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Monthly Climatological Normals for Hong Kong
Climatological Information Services > Climatological Normals and Extremes > 1971-2000 Normals for Hong Kong (Grouped by element)

Monthly Climatological Normals for Hong Kong

  1. Monthly mean numbers of days with tropical cyclone warning signals and Strong Monsoon Signal in Hong Kong between 1971-2000
  2. Monthly mean of rainfall in Hong Kong between 1971-2000
  3. Monthly mean numbers of days with lightning, thunderstorm and fog reported at the Observatory between 1971-2000
  4. Monthly means of daily maximum, mean and minimum temperature recorded at the Observatory between 1971-2000
  5. Monthly means of relative humidity, dew point temperature, wet-bulb temperature and vapour pressure recorded at the Observatory between 1971-2000
  6. Monthly means of cloud amount observed at the Observatory and sunshine duration and daily global solar radiation recorded at King's Park between 1971-2000
  7. Monthly means of prevailing wind direction and mean wind speed recorded at the Observatory and Waglan Island between 1971-2000
  8. Monthly mean of atmospheric pressure recorded at the Observatory between 1971-2000
  9. Monthly means of sea surface temperature recorded at North Point and Waglan Island, and evaporation and potential evapotranspiration recorded at King's Park between 1971-2000
  10. Monthly mean of soil temperature recorded at the Observatory between 1971-2000


 

Table 1.   Monthly mean numbers of days with tropical cyclone warning signals and
Strong Monsoon Signal in Hong Kong between 1971-2000
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Month
Number of Days with
Tropical Cyclone Warning Signal
Number of Days with
Strong Monsoon Signal
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No. 1 and/or
higher
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No. 3 and/or
higher
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No. 8 and/or
higher
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No. 9 and/or
No. 10
January - - - - 4.33
February - - - - 4.33
March - - - - 3.83
April 0.17 0.03 - - 3.00
May 0.43 0.27 0.07 - 1.60
June 2.23 1.23 0.20 0.03 1.17
July 4.43 2.57 0.57 0.07 0.50
August 3.93 1.67 0.60 0.13 0.17
September 4.53 2.23 0.40 0.07 1.77
October 3.17 2.03 0.20 0.07 5.30
November 0.50 0.17 0.07 - 4.83
December 0.07 0.07 - - 5.23
Year 19.46 10.27 2.11 0.37 36.07

Figure 1.1. Monthly mean number of days with tropical cyclone warning signals in Hong Kong between 1971-2000

Figure 1.1.   Monthly mean number of days with tropical cyclone warning signals in Hong Kong between 1971-2000

Figure 1.2. Monthly mean number of days with Strong Monsoon Signal in Hong Kong between 1971-2000

Figure 1.2.    Monthly mean number of days with Strong Monsoon Signal in Hong Kong between 1971-2000

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Table 2.   Monthly mean of rainfall in Hong Kong between
1971-2000
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Month
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Total
(mm)
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Duration
(hours)
Number of Days with
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0.1 mm
or more
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25 mm
or more
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50 mm
or more
January 24.9 43 5.60 0.20 0.00
February 52.3 76 9.47 0.53 0.07
March 71.4 91 10.47 0.67 0.30
April 188.5 87 11.67 2.57 1.23
May 329.5 101 15.47 3.77 2.00
June 388.1 95 18.77 4.17 2.13
July 374.4 80 17.77 4.67 2.40
August 444.6 87 17.43 5.40 2.40
September 287.5 68 14.80 3.47 1.60
October 151.9 50 8.10 1.57 1.00
November 35.1 36 5.67 0.37 0.10
December 34.5 36 4.27 0.30 0.13
Year 2382.7 850 139.49 27.69 13.36

Figure 2. Monthly mean of rainfall in Hong Kong between 1971-2000

Figure 2.   Monthly mean of rainfall in Hong Kong between 1971-2000

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Table 3.   Monthly mean numbers of days with lightning, thunderstorm and fog reported at the Observatory
between 1971-2000
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Month
Number of Days with
Lightning
Number of Days with
Thunderstorm
Number of Days with Fog
(Visibility < 1000 m)
January 0.13 0.10 0.23
February 1.00 0.97 1.23
March 1.77 1.63 2.30
April 4.77 4.20 1.13
May 6.67 5.27 0.17
June 7.70 5.60 -
July 8.47 5.90 -
August 11.00 8.10 -
September 6.93 4.30 -
October 1.13 0.80 -
November 0.23 0.23 -
December - - 0.03
Year 49.80 37.10 5.09

