Aurora Borealis in Castlereagh
United Kingdom · 54.57°, -5.88° · geomagnetic 57.3° · needs Kp 7
Tonight's aurora forecast for Castlereagh
36%
Peak chance of a visible display tonight, from the same model the Revon app runs. Castlereagh needs Kp 7 to see anything at all, and tonight the forecast peaks at Kp 4.9. Short of the threshold, which is what most nights look like here.
Get the full 30-night forecast in Revon
Updated 2026-09-08 10:36 UTC
Local aurora guide for Castlereagh
Castlereagh generally needs planetary Kp 7 before the aurora borealis reaches the local sky. Historical Kp and darkness data produce about 2.6 viable nights a year across 10.0 years of records.
The strongest historical overlap of darkness and activity occurs in September, August and November. From May through July, limited astronomical darkness can prevent viewing.
The central sky is approximately Bortle 8. The supplied darker-sky reference is 21 km north-north-east at Bortle 4.
Aurorasaurus recorded 256 verified reports within 300 km of Castlereagh between 2015-01-01 and 2016-12-31. These records describe past observations, not tonight's prediction.
Sources: Revon analysis of NOAA planetary Kp · Solar declination and hour-angle calculation · Falchi 2016 World Atlas of artificial night sky brightness · Aurorasaurus verified positive reports
Know when it is worth going outside
Revon watches the Castlereagh forecast and pushes an alert when the odds for tonight clear your threshold — no checking, no guessing.
Nearby towns
Forecasts for places within reach of Castlereagh.