StarCast · Night Sky Forecast

Stargazing Forecast Tonight

StarCast delivers a stargazing forecast for any location: cloud cover, atmospheric transparency, moon phase, and Bortle class scored into one number. Know before dark whether tonight is worth it.

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What goes into a real stargazing forecast

Four Variables in One Score

A stargazing forecast isn't a cloud cover percentage. It's the intersection of cloud cover, transparency, moon phase, and your location's baseline sky darkness — all weighted against each other. StarCast does that math and gives you a single 0–100 score for tonight.

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Cloud Cover Score

StarCast scores cloud cover in bands — not as a linear scale. Under 10% is near-perfect. 10–30% is good. 30–50% is marginal. Above 50%, consistent viewing becomes unreliable. The score reflects real-world impact, not just a raw percentage.

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Atmospheric Transparency

The sky can be clear and still look milky from humidity or aerosols. Transparency is the difference between a night where you can count 500 stars and one where you can count 50. StarCast pulls transparency data and factors it directly into the score.

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Moon Phase and Rise/Set Timing

The moon is the biggest single variable for deep-sky viewing and Milky Way photography. StarCast shows tonight's moon illumination percentage, rise time, and set time — so you know exactly how long your dark window is before or after moonrise.

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Bortle Class for Your Location

Your sky's baseline darkness sets the ceiling on what conditions can deliver. StarCast loads your Bortle class from your GPS coordinates automatically. A high-scoring night at Bortle 2 and a high-scoring night at Bortle 7 are completely different experiences — the score accounts for this.

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Tonight's Forecast Delivered to Your Phone

StarCast push alerts notify you when a high-scoring night is forecast at your saved locations. You set the threshold. When conditions clear that bar, your phone tells you — well before dark. Exclusive to the iOS app.

Common Questions

What is a stargazing forecast?

A forecast specifically for night sky conditions: cloud cover, transparency, moon phase, and Bortle class scored together. StarCast is built around this — unlike weather apps that show generic cloud percentage without transparency or moon data. Free on web, push alerts in the iOS app.

How far out can I forecast stargazing conditions?

StarCast shows a 3-day outlook. Cloud cover forecasts are reasonably reliable within 48 hours; beyond that, treat it as a trend indicator. Transparency forecasts are slightly less reliable at range but still useful for trip planning around moon phase windows.

What StarCast score means a good stargazing night?

60+ is a solid night for casual stargazing and most astrophotography. 75+ is excellent. 80+ is rare and typically means new moon, low humidity, post-frontal air, and clear skies — the kind of night you remember.

Does StarCast work for any location?

Yes. Search any location by name or use your current GPS coordinates. StarCast loads Bortle class data for your exact coordinates so the score reflects your specific sky, not a regional average.

What is LightCast StarCast?

StarCast is a night sky conditions tool that scores cloud cover, transparency, moon phase, and Bortle class into a single forecast score. Free on web at lightcastsuite.com/starcast, push notifications in the LightCast iOS app. $2.99/month after a 7-day free trial.

Tonight's stargazing forecast for any location.

Cloud cover · Transparency · Moon phase · Bortle class
Push alerts · Saved locations · 3-day outlook

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