ENG-2013 — Page 502

HONG KONG CLIMATE

TEMPERATURE

30

40

RELATIVE HUMIDITY

°C

%

50

90

1981 - 2010

MEAN MONTHLY

RELATIVE HUMIDITY

MÉAN DALY MAY

ONTHLY MEAN MEAN'DAILY MIN

20

20

AIR TEMPERATURE

MONTHLY RAINFALL

mm

1400

1200

1000

80

800

70

600

60

400

200

10

50

MONTH 1 2 3 4 5 6 7 8 9 10 11 12 MONTH

Beaufort Scale and Equivalent Speeds

MONTH

0

1887

1983

1983

2000

1889

8002

1994

1914

1974

1974

1952

1995

1 2 3 4 5 6 7 8 9 10 11 12

Descriptive Terms

Calm

Light

Moderate

Fresh

Strong

Sustained Wind Speed in km/h

0-1

2-12

13-30

31-40

41 - 62

Gale

63-87

Storm

Hurricane

88 - 117 >=118

Beaufort Force

0

1-2

WIND

3-4

N

5

6-7

8-9

10 - 11

12

1-2

3-4 5-6

>=7 Beaufort Force

2-12 13-30 31-50

>=51 Wind speed in km/h

Beaufort Scale - An international system for

describing wind force

km/h - 1 km/h is 1 kilometre per hour

The number in the inner circle is the percentage frequency of occurrence of calm and variable winds

N

WIND ROSE

HONG KONG OBSERVATORY

HEADQUARTERS

(1981-2010)

Data source: Hong Kong Observatory

•15%

-20%-

25%

·30%·

35%

40%

·45%-

E

W

WIND ROSE

WAGLAN ISLAND (1981 - 2010)

0:6

·10%

·15%

-20%

·25%

30%

35%

-40%

·45%

Frequency of Occurrence of Wind Direction and Speed

at the Hong Kong Observatory Headquarters and Waglan Island

Monthly Prevailing Wind Direction and Mean Speed Observed at Waglan Island (1981 - 2010)

km/h 25.3

24.5

23.0

JAN

FEB

MAR

20.9

19.7

APR MAY

22.9

JUN

21.3

19.4

22.6

JUL AUG SEP

27.4

OCT

1995

YEAR RECORDEC

MAXIMUM MONTHLY

(1884 - 1939)

&

(1947 - 2013)

,1997

WETTEST

YEAR

MEAN MONTHLY (1981 - 2010)

RAINFALL

MONTH