Sunrise Science

What The Scores Mean

🔥 80–100

Exceptional
Set your alarm. Conditions are near-perfect—scattered mid-level clouds, a clear light path out to sea, light westerly winds and a touch of haze. Expect vibrant oranges, pinks, and purples across the sky.

Exceptional

✨ 60–79

Very Good
Worth the early wake-up. Solid colours, good atmosphere. Not flawless, but you won't regret going.

Very Good

😐 40–59

Moderate
Some colour, but nothing spectacular. Decent if you're already awake, probably not worth setting an alarm for.

Moderate

😴 20–39

Poor
Sleep in. Conditions are working against you—mostly grey and flat. Maybe a faint glow, but overall underwhelming.

Poor

😞 0–19

Very Poor
Heavy overcast or terrible atmospheric conditions. You'll see the sky go from dark to slightly less dark. That's about it.

Very Poor

🎯 Built on ECMWF Data

We use the ECMWF (European Centre for Medium-Range Weather Forecasts) model—the most accurate weather forecasting system in the world.

ECMWF is trusted by meteorologists, weather services, and scientific institutions globally. It consistently outperforms other models for medium-range forecasts, which means your sunrise predictions are built on the best atmospheric data available.

The 5 Factors We Track

Every sunrise score is based on these atmospheric conditions

☁️ Cloud Quality

The sweet spot: 30–70% mid-level cloud (2–6km altitude) overhead, with a clear path out to sea for the light to come in under it. Cloud is the canvas: every other factor only changes how well it gets lit. We average five global models (ECMWF, GFS, ICON, UKMO and JMA) and read them at the actual sunrise time, not a fixed hour. Low cloud above 70% acts like a grey ceiling and caps the score at 18/100. A cloud bank 80–160km out along the sunrise bearing blocks the light before it arrives and caps the score at 30, however good the sky overhead looks.

55%

🌫️ Haze

Measured as aerosol optical depth from the Copernicus atmosphere forecast. A modest haze (AOD roughly 0.1–0.25) means there are enough particles to scatter blue light away and leave the reds and oranges. Squeaky-clean air after a strong westerly stays pale; thick smoke or dust mutes everything into a dull orange disc.

20%

💧 Humidity

Humidity between 60–80% creates that atmospheric glow where colours spread across the sky instead of staying concentrated in one spot. Too dry (<50%) and colours lack depth. Too humid (>85%) and you risk fog. It barely moves at dawn on the coast, so it is a small tiebreaker rather than a driver.

5%

💨 Wind

For Sydney's east, wind direction is key. Westerly winds (from inland) = dry, clear air = ideal. Easterly winds (from ocean) = moisture and clouds = less ideal. Wind speed of 5–15 km/h keeps clouds moving and dynamic.

10%

📊 Pressure Trend

Rising pressure means clearing skies. A cold front that passed 12–24 hours ago often leaves behind perfect conditions—rising pressure, scattered mid-level clouds, westerly winds. We track the change over the 12 hours before sunrise: long enough to see a front pass, rather than the daily pressure tide.

10%

Why We Look Along the Light Path

At sunrise the sun is on the horizon, so the light that colours the cloud above the beach has travelled almost horizontally from well out to sea. We sample the forecast at four points: your spot, 20km out (still the sky you can see), and 80km and 160km out along the sunrise bearing.

Why the bearing matters: the sun does not rise due east. In June it comes up about 61° (east-north-east) and in December about 119° (east-south-east). We work out the bearing for each date and lay the sample points along it.

Why the far points matter: low cloud 80–160km out sits exactly where the light has to pass through. If that bank is solid, the sky overhead can be perfect and still stay grey.

How It Works

We pull forecasts from Open-Meteo: five global weather models for cloud, wind and pressure, the Copernicus atmosphere forecast for haze, and the 51-member ECMWF ensemble to see how much the forecasts agree. We read everything at the actual sunrise time, run it through physics-based rules, and give you a score. When the models disagree, the confidence drops and the verdict says so.

Simple rule: Score above 80? Set your alarm. Score below 40? Sleep in.

Special Patterns We Look For

Post-Storm Sunrises

12–24 hours after a cold front passes, conditions often align perfectly: rising pressure, scattered mid-level clouds, westerly winds, and a touch of haze. These are the 90+ score mornings.

Marine Layer Burn-Off

Sometimes heavy low clouds an hour before sunrise drop to <40% by sunrise time. We detect this clearing pattern and adjust the score accordingly.

Limitations (We're Honest)

Microclimates: Localised fog or clouds can form that forecasts miss.

Rapid changes: Weather shifts. We update every 60 minutes, but surprises happen.

Subjective beauty: A 60/100 sunrise might still look incredible to you.

Our accuracy sits around 80% for scores above 70 and below 30. The middle range (40–60) is trickier—conditions can swing either way.