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Absolute pressure is the measured atmospheric pressure, and is a function of
altitude, and to a lesser extent, changes in weather conditions.
Absolute pressure is not corrected to sea-level conditions.
Relative pressure is corrected to sea-level conditions. For further discussion of
relative pressure and calibration, reference Section 5.4.3.
5.4.2 Rate of Change of Pressure Graph
The rate of change of pressure graphic is shown to the left of the weather
forecast icons and signifies the difference between the daily average pressure
and the 30-day average (in hPa).
Figure 18
5.4.3 Relative Pressure Calibration Discussion
The calibration was set on WS View app. To compare pressure conditions
from one location to another, meteorologists correct pressure to sea-level
conditions. Because the air pressure decreases as you rise in altitude, the
sea-level corrected pressure (the pressure your location would be at if located
at sea-level) is generally higher than your measured pressure.
Thus, your absolute pressure may read 726. 95 mmHg (969 mb) at an altitude
of 305 m, but the relative pressure is 762 mmHg (1016 mb).
The standard sea-level pressure is 759. 97 mmHg (1013 mb). This is the
average sea-level pressure around the world. Relative pressure measurements
greater than 759. 97 mmHg (1013 mb) are considered high pressure and
relative pressure measurements less than 759. 97 mmHg are considered low
pressure.
To determine the relative pressure for your location, locate an official
reporting station near you (the internet is the best source for real time
barometer conditions, such as Weather. com or Wunderground. com), and set
