Opal/Thunder Egg

[uRBAN_Spaceman]

Is there something specific I need to do to get Thunder Eggs to spawn during storms? I've had 2 total in my game so far and I am entering my third year. I've heard plenty of lightning sounds like when it spawns but can never find an egg. Also Havent seen an Opal node in my overworld in 3 seasons now. What is going on?

[100% Recycled Awesome]

No, it's random that lightning will hit and leave a thunder egg and lighting strikes are very rare.

It's also a reason why it's nearly impossible to get the achievement related to lightning.

[sirguylittle]

The only thing you can really do is stay in one place during a thunderstorm. Find something to do outdoors like working on processing stuff so that you stay in one area and there is a slightly higher chance of a strike nearby.
To help with opals get Franklyn to make you lots of quarries.

[camm91]

Opals stick out like dogs balls when flying around in a helicopter at nighttime. They're rare but i see em semi regularly.