Question about かな and だろう

Question

Among these phrases which is the correct one?

今日は雨が降るかな

or

今日は雨が降るだろう／でしょう

Answer 1

Both are grammatically correct. They can mean...

今日は雨が降るかな
"I wonder if it will rain today." / "Will it rain today?"

今日は雨が降るだろう／でしょう
"It will (probably) rain today." / "I think it will (probably) rain today." / "It will rain today, won't it?"

... depending on intonation and context.