Northern lights may be visible in 16 US states tonight as several CMEs race toward Earth

Auroras may be visible from Alaska to Illinois tonight as several coronal mass ejections are forecast to impact within the next couple of days.

Several coronal mass ejections (CMEs) are currently hurtling toward Earth, with the first due to arrive within 24 hours. The impacts could ring Earth's magnetic field like a bell, triggering moderate (G2) geomagnetic storm conditions and pushing the northern lights farther south than usual.

NOAA space weather forecasters have issued a G2 (moderate) geomagnetic storm watch for March 19 (UTC) — which translates to late March 18 in North America — when the main bulk of the first CME is expected to arrive. G2 conditions could come about if the CME's magnetic field is favorably aligned, or "geoeffective," allowing auroras to dip into mid-latitudes. There is also a chance that strong (G3 conditions) could develop, which would see northern lights spread even farther south.