Mainly attributing to the rain associated with broad troughs of low pressure, the active southerly airstream and tropical cyclones Maysak and Noul, the weather of Hong Kong was much gloomier and wetter than usual in July 2026. The total sunshine duration in the month was 122.2 hours, about 38 percent below the normal of 197.3 hours and the lowest on record for July. The mean amount of cloud in the month was 81 percent, 9 percentage points above the normal of 72 percent and one of the second highest on record for July. The total rainfall recorded at the Hong Kong Observatory Headquarters in the month was 790.3 millimetres, more than double the July normal of 385.8 millimetres and the second highest on record for July. The accumulated rainfall in the first seven months of the year was 1977.6 millimetres, about 35 percent above the normal of 1468.2 millimetres and the ninth highest on record for the same period. The monthly mean temperature for July 2026 was 28.7 degrees, close to the normal of 28.9 degrees.

Dominated by the subtropical ridge, apart from a few showers, local weather was mainly fine and very hot on the first day of the month. Meanwhile, Maysak formed as a tropical depression over the central part of the South China Sea in the morning and then tracked towards Hainan Island. The Observatory issued the Standby Signal No. 1 on the morning of 2 July, the first tropical cyclone warning signal of the year. Maysak skirted past Hainan the next day and intensified into a severe tropical storm over Beibu Wan on 4 July. Maysak moved into inland Guangxi on 5 July and weakened gradually. While local weather was hot with sunny periods on 2 July, there were also a few squally showers and thunderstorms, with more showers at night. Around 10 millimetres of rainfall were recorded over parts of the territory. Under the combined effect of Maysak and the ridge of high pressure over southeastern China, local winds were occasionally strong offshore and up to gale force on parts of high ground on 3 – 4 July. The outer rainbands of Maysak also brought occasional squally showers and severe squally thunderstorms on these two days. Violent gusts of about 100 and 90 kilometres per hour associated with severe squally thunderstorms were once recorded at Green Island and Star Ferry respectively. More than 40 millimetres of rainfall were recorded over many places, and rainfall even exceeded 80 millimetres over parts of Lantau Island on these two days.

An active southerly airstream brought showers and thunderstorms to Guangdong on 5 July. Locally, it was mainly cloudy with a few showers. Showers were heavier in some areas with squally thunderstorms at first. More than 10 millimetres of rainfall were recorded over many places. It became very hot with sunny periods during the day. Under the persistent influence of the active southerly airstream and the subsequent upper-air disturbances, local weather was cloudy with occasional heavy showers and squally thunderstorms on 6 – 8 July. Heavy showers brought more than 50 millimetres of rainfall to many places on 6 July, with amounts around 100 millimetres over localised areas of the New Territories. The heavy downpours on 7 July brought more than 70 millimetres of rainfall to the most of the territory, with over 140 millimetres at localised area around the Shek Kong and Ta Kwu Ling regions. Heavy showers subsequently subsided slightly on 8 July, with most places recording less than 50 millimetres of rainfall. With the moderation of the southerly airstream and departure of the upper-air disturbances, apart from a few showers and thunderstorms, there were sunny intervals during the day on 9 July. Meanwhile, tropical cyclone Bavi moved northwestward across the seas east of Taiwan. Under the influence of its outer subsiding air, local weather turned generally fine and very hot on 10 – 12 July. With plenty of sunshine, the temperature at the Observatory soared to a maximum of 34.5 degrees on the afternoon of 12 July, the highest of the month.

A broad trough of low pressure brought unsettled weather to the northern and central parts of the South China Sea on 13 July. Within the broad trough, an area of low pressure developed and edged closer to the coast of Guangdong. It made landfall over Zhuhai the next afternoon, then moved inland and dissipated. Locally, it was very hot with sunny periods and isolated showers on 13 July. An active southwesterly airstream started to bring unsettled weather to the coast of Guangdong on 14 July with the local weather turning mainly cloudy with occasional showers. More than 10 millimetres of rainfall were recorded over many places, and rainfall even exceeded 50 millimetres over Sai Kung and Sha Tin. The active southwesterly airstream continued to bring showers and thunderstorms to the coast of Guangdong and the northern part of the South China Sea on 15 July. Locally, showers were heavy at times with more than 50 millimetres of rainfall generally recorded over the territory, and rainfall even exceeding 70 millimetres over parts of the New Territories and Hong Kong Island. Under the influence of a broad trough of low pressure, the weather of Hong Kong remained unsettled with outbreaks of heavy showers and squally thunderstorms on 16 – 21 July, apart from slightly brighter sky on 19 July. More than 200 millimetres of rainfall were recorded over many places, and rainfall even exceeded 300 millimetres over parts of Lantau Island, Tsuen Wan and Kwai Tsing Districts on these six days.

With the broad trough of low pressure weakening and the subtropical ridge covering the coast of Guangdong, weather turned mainly fine and very hot on 22 – 24 July. Besides, Noul formed as a tropical depression over the western North Pacific to the east of the Philippines in the small hours of 23 July and then intensified gradually. It moved across the Luzon Strait and entered the northeastern part of the South China Sea in the following two days. It intensified into a severe typhoon before making landfall over Huizhou, Guangdong in the small hours of 26 July. It then moved inland and weakened rapidly. Locally, under the continual influence of the subtropical ridge, it was very hot with sunny periods at first on 25 July. The temperatures at the Observatory rose to the month’s highest of 34.5 degrees again in the afternoon. But as the Noul’s outer rainbands edged towards Guangdong coast, there were also occasional squally showers and severe squally thunderstorms that afternoon, with multiple districts affected by violent gusts. As Noul approached the territory, local winds strengthened significantly at night. The strike of Noul necessitated the issuance of the first Gale or Storm Signal No. 8 in the year that night and the Increasing Gale or Storm Signal No. 9 in the small hours of 26 July. Noul skirted about 80 kilometres to the northeast of the Hong Kong Observatory in the morning. Gales prevailed over many places, including Victoria Harbour, in the morning with occasional storm force winds offshore and on high ground. There were also heavy squally showers and thunderstorms. More than 70 millimetres of rainfall were generally recorded over the territory on 26 July, and rainfall even exceeded 140 millimetres over the eastern part of the New Territories. According to preliminary reports, at least 21 people were injured during the passage of Noul. There were at least 331 reports of fallen trees and 8 reports of flooding.

Under the influence of a broad trough of low pressure, local weather was cloudy with occasional heavy showers and squally thunderstorms on the last five days of the month. More than 150 millimetres of rainfall were recorded over most parts of the territory, and rainfall even exceeded 250 millimetres over parts of Hong Kong Island on these five days. In the midst of the downpour, the temperature at the Observatory dropped to a minimum of 23.9 degrees on the last day of the month, the lowest of the month.

Five tropical cyclones occurred over the South China Sea and the western North Pacific in July 2026.