Aurora Borealis


Where to look:

Start by looking toward the northern horizon.
90% of auroral displays start there. From the northern horizon, a full blown
northern lights display can expand overhead or even into a portion of the
southern sky. There can be a tendency for the light to be most enhanced in the
northwest and northeast quadrants of the sky.

What to look for:

Auroras may initially take on the appearance
of a fog bank on the horizon. One difference between the glowing, foglike cloud
on the horizon is that stars are visible through the haze. With time, the
glowing cloud on the horizon can break into "arcs" of light which appear at
right angles (90-degrees) to the horizon–almost like searchlight beams, but
without the motion associated with such beams. These arcs often begin to pulsate
and feature surges of brighter light through them at irregular intervals.

At the early stage of an auroral display, the glow appears a pale green. But,
reds, blues and greens can follow fairly expeditiously in some instances.

WGN Weather Blog