Heat Index Deep Calculator
Calculate the heat index using the full Rothfusz regression equation with NWS adjustments. Includes risk assessment and exposure-duration guidance.
Inputs
Results
Heat Index
117.6 °F
NWS Risk Level
Danger — Heat cramps/exhaustion likely, heatstroke possible
How to Use This Calculator
- Enter air temperature (°F) and relative humidity (%) for your location.
- Set exposure duration (hours) to assess cumulative heat stress risk.
- Review Heat Index (°F) — this is the apparent temperature felt by the body.
- Check NWS Risk Level and Exposure Risk to understand danger thresholds: above 103°F = danger, 125°F+ = extreme danger.
- Use Recommended Water Intake (liters) as a hydration planning guide for workers or athletes outdoors.
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