change from “sunny” directly to “clouds with rain” although it is possible for the change to occur quickly. If the symbols do not change then the weather has not changed or the change has been slow and gradual. If this happens on a regular basis, it may be necessary to adjust the weather forecast sensitivity.
C.WEATHER TENDENCY ARROWS
Another icon in the tendency LCD is weather tendency arrows, one that points up and one that points down. These arrows reflect current changes in the air pressure: an arrow pointing up indicates that the air pressure is increasing and the weather is expected improve or remain good. An arrow pointing down indicates that the air pressure is decreasing and the weather is expected to become worse or remain poor. No arrow means the pressure is stable.
A storm can be expected if there is a drop of 4 hPa or more in less than 6 hours, the rain icon is displayed and the downward pointing arrow is flashing. The flashing will stop when the air pressure stabilizes or begins to rise.
D.AIR PRESSURE HISTORY BAR GRAPH
The bar graph shows in hPa the recorded air pressure over the past 72 hours. The horizontal axis shows the hours at the increments of 72h, 48h, 36h, 24h, 18h, 12h, 9h, 6h, 3h, 1h, and 0h (0h is the current hPa). The vertical axis is set by hPa: 0 is the current hPa and + or – or
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