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WSPD

Average Wind Speed (10 m)

The 5-minute average wind speed at a height of 10 meters above the ground. The propeller has a starting threshold of 1 m s-1.

  • The average wind speed is independent of the wind direction.
  • When WSPD is zero, all other wind variables are set to zero.
Type Sensor Used Standards Units Accuracy
Standard - Primary RM Young Wind Monitor, PDF meters per second (m s-1) ± 0.3 m s-1

RM Young Wind Monitor Sensor

WDIR

Average Vector Wind Direction (10 m)

The vector average wind direction at a height of 10 meters above the ground. Note: wind direction always describes the direction from which the wind is blowing. The vane has a starting threshold of 1.1 m s-1.

  • When WSPD is zero, all other wind variables are set to zero.
Type Sensor Used Standards Units Accuracy
Standard - Primary RM Young Wind Monitor, PDF Described in degrees in a circle (from true north), where north is 0 degrees, east is 90 degrees, south is 180 degrees, and west is 270 degrees ±3° (degrees)

RM Young Wind Monitor Sensor

WMAX

Maximum Wind Speed (10 m)

The maximum (or peak) 3 second wind speed observed during a 5-minute interval at a height of 10 meters above ground; it is the largest value observed during the 5 minute averaging interval.

  • WMAX is independent of wind direction.
Type Sensor Used Standard Units
Standard - Primary RM Young Wind Monitor (for Wind Speed), PDF meters per second

RM Young Wind Monitor Sensor

WS2M

Average Wind Speed (2 m)

The 5-minute average wind speed at 2 meters. Because of the characteristic response of the cup design, the Mesonet's dataloggers add 0.2 m s-1 to each observation greater than 0.2 m s-1.

  • The cup anemometer only counts the rotations of the sensor caused by the speed of the wind; it does not measure wind direction. Its range is from 0.5 to 50 m s-1 and it can withstand gusts of 60 m s-1. The two-meter windspeed mainly is used for agricultural purposes (e.g., to help estimate evapotranspiration of moisture from the soil).
Type Sensor Used Standard Units
Standard - Primary RM Young Wind Sentry (for Wind Speed), PDF m s-1

RM Young WInd Sentry Sensor

WVEC

Average Vector Wind Speed (10 m)

The average wind velocity (speed and direction accounted for) at a height of 10 meters above the ground.

  • Note that this is a vector average (i.e., the wind direction is considered). If the wind is out of the north at 10 m s-1 for 2.5 minutes and then out of the south at 10 m s-1 for 2.5 minutes, the average vector wind velocity will be zero during that 5-minute period.
Type Sensor Used Standard Units
Standard - Primary RM Young Wind Monitor (for Wind Speed), PDF meters per second

RM Young Wind Monitor Sensor

WSSD

Wind Speed Standard Deviation (10 m)

The standard deviation of the wind speed at a height of 10 meters above the ground.

  • This variable is a measure of the steadiness of wind speed. A small standard deviation indicates the wind generally blowing at the same speed; a large standard deviation indicates significant changes in wind speed during the 5-minute interval. The standard deviation may be large for inclement weather.
Type Sensor Used Standard Units
Standard - Primary RM Young Wind Monitor (for Wind Speed), PDF meters per second

RM Young Wind Monitor Sensor

WDSD

Wind Direction Standard Deviation (10 m)

The standard deviation of the wind direction at a height of 10 meters above the ground.

  • This variable is a measure of the steadiness of wind direction. A small standard deviation indicates the wind is blowing from the same direction; a large standard deviation indicates significant changes in wind direction during the 5-minute interval. The standard deviation may be large for either inclement weather or relatively light winds.
Type Sensor Used Standard Units
Standard - Primary RM Young Wind Monitor, PDF degrees

RM Young Wind Monitor Sensor