bestFrom": "8:26pm",
        "bestTo": "5:09am"
      },
      "factors": [
        {
          "key": "cloud",
          "name": "Cloud",
          "score": 48,
          "weight": 32,
          "note": "40% cloud, mostly high cirrus, thin to the eye but ruinous for photography"
        },
        {
          "key": "moon",
          "name": "Moon",
          "score": 0,
          "weight": 26,
          "note": "full moon at 97%, up the whole window, washing out faint targets"
        },
        {
          "key": "darkness",
          "name": "Darkness",
          "score": 97,
          "weight": 16,
          "note": "8h44m of astronomical darkness, 8:26pm–5:09am"
        },
        {
          "key": "transparency",
          "name": "Transparency",
          "score": 56,
          "weight": 10,
          "note": "Dewpoint spread 7.6°C, some haze possible"
        },
        {
          "key": "targets",
          "name": "Targets",
          "score": 41,
          "weight": 16,
          "note": "Milky Way core up to 12.2°, high enough to be worth it for 0h29m"
        }
      ],
      "weatherBacked": true,
      "confidence": "full",
      "dataSources": {
        "astronomy": "SunCalc (local computation)",
        "weather": "Open-Meteo"
      },
      "weekday": "Thursday",
      "isWeekend": false
    },
    {
      "site": "wind-cave",
      "siteName": "Wind Cave National Park",
      "region": "Hot Springs, SD",
      "date": "2026-09-25",
      "score": 42,
      "verdict": "Poor",
      "headline": "Poor conditions. Moon up all night, 34% cloud.",
      "headlineLead": "Poor conditions",
      "headlineDetail": "moon up all night, 34% cloud",
      "milkyWay": {
        "visible": true,
        "maxAltitudeDeg": 12.1,
        "hoursUseful": 0.49,
        "bestAt": "8:24pm",
        "note": "Milky Way core up to 12.1°, high enough to be worth it for 0h29m"
      },
      "window": {
        "darkFrom": "8:24pm",
        "darkTo": "5:10am",
        "hours": 8.78,
        "bestFrom": "8:24pm",
        "bestTo": "5:10am"
      },
      "factors": [
        {
          "key": "cloud",
          "name": "Cloud",
          "score": 64,
          "weight": 32,
          "note": "34% cloud cover, 6% of it high"
        },
        {
          "key": "moon",
          "name": "Moon",
          "score": 0,
          "weight": 26,
          "note": "full moon at 100%, up the whole window, washing out faint targets"
        },
        {
          "key": "darkness",
          "name": "Darkness",
          "score": 98,
          "weight": 16,
          "note": "8h47m of astronomical darkness, 8:24pm–5:10am"
        },
        {
          "key": "transparency",
          "name": "Transparency",
          "score": 0,
          "weight": 10,
          "note": "Dewpoint spread 1.7°C, fog or heavy haze likely"
        },
        {
          "key": "targets",
          "name": "Targets",
          "score": 41,
          "weight": 16,
          "note": "Milky Way core up to 12.1°, high enough to be worth it for 0h29m"
        }
      ],
      "weatherBacked": true,
      "confidence": "full",
      "dataSources": {
        "astronomy": "SunCalc (local computation)",
        "weather": "Open-Meteo"
      },
      "weekday": "Friday",
      "isWeekend": true
    },
    {
      "site": "wind-cave",
      "siteName": "Wind Cave National Park",
      "region": "Hot Springs, SD",
      "date": "2026-09-26",
      "score": 39,
      "verdict": "Poor",
      "headline": "Poor conditions. Moon up all night, 65% cloud.",
      "headlineLead": "Poor conditions",
      "headlineDetail": "moon up all night, 65% cloud",
      "milkyWay": {
        "visible": true,
        "maxAltitudeDeg": 11.9,
        "hoursUseful": 0.48,
        "bestAt": "8:22pm",
        "note": "Milky Way core up to 11.9°, high enough to be worth it for 0h29m"
      },
      "window": {
        "darkFrom": "8:22pm",
        "darkTo": "5:12am",
        "hours": 8.83,
        "bestFrom": "8:22pm",
        "bestTo": "5:12am"
      },
      "factors": [
        {
          "key": "cloud",
          "name": "Cloud",
          "score": 20,
          "weight": 32,
          "note": "65% cloud, mostly high cirrus, thin to the eye but ruinous for photography"
        },
        {
          "key": "moon",
          "name": "Moon",
          "score": 0,
          "weight": 26,
