Lightning is nothing to worry about. Aircraft designers know planes spend their lives in clouds and design them to handle it. Those little rods that stick out at the wingtips are lightning discharge conductors. Probably hundreds of FT'ers have been struck (including me. Most impressed, the lights inside never even flickered). The engineers check the aircraft afterwards to see if there are any burn marks.

The ground issue is really one of not allowing refuelling while lightning is about. After a short while that obviously messes up the whole arrival and departure sequence.