Nice day today, isn't it? 좋은 날씨군요.

What's the weather forecast for today? 오늘 일기 예보는 어떻습니까?

What's the temperature today? 오늘 온도가 어떻게 됩니까?

 Do you know the weather report for tomorrow? 내일 기상 예보를 아세요?

How will be the weather tomorrow? 내일 날씨가 어떨까요?

How long do you think this weather will last? 이런 날씨가 얼마나 계속되리라고 생각하십니까?

Do you think it will be clear? 맑을 거라고 생각하세요?

Do you think it will rain (snow)? 비(눈)가 올 거라고 생각하세요?

We'll have rain tomorrow 내일은 비가 올 겁니다.

Do you think tomorrow will be warm (could)? 내일 따뜻할(추울) 거라고 생각하세요?
 

It's a nice day today. 오늘 날씨가 좋군요.

It certainly is a nice day, isn't it? 정말 좋은 날씨죠?

It's warm today.오늘 날씨가 따뜻하군요.

It's going to be fine.날씨가 맑겠습니다.

It has stopped raining(snowing). 비(눈)가 멈췄습니다.

 
It's very bad weather today, isn't it? 날씨가 매우 안 좋지요?

It seems cloudy today. 오늘은 날이 흐릴 것 같군요.

It's likely to rain(snow). 비(눈)가 올 것 같아요.

It's cold (hot) today. 오늘은 춥군요(덥군요).

It's very hot(cold) today. 오늘은 매우 덥군요(춥군요).

It's very hot and humid today. 매우 덥고 습기찬 날입니다.

It's windy today. 오늘은 바람이 붑니다.

 
The weather is changeable these days. 요즈음 날씨가 변덕스럽군요.

The weather forecasts are not to be relied on. 일기 예보는 믿을 수가 없습니다.

(주) rely on: 의지하다 (=depend), 믿다(= trust, count, reckon)

You can't rely on the weather forecasts. 일기 예보는 믿을 수가 없습니다.