In the weather widget there is a screen with a 12 hour trend, how do I read that screen? Yellow line is between 9 and 10 value? And from 4 till 8 there is rain expected?

In the weather widget there is a screen with a 12 hour trend, how do I read that screen? Yellow line is between 9 and 10 value? And from 4 till 8 there is rain expected?
