TONIGHT · Mon, Nov 9More reliable forecast
53/100Challenging81% cloud in best window · New Moon (0% illuminated)
Astronomical dusk: 6:07 PM GMT+9
Best 3-hour window: 1 AM–4 AM GMT+9
UPDATED HOURLY
Is Tonight Good for Stargazing in Shakujii Park?
Tonight’s observing conditions and the next seven-night outlook for Shakujii Park, Japan.
TONIGHT · Mon, Nov 9
Shakujii Park
53/100
Challenging conditions for stargazing
Observing night: evening → morning · Asia/Tokyo
Window dates: Nov 10, 2026 01:00 → Nov 10, 2026 04:00
Tonight means the evening of the first date through the following morning, in the city’s time zone—not the night that just ended.
Updated · Time zone: Asia/Tokyo.
The server snapshot is cached for up to one hour.
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 1 AM–4 AM GMT+9, with 81% forecast cloud and 0% illuminated.
Based on the strongest continuous three-hour combination of hourly cloud, visibility and humidity after astronomical dusk.
Tonight, hour by hour
One-hour forecast intervals within astronomical darkness. Highlighted rows are the exact three hours used for tonight’s score. Scores are rounded; their average is rounded again.
Compare the hours
Lines use the same values as the table. Gaps mean unknown data; cloud layers overlap and are not added. The shaded band marks the existing best three-hour window, where available. Asia/Tokyo
- Total cloud
- Low cloud
- Middle cloud
- High cloud
Selected hour: 2026-11-09 19:00
Total cloud: 88% · Low cloud: 88% · Middle cloud: 63% · High cloud: 35%
| Local date / time | Score | Cloud |
|---|---|---|
| Other dark hour | 38/100 | 88% |
| Other dark hour | 35/100 | 91% |
| Other dark hour | 34/100 | 91% |
| Other dark hour | 37/100 | 87% |
| Other dark hour | 50/100 | 68% |
| Other dark hour | 57/100 | 61% |
| Best window | 46/100 | 83% |
| Best window | 54/100 | 84% |
| Best window | 60/100 | 75% |
Why this score?
Largest modeled deductions in the selected window—not a visibility guarantee.
- Clouds: 81% total and 17% high cloud on average.
THIS WEEK
What is the best night for stargazing in Shakujii Park this week?
Wed, Nov 11 has the strongest whole-night average in this seven-night outlook. Its best three-hour window scores 100/100; tonight’s best three-hour window scores 53/100. Check again before leaving.
Whole-night averages
Tonight 46/100 · recommended night Nov 11, 2026: 100/100. This ranking uses all scored dark hours, not each card’s best three hours. Later-night values are indicative, not precise hourly forecasts.
NEXT 7 NIGHTS
Choose a better night to observe
Best upcoming night: Wed, Nov 11 · 100/100
Tue, Nov 10More reliable forecast
100/100Promising8% cloud in best window · New Moon (0% illuminated)
Astronomical dusk: 6:06 PM GMT+9
Best 3-hour window: 8 PM–11 PM GMT+9
Wed, Nov 11More reliable forecast
100/100Promising0% cloud in best window · Waxing Crescent (3% illuminated)
Astronomical dusk: 6:05 PM GMT+9
Best 3-hour window: 7 PM–10 PM GMT+9
Thu, Nov 12Forecast may change
TrendFair55% nightly average cloud · Waxing Crescent (7% illuminated)
Astronomical dusk: 6:05 PM GMT+9
Indicative only — check again closer to the date.
Fri, Nov 13Forecast may change
TrendPromising19% nightly average cloud · Waxing Crescent (14% illuminated)
Astronomical dusk: 6:04 PM GMT+9
Indicative only — check again closer to the date.
Sat, Nov 14Check again closer to the date
TrendPoor99% nightly average cloud · Waxing Crescent (22% illuminated)
Astronomical dusk: 6:03 PM GMT+9
Indicative only — check again closer to the date.
Sun, Nov 15Check again closer to the date
TrendFair45% nightly average cloud · Waxing Crescent (31% illuminated)
Astronomical dusk: 6:03 PM GMT+9
Indicative only — check again closer to the date.
Best-night ranking compares each whole-night average. The first three cards display the best three-hour score; days 4–7 show only an indicative trend. Check again before travelling.
Plan this specific site: Shakujii Park / 石神井公園
A practical Tokyo park option with ponds and uneven tree-lined ground. Urban lighting still limits faint targets; park greenery is not a measured Bortle class or a promise of a clear horizon.
Best suited to
Moon, bright planets and learning the sky—not a dark-sky reserve
Access before weather
The operator lists general park access as always open and admission as free, with exceptions for paid facilities. Service-center and facility hours differ. Check current closure notices and do not enter closed sports facilities or protected pond margins.
A practical session
Visit in daylight first to choose a legal path and an unobstructed patch of sky. Stay clear of water and wildlife, shield direct lamps rather than expecting Milky Way contrast, and plan the last train or parking separately. No public telescope session is promised by this page.
Weather reference point: 35.7390, 139.5975. Tokyo metropolitan open-data reference point near the park service center; not a chosen nighttime viewing position.
Official information checked: · Next source review:
Desk review of official information, not an on-site inspection. Check current closures before travel.
0% illuminated · Check Moon phase and planning
Same three-hour window as the score
Local time
Current surface visibility
CURRENT SNAPSHOT, LAYER BY LAYER
Professional observing conditions
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 16.1 μg/m³ · AOD 0.15
Optics dew indicator
7Timer ASTRO model
Local time
Higher values may reduce transparency
Aurora visibility tonight
Choose a location to load NOAA activity and local conditions.
Find a darker place to observe
Search your destination on a light-pollution map, or browse certified Dark Sky Places. These are external planning resources, not additional live forecast data.
A dark map color does not guarantee clear skies, legal nighttime access or safety. Check the map layer and date, then confirm opening hours, permits, transport and local conditions with the site's operator. These links do not send your coordinates automatically.
Sources and accuracy note
This forecast combines public model data with local astronomical calculations. Missing upstream fields are shown honestly rather than estimated without support.