Solar activity, geomagnetic conditions, and operational impact assessment
Kp Index
2.7
low stormRisk Score
18
/100 analytical
Solar Flares (7d)
1
C-class only
Geomagnetic Storm
None
Ionospheric disturbances can degrade GPS accuracy by 2–10m at high Kp. HF radio blackouts possible during X-flares.
Elevated atmospheric heating expands thermosphere, increasing drag on LEO satellites. Orbit decay accelerated at Kp ≥ 5.
HF radio blackouts affect transpolar flight communications. Airlines may reroute away from polar tracks during major events.
Geomagnetically induced currents (GIC) can stress high-voltage transformers. G4–G5 storms historically caused grid failures.
Current radiation storm level: S1 - Minor. Solar energetic particles impact spacecraft electronics and crewed missions.
The flare was produce by the unnumbered Active Region just behind the limb. This is likely the Active Region that would be numbered AR 14535.
Coronal Mass Ejections
2026-09-18 03:24 UTC
CME visible to the NE in SOHO LASCO C2/C3. The CME is also faintly visible to the NE in GOES CCOR-1 following a data gap due to Earthshine from 2026-09-18T03:45Z to 2026-09-18T06:10Z. The CME is not visible in STEREO A COR2 imagery. The source is beyond the NE limb and is seen as moving field lines starting at 2026-09-18T02:35Z in GOES SUVI 284 and SDO AIA 171/193 imagery.
2026-09-19 16:38 UTC
Faint, narrow CME seen to the SW in SOHO LASCO C2 and STEREO A COR2 and very faintly seen in a couple of frames of GOES CCOR-1 coronagraph imagery. The CME is not seen in SOHO LASCO C3. Its source is likely seen in STEREO A EUV 304 imagery as a large ejecta off the W limb after 2026-09-19T15Z and not seen in any other EUV imagery. The ejecta is not clearly visible, and it's exact location/longitude is unclear, but it seems to be close to the limb (which would be ~159 deg).
2026-09-19 18:48 UTC
Faint, minor CME with an unclear front seen to the E-NE in SOHO LASCO C2. Not seen in other coronagraphs. Its source is the long duration C3.3 class flare from unnumbered AR rotating onto disk (N14E90) peaking at 2026-09-19T18:17Z. There is also an associated opening of field lines on/behind the E limb seen in SDO AIA 193 and a minor prominence/ejecta seen in SDO AIA 304/171 starting after 2026-09-19T18:10Z. The initial front is followed by a series of outflows.
2026-09-19 22:12 UTC
CME observed to the NW in SOHO LASCO C2/C3, GOES CCOR-1, and STEREO A COR2. The source is a far-sided filament eruption over the NW limb, observed best in GOES 284/304 starting around 2026-09-19T21:22Z. When STEREO A EUVI 304/195 return from a data gap at 2026-09-20T00:15Z and 2026-09-20T00:25 respectively, dimming and post eruptive brightening can be seen in the NW disk, likely left behind by this filament eruption.
2026-09-19 22:24 UTC
CME observed brightly to the SW in STEREO A COR2, and very faintly to the SE in SOHO LASCO C2/C3 and GOES CCOR-1. No source is seen in on-disk EUV imagery for this event, and is likely far-sided.
No active geomagnetic storm detected.
NOAA Alert Levels