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 | Wind Speed and Direction |  |
As a general rule of thumb I have found that if the Wind Speed at the Airport is around 10kts the wind speed at the sites around the coast is usually around 12-15kts and soarable! (See the conversion calculators below.)
Basically you are looking for a wind speed of force 3-4 (See below for a guide to the Beaufort Scale)
A force 1-2 wind and it may be possible to top to bottom.(Bonne Nuit site gives about a 3 minute flight to beach)
Wind Direction at the Airport is usually pretty accurate for all sites!
You can find out the current wind at the Airport by calling the Duty Met Forecaster or check out the Jersey Meteorological Department's Internet Website for a local forecast (Updated four times daily).
Another, more acurate, way to get an actual weather report is to go to AvBrief Aviation and Weather page. You will need to register to get the service but it remains free for the basic services.
Once registered enter EGJJ into the airport box and submit.
The information displayed is for Jersey airport and the bit you will be interested in is the METAR. This is the half hourly actual weather conditions from Jersey airport.
METAR Example:-
160820 EGJJ 03010KT CAVOK 17/10 Q1020 NOSIG=
Decoding the information!
The first set of 6 numbers is the date and time of the observation. In the above example 16 is the 16th day of the month, the 0820 is the time of the observation.
EGJJ is the standard coding for Jersey Airport. ie what pilots use to identify Jersey on a flight plan.
The next 5 digits followed by the KT is the WIND DIRECTION AND SPEED! (The bit we are interested in!). The example shows a wind direction of 030 degrees and a speed of 10Knots.(You can use my converter at the bottom of this page to change knots to Mph or Kph)
The next bit of information shown is the cloud coverage - CAVOK means no significant cloud below 5000ft.
The four figures separated by the / indicate the temperature and dew point. In the example the temperature is 17° C and dew point is 10° C.
The four numbers after the Q show the current Sea level Pressure. In the example 1020 millibars.
The NOSIG bit of the message is the trend for the newxt 2hrs. NOSIG means No Significant Change.
There are many different items that can be shown in a METAR to describe the current weather situation and eventually I will post a complete decode description but for now the fact that you should be able to extract the wind direction and speed is all you really need.
| The Beaufort Scale | |
Observed Effects for various Wind Speeds and Beaufort/Force scale
Kph and Kts rounded figures (mph used for Beaufort Scale)
Visual Clues
On Land |
Visual Clues
Sea Conditions |
WindSpeed
Mph |
Wind Speed
Kph |
Wind Speed
Knots |
Force |
Met. Description |
Still Air,
Smoke rises vertically. |
Mirror like water surface. |
<=1mph |
<=2 km/h |
<= 1 kt |
0 |
Calm |
Rising Smoke drifts,
Weather Vane still Inactive. |
Small ripples on surface. |
1 - 3 mph |
2 - 6 Km/h |
1 - 3 kts |
1 |
Light Air |
Leaves Rustle,
You can feel the wind on your face,
Weather Vane is still Inactive. |
Small glassy wavelets. |
4 - 7 mph |
6 - 11 Km/h |
4 - 6 kts |
2 |
Light Breeze |
Leaves and Twigs move around,
Light weight flags extend. |
Large wavelets,
Some white caps. |
8 - 11 mph |
12 - 19 Km/h |
7 - 10 kts |
3 |
Gentle Breeze |
Thin branches move,
Wind may raise dust and paper. |
Small waves,
Frequent white caps. |
12 - 18 mph |
20 - 30 Km/h |
11 - 16 kts |
4 |
Moderate Breeze |
| Small trees sway. |
Moderate waves,Many white caps,
Some spray possible. |
19 - 24 mph |
31 - 39 Km/h |
17 - 21 kts |
5 |
Fresh Breeze |
Large tree branches move,
Exposed wire may whistle. |
Large waves, All white caps,
Some spray. |
25 - 31 mph |
40 - 50 Km/h |
22 - 27 kts |
6 |
Strong Breeze |
Large trees sway,
Resistance felt when walking. |
Seas heap up the waves,
Some foam streaks off waves. |
32 - 38 mph |
51 - 61 Km/h |
28 - 33 kts |
7 |
Near Gale |
Small Branches brake from trees,
Walking into wind is difficult. |
Moderately high waves, Crests break,
Foam makes well defined streaks. |
39 - 46 mph |
62 - 74 Km/h |
34 - 40 kts |
8 |
Gale |
| Slight damage to buildings |
High waves with dense streaks of spray,
Visability affected. |
47 - 54 mph |
75 - 87 Km/h |
41 - 47 kts |
9 |
Strong Gale |
Trees uprroted,
Strucural damage likely. |
Very high waves, Surface white,
Visability reduced. |
55 - 63 mph |
88 -101 Km/h |
48 - 55 kts |
10 |
Storm |
| Widespread damage. |
Exceptionally high waves,
Visability limited. |
64 - 73 mph |
102 - 117 Km/h |
56 - 63 kts |
11 |
Violent Storm |
Severe structural damage,
Widespread devastation |
Air is filled with foam and spray,
Sea white, Visability restricted. |
74 - 82+ mph |
118 - 132+ Km/h |
64 - 71+ kts |
12 |
Hurricane |
| Conversion Factors | |
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Nautical Miles per Hour (knots - kts) multiplied by 1.15152 equals Miles per Hour (mph)
Miles per Hour (Mph) divided by 1.15152 equals Nautical Miles per Hour (Knots - kts)
Miles per Hour (Mph) Multiplied by 1.60934 equals Kilometres per hour (Kph)
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| Wind Speed Converter | |
Enter the known wind speed into the relevant line below and click the "Convert Now" button to display equivalent values.
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2001-2014 Darren Dupré |
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