Skynuvio Open map

Sky forecast for astronomers

Watch the stars, not the clouds

Hourly cloud cover by layer, humidity and dew, the Moon and light pollution — all on one map. In under a minute, you’ll know if tonight will be clear and where to go for dark skies.

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  • Free
  • No sign-up
  • 3-night forecast
TonightLake District
Bortle 4
8.4/10

Excellent night

Clear from 22:00 to 03:00. Moonset at 21:50.

Clear sky by hour22–03
Clouds
6%
Humidity
71%
Moon
12%
Wind
7 km/h

Dew after 02:00 — switch on your dew heater

Why

Weather apps don’t answer the question that matters

Will the Andromeda Galaxy be visible at 2 a.m.? A “sun behind a cloud” icon won’t tell you.

Weather forecast
“Partly cloudy, overnight low 4°”
Skynuvio
“Clear from 22:00 to 03:00, the Moon won’t get in the way, dew after 2 a.m.”

  • Clouds by layer

    Low, mid and high clouds, shown separately for every hour of the night.

  • Dew and wind

    A heads-up before your optics fog up or gusts start shaking the telescope.

  • Moon and darkness

    Moon phase, moonrise and moonset, and when astronomical night begins and ends.

  • Light pollution

    The Bortle class of your sky and a color-coded light pollution map, from class 1 to 9.

Who it’s for

For everyone waiting for a clear night

From a first telescope in the backyard to astrophotography trips far from home.

  • Backyard observers

    Decide whether to set up in the yard or drive out of town.

  • Astrophotographers

    Find a window with no clouds and no Moon before you pack your gear.

  • Event chasers

    Meteor showers, comets, eclipses — never miss a clear night.

  • Astronomy clubs and schools

    Schedule field trips and public star parties on the best nights.

  • Travelers

    Pick a campsite under the stars, not under the glow of a city.

  • Beginners

    See the Milky Way for the first time and know where to go to find it.

Why Skynuvio

Easier than a weather app and five open tabs

Usually you have to cross-check a weather forecast, an astronomy service, a Moon calendar and a light pollution map. Here it’s all in one window — plus a single, clear night score from 0 to 10.

Skynuvio compared with a regular weather forecast and separate astronomy services
FeatureRegular weatherAstro servicesSkynuvio
Clouds by layer: low, mid and high
Hourly forecast focused on the night
Dew and optics fogging risk
Bortle light pollution on the same map
Cloud map with an hourly time slider
Night score 0–10 and the best window
Plain-language summary of each night
Free, no sign-up

availablepartial or not everywherenot availableCompared with the typical features of services in each category.

Sky map

The whole night on one map

Clouds by layer for any hour over the next three days, humidity, wind, temperature and Bortle classes. Tap a spot to get a report on the night.

  1. Find a placeType a town or tap the map.
  2. Check the scoreA 0–10 rating and an hour-by-hour breakdown. With Plus — a short AI verdict.
  3. Pick your windowMove the time slider to see where the sky is clear.
Open map
Skynuvio sky map with clouds, the Bortle light pollution legend and a tooltip for a spot

Moon calendar

When are the darkest nights?

The Moon is the brightest light in the night sky. Save galaxies and nebulae for the nights around the new Moon — here are the next 30.

    Dark night: the Moon is less than 25% litPhase at 23:00 in your time zone

    Plans

    The map is free for everyone. AI comes with Plus or Ultra

    The map, night reports and forecasts are free, no card needed. AI costs real money to run, so the AI verdict and the Ask AI chat come with Plus and Ultra.

    Free

    Forever

    $0/month

    Everything you need to plan a night.

    • Sky map: clouds by layer, humidity, wind, temperature
    • Bortle light pollution map
    • Night score and hourly report
    • 3-night forecast, no sign-up for the map
    • AI verdict for every night
    • Ask AI chat
    • Supports development and the phone app
    • Double the support for the project
    Use for free

    Plus

    Supports the project

    $5/month

    All of Free, plus the AI verdict and the Ask AI chat.

    • Sky map: clouds by layer, humidity, wind, temperature
    • Bortle light pollution map
    • Night score and hourly report
    • 3-night forecast, no sign-up for the map
    • AI verdict for every night
    • Ask AI chat, 60 AI requests a day
    • Supports development and the phone app
    • Double the support for the project
    Get Plus

    Ultra

    Biggest support

    $10/month

    Everything in Plus, more AI requests and double the support.

    • Sky map: clouds by layer, humidity, wind, temperature
    • Bortle light pollution map
    • Night score and hourly report
    • 3-night forecast, no sign-up for the map
    • AI verdict for every night
    • Ask AI chat, 200 AI requests a day
    • Supports development and the phone app
    • Double the support for the project
    Get Ultra

    The free version isn’t a trial: the map and night reports stay free, with no time limit. Plus and Ultra add AI, which costs money to run. Cancel anytime.

    App

    Coming to your phone — with your help

    Everything on the website, plus what you need in the field, far from the city.

    • “Clear tonight” alertsA notification when a good night is coming to your favorite spots.
    • Red night modeA screen that won’t ruin your dark adaptation.
    • WidgetTonight’s score right on your home screen.
    • Saved placesYour cabin, a field out of town, the club observatory.
    Download on theApp Store GET IT ONGoogle Play

    Honest note: Skynuvio is a small independent project with no funding. The app will only happen with your support — every Plus or Ultra subscription brings it closer.

    FAQ

    Quick answers

    Where does the data come from?

    Weather forecasts come from global and regional weather models via the open Open-Meteo service. Light pollution is estimated from NASA satellite images of night lights (VIIRS Black Marble). Sun and Moon positions are calculated with astronomical formulas.

    How accurate is the cloud forecast?

    Good for the next 24 hours; after that, accuracy drops, as with any forecast. That’s why we show three nights ahead and recommend checking again on the day you plan to observe.

    What is the Bortle scale?

    Nine classes of night sky brightness: 1 is a pristine dark sky far from any city, 9 is a big-city center. The lower the class, the more stars you’ll see. We estimate it for every spot from satellite data.

    Is it free?

    Yes. The website, the map and night reports are free and don’t require sign-up. AI features cost money to run, so they come with the paid plans: Skynuvio Plus ($5/month) adds the AI verdict and the Ask AI chat, and Skynuvio Ultra ($10/month) adds more AI requests and twice the support.

    When will the app be out?

    Apps for iOS and Android are planned, but Skynuvio has no funding, so the app depends on your support through Skynuvio Plus and Ultra. In the meantime, the sky map already works in your browser, including on your phone.

    It might be clear tonight

    Open the map, tap your spot — and in a second you’ll know if it’s worth taking the telescope out.

    Open map