Attributing to the warmer-than-normal sea surface temperature over the northern part of the South China Sea and the southwesterly flow in the lower atmosphere over the coast of southern China, as well as the high temperature weather brought by the outer subsiding air of Tropical Cyclone Dolphin, August 2026 was much hotter than usual in Hong Kong. The monthly mean temperature of 29.5 degrees, mean minimum temperature of 27.6 and mean maximum temperature of 32.1 degrees were 0.8 degrees, 0.9 degrees and 0.8 degrees above their respective normals and were respectively one of the third, the fourth and one of the eighth highest on record for August. With a total of nine consecutive very hot days from 5 to 13 August, August 2026 was the month with one of the longest consecutive very hot days on record for August. Among these, there were three consecutive extremely hot days from 9 to 11 August, being the highest number of extremely hot days and also the longest consecutive extremely hot days for August. Mainly owing to the high temperature weather in August, the summer of this year from June to August was slightly hotter than usual. The mean temperature of 28.9 degrees was 0.2 degrees above the normal for the same period. The monthly rainfall was 380.0 millimetres, about 16 percent below the normal figure of 453.2 millimetres. The accumulated rainfall recorded in the first eight months of the year was 2357.6 millimetres, about 23 percent above the normal figure of 1921.5 millimetres for the same period.

The broad trough of low pressure that affected the coast of Guangdong since late July continued its dominance into the early part of August. Locally, it was mainly cloudy with occasional heavy showers on the first three days of the month. There were also thunderstorms on 1 – 2 August. Heavy showers brought more than 100 millimetres of rainfall to most parts of the territory, and rainfall even exceeded 200 millimetres over the eastern part of Hong Kong Island and New Territories East on these three days. Under the showers, the temperature at the Observatory dropped to a minimum of 25.0 degrees on 3 August, the lowest of the month. The Observatory recorded maximum temperatures below 30.0 degrees for nine consecutive days from 26 July to 3 August, a rare occurrence during the usual hot season in July and August, with the last nine-day spell dating back to August 1937. As the broad trough weakened on 4 August, local weather improved with sunny periods and a few showers. Winds were weak in the following two days. Local weather was very hot with more sunshine on the afternoon of 5 August and the next day.

The outer subsiding air of Tropical Cyclone Dolphin and the subsequent southwesterly airstream brought generally fine and very hot weather to the territory in the next seven days. In particular, it was extremely hot on 9 – 11 August. The temperature at the Observatory on the afternoon of 9 August soared to the all-time record-breaking high of 36.9 degrees. Meanwhile, the temperature at Sheung Shui reached 39.8 degrees, the highest ever recorded in Hong Kong since the establishment of automatic weather stations in the 1980s. Furthermore, the minimum temperature recorded at the Observatory on the morning of 12 August was 30.2 degrees, setting another record as the highest daily minimum temperature on record.

Under the influence of upper-air disturbances and a southwesterly airstream, local weather was mainly cloudy with occasional showers and squally thunderstorms on 14 August and on the morning of 15 August. Showers were heavy at times. More than 40 millimetres of rainfall were recorded over many places, and rainfall even exceeded 100 millimetres over the Southern District on these two days. With the departure of the upper-air disturbances and the moderation of the southwesterly airstream, apart from isolated showers in the morning, local weather turned mainly fine and very hot on 16 August. Winds were weak over Guangdong the next day. Locally, it was mainly cloudy with a few showers and thunderstorms, with showers being heavier in some areas around noon due to heat-triggered thunderstorms, and more than 30 millimetres of rainfall recorded.

