Table 4 - Temperature of dew point in degrees Fahrenheit

[Pressure = 25.00 inches]

Air
Temp
t

Vapor
Press.
e

Depression of wet-bulb thermometer (t-t')

6.2 6.4 6.6 6.8 7.0 7.2 7.4 7.6
15 0.0810 -43
16 0.0850 -31 -40 -56
17 0.0891 -25 -29 -36 -49
18 0.0933 -19 -23 -27 -33 -44
19 0.0979 -15 -18 -21 -26 -31 -40 -55  
20 0.1026 -12 -14 -17 -20 -24 -29 -36 -47