Aurora Signal

Reads NOAA's live aurora model rather than guessing from the Kp index alone — and works out which dark spot is worth the drive tonight.

Most aurora apps hand you four dashboards and leave you to work it out. Aurora Signal gives you one number: the chance of seeing the northern lights tonight, where you actually are.

It reads NOAA's live OVATION aurora model for the sky above you, then weighs it against your cloud forecast, your light pollution, the moon, and whether it will even get properly dark. If any one of those rules the night out, the number says so. This app is as willing to tell you to stay home as it is to send you out.

FREE • Tonight's probability, with the reasoning behind it • The hour worth going out — the clearest hour around solar midnight • The Kp your location actually needs, from geomagnetic latitude rather than a line on a map • Conditions at a glance: Kp, cloud cover, light pollution, moon phase • Live aurora webcams • A photo log for the nights you catch one

AURORA PRO • Nearby dark spots — real places with drive times, ranked by how dark they are, how far you'd travel, and whether the drive moves you toward the aurora oval • Live aurora map with NOAA's probability overlay • Home screen widget • Three-day forecast and a longer outlook • Custom alert threshold

WHY THE NUMBER IS DIFFERENT The auroral oval is centred on the geomagnetic pole, not the geographic one, and the two sit about ten degrees apart. Seattle is at 47°N but 53° geomagnetic — which is why it sees aurora that Moscow, further north, does not. Aurora Signal works in geomagnetic latitude, so the threshold it gives you is the one that applies where you're standing.

BUILT HONESTLY No account. No tracking. No analytics. The app contains no third-party code at all. Your coordinates go to Open-Meteo for a cloud forecast and nowhere else — light pollution is read from a map bundled inside the app, and space weather is identical for everyone.

Aurora Pro is available as a $9.99 annual subscription or a $24.99 one-time lifetime unlock. Subscriptions renew automatically unless cancelled at least 24 hours before the period ends.

Data from the NOAA Space Weather Prediction Center and Open-Meteo.

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