What type of figurative language is this" another sunny day in Seattle," she said, snarling at the overcast sky.?

Taking into consideration that the speaker is stating one thing while meaning the complete opposite, we can conclude that the sentence "A nother sunny day in Seattle" is an example of verbal irony.

The very definition of verbal irony is when someone says/writes something and means something different, or when they do so in a way that will transmit the completely opposite meaning.