June in Ha Long is the rainiest, the cloudiest, and the hottest month of the year. In June, the weather in Ha Long is typically hot. Average daily high temperature in June is about 30 degrees above zero. On average, Ha Long has 29 rainy and 1 sunny day in June. The rains are usually heavy. June as well as May, July, August, and September is considered the most uncomfortable time to visit Ha Long.