The NOAA Space Weather Prediction Center is forewarning of the opportunity to view the aurora borealis (aka northern lights) tonight.
The geomagnetic storm began as forecasted and quickly ramped up to severe (G4) levels. SWPC issued the G4 Alert at 1858 UT (2:58 pm EDT), after the storm slammed into Earth at 1839 UT (2:39 pm EDT). This is the same intensity level reached in March, 2015 during the St. Patrick’s Day storm. This is the very early stages of an event that will play out over many hours, with SWPC forecasting continuing storm level intensities into tomorrow.
Typically clouds get in the way but we are enjoying mostly clear skies. But the sun sets late (summer solstice) so you will have to wait a bit longer for the desirable darkness.
Puget Sound northern lights watchers get excited when the K Index reaches 7 but this event is already hitting a solid 8. So they are getting really excited.
You can monitor the approach of the Aurora and anticipate when it might be visible using the real-time graphics provided on NOAA’s 30-minute Aurora Forecast page.
From NOAA @7:30pm PDT – The geomagnetic storm that peaked at G4 (Severe) levels at mid-day on June 22 continues to hammer Earth, producing G3 (Strong) storm levels almost 8 hours after the coronal mass ejection first struck Earth’s magnetic field. G3 conditions were most recently reached June 23 at 0218 UT (June 22 10:18 pm EDT). We are now into the main phase of the storm and the solar wind conditions remain highly favorable for continued Strong Geomagnetic storming, with both fast solar wind and strong magnetic fields. Aurora watchers in North America, especially northern tier states of the US, should stay alert