Data Sources

Aurora Forecast UK draws on multiple real-time and reference data feeds to produce location-specific visibility predictions for every city page.

NOAA Space Weather Prediction Center (SWPC)

The primary space weather input comes from NOAA's Space Weather Prediction Center. We ingest the planetary Kp index, OVATION aurora oval model, and solar wind parameters to determine current and forecast geomagnetic activity. These feeds update every few minutes, giving near-real-time awareness of solar-driven aurora conditions.

Kp Index

The Kp index measures global geomagnetic disturbance on a 0-9 scale. Each UK location has a unique Kp threshold based on its magnetic latitude. The further north a city sits on the geomagnetic grid, the lower the Kp needed to see aurora. Shetland and Orkney can see displays at Kp 2-3, while southern England needs Kp 7 or higher.

Cloud Cover

Even strong geomagnetic activity is invisible behind clouds. We pull hourly cloud cover data to give each location an honest assessment of whether the sky is clear enough for aurora viewing. Cloud cover above 80% typically blocks all visibility.

Moon Phase and Illumination

A bright moon washes out faint aurora. We factor in the current moon phase and illumination percentage so that forecasts reflect real-world sky brightness. New moon periods offer the darkest skies and the best chance of spotting subtle aurora colours.

Darkness and Twilight Windows

Aurora is only visible after astronomical twilight ends. For every location we calculate precise sunrise, sunset, and twilight times so the forecast knows when darkness begins. During UK summer months, many northern cities have very short true-darkness windows, which the model accounts for automatically.

Magnetic Latitude

Geographic latitude alone does not determine aurora visibility. The geomagnetic field is tilted, so magnetic latitude — the distance from the magnetic pole — is what matters. We use the latest geomagnetic reference model to assign each of our 54+ UK locations an accurate magnetic latitude, which directly determines its Kp threshold.

Algorithm

Aurora Forecast UK uses a proprietary five-factor algorithm that combines all the data sources above into a single visibility score for each location. The five factors — Kp index, cloud cover, moon illumination, sky darkness, and magnetic latitude — are weighted and blended to produce an overall status (e.g. "Good", "Medium", "Low") and a percentage probability.

The algorithm is calibrated against historical aurora observations and tuned specifically for UK latitudes, where aurora is often lower on the horizon and more sensitive to local conditions than at higher-latitude Nordic sites.

Update Frequency

Space weather data refreshes every 15 minutes, ensuring that sudden geomagnetic storms are reflected in forecasts promptly. Cloud cover updates on an hourly cycle. Moon and darkness calculations are computed at build time and adjusted for the current date.

City pages also display a 12-hour rolling forecast, a 27-day solar rotation outlook, and monthly historical patterns — all updated on the same refresh cycle.

Coverage

Aurora Forecast UK covers all UK regions — Scotland, Northern England, Wales, and Northern Ireland — with 54+ individual locations. From Lerwick in Shetland to London in the south, every city page shows a tailored forecast with local Kp thresholds, real-time conditions, and viewing tips.

Check Your Forecast

Pick a location to see tonight's aurora forecast with live data:

Or use the homepage search to find any of our 54+ UK locations.