WASHINGTON (AP) — Northerners thawing out from a bitter freeze may get rewarded with shimmering northern lights the next couple days.

Federal space weather forecaster Joe Kunches said the sun shot out a strong solar flare late Tuesday, which should arrive at Earth early Thursday. It should shake up Earth’s magnetic field and expand the Aurora Borealis south, possibly as far south as Colorado and central Illinois. He said best viewing would probably be Thursday evening, weather permitting.

The University of Alaska’s Geophysical Institute predicts much of Canada and the northern fringes of the U.S. should see the northern lights. Chicago, Boston, Cleveland, Seattle and Des Moines might see the shimmering colors low on the horizon.

The solar storm is already diverting airline flights around the poles and may disrupt GPS devices Thursday.