          "note": "full moon at 100%, up the whole window, washing out faint targets"
        },
        {
          "key": "darkness",
          "name": "Darkness",
          "score": 98,
          "weight": 16,
          "note": "8h50m of astronomical darkness, 8:22pm–5:12am"
        },
        {
          "key": "transparency",
          "name": "Transparency",
          "score": 99,
          "weight": 10,
          "note": "Dewpoint spread 11.9°C, dry and steady air"
        },
        {
          "key": "targets",
          "name": "Targets",
          "score": 40,
          "weight": 16,
          "note": "Milky Way core up to 11.9°, high enough to be worth it for 0h29m"
        }
      ],
      "weatherBacked": true,
      "confidence": "full",
      "dataSources": {
        "astronomy": "SunCalc (local computation)",
        "weather": "Open-Meteo"
      },
      "weekday": "Saturday",
      "isWeekend": true
    },
    {
      "site": "wind-cave",
      "siteName": "Wind Cave National Park",
      "region": "Hot Springs, SD",
      "date": "2026-09-27",
      "score": 56,
      "verdict": "Fair",
      "headline": "Workable. Moon up all night, 21% cloud.",
      "headlineLead": "Workable",
      "headlineDetail": "moon up all night, 21% cloud",
      "milkyWay": {
        "visible": true,
        "maxAltitudeDeg": 11.7,
        "hoursUseful": 0.32,
        "bestAt": "8:20pm",
        "note": "Milky Way core up to 11.7°, high enough to be worth it for 0h19m"
      },
      "window": {
        "darkFrom": "8:20pm",
        "darkTo": "5:13am",
        "hours": 8.89,
        "bestFrom": "8:20pm",
        "bestTo": "5:13am"
      },
      "factors": [
        {
          "key": "cloud",
          "name": "Cloud",
          "score": 76,
          "weight": 32,
          "note": "21% cloud cover, 10% of it high"
        },
        {
          "key": "moon",
          "name": "Moon",
          "score": 0,
          "weight": 26,
          "note": "full moon at 97%, up the whole window, washing out faint targets"
        },
        {
          "key": "darkness",
          "name": "Darkness",
          "score": 99,
          "weight": 16,
          "note": "8h53m of astronomical darkness, 8:20pm–5:13am"
        },
        {
          "key": "transparency",
          "name": "Transparency",
          "score": 98,
          "weight": 10,
          "note": "Dewpoint spread 11.8°C, dry and steady air"
        },
        {
          "key": "targets",
          "name": "Targets",
          "score": 38,
          "weight": 16,
          "note": "Milky Way core up to 11.7°, high enough to be worth it for 0h19m"
        }
      ],
      "weatherBacked": true,
      "confidence": "full",
      "dataSources": {
        "astronomy": "SunCalc (local computation)",
        "weather": "Open-Meteo"
      },
      "weekday": "Sunday",
      "isWeekend": false
    },
    {
      "site": "wind-cave",
      "siteName": "Wind Cave National Park",
      "region": "Hot Springs, SD",
      "date": "2026-09-28",
      "score": 45,
      "verdict": "Poor",
      "headline": "Poor conditions. Moon up all night, 27% cloud.",
      "headlineLead": "Poor conditions",
      "headlineDetail": "moon up all night, 27% cloud",
      "milkyWay": {
        "visible": true,
        "maxAltitudeDeg": 11.6,
        "hoursUseful": 0.33,
        "bestAt": "8:18pm",
        "note": "Milky Way core up to 11.6°, high enough to be worth it for 0h20m"
      },
      "window": {
        "darkFrom": "8:18pm",
        "darkTo": "5:14am",
        "hours": 8.94,
        "bestFrom": "8:18pm",
        "bestTo": "5:14am"
      },
      "factors": [
        {
          "key": "cloud",
          "name": "Cloud",
          "score": 73,
          "weight": 32,
          "note": "27% cloud cover, 1% of it high"
        },
        {
          "key": "moon",
          "name": "Moon",
          "score": 0,
          "weight": 26,
          "note": "waning gibbous at 92%, up the whole window, washing out faint targets"
        },
        {
          "key": "darkness",
          "name": "Darkness",
          "score": 99,
          "weight": 16,
          "note": "8h56m of astronomical darkness, 8:18pm–5:14am"
        },
        {
          "key": "transparency",
          "name": "Transparency",
          "score": 5,
          "weight": 10,
          "note": "Dewpoint spread 2.5°C, some haze possible"
        },
        {
          "key": "targets",
