W
E A T H E R
D
A T A
M
E A S U R E D
& C
A L C U L A T E D
Wind
25
Three special alarms
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ETo (Evapotranspiration)
ETo is updated only once an hour, on the hour. If during a given hour the
ETo Value exceeds the alarm threshold, the ETo alarm sounds at the end of
that hour. This is true for daily, monthly, and yearly ETo alarms. You must
have the optional Solar Radiation Sensor to use this alarm.
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Barometric Pressure
The Weather Envoy allows you to set two barometric pressure alarms: a
“rise” alarm and a “fall” alarm. You may select any rate of change per hour
between 0.01 to 0.25 in Hg (0.1 to 6.4 mm Hg, 0.1 to 8.5 hPa/mb ); the
alarm will sound if the rate of change (in the selected direction) exceeds
the threshold you set.
▲
Time
The time alarm is a standard “alarm clock” alarm. It will sound at the time
you’ve set. Make sure you choose am or pm, if you’re in 12-hour mode. It
will sound for one minute.
We a t h e r D a ta M e a s u r e d &
C a l c u l a t e d
This section outlines each of the weather conditions measured and/or calculated
by the Weather Envoy, by the Vantage Pro Integrated Sensor Suite (ISS), and by
optional Vantage Pro sensors. Each section includes a brief discussion of the
weather condition and a listing of the various ways in which the unit displays or
stores that condition. Be aware that some of the weather conditions require an
optional sensor in order to measure or calculate a value.
Wi n d
The anemometer measures wind speed and the direction from which it’s blowing.
Te m p e r a t u r e
The Weather Envoy uses the ISS’s temperature sensor to measure the outside air
temperature. A second temperature sensor in the Weather Envoy measures the
inside air temperature. Additional temperature sensors (available only with
wireless Vantage Pro and Weather Evnoy systems) can be used to measure
temperature in other locations. You may use these extra sensors to measure any
other temperatures that are within the sensor’s range, including liquids such as
water.
A p pa r e n t Te m p e r a t u r e s
The Weather Envoy calculates three apparent temperature readings: wind chill,
heat index, and the temperature/humidity/wind index (THW Index).
