0% cloud in best window · Waxing Gibbous (95% illuminated)
Astronomical dusk: 8:48 PM GMT+1
Best 3-hour window: 9 PM–12 AM GMT+1
UPDATED HOURLY
Tonight’s observing conditions and the next seven-night outlook for London, United Kingdom.
Updated · Time zone: Europe/London.
TONIGHT · Thu, Sep 24
Fair 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? Fair. The strongest three-hour window is 9 PM–12 AM GMT+1, with 0% 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 69/100. Forecasts can change, so check again before leaving.
NEXT 7 NIGHTS
Best upcoming night: Thu, Sep 24 · 69/100
0% cloud in best window · Waxing Gibbous (95% illuminated)
Astronomical dusk: 8:48 PM GMT+1
Best 3-hour window: 9 PM–12 AM GMT+1
82% cloud in best window · Full Moon (99% illuminated)
Astronomical dusk: 8:45 PM GMT+1
Best 3-hour window: 9 PM–12 AM GMT+1
85% cloud in best window · Full Moon (100% illuminated)
Astronomical dusk: 8:43 PM GMT+1
Best 3-hour window: 4 AM–7 AM GMT+1
100% nightly average cloud · Full Moon (99% illuminated)
Astronomical dusk: 8:40 PM GMT+1
Trend only — check again closer to the date.
76% nightly average cloud · Waning Gibbous (96% illuminated)
Astronomical dusk: 8:38 PM GMT+1
Trend only — check again closer to the date.
100% nightly average cloud · Waning Gibbous (91% illuminated)
Astronomical dusk: 8:35 PM GMT+1
Trend only — check again closer to the date.
61% nightly average cloud · Waning Gibbous (84% illuminated)
Astronomical dusk: 8:33 PM GMT+1
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 4.2 μg/m³ · AOD 0.20
Optics dew indicator
7Timer ASTRO model
Local time
Higher values may reduce transparency
London’s skyglow and frequent layered cloud can reduce contrast even when surface visibility looks acceptable. Summer nights are also short at this latitude, so astronomical darkness and high cloud deserve as much attention as the headline cloud percentage.
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: Moon, planets and bright constellations
Elevated open areas offer broad sky views while remaining reachable by public transport.
Before you go: Use open, familiar areas and review current Heath rules. The constabulary’s published patrol hours do not mean every area is equally suitable late at night.
Good for: Meteor showers and wider-field observing
London’s largest Royal Park provides extensive open grassland and more separation from the city centre.
Before you go: Pedestrian gates are normally open 24/7, but night closures apply during deer culls and vehicle gates close at dusk. Check current notices.
Good for: Bright deep-sky targets and meteor watching
Large, flat open spaces can provide wider horizons than central London parks.
Before you go: Pedestrian gates are normally open 24/7, with seasonal deer-cull exceptions; vehicle gates close at dusk. Avoid disturbing wildlife.
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.