The Timex Expedition WS4 is a multifunction digital watch produced by Timex. In addition to regular timekeeping, it features barometer, altimeter, thermometer, compass, and weather forecast functions. "WS4" stands for "Wide Screen 4 Functions". It was introduced in May 2009.
The Timex Expedition WS4 in time display mode. The temperature displays 31.8 degrees Celsius while the clouds and rain icon indicates the barometric pressure trend is negative, forecasting deteriorating weather conditions ahead with possible rain.
The Timex Expedition WS4 in time display mode. The temperature displays 28.1 degrees Celsius while the sun icon indicates the barometric pressure trend is positive, forecasting improving weather ahead. The digital time is also displayed through an LCD watch with analogue hands located on the upper left corner of the dashboard.
Timex Expedition WS4 in barometric chart mode. The trend of the barometric chart is negative, indicating decreasing atmospheric pressure, thus the cloud icon, just above the temperature display, indicates deteriorating or cloudy weather ahead. The time is indicated by the LCD analogue display watch on the upper left corner of the dashboard.
A barometer is a scientific instrument that is used to measure air pressure in a certain environment. Pressure tendency can forecast short term changes in the weather. Many measurements of air pressure are used within surface weather analysis to help find surface troughs, pressure systems and frontal boundaries.
Barometer
Siphon
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Evangelista Torricelli