          "name": "Targets",
          "score": 37,
          "weight": 16,
          "note": "Milky Way core up to 11.6°, high enough to be worth it for 0h20m"
        }
      ],
      "weatherBacked": true,
      "confidence": "full",
      "dataSources": {
        "astronomy": "SunCalc (local computation)",
        "weather": "Open-Meteo"
      },
      "weekday": "Monday",
      "isWeekend": false
    },
    {
      "site": "wind-cave",
      "siteName": "Wind Cave National Park",
      "region": "Hot Springs, SD",
      "date": "2026-09-29",
      "score": 22,
      "verdict": "Not worth the drive",
      "headline": "Not worth the drive. Moon up all night, 95% cloud.",
      "headlineLead": "Not worth the drive",
      "headlineDetail": "moon up all night, 95% cloud",
      "milkyWay": {
        "visible": true,
        "maxAltitudeDeg": 11.4,
        "hoursUseful": 0.33,
        "bestAt": "8:16pm",
        "note": "Milky Way core up to 11.4°, high enough to be worth it for 0h20m"
      },
      "window": {
        "darkFrom": "8:16pm",
        "darkTo": "5:15am",
        "hours": 8.99,
        "bestFrom": "8:16pm",
        "bestTo": "5:15am"
      },
      "factors": [
        {
          "key": "cloud",
          "name": "Cloud",
          "score": 0,
          "weight": 32,
          "note": "95% cloud, overcast"
        },
        {
          "key": "moon",
          "name": "Moon",
          "score": 0,
          "weight": 26,
          "note": "waning gibbous at 85%, up the whole window, washing out faint targets"
        },
        {
          "key": "darkness",
          "name": "Darkness",
          "score": 100,
          "weight": 16,
          "note": "8h60m of astronomical darkness, 8:16pm–5:15am"
        },
        {
          "key": "transparency",
          "name": "Transparency",
          "score": 0,
          "weight": 10,
          "note": "Dewpoint spread 1.9°C, fog or heavy haze likely"
        },
        {
          "key": "targets",
          "name": "Targets",
          "score": 37,
          "weight": 16,
          "note": "Milky Way core up to 11.4°, high enough to be worth it for 0h20m"
        }
      ],
      "weatherBacked": true,
      "confidence": "full",
      "dataSources": {
        "astronomy": "SunCalc (local computation)",
        "weather": "Open-Meteo"
      },
      "weekday": "Tuesday",
      "isWeekend": false
    },
    {
      "site": "wind-cave",
      "siteName": "Wind Cave National Park",
      "region": "Hot Springs, SD",
      "date": "2026-09-30",
      "score": 23,
      "verdict": "Not worth the drive",
      "headline": "Not worth the drive. Moon up after 8:29pm, 99% cloud.",
      "headlineLead": "Not worth the drive",
      "headlineDetail": "moon up after 8:29pm, 99% cloud",
      "milkyWay": {
        "visible": true,
        "maxAltitudeDeg": 11.2,
        "hoursUseful": 0.32,
        "bestAt": "8:14pm",
        "note": "Milky Way core up to 11.2°, high enough to be worth it for 0h19m"
      },
      "window": {
        "darkFrom": "8:14pm",
        "darkTo": "5:17am",
        "hours": 9.05,
        "bestFrom": "8:14pm",
        "bestTo": "8:29pm"
      },
      "factors": [
        {
          "key": "cloud",
          "name": "Cloud",
          "score": 0,
          "weight": 32,
          "note": "99% cloud, mostly high cirrus, thin to the eye but ruinous for photography"
        },
        {
          "key": "moon",
          "name": "Moon",
          "score": 1,
          "weight": 26,
          "note": "waning gibbous at 76%, rises 8:29pm, dark before that"
        },
        {
          "key": "darkness",
          "name": "Darkness",
          "score": 100,
          "weight": 16,
          "note": "9h03m of astronomical darkness, 8:14pm–5:17am"
        },
        {
          "key": "transparency",
          "name": "Transparency",
          "score": 7,
          "weight": 10,
          "note": "Dewpoint spread 2.7°C, some haze possible"
        },
        {
          "key": "targets",
          "name": "Targets",
          "score": 36,
          "weight": 16,
          "note": "Milky Way core up to 11.2°, high enough to be worth it for 0h19m"
        }
      ],
      "weatherBacked": true,
      "confidence": "full",
      "dataSources": {
        "astronomy": "SunCalc (local computation)",
        "weather": "Open-Meteo"
      },
      "weekday": "Wednesday",
      "isWeekend": false
    }
  ]
}