Present TENSE: "What is the WEATHER like today?"
-You might ask that to someone who:
1) Has had the chance to go outside before you have. or,
2) Someone who is in a different location than where you are.
For example, since you are in Ukraine, I would ask you "what is the weather like today?" because I'm not there, so I don't know.
Future Tense: You have a few choices
1) What is tomorrow's weather going to be like?
2) Tomorrow's weather will be.... (This is a statement, not a question)
3) What's the forecast for _____? (tomorrow, the weekend, next week, etc.)