Heat Index
Overview
The heat index is a calculated measure that combines air temperature and relative humidity to estimate how hot conditions feel to the human body. It reflects the reduced effectiveness of sweat evaporation in humid environments.
Key points
- Represents perceived temperature rather than actual air temperature.
- Higher humidity reduces the body’s ability to cool through evaporation.
- Used to assess heat stress risk during warm weather hikes.
- Values above certain thresholds indicate dangerous exertion conditions.
- Commonly referenced in weather advisories and safety guidelines.
Details
The heat index accounts for the interaction between temperature and humidity, providing a practical indicator of thermal discomfort and physiological stress. High humidity limits evaporative cooling, making moderate temperatures feel significantly hotter.
For hikers, understanding the heat index supports planning for hydration, rest intervals, and route choices. Exposure to elevated heat index values increases the risk of heat-related illnesses, requiring caution during warm seasons.
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Illustrative hiking footage
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