PLEASE DO NOT SKIP OR IGNORE ANY QUESTION.

I'm struggling to read the values of thunderstorm layer. There's no official clear documentation.

Would you please answer some questions regarding thunderstorms?

1) How do I know which value is strong/moderate or light from the thunderstorm layer?

2) Suppose, for 3 hour period (for example: 12am-3am) thunder data is 1.33 l/km2. Is the value only 12am to 3am (3 hour) period only? If not then how can I read the data for which time period? Because for every 3 hour period it shows different data.

3) How do you calculate this formula?

4) Where is the official documentation?

Please clarify everything. It's so confusing to understand how the formula works.

Thanks