EXTRACT OF METEOROLOGICAL OBSERVATIONS FOR HONG KONG, APRIL 2011
EXTRACT OF METEOROLOGICAL OBSERVATIONS FOR HONG KONG,
APRIL 2011
| Date APRIL |
Mean Pressure (hPa) |
Air Temperature |
Mean Dew Point Temperature (deg. C) |
Mean Relative Humidity (%) |
Mean Amount of Cloud (%) |
Total Rainfall (mm) |
||
|---|---|---|---|---|---|---|---|---|
|
Maximum (deg. C) |
Mean (deg. C) |
Minimum (deg. C) |
||||||
| 1 | 1016.5 | 26.0 | 20.5 | 16.9 | 14.6 | 70 | 21 | - |
| 2 | 1014.8 | 27.4 | 22.0 | 19.0 | 16.4 | 72 | 20 | - |
| 3 | 1013.6 | 26.7 | 22.2 | 19.4 | 17.8 | 77 | 41 | Trace |
| 4 | 1016.8 | 21.9 | 19.7 | 18.4 | 16.7 | 83 | 92 | Trace |
| 5 | 1018.9 | 20.5 | 18.9 | 17.7 | 14.1 | 74 | 90 | Trace |
| 6 | 1018.0 | 23.7 | 19.6 | 17.4 | 12.7 | 66 | 65 | - |
| 7 | 1016.8 | 27.0 | 21.8 | 18.9 | 17.4 | 77 | 41 | - |
| 8 | 1017.3 | 28.4 | 23.1 | 19.6 | 17.6 | 73 | 16 | - |
| 9 | 1019.4 | 27.1 | 22.5 | 20.2 | 18.2 | 77 | 60 | Trace |
| 10 | 1018.1 | 29.7 | 23.4 | 20.6 | 19.0 | 77 | 41 | Trace |
| 11 | 1015.3 | 29.1 | 23.8 | 20.6 | 19.3 | 77 | 24 | Trace |
| 12 | 1017.8 | 25.8 | 22.0 | 20.5 | 16.8 | 73 | 76 | - |
| 13 | 1016.7 | 28.5 | 23.0 | 20.2 | 15.4 | 64 | 64 | Trace |
| 14 | 1012.7 | 29.6 | 24.1 | 21.0 | 19.1 | 75 | 36 | - |
| 15 | 1010.3 | 29.4 | 24.4 | 22.0 | 20.0 | 77 | 64 | - |
| 16 | 1010.0 | 28.2 | 25.1 | 22.7 | 21.6 | 82 | 63 | - |
| 17 | 1008.7 | 28.1 | 24.8 | 22.9 | 23.3 | 91 | 92 | 26.7 |
| 18 | 1010.1 | 27.0 | 23.6 | 21.7 | 19.2 | 77 | 81 | Trace |
| 19 | 1014.4 | 27.5 | 23.6 | 21.3 | 16.1 | 64 | 38 | - |
| 20 | 1016.8 | 24.6 | 21.8 | 20.5 | 17.4 | 77 | 80 | - |
| 21 | 1014.7 | 27.1 | 23.1 | 21.0 | 19.5 | 81 | 73 | Trace |
| 22 | 1011.6 | 28.2 | 24.1 | 21.7 | 20.0 | 79 | 67 | 0.2 |
| 23 | 1014.1 | 23.2 | 20.9 | 19.7 | 18.1 | 85 | 84 | 2.3 |
| 24 | 1014.6 | 28.4 | 23.1 | 19.7 | 11.6 | 50 | 32 | - |
| 25 | 1012.8 | 28.9 | 24.1 | 20.9 | 17.0 | 65 | 31 | - |
| 26 | 1010.0 | 28.0 | 24.2 | 21.7 | 17.6 | 68 | 48 | - |
| 27 | 1007.8 | 29.1 | 25.9 | 23.4 | 21.4 | 77 | 67 | - |
| 28 | 1010.0 | 27.6 | 25.1 | 23.6 | 22.8 | 87 | 89 | 0.4 |
| 29 | 1011.6 | 23.9 | 23.1 | 22.5 | 21.9 | 93 | 95 | 6.3 |
| 30 | 1010.7 | 27.1 | 24.9 | 23.2 | 22.4 | 86 | 85 | 0.1 |
| Mean/Total | 1014.0 | 26.9 | 22.9 | 20.6 | 18.2 | 76 | 59 | 36.0 |
| Normal* | 1012.8 | 25.1 | 22.5 | 20.6 | 19.4 | 83 | 80 | 188.5 |
| Station | Hong Kong Observatory | |||||||
| Date APRIL |
Number of hours of Reduced Visibility# (hours) |
Total Bright Sunshine (hours) |
Daily Global Solar Radiation (MJ/m2) |
Total Evaporation (mm) |
Prevailing Wind Direction (degrees) |
