Heat Index Chart - Relative Humidity vs. Air Temperature |
As one who is severely discomforted by a combination of heat and humidity, this kind of table is of great
interest. If I am going to be miserable, I want to know exactly how miserable I really am! This information is
derived from
NOAA Click here for a
windchill chart.
Extreme Danger - Heat stroke or sun stroke likely |
Danger - Sunstroke, muscle cramps and/or heat
exhaustion likely |
Extreme Caution - Sunstroke, muscle cramps and/or
heat exhaustion possible |
Caution - Fatigue possible |
|
NOAA provides the following equation for calculating heat index: HI = -42.379 +
2.04901523T + 10.14333127R - 0.22475541TR - 6.83783x10-3T2
- 5.481717x10-2R2 + 1.22874x10-3T2R + 8.5282x10-4TR2
- 1.99x10-6T2R2,
where T = ambient
dry bulb temperature (°F) R = relative humidity (integer percentage)
"Because this equation is
obtained by multiple regression analysis, (HI) has an error of ±1.3°F"
Air Temp (°F) |
Relative Humidity (%) |
|
40 |
45 |
50 |
55 |
60 |
65 |
70 |
75 |
80 |
85 |
90 |
95 |
100 |
110 |
136 |
|
|
|
|
|
|
|
|
|
|
|
|
108 |
130 |
137 |
|
|
|
|
|
|
|
|
|
|
|
106 |
124 |
130 |
137 |
|
|
|
|
|
|
|
|
|
|
104 |
119 |
124 |
131 |
137 |
|
|
|
|
|
|
|
|
|
102 |
114 |
119 |
124 |
130 |
137 |
|
|
|
|
|
|
|
|
100 |
109 |
114 |
118 |
124 |
129 |
136 |
|
|
|
|
|
|
|
98 |
105 |
109 |
113 |
117 |
123 |
128 |
134 |
|
|
|
|
|
|
96 |
101 |
104 |
108 |
112 |
116 |
121 |
126 |
132 |
|
|
|
|
|
94 |
97 |
100 |
102 |
106 |
110 |
114 |
119 |
124 |
129 |
136 |
|
|
|
92 |
94 |
96 |
99 |
101 |
105 |
108 |
112 |
116 |
121 |
126 |
131 |
|
|
90 |
91 |
93 |
95 |
97 |
100 |
103 |
106 |
109 |
113 |
117 |
122 |
127 |
132 |
88 |
88 |
89 |
91 |
93 |
95 |
98 |
100 |
103 |
106 |
110 |
113 |
117 |
121 |
86 |
85 |
87 |
88 |
89 |
91 |
93 |
95 |
97 |
100 |
102 |
105 |
108 |
112 |
84 |
83 |
84 |
85 |
86 |
88 |
89 |
90 |
92 |
94 |
96 |
98 |
100 |
103 |
82 |
81 |
82 |
83 |
84 |
84 |
85 |
86 |
88 |
89 |
90 |
91 |
93 |
95 |
80 |
80 |
80 |
81 |
81 |
82 |
82 |
83 |
84 |
84 |
85 |
86 |
86 |
87 |
|
|
|
 |
 |
 |
 |

Copyright: 1996 - 2024 Webmaster:
Kirt Blattenberger, BSEE - KB3UON |
RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling
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and reference material while performing my work as an RF system and circuit design engineer.
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in the form of WYSIWYG
...
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