1. What is the Heat Index?

Definition: The heat index (HI) is a measure of how hot it feels when relative humidity is factored with the actual air temperature.

Purpose: It helps people understand the perceived temperature and potential health risks from heat exposure.

2. How Does the Calculator Work?

The calculator uses the Rothfusz regression equation:

Where:

• \( HI \) — Heat index (°F)
• \( T \) — Temperature (°F)
• \( R \) — Relative humidity (%)
• \( c_1-c_9 \) — Constants (dimensionless)

Note: This formula is valid for temperatures ≥ 80°F and humidity between 0% and 100%.

3. Importance of Heat Index

Details: The heat index helps assess heat-related health risks. Higher values indicate greater risk of heat exhaustion, heat stroke, and other heat-related illnesses.

4. Using the Calculator

Tips: Enter the air temperature in °F and relative humidity in percentage. The calculator will show the "feels like" temperature.

5. Frequently Asked Questions (FAQ)

Q1: Why is heat index higher than actual temperature?
A: High humidity reduces the body's ability to cool through sweat evaporation, making it feel hotter than the actual temperature.

Q2: What's considered a dangerous heat index?
A: Heat indices above 103°F are dangerous, and above 125°F are extremely dangerous with high risk of heat stroke.

Q3: Does this work for temperatures below 80°F?
A: The formula is designed for ≥80°F. Below this, the heat index equals the actual temperature.

Q4: How accurate is this calculation?
A: It's very accurate for standard conditions but doesn't account for wind speed, solar radiation, or personal factors.

Q5: What precautions should I take at high heat indices?
A: Stay hydrated, limit outdoor activity, wear light clothing, and seek air-conditioned spaces when possible.