Colorado Aurora & Sunset Alerts

Never miss the night the northern lights reach Colorado, or the evening the whole sky lights up. I watch the forecasts so you don't have to, and you only get an email when it's worth grabbing your camera.

How the alerts work

Aurora alerts come from NOAA's Space Weather Prediction Center planetary K-index (Kp) forecast, checked every afternoon and again in the evening. Colorado is far enough south that it takes a strong storm, about Kp 7 or higher, before the aurora shows up here, usually as a red or pink glow low on the northern horizon that cameras catch better than eyes. You get one email per storm, not a stream of them.

Sunset alerts use the same cloud-layer forecast as Planning Your Shot: the best sunsets need high and mid clouds to catch the color with a fairly clear western horizon so the light can reach them. An alert goes out around 1–2pm when several spots across the state score "Great," and never more than about twice a week.

Forecasts are forecasts. Clouds and space weather both change quickly, so check the live pages before a long drive.