Figure 3. Monthly mean numbers of days with lightning, thunderstorm and fog reported at the Observatory between 1971-2000

Figure 3.    Monthly mean numbers of days with lightning, thunderstorm and fog reported at the Observatory between 1971-2000

 

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Table 4.   Monthly means of daily maximum, mean and minimum temperature recorded at the Observatory between 1971-2000
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Month
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Mean Daily
Maximum
(deg. C)
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Mean
(deg. C)
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Mean Daily
Minimum
(deg. C)
January 18.6 16.1 14.1
February 18.6 16.3 14.4
March 21.5 18.9 16.9
April 25.1 22.5 20.6
May 28.4 25.8 23.9
June 30.4 27.9 26.1
July 31.3 28.7 26.7
August 31.1 28.4 26.4
September 30.2 27.6 25.6
October 27.7 25.3 23.4
November 24.0 21.4 19.4
December 20.3 17.8 15.7
Year 25.6 23.1 21.1

Figure 4. Monthly means of daily maximum, mean and minimum temperature recorded at the Observatory between 1971-2000

Figure 4.   Monthly means of daily maximum, mean and minimum temperature recorded at the Observatory between 1971-2000

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Table 5.   Monthly means of relative humidity, dew point temperature, wet-bulb temperature and vapour pressure recorded at the Observatory
 between 1971-2000
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Month
Relative Humidity (%)  Dew Point 
Temperature
(deg. C)
Wet-bulb
Temperature
(deg. C)
Vapour
 Pressure 
(hPa)
    Mean     Mean at
0200 hours
Mean at
1400 hours
January 73 78 65 11.0 13.5 13.7
February 78 82 71 12.2 14.4 14.8
March 82 86 75 15.5 17.0 18.2
April 83 88 76 19.4 20.5 22.9
May 84 88 77 22.7 23.7 27.8
June 82 86 76 24.5 25.6 30.9
July 81 85 74 25.0 26.1 31.7
August 82 86 75 24.9 25.9 31.5
September 79 83 72 23.4 24.7 28.9
October 74 78 66 19.9 21.9 23.8
November 70 75 61 15.3 17.9 18.1
December 69 74 60 11.6 14.5 14.4
Year 78 82 71 18.8 20.5 23.1

Figure 5.1. Monthly mean of relative humidity recorded at the Observatory between 1971-2000

Figure 5.1.    Monthly mean of relative humidity recorded at the Observatory between 1971-2000

Figure 5.2. Monthly means of dew point temperature, web-bulb temperature and vapour pressure recorded at the Observatory between 1971-2000

Figure 5.2.    Monthly means of dew point temperature, web-bulb temperature and vapour pressure recorded at the Observatory between 1971-2000

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Table 6.   Monthly means of cloud amount observed at the Observatory and sunshine duration and daily global solar radiation recorded at King's Park between 1971-2000
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Month
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Cloud Amount
(%)
Bright Sunshine blank space
Daily Global
Solar Radiation
(MJ/m2)
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Duration
(hours)
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Percentage
of Possible
January 60 141.7 42 10.55
February 73 93.8 29 9.61
March 79 89.6 24 10.18
April 80 101.8 27 11.83
May 77 138.6 34 14.35
June 76 158.3 39 15.31
July 68 214.9 52 17.52
August 69 189.7 48 16.07
September 65 171.8 47 15.14
October 57 191.1 53 14.46
November 53 178.2 54 12.64
December 51 173.3 52 11.13
Year 67 1842.9 41 13.23

Monthly Cloud Amount Observed at the Observatory between 1971-2000   

Figure 6.1.    Monthly mean of cloud amount recorded at the Observatory between 1971-2000

Figure 6.2.    Monthly mean of sunshine duration recorded at King's Park between 1971-2000

Figure 6.2.    Monthly mean of sunshine duration recorded at King's Park between 1971-2000

Figure 6.3.    Monthly mean of daily global solar radiation recorded at King's Park between 1971-2000

Figure 6.3.    Monthly mean of daily global solar radiation recorded at King's Park between 1971-2000

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Table 7.   Monthly means of prevailing wind direction and mean wind speed recorded at the Observatory and Waglan Island between 1971-2000
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Month
Observatory Waglan Island
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Prevailing
Direction
(deg.)
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Mean Wind
Speed (km/h)
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Prevailing
Direction
(deg.)
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Mean Wind
Speed (km/h)
January 090 11.0 070 25.4
February 090 12.1 070 25.1
March 090 12.6 070 23.5
April 090 11.7 070 21.2
May 090 10.8 080 20.2
June 090 11.0 230 23.3
July 090 10.9 230 21.9
August 090 10.2 240 20.0
September 090 11.0 090 22.8
October 090 12.4 080 28.7
November 090 10.9 080 27.9
December 090 10.3 070 26.5
Year 090 11.2 070 23.9

