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')
16.5 17.0 17.5 18.0 18.5 19.0 19.5 20.0 20.5 21.0 21.5 22.0 22.5 23.0 23.5 24.0
45 0.298 -50
46 0.310 -25 -58                            
47 0.322 -15 -27
48 0.334 -8 -16 -29
49 0.347 -3 -9 -17 -30
50 0.360 +1 -4 -9 -17 -32
51 0.373 4 0 -4 10 -18 -34                    
52 0.387 7 +4 0 -5 -11 -20 -37
53 0.402 10 7 +4 0 -5 -12 -21 -42
54 0.417 12 10 7 +3 -1 -6 -12 -22 -46
55 0.432 15 12 10 7 +3 -1 -6 -13 -23 -50
56 0.448 17 15 12 10 7 +3 -1 -6 -14 -24 -57          
57 0.465 19 17 15 12 10 7 +3 -2 -7 -14 -25
58 0.482 21 19 17 15 12 10 6 +3 -2 -7 -15 -27
59 0.499 23 21 19 17 15 12 10 7 +3 -2 -7 -15 -28
60 0.517 25 23 21 19 17 15 12 10 7 +3 -2 -7 -15 -29
61 0.536 27 25 23 21 19 17 15 13 10 7 +3 -2 -8 -16 -29  
62 0.555 28 27 25 23 22 20 17 15 13 10 7 +3 -2 -8 -16 -29
63 0.575 30 28 27 25 24 22 20 18 15 13 10 7 +3 -2 -8 -16
64 0.595 32 30 29 27 25 24 22 20 18 16 13 10 7 +3 -2 -8
65 0.616 33 32 30 29 27 26 24 22 20 18 16 13 10 7 +3 -2
66 0.638 35 33 32 30 29 27 26 24 22 20 18 16 13 10 7 +3
67 0.661 36 35 33 32 31 29 28 26 24 23 21 18 16 13 10 7
68 0.684 38 37 35 34 32 31 29 28 26 24 23 21 19 16 14 11
69 0.707 39 38 37 35 34 32 31 30 28 26 25 23 21 19 16 14
70 0.732 41 40 38 37 36 34 33 31 30 28 27 25 23 21 19 17
71 0.757 42 41 40 39 37 36 34 33 32 30 29 27 25 23 22 19
72 0.783 44 43 42 40 39 38 36 35 33 32 30 29 27 26 24 22
73 0.810 45 44 43 42 41 39 38 37 35 34 32 31 29 28 26 24
74 0.838 47 46 44 43 42 41 40 38 37 36 34 32 31 29 28 26
75 0.866 48 47 46 45 44 42 41 40 38 37 36 34 33 31 30 28
76 0.896 50 49 47 46 45 44 43 42 40 39 38 36 35 33 32 30
77 0.926 51 50 49 48 47 46 44 43 42 41 39 38 36 35 34 32
78 0.957 52 51 50 49 48 47 46 45 44 42 41 40 38 37 35 34
79 0.989 54 53 52 51 50 48 47 46 45 44 43 41 40 39 37 36
80 1.022 55 54 53 52 51 50 49 48 46 45 44 43 42 40 39 38