Plain-language answer: Auroral propagation uses scattering or refraction from disturbed ionization near the auroral zones, often producing rough, distorted VHF or HF signals.
Why operators care
Geomagnetic activity can create unusual high-latitude paths while degrading ordinary F-layer HF propagation. Polarization and antenna direction may differ from the great-circle bearing.
What to compare on air
Track geomagnetic conditions, listen for characteristic distortion, and sweep headings toward the auroral oval.
The common mistake
Calling every fluttery polar signal an equipment fault.
Forecast boundary
Space-weather indices and propagation models describe probabilities and regional conditions. A usable contact still depends on the exact path, time, frequency, antenna pattern, noise, power, and current observations.
