NOAA issues geomagnetic storm watch as CMEs head toward Earth — northern lights possible Aug. 27-28

Aurora chasers are on alert after NOAA's Space Weather Prediction Center (SWPC) issued a moderate (G2) geomagnetic storm watch for Friday (Aug.

28), as coronal mass ejections (CMEs) launched from the sun yesterday (Aug.

25) head toward Earth.

The CME arrival follows a powerful M6.9 solar flare from restless sunspot region 4513 on Aug.

25.

NOAA's SWPC has also issued a minor (G1) geomagnetic storm watch for Thursday (Aug.

27), as a stream of fast solar wind from a coronal hole is expected to buffet Earth ahead of the incoming CMEs The M6.98 solar flare erupted from the active sunspot region 4513 and peaked at 6 a.m.

EDT (1000 GMT), according to SpaceWeatherLive .

4513 has been particularly active over the previous 24 hours, firing off a barrage of solar flares including five powerful M-class eruptions.

Solar flares are ranked by strength into five classes — A, B, C, M and X — with each class 10 times more powerful than the one before it.

M-class flares are the second-strongest category, sitting just below the most powerful X-class eruptions.

The eruption also triggered a moderate (R2) radio blackout across the sunlit side of Earth, affecting high-frequency radio communications over parts of Africa, Europe and the Arctic.

High-frequency radio blackouts from the M-class solar flare on Aug.

25. (Image credit: NOAA Space Weather Prediction Center) CME incoming and possible northern lights? The M6.9 flare wasn't the only eruption to launch material into space on Aug.