"Kp index"

‘Strong’ Northern Lights Alert For 20 States On Monday As CME Strikes

The northern lights may be visible overnight from up to 20 northern U.S. states on Monday, June 8, through Tuesday, June 9, according to NOA...

Northern Lights Could Return Tonight — Here’s Where

Northern lights dazzled 23 U.S. states overnight, and forecasters say auroras could return tonight as lingering solar storm effects continue...