Heat – Humidity Factor

In order to determine a “Heat Factor”, locate the measured outside temperature row and then the humidity column and then read the corresponding apparent temperature at the intersection of the row and column. This “Heat Factor” is the combined effect of actual temperature and humidity that makes the measured outside temperature “feel” hotter. Heat exhaustion danger occures when the “Heat Factor” is greater than 105 F
Measured Percent Relative Humidity
Temp °F 0 10 20 30
70 64 65 66 67
75 69 70 72 73
80 73 75 77 78
85 78 80 82 84
90 83 85 87 90
95 87 90 93 96
100 91 95 99 104
105 95 100 105 113
110 99 105 112 123
115 103 111 120 135
120 107 116 130 148
 
Measured Percent Relative Humidity
Temp °F 40 50 60 70
70 68 69 70 70
75 74 75 76 77
80 79 81 82 85
85 86 88 90 93
90 93 96 100 106
95 101 107 114 124
100 110 120 132 144
105 123 135 149  
110 137 150    
115 151      
 
Measured Percent Relative Humidity
Temp °F 80 90 100  
70 71 71 72  
75 78 79 80  
80 86 88 91  
85 97 102 108  
90 113 122    
95 136