The National Oceanic and Atmospheric Administration (NOAA) has significantly revised its forecast for an upcoming northern lights display, warning of strong to severe geomagnetic storms on Thursday, June 4, and continuing into Friday, June 5. These storms will result from multiple coronal mass ejections (CMEs), which are immense clouds of heated gas and magnetic fields expelled from the sun following solar flares, colliding with Earth’s magnetic field.
Skywatchers in the northern United States are encouraged to observe the northern sky after dark, weather permitting. A waning gibbous moon, illuminated at 82%, will rise in the east post-midnight and could obscure the view of the aurora by brightening the night sky.
Initial predictions indicated that the strongest aurora activity would primarily occur on Friday. However, NOAA’s current outlook raises the possibility of G2 (Moderate) and G3 (Strong) geomagnetic storms affecting North America on Thursday afternoon and evening, with isolated G4 (Severe) storms possible during the peak of the event overnight.
The advanced forecast comes after multiple Earth-directed CMEs were detected on June 3 and 4. When these CMEs travel closely in succession, they can interact and enhance one another, a phenomenon referred to as a “cannibal CME.” NOAA’s three-day prediction anticipates Kp values reaching 6.33 (G2) from 15:00 to 18:00 UTC and increasing to 6.67 (G3) between 18:00 and 21:00 UTC, aligning with evening hours in North America.
A G3 storm may illuminate the northern lights across broad regions, while isolated G4 conditions could extend visibility further south. Key states for potential viewing include Washington, Idaho, Montana, and others, with additional possibilities in states further south where skies are clear. Observers are advised to follow real-time space weather updates, as the auroral intensity will depend on the solar wind’s magnetic field orientation.
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