Figure 7. Monthly means of prevailing wind direction and mean wind speed recorded at the Observatory and Waglan Island between 1971-2000

Figure 7.   Monthly means of prevailing wind direction and mean wind speed recorded at the Observatory and Waglan Island between 1971-2000

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Table 8.   Monthly mean of atmospheric pressure recorded at the Observatory between
1971-2000
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Month
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Mean (hPa)
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Mean Diurnal
Range (hPa)
January 1020.1 4.1
February 1018.6 4.2
March 1016.1 4.2
April 1012.8 3.9
May 1009.4 3.4
June 1006.2 3.2
July 1005.5 3.4
August 1005.1 3.5
September 1009.2 3.5
October 1014.0 3.6
November 1018.0 3.8
December 1020.5 4.0
Year 1013.0 3.7

Figure8. Monthly mean of atmospheric pressure recorded at the Observatory between 1971-2000

Figure8.   Monthly mean of atmospheric pressure recorded at the Observatory between 1971-2000

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Table 9.   Monthly means of sea surface temperature recorded at North Point and Waglan Island, and evaporation and potential evapotranspiration recorded at King's Park between 1971-2000
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Month
Sea Surface Temperature (deg. C) Evaporation
(mm)
Potential
Evapotranspiration
(mm)
North Point * Waglan Island
 0700 hours   1400 hours  0700 or
 1100 hours 
1400 or
 1700 hours 
January 17.5 17.7 17.5 17.7 80.7 57.9
February 16.7 17.0 16.6 16.7 67.6 53.0
March 17.9 18.2 17.6 17.8 78.1 63.5
April 20.9 21.3 20.7 20.9 93.2 80.0
May 24.5 25.0 24.5 24.7 118.4 98.3
June 26.5 26.9 26.6 26.9 129.0 112.7
July 26.6 27.1 27.2 27.5 155.5 131.6
August 26.5 27.0 27.1 27.4 143.2 120.9
September 27.1 27.5 27.5 27.7 134.2 99.0
October 26.3 26.6 26.4 26.6 136.4 92.8
November 23.4 23.6 23.3 23.5 112.5 74.0
December 19.8 20.0 19.7 19.9 94.5 60.8
Year 22.8 23.2 22.9 23.1 1343.4 1044.5

*   1975 - 2004

Figure9.1. Monthly Sea Surface Temperature Recorded at North Point between 1975-2004 and Waglan Island between 1971-2000

Figure9.1.   Monthly Sea Surface Temperature Recorded at North Point between 1975-2004 and Waglan Island between 1971-2000

Figure9.2. Monthly means of evaporation and potential evapotranspiration recorded at King's Park between 1971-2000

 

Figure9.2.   Monthly means of evaporation and potential evapotranspiration recorded at King's Park between 1971-2000

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Table 10.   Monthly mean of soil temperature recorded at the Observatory between 1971-2000
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Month
0.5 m 1.0 m 1.5 m
 0700 hours 
(deg. C)
 1900 hours 
(deg. C)
 0700 hours 
(deg. C)
 1900 hours 
(deg. C)
 0700 hours 
(deg. C)
 1900 hours 
(deg. C)
January 18.8 18.8 20.3 20.4 21.6 21.6
February 18.9 18.9 19.8 19.9 20.8 20.8
March 20.6 20.7 20.8 20.8 21.1 21.1
April 23.4 23.5 22.8 22.8 22.5 22.5
May 26.5 26.6 25.5 25.6 24.8 24.8
June 28.5 28.5 27.5 27.5 26.7 26.8
July 29.8 29.9 29.0 29.0 28.2 28.2
August 30.0 30.0 29.4 29.4 29.0 29.0
September 29.6 29.6 29.3 29.4 29.1 29.1
October 27.7 27.7 28.1 28.1 28.2 28.2
November 24.4 24.3 25.6 25.5 26.3 26.3
December 20.5 20.5 22.4 22.4 23.6 23.6
Year 24.9 25.0 24.9 25.0 25.0 25.1


Monthly mean of soil temperature recorded at the Observatory between 1971-2000

Figure10.   Monthly mean of soil temperature recorded at the Observatory between 1971-2000

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Last revision date: <14 Aug 2014>