 The Heat Index ChartThe Heat Index is a function of temperature and relative humidity. The combination of the two results in an apparent temperature which gives an idea of what it would feel like under normal-to-low humidity conditions. The heat index also applies to shady, light wind conditions, so it feels even hotter than the heat index if a person is in direct sun. In the midst of a hot, dry, wind a person would also feel hotter than the heat index value due to the wind effects. Excessive and dangerous heat indices occur mostly during the summer months with the abundance of moisture and increased heat. 
Apparent Temperature Readings- Caution 85 to 94°F physical activity may cause fatigue
- Extreme Caution 95 to 105°F possible heat cramps and/or heat exhaustion with prolonged exposure
- Danger Above 105°F possible heat stroke with prolonged exposure; heat exhaustion and heat cramps likely
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