If you wouldn’t mind another question: How much time do they need for the weather to be clear so they can launch?
I believe for lightning, it has to be continuously clear for at least 15 minutes without a danger of going back into “RED”, although it might be 30 minutes.
The fact that they’re still going through the countdown is just academic. Practice, practice, practice.
Anvil clouds, cumulus clouds, field mills, and flight through rain are currently RED. It isn’t just lightning they’re dealing with. Since Challenger, they take NO chances.