A pair of CMEs is heading for Earth, possibly as soon as September 11th. The two solar storm clouds were launched on Sept. 9th and 10th by strong explosions in the magnetic canopy of sunspot AR2158.
Sunspot AR2158 that erupted on Sept. 10th at 17:46 UT, produced an X1.6-class solar flare. X-class flares are big; they are major events that can trigger planet-wide radio blackouts and long-lasting radiation storms. A flash of ultraviolet radiation from the explosion ionized the upper layers of Earth's atmosphere, disturbing HF radio communications for more than an hour. More importantly, the explosion hurled a CME directly toward Earth.
Radio emissions from shock waves at the leading edge of the CME suggest that the cloud tore through the sun's atmosphere at speeds as high as 3750 km/s. That would make this a very fast moving storm, and likely to reach Earth before the weekend. Auroras are definitely in the offing.
Every night, a network of NASA all-sky cameras scans the skies above the United States for meteoritic fireballs. Automated software maintained by NASA's Meteoroid Environment Office calculates their orbits, velocity, penetration depth in Earth's atmosphere and many other characteristics. NOAA forecasters estimate a nearly 80% chance of polar geomagnetic storms on or before Sept. 12th, when the first of the two CMEs could arrive.
Check https://spaceweather.com/ for updates.