Residents of northern U.S. states may see the aurora borealis tonight and into the early hours of Tuesday, May 19, 2026 [1, 2].

This celestial event matters because powerful solar disturbances can push the auroral oval southward, making the northern lights visible to millions of people who live far outside the typical polar viewing zones.

Forecasters said that up to three glancing coronal mass ejections (CMEs) could trigger geomagnetic storms through May 20 [1]. These solar events, combined with high-speed solar wind from a coronal hole, create the conditions necessary for the aurora to appear [1, 3].

There is some variation in the expected reach of the display. Some reports suggest the lights could be visible in 10 states [3], while other estimates place the number at 16 [2] or as many as 20 U.S. states [2].

The intensity of the geomagnetic storm is also a point of varying reports. Some data indicates a minor G1 storm [3], while other forecasters said the disturbance was upgraded to a G2 geomagnetic storm after observing an Earth-directed CME [2].

For those hoping to catch a glimpse of the lights, the best viewing window is expected to be between 10 p.m. and 2 a.m. local time [4]. Observers are encouraged to look toward the northern horizon in areas with dark skies and minimal light pollution.

Solar activity of this nature is driven by the sun's magnetic cycles. When CMEs—large bursts of plasma and magnetic fields—hit Earth's magnetosphere, they cause the geomagnetic storms that result in the vibrant colors of the aurora borealis [1].

“Northern lights may be visible in 16 US states tonight.”

The discrepancy in reported visibility and storm strength highlights the volatility of space weather forecasting. While a G1 storm is minor, a G2 storm represents a moderate disturbance that significantly increases the likelihood of the aurora being seen at lower latitudes. The potential for multiple CMEs to hit Earth in succession suggests a prolonged period of solar activity that could keep the lights visible for several nights.