 Complete the following phrase:  In preparation for the tropical depression, the HKO issued a Signal No. 1 warning for Hong Kong at 13:40 UTC on July 18, which was later upgraded to a Signal No. 3 warning as Cempaka neared the Pearl River Delta. However, as it moved away from Hong Kong, the HKO downgraded it to a Signal No. 1 warning, which was later cancelled at 11:40 UTC. The CMA issued an orange alert for the southern provinces of China as Cempaka moved closer to Guangdong, China, though it was later downgraded to a blue alert as it entered the Chinese mainland. It was later lifted by the CMA, as the threat of Cempaka was minimal. As Cempaka made landfall in Guangdong, there were reports of heavy rainfall and rough waves in the region. Over 990 flights were cancelled in Guangzhou, Shenzhen and Zhuhai. The influence of Cempaka caused heavy rainfall in He Province, along with In-fa causing 