A broad trough of low pressure brought showers and thunderstorms to the coast of Guangdong and the northern part of the South China Sea on 18 – 24 August. Locally, under the combined effect of an area of low pressure within the broad trough over the northern part of the South China Sea and the ridge of high pressure over southeastern China, local easterly winds were stronger on the night of 18 August and the next day. Under the influence of the broad trough, it was mainly cloudy with a few showers and sunny intervals during 18 – 24 August. Showers were heavier on 20 August with around 10 millimetres of rainfall recorded over many places and rainfall even exceeding 40 millimetres over Hong Kong Island and parts of Kowloon. There were also isolated thunderstorms on 21 – 22 August. Besides, the area of low pressure within the broad trough intensified gradually into a tropical cyclone over Beibu Wan on 20 August and was later named as Narra. Narra lingered over the vicinity of Beibu Wan in the next few days. It made landfall near Wuchuan after moving across Leizhou Peninsula and weakened into a low pressure area on 26 August.

Under the influence of an active southerly airstream and a subsequent trough of low pressure, local weather was cloudy with occasional showers and squally thunderstorms on 25 – 27 August. More than 80 millimetres of rainfall were recorded over many places, and rainfall even exceeded 200 millimetres over the eastern part of Hong Kong on these three days. The heavy downpour also necessitated the issuance of the Red Rainstorm Warning Signal on the morning of 27 August. Unfortunately, a man was found unconscious on a sampan near the Tseung Kwan O Cross Bay Link and later died in hospital, with initial reports suggesting he may have been struck by lightning. Although it was hot with sunny periods due to the moderation of the active southerly airstream, a broad trough of low pressure also brought a few showers and thunderstorms on 28 – 29 August. Showers were heavy in some areas during the small hours on 28 August with about 70 millimetres of rainfall recorded over Tai Po and Lau Fau Shan. With the dominance of the broad trough over the coastal regions, showers increased gradually on the last two days of the month. Showers were heavy at times with a few squally thunderstorms on 31 August. About 30 millimetres of rainfall were recorded over many places, and rainfall even exceeded 50 millimetres over Kowloon and parts of the New Territories West. Besides, Tropical Cyclone Saudel made landfall over Zhejiang on 28 August and, over the following day or two, moved across eastern China and central China before weakening into an area of low pressure over southern China. Its remnant tracked southwards across the Leizhou Peninsula and Hainan Island on 31 August, and in the evening of that day emerged over the waters just off the southeast coast of Hainan Island, where it re-intensified into a tropical depression. The Observatory subsequently issued the Standby Signal No. 1.

13 tropical cyclones occurred over the South China Sea and the western North Pacific in August 2026.

Details of issuance and cancellation of various warnings/signals in the month are summarised in Tables 1.1 to 1.5. Monthly meteorological figures and departures from normal for August are tabulated in Table 2.

Please refer to the following link for the latest monthly forecast: Monthly Forecast
 

Warnings and Signals issued in August 2026

Table 1.1   Tropical Cyclone Warning Signals

Name of Tropical Cyclone	Signal Number	Beginning Time		Ending Time
		Day/Month	HKT	Day/Month	HKT
SAUDEL	1	31 / 8	1810	4 / 9	0010

Table 1.2   Strong Monsoon Signal

Beginning Time		Ending Time
Day/Month	HKT	Day/Month	HKT
18 / 8	2210	20 / 8	0710

Table 1.3   Rainstorm Warning Signals

Colour	Beginning Time		Ending Time
	Day/Month	HKT	Day/Month	HKT
Amber	2 / 8	0610	2 / 8	1300
Amber	3 / 8	0640	3 / 8	0845
Amber	14 / 8	0840	14 / 8	1140
Amber	15 / 8	0235	15 / 8	0505
Amber	26 / 8	1845	26 / 8	2040
Amber	27 / 8	0000	27 / 8	0200
Amber	27 / 8	0430	27 / 8	0505
Red	27 / 8	0505	27 / 8	0920
Amber	27 / 8	0920	27 / 8	1015
Amber	31 / 8	1225	31 / 8	1405

