The Weather of March 2022
The weather in Hong Kong was mainly fine on the first day of the month. Affected by a relatively humid easterly airstream, the weather gradually turned cloudier with mist in some areas on 2 - 3 March. With the clouds thinning out, apart from mist patches in the morning and at night, it was generally fine during the day on 4 March. Under light wind conditions, the weather of Hong Kong remained fine but became foggy on 5 March. The visibility in some areas once fell to about 100 metres. With winds strengthening from the east, local weather turned mainly cloudy that night, but became dry with sunny intervals during the day on 6 March.
A cold front moved across the coast of Guangdong on the morning of 7 March and brought cooler weather and some rain patches to Hong Kong. Under the influence of the dry northerly airstream, local weather became generally fine and dry in the afternoon. The weather of Hong Kong remained fine and dry in the next five days. In particular, it was rather cool on the morning of 8 March with the temperature at the Observatory dropping to a minimum of 15.0 degrees, the lowest of the month. It was also very dry in the afternoons of 8 - 9 March with the relative humidity over parts of the territory falling below 40 percent.
A mild maritime airstream replaced the northeast monsoon on 13 March and prevailed over the coast of Guangdong till 22 March. Locally, it was generally fine and rather warm on 13 – 15 March. It was also foggy on the morning of 15 March. Affected by cloud bands over southern China, the weather became mainly cloudy with some mist patches on 16 March. Apart from coastal fog and a few showers in the morning, there were sunny periods during the day on 17 March. It was foggy in Hong Kong on 18 – 22 March. The visibility in the harbour and at Waglan Island once fell to 100 metres or below during the night of 18 March and the next morning. There were also a few showers on 20 – 22 March and isolated thunderstorms in the New Territories on 20 March.
A cold front moved across the coast of Guangdong on the morning of 23 March and brought cooler weather and showers to Hong Kong on that day. Showers were more frequent in the morning. More than 50 millimetres of rainfall were recorded over many places of the territory on that day. Affected by a fresh to strong easterly airstream, the weather remained cloudy with cool mornings and a few rain patches on 24 – 25 March. With the easterly airstream gradually replaced by a southerly airstream later on 25 March, there were a few showers and coastal fog on 26 March. The visibility at Waglan Island once fell below 500 metres on that day.
Another cold front moved across the coast of Guangdong in the small hours of 27 March. Locally, under the influence of the associated northeast monsoon, it was cloudy and cooler with a few showers on that day. It was also foggy in the morning with visibility in the harbour once falling to around 1000 metres. Affected by a band of thundery showers, it was cloudy with showers and a few squally thunderstorms at first on 28 March. More than 30 millimetres of rainfall were recorded over many places and rainfall even exceeded 50 millimetres over the northeastern part of the New Territories. The weather remained cloudy with a few showers on 29 March. With the moderation of the northeast monsoon, local weather improved gradually with more sunshine and temperature rising on the last two days of the month. The temperature at the Observatory rose to a maximum of 29.3 degrees on the afternoon of 31 March, the highest of the month.
There was no tropical cyclone over the South China Sea and the western North Pacific in March 2022.
Sea fog near Sham Tseng on 5 March 2022 (Courtesy of SY CHEUNG)
Fog near Kwai Chung on 5 March 2022 (Courtesy of CHUNG MING LEE)
Sea fog near Wan Chai on 18 March 2022 (Courtesy of Nick Choy)
Sea fog near West Kowloon Cultural District on 18 March 2022 (Courtesy of Bin Cheung)
Details of issuance and cancellation of various warnings/signals in the month are summarized in Tables 1.1 to 1.3. Monthly meteorological figures and departures from normal for March are tabulated in Table 2.
Warnings and Signals issued in March 2022
|Beginning Time||Ending Time|
|6 / 3||0845||6 / 3||1145|
|25 / 3||0035||25 / 3||1145|
|Beginning Time||Ending Time|
|20 / 3||1125||20 / 3||1400|
|23 / 3||0217||23 / 3||0625|
|23 / 3||0810||23 / 3||1000|
|25 / 3||1355||25 / 3||1500|
|27 / 3||2315||28 / 3||0830|
|Colour||Beginning Time||Ending Time|
|Yellow||6 / 3||0600||6 / 3||1745|
|Red||8 / 3||0600||9 / 3||0600|
|Yellow||9 / 3||0600||9 / 3||1145|
|Red||9 / 3||1145||9 / 3||2300|
|Yellow||10 / 3||0600||11 / 3||1900|
|Yellow||12 / 3||0930||12 / 3||2145|
|Yellow||13 / 3||0750||13 / 3||1800|
|Meteorological Element||Figure of the Month||Departure from Normal*|
|Mean Daily Maximum Air Temperature||25.0 degrees C||3.1 degrees above normal|
|Mean Air Temperature||21.5 degrees C||2.0 degrees above normal|
|Mean Daily Minimum Air Temperature||19.2 degrees C||1.6 degrees above normal|
|Mean Dew Point Temperature||17.4 degrees C||1.3 degrees above normal|
|Mean Relative Humidity||79 %||3 % below normal|
|Mean Cloud Amount||64 %||13 % below normal|
|Total Rainfall||92.7 mm||17.4 mm above normal|
|Number of hours of Reduced VisibilityΔ||40 hours||57.0 hours below normal§|
|Total Bright Sunshine Duration||169.5 hours||69.5 hours above normal|
|Mean Daily Global Solar Radiation||15.08 Megajoule / square metre||4.37 Megajoule above normal|
|Total Evaporation||91.2 mm||18.0 mm above 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.
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.
|*||Departure from 1991 - 2020 climatological normal, except for number of hours of reduced visibility|
|§||Departure from mean value between 1997 and 2021|
|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