The weather is great

"It has been raining" describes the weather conditions, which means "it rains a lot during the Qingming Festival, and it rains very finely".

"Sorrow is greater than death in the heart" describes the mood, which means "sorrow is greater than death in the heart".

"Brave and thunderous" describes the sound, which means "the heroic thunder resounds through the sky and spreads all over the vast world".

"The sound of birds singing and stirring" describes the sound, which means "birds with beautiful tunes are singing and their voices are stirring".

The meaning of the whole sentence is: during the Qingming Festival, the drizzle is falling, the mood is overcast, and the heroic thunder resounds through the sky and spreads throughout the vast world. Birds with beautiful tunes are singing and their voices are stirring.