Wind Observations

Wind direction observations are assessed by observing the movement of smoke, trees or lowest cloud, but in this latter case only very low cloud is used - stratus fractus and pannus. Higher clouds often move in a direction much in variance with the wind at lower levels.

All wind force observations at Wolstanton Marsh Weather Station use the Beaufort Wind Scale to record the wind force. As the immediate vicinity is a built environment with quite a lot of trees, the Beaufort Scale is easy to apply, whilst anything other than an anemometer on a tall mast would only yield poor result because of turbulence.

The Beaufort Wind Scale

Force Speed (Knots) Name Description of Effects on Land

0

<1

Calm

Smoke rises vertically

1

1 - 3

Light Air

Direction of wind shown by smoke drift, but not by wind vanes

2

4 - 6

Light Breeze

Wind felt on face; leaves rustle; sensitive vane moved by the wind

3

7 - 10

Gentle Breeze

Leaves and small twigs in constant motion; wind extends light flag

4

11 - 16

Moderate Breeze

Raises dust and loose paper; small branches are moved

5

17 - 21

Fresh Breeze

Small trees in leave begin to sway; crested wavelets on lakes

6

22 - 27

Strong Breeze

Large branches in motion; whistling heard through telegraph wires; umbrellas very awkward to use

7

28 - 33

Near Gale

Whole trees in motion; walking against the wind difficult

8

34 - 40

Gale

Breaks twigs off trees; generally impedes progress

9

41 - 47

Strong Gale

Slight structural damage; chimney pots, slates and tiles removed

10

48 - 55

Storm

Trees uprooted; considerable structural damage 

11

56 - 63

Violent Storm

Very rare inland; extensive damage

12

>=64

Hurricane

Extremely rare inland; limited to coastal fringe, and mountain tops