Tonight's Decision
A practical aurora forecast for Chicago, USA, built around visibility, cloud risk, and whether it is worth going outside tonight.
Checking Kp, Bz, solar wind, moonlight, and local cloud cover.
Chicago is an aurora viewing location in USA at latitude 41.88 and magnetic latitude 52.0. This page summarizes whether aurora is practical tonight using Kp index, Bz, solar wind speed, moon illumination, cloud cover, and a 0-100 Aurora Visibility Score.
Use the Aurora Visibility Score at the top of this page as the fast decision signal for Chicago. A higher score means stronger geomagnetic activity, better sky clarity, and a more practical chance of visible aurora tonight.
Chicago sits near magnetic latitude 52.0 degrees. Higher-latitude destinations can see aurora at lower Kp values, while lower-latitude cities usually need a stronger geomagnetic storm.
Cloud cover is a major local risk. Even strong aurora activity can be hidden by overcast skies, so clear breaks are often more important for a real viewing decision than small changes in Kp.
The practical viewing window is usually late evening through the early morning hours, with the best chance after full darkness and away from city lights.
Aurora city forecast points
Real-time NOAA Ovation aurora intensity heatmap, refreshed every minute.
