An M6.8 solar flare has erupted, according to EarthSky reporting on solar activity. More significant for near-term risk: two CMEs launched on June 19 and June 20 remain in the forecast pipeline and are expected to arrive in Earth's vicinity over the next 24 hours.
The June 19 CME may deliver a glancing blow around 8:00 UTC on June 23, according to EarthSky's summary. The June 20 CME could arrive around 10:00 UTC on June 24. Current Kp index estimates range from 3 to 5, which suggests at most G1 (minor) geomagnetic storm potential.
For context: G1 storms are the lowest category on NOAA's geomagnetic storm scale. At this level, power grid fluctuations may occur in high-latitude systems, and weak power grid irregularities are possible. Satellite operations and HF radio propagation may be affected. GPS and communications systems at far northern latitudes face greater risk than continental US infrastructure.
The flare itself is notable—M-class events are moderate-level solar eruptions. But the real operational variable is whether the CME trajectory actually intersects Earth's magnetosphere. EarthSky's language—"glancing blow"—suggests offset geometry, which would reduce geomagnetic coupling and lower storm severity. That aligns with the modest Kp forecast.
What matters now is observation. NOAA's Space Weather Prediction Center monitors real-time solar wind data and refines forecasts as CMEs approach. If either event produces stronger-than-forecast magnetic field coupling, Kp could climb into G2 range (moderate storm), which carries wider operational risk to grid operators and long-haul communication systems. If deflection holds, storm impacts remain contained to polar regions and specialized infrastructure.
For preparedness professionals: this is a low-probability, monitored scenario. Monitor NOAA Space Weather forecasts through June 24. If Kp rises above 6 in real-time updates, that's a signal to brief stakeholders on contingency status. Current trajectory does not warrant emergency posture, but it's a live reminder that solar activity windows persist and forecasting remains probabilistic, not deterministic.
