32% cloud in best window · Waxing Gibbous (95% illuminated)
Astronomical dusk: 7:01 PM GMT+9
Best 3-hour window: 8 PM–11 PM GMT+9
UPDATED HOURLY
Tonight’s observing conditions and the next seven-night outlook for Tokyo, Japan.
Updated · Time zone: Asia/Tokyo.
TONIGHT · Thu, Sep 24
Challenging conditions for stargazing
The score includes forecast sky conditions and a Moon-phase proxy after astronomical dusk. Moonrise, local light pollution and site access are not scored; bright planets and faint deep-sky targets have different requirements.
Is tonight good for stargazing? Challenging. The strongest three-hour window is 8 PM–11 PM GMT+9, with 32% forecast cloud and 95% illuminated.
Based on the strongest continuous three-hour combination of hourly cloud, visibility and humidity after astronomical dusk.
THIS WEEK
Tonight is currently the highest-rated option in the next seven nights at 46/100. Forecasts can change, so check again before leaving.
NEXT 7 NIGHTS
Best upcoming night: Thu, Sep 24 · 46/100
32% cloud in best window · Waxing Gibbous (95% illuminated)
Astronomical dusk: 7:01 PM GMT+9
Best 3-hour window: 8 PM–11 PM GMT+9
38% cloud in best window · Full Moon (99% illuminated)
Astronomical dusk: 7:00 PM GMT+9
Best 3-hour window: 10 PM–1 AM GMT+9
68% cloud in best window · Full Moon (100% illuminated)
Astronomical dusk: 6:58 PM GMT+9
Best 3-hour window: 9 PM–12 AM GMT+9
99% nightly average cloud · Full Moon (99% illuminated)
Astronomical dusk: 6:57 PM GMT+9
Trend only — check again closer to the date.
100% nightly average cloud · Waning Gibbous (96% illuminated)
Astronomical dusk: 6:55 PM GMT+9
Trend only — check again closer to the date.
98% nightly average cloud · Waning Gibbous (91% illuminated)
Astronomical dusk: 6:54 PM GMT+9
Trend only — check again closer to the date.
79% nightly average cloud · Waning Gibbous (84% illuminated)
Astronomical dusk: 6:52 PM GMT+9
Trend only — check again closer to the date.
The first three nights include hourly detail. Days 4–7 are more likely to change, so check again before travelling.
95% illuminated · check local moonrise and moonset
Same three-hour window as the score
Local time
Current surface visibility
CURRENT SNAPSHOT, LAYER BY LAYER
These are current forecast fields; the tonight score above uses the best three-hour window. Compare both with local conditions before travelling.
Near-surface layer
Middle atmosphere
Thin cloud can spread skyglow
PM2.5 30.3 μg/m³ · AOD 0.24
Optics dew indicator
7Timer ASTRO model
Local time
Higher values may reduce transparency
Tokyo’s bright urban sky and humid air often limit faint deep-sky contrast. Clear nights can still suit the Moon, planets and bright constellations; for fainter targets, pay particular attention to transparency, high cloud and direct local lighting.
HUMAN-REVIEWED OPTIONS
These are planning candidates, not guarantees of darkness, safety or nighttime access. A site may close before the forecast’s best window; compare its posted hours with the recommended time.
Good for: Beginner sessions, Moon and bright planets
Its large lawn and open view across Chofu Airport have been used for official seasonal stargazing events.
Before you go: Treat this as an event-based recommendation. Confirm the park’s latest event notice and nighttime access before visiting.
Good for: Community telescope sessions and bright targets
The open sky above the central pond supports a recurring volunteer-led public observing program.
Before you go: City light remains strong and event arrangements change. Check the official park news rather than assuming telescopes are present nightly.
Good for: Moon, Jupiter and bright constellations
An easy central option with an open lawn; the park has held official sessions with temporary light reduction.
Before you go: Best used during an announced observing event. Ordinary nights are bright and may not offer the same lighting or access arrangement.
Official information reviewed August 20, 2026. Always confirm current access, weather, transport and local safety conditions before leaving.
The displayed server snapshot is cached for up to one hour.
This forecast combines public model data with local astronomical calculations. Missing upstream fields are shown honestly rather than estimated without support.