2 sentences

1. 预报说明天多云转晴。

   yù​bào shuō míng​tiān duō​yún zhuǎn qíng.

   The forecast says it will be cloudy tomorrow, then turning clear.

   Source: Dong Chinese Dictionary

2. 阴转多云。

   yīn zhuǎn duō​yún.

   Overcast turning to cloudy.

   Source: Dong Chinese Dictionary