Too much information is context sensitive (at least with my daughter). On a good day with no threats of bad weather we can discuss thunderstorms and tornados and how to prepare and react with no problems. A little bit of rain and lightning and all she wants / needs is comfort with very little rationale discussion. So I educate when all is calm and provide support/diversions when things aren't so calm.

Everyone is different but I'm sure you can judge how much is too much for your son as circumstances change.

-Eric