Dark Sky Tonight | Light Pollution, Moon & Cloud Cover

Source health

Ready

Click a U.S. location to estimate tonight's viewing context.

100 representative U.S. places tonight

Loading…

Ranked only among 100 representative Census places, not every possible observing site.

MitchellCo Tonight Score v2 uses NASA annual radiance, the best 3-hour NWS cloud window during astronomical darkness, Moon altitude/illumination, and total dark hours. Method, sources & licenses.

Tonight at selected location

—

Select a location.

Conditions

Latitude—Longitude—Cloud cover—Forecast time—Moon illuminated—Moon phase—

How to read the map

NASA VIIRS Black Marble is a 2016 annual nighttime-light composite. Brighter areas are a proxy for artificial/upward-emitted light, not direct sky brightness or a current light-pollution reading. Cloud cover is the NWS forecast-grid value nearest approximately 10 PM local solar time. Moon illumination is calculated locally for that target time.

Selected-location context

Derived, not official. A map click still uses the lightweight cloud + Moon context score shown above. The 100-place ranking is separate: it uses numerical VNP46A4 radiance plus cloud, Moon altitude/illumination and astronomical-dark hours from the prebuilt snapshot.

Sources & vintage

NASA Worldview / GIBS: Suomi NPP/VIIRS via NASA Earth Observatory, Black Marble annual 2016 reference imagery. NOAA/NWS: forecast-grid sky cover with source forecast time. Basemap: © OpenStreetMap contributors. Rendering: Leaflet 1.9.4.

Full data sources, licenses, EULA notes & citations

MitchellCo-derived viewing context is not a NASA or NOAA/NWS product and does not imply endorsement. Internet delivery is not guaranteed.

© 2026 MitchellCo · Product blog Inc.