G2 isn't too bad.
G scale 1-3 is minor. G4 and 5 would make me nervous.
-NOAA def.
G2 (Moderate) Geomagnetic Storm Impacts
Power systems: High-latitude power systems may experience voltage alarms, long-duration storms may cause transformer damage.
Spacecraft operations: Corrective actions to orientation may be required by ground control; possible changes in drag affect orbit predictions.
Other systems: HF radio propagation can fade at higher latitudes, and aurora has been seen as low as New York and Idaho (typically 55° geomagnetic lat.).
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events in the G scale mostly involve power transmission, radio and satellites. the link below is the low level events.
http://www.swpc.noaa.gov/sites/default/files/images/NOAAscales.pdf-
i work in the radio industry. here is the noaa page i find most useful. the earlier link Nemo is from the email alerts.
this one and the PDF might help more.
http://www.swpc.noaa.gov/communities/emergency-managementhere is an overview
https://en.wikipedia.org/wiki/Solar_flareOk, one last note. the above scales are for typical events. if you hear a forecast for higher levels, just remember two things. the scales are log10 if the earth were to be hit it wouldn't be good. i keep a weather eye out for "M" and "X" class.