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Temp dew point spread

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What is the temp/dew point spread?

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1 Answers



  1. Tom Kelley on Aug 22, 2013

    This is the difference in temperature between the actual temperature and the “dew point” temperature at that same time. The dew point temperature is the temperature at which the air becomes 100% saturated with moisture (water), so it turns to fog at that temperature. So the dryer the air, the larger the spread between these two temperatures. On the other hand, when the two temperatures are close, it means pilots need to be very careful as visibility can be severely reduce, all the way to complete fog.
    As an example, if the temperature is 80 degrees and the dew point is 78 degrees, it means that if the air cools off to 78, you can expect very poor visibility.

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