Table 1.4   Thunderstorm Warning

Beginning Time		Ending Time
Day/Month	HKT	Day/Month	HKT
31 / 7	2200	1 / 8	0415
1 / 8	0645	1 / 8	0900
1 / 8	1020	1 / 8	1535
1 / 8	1730	1 / 8	2000
2 / 8	0505	2 / 8	1500
2 / 8	1900	3 / 8	1000
4 / 8	1250	4 / 8	1600
13 / 8	2340	14 / 8	0300
14 / 8	0445	14 / 8	1355
14 / 8	2226	15 / 8	1015
17 / 8	1035	17 / 8	1700
18 / 8	1900	18 / 8	2230
20 / 8	0840	20 / 8	1145
20 / 8	1905	20 / 8	2030
21 / 8	0030	21 / 8	0545
22 / 8	1752	22 / 8	2230
23 / 8	1400	23 / 8	1600
24 / 8	1118	24 / 8	1330
24 / 8	2015	24 / 8	2130
25 / 8	0233	25 / 8	0830
25 / 8	1020	25 / 8	1330
25 / 8	1535	25 / 8	2030
26 / 8	0520	27 / 8	1445
28 / 8	0035	28 / 8	0555
29 / 8	0211	29 / 8	0400
29 / 8	1540	29 / 8	1800
30 / 8	0940	30 / 8	1500
31 / 8	1130	31 / 8	1425
31 / 8	1707	31 / 8	2210

Table 1.5   Very Hot Weather Warning

Beginning Time		Ending Time
Day/Month	HKT	Day/Month	HKT
5 / 8	0645	13 / 8	1920
16 / 8	0645	17 / 8	1620
23 / 8	1310	23 / 8	1620
24 / 8	1045	24 / 8	1845
28 / 8	1340	28 / 8	1820
29 / 8	0840	29 / 8	1800

Table 2   Figures and Departures from Normal - August 2026

Meteorological Element	Figure of the Month	Departure from Normal*
Mean Daily Maximum Air Temperature	32.1 degrees C	0.8 degrees above normal
Mean Air Temperature	29.5 degrees C	0.8 degrees above normal
Mean Daily Minimum Air Temperature	27.6 degrees C	0.9 degrees above normal
Mean Dew Point Temperature	25.4 degrees C	0.3 degrees above normal
Mean Relative Humidity	79 %	2 % below normal
Mean Cloud Amount	78 %	8 % above normal
Total Rainfall	380.0 mm	73.2 mm below normal
Number of hours of Reduced VisibilityΔ	0 hours	35.3 hours below normal§
Total Bright Sunshine Duration	168.9 hours	13.2 hours below normal
Mean Daily Global Solar Radiation	16.42 Megajoule / square metre	0.69 Megajoule above normal
Total Evaporation	107.0 mm	22.7 mm below normal

Remarks :	All measurements were made at the Hong Kong Observatory except sunshine, solar radiation and evaporation which were recorded at King's Park Meteorological Station and visibility which was observed at the Hong Kong International Airport.
Δ	The visibility readings at the Hong Kong International Airport are based on hourly observations by professional meteorological observers in 2004 and before, and average readings over the 10-minute period before the clock hour of the visibility meter near the middle of the south runway from 2005 onwards. The change of the data source in 2005 is an improvement of the visibility assessment using instrumented observations following the international trend. Before 10 October 2007, the number of hours of reduced visibility at the Hong Kong International Airport in 2005 and thereafter displayed in this web page was based on hourly visibility observations by professional meteorological observers. Since 10 October 2007, the data have been revised using the average visibility readings over the 10-minute period before the clock hour, as recorded by the visibility meter near the middle of the south runway.
*   Departure from 1991 - 2020 climatological normal, except for number of hours of reduced visibility
§   Departure from mean value between 1997 and 2025

Remarks :

Extremely high: above 95th percentile Above normal: between 75th and 95th percentile Normal: between 25th and 75th percentile Below normal: between 5th and 25th percentile Extremely low: below 5th percentile Percentile and 5-day running average values are computed based on the data from 1991 to 2020

Extract of Meteorological Observations in Hong Kong for August 2026