nephoscope
/ˈnɛfəskəʊp/Definitions
1. noun
An instrument for determining the direction of cloud movements or of atmospheric currents, by observing the shadows cast by clouds on the ground or on a distant object.
“A nephoscope was used to predict the direction of the storm’s winds.”
2. noun
A device used to measure wind direction or atmospheric conditions in relation to weather forecasting.
“The meteorologist studied the nephoscope readings to make an accurate weather forecast.”