Geomagnetic Storms
Widespread voltage control problems and protective system problems can occur, some grid systems may experience complete collapse or blackouts. Transformers may experience damage.
May experience extensive surface charging, problems with orientation, uplink/downlink and tracking satellites.
Pipeline currents can reach hundreds of amps, HF (high frequency) radio propagation may be impossible in many areas for one to two days, satellite navigation may be degraded for days, low-frequency radio navigation can be out for hours, and aurora has been seen as low as Florida and southern Texas (typically 40° geomagnetic lat.).

Solar Radiation Storms
Passengers and crew in high-flying aircraft at high latitudes may be exposed to elevated radiation risk.
Infrequent single-event upsets possible.
Small effects on HF propagation through the polar regions and navigation at polar cap locations possibly affected.

Radio Blackouts
Limited blackout of HF radio communication on sunlit side, loss of radio contact for tens of minutes.
Degradation of low-frequency navigation signals for tens of minutes.

Geomagnetic Storms forecast
Possible widespread voltage control problems and some protective systems will mistakenly trip out key assets from the grid.
May experience surface charging and tracking problems, corrections may be needed for orientation problems.
Induced pipeline currents affect preventive measures, HF radio propagation sporadic, satellite navigation degraded for hours, low-frequency radio navigation disrupted, and aurora has been seen as low as Alabama and northern California (typically 45° geomagnetic lat.).

Solar Radiation Storms forecast
Minor impacts on HF radio in the polar regions.

Radio Blackouts forecast
Wide area blackout of HF radio communication, loss of radio contact for about an hour on sunlit side of Earth.
Low-frequency navigation signals degraded for about an hour.