WIND

the dreamcatcher Ok, so you have you just gone out and on a whim bought yourself a new or used sailboat because you thought sailing and boating looked to be fun and enticing.

So you are now on that new boat you have just purchased and you suddenly realize that the motor does not work or that there is not even a motor on it. All you have is a boat with a tall stick standing up with another stick coming off of it in a perpendicular manner and attached to these two sticks is a bunch of cloth.

Perhaps you need to take Sailing Lessons? Or perhaps you just need to learn about wind and how it makes that new boat of yours move through the water.

Below, you will find links on Wind, what it is and how you need to know how to use it.

 

LINKS TO WIND INFORMATION
Beaufort Scale - Wind Conditions

National Digital Forecast Database Graphical Forecast Key - Provides definitions used by the NWS forecasting office.

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Estimating Wind Speed - National Weather Service  
   

WIND CHILL

Wind Chill - NWS - Provides calculator tool

Wind Chill Chart - Provides information on how the NWS Wind Chill Chart was developed

 

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Wind Barbs

Indicators of wind direction and speed



Wind barbs are simply a conventient way to represent both wind speed and direction in a compact graphical form. Vectors also work to some degree but it is more difficult to discern the magnitude when viewing vectors. For this reason, meteorologists prefer the use of wind barbs. The graphic illustrates shows how to read a wind barb. Meteorologists are also accustomed to nautical miles per hour (knots) for the magnitude of the wind.

The station model plotted on surface weather maps uses a wind barb to show both wind direction and speed. The wind barb shows the speed using "flags" on the end.

  • Each half of a flag depicts a wind speed of 5 knots or 9.3 km per hour.
  • Each full flag depicts a wind speed of 10 knots or 19 km/h of wind.
  • Each pennant (filled triangle) depicts a wind speed of 50 knots or 93 km per hour

Winds are depicted as blowing from the direction the barb is facing. Therefore, a northeast wind will be depicted with a line extending from the cloud circle to the northeast, with flags indicating wind speed on the northeast end of this line. When wind speed is plotted on a map, lines connecting equal wind speed at various stations(TERMED isotachs lines) (lines of equal wind speeds) can be drawn. Isotach lines are particularly useful in diagnosing the location of the jet stream on upper level constant pressure charts, and are usually located at or above the 300 hPa level.

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WIND SPEED CONVERSION

Convert to statute miles per hour (mph) by adding 15% to the value in knots. Example: 60 knots = 60 + 9 mph. [Just remember to figure it the same way you would figure a 15% tip at a restaurant by taking 10% and then halve that value   ;-)   ]

Information and Data Sources:

  1. http://en.wikipedia.org/wiki/Wind;
  2. http://www.rap.ucar.edu/weather/info/about_windbarb.html