Mean Wind Speed (km/h) |
|---|---|---|---|---|---|---|
| 1 | 0 | 11.2 | 25.24 | 4.8 | 050 | 19.3 |
| 2 | 7 | 10.7 | 24.34 | 5.1 | 050 | 11.5 |
| 3 | 0 | 9.3 | 20.23 | 3.6 | 220 | 5.3 |
| 4 | 9 | - | 3.36 | 1.7 | 080 | 25.6 |
| 5 | 3 | 2.5 | 14.01 | 4.3 | 090 | 37.4 |
| 6 | 0 | 6.0 | 17.78 | 3.5 | 070 | 30.7 |
| 7 | 0 | 10.6 | 22.64 | 3.9 | 050 | 13.9 |
| 8 | 0 | 10.2 | 20.25 | 5.4 | 030 | 5.0 |
| 9 | 0 | 6.5 | 19.05 | 2.4 | 080 | 23.3 |
| 10 | 7 | 9.2 | 22.93 | 5.5 | 050 | 14.4 |
| 11 | 3 | 11.2 | 23.36 | 4.6 | 220 | 17.2 |
| 12 | 17 | 6.6 | 18.03 | 5.0 | 070 | 35.5 |
| 13 | 0 | 5.7 | 17.71 | 3.4 | 060 | 16.8 |
| 14 | 0 | 9.2 | 19.34 | 3.9 | 170 | 8.5 |
| 15 | 2 | 6.2 | 16.82 | 3.4 | 220 | 8.3 |
| 16 | 1 | 5.4 | 17.60 | 4.1 | 230 | 16.7 |
| 17 | 0 | 0.9 | 7.21 | 5.1 | 230 | 20.7 |
| 18 | 1 | 1.9 | 11.68 | 3.7 | 050 | 15.3 |
| 19 | 1 | 9.0 | 22.41 | 5.2 | 080 | 26.6 |
| 20 | 0 | 3.6 | 13.44 | 3.2 | 070 | 34.2 |
| 21 | 0 | 8.2 | 22.23 | 4.1 | 070 | 23.7 |
| 22 | 0 | 6.0 | 18.61 | 2.9 | 040 | 11.5 |
| 23 | 4 | - | 3.21 | 2.9 | 040 | 22.0 |
| 24 | 0 | 11.0 | 25.85 | 5.4 | 050 | 14.0 |
| 25 | 1 | 10.9 | 23.47 | 4.8 | 010 | 7.1 |
| 26 | 0 | 10.9 | 22.95 | 6.0 | 220 | 12.5 |
| 27 | 2 | 8.2 | 20.12 | 3.3 | 240 | 22.9 |
| 28 | 10 | 0.1 | 7.95 | 1.4 | 100 | 18.4 |
| 29 | 5 | - | 3.72 | 1.5 | 090 | 25.6 |
| 30 | 3 | 0.4 | 9.31 | 1.4 | 170 | 8.3 |
| Mean/Total | 76 | 191.6 | 17.16 | 115.5 | 070 | 18.4 |
| Normal* | 100.1§ | 101.8 | 11.83 | 93.2 | 070 | 21.2 |
| Station | Hong Kong International Airport |
King's Park | Waglan Island^ | |||
The minimum pressure recorded at the Hong Kong Observatory was 1005.7 hectopascals at 1615 HKT on 27 April.
The maximum air temperature recorded at the Hong Kong Observatory was 29.7 degrees C at 1412 HKT on 10 April.
The minimum air temperature recorded at the Hong Kong Observatory was 16.9 degrees C at 0621 HKT on 1 April.
The maximum gust peak speed recorded at Waglan Island was 83 kilometres per hour from 220 degrees at 1611 HKT on 17 April.
The maximum instantaneous rate of rainfall recorded at the Hong Kong Observatory was 134 millimetres per hour at 1550 HKT on 17 April.
# Reduced visibility refers to visibility below 8 kilometres when there is no fog, mist, or precipitation.
-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.
^ In case the data are not available from Waglan Island, observations of Cheung Chau or other nearby weather stations will be incorporated in computing the Prevailing Wind Direction and Mean Wind Speed.
* 1971-2000 Climatological Normal, unless otherwise specified
§ 1997-2010 Mean value