NWS New Orleans Heat Index Calculator

Heat Index Formula:

\[ HI = -42.379 + 2.04901523T + 10.14333127RH - 0.22475541T \times RH - 6.83783 \times 10^{-3}T^2 - 5.481717 \times 10^{-2}RH^2 + 1.22874 \times 10^{-3}T^2 \times RH + 8.5282 \times 10^{-4}T \times RH^2 - 1.99 \times 10^{-6}T^2 \times RH^2 \]

Heat Index:

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1. What is the NWS New Orleans 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 assess the risk of heat-related illnesses during hot weather, especially important in humid climates like New Orleans.

2. How Does the Calculator Work?

The calculator uses the standard NWS heat index formula:

\[ HI = -42.379 + 2.04901523T + 10.14333127RH - 0.22475541T \times RH - ... \]

Where:

\( HI \) — Heat Index (°F)
\( T \) — Temperature (°F)
\( RH \) — Relative Humidity (%)

Explanation: The formula calculates the apparent temperature based on how humidity affects the body's ability to cool itself through sweat evaporation.

3. Importance of Heat Index

Details: The heat index helps determine heat safety precautions. Values above 90°F increase risk of heat-related illness, while values above 103°F are dangerous.

4. Using the Calculator

Tips: Enter temperature (≥80°F) and relative humidity (0-100%). The calculator is only valid for temperatures ≥80°F.

5. Frequently Asked Questions (FAQ)

Q1: Why is this specific to New Orleans?
A: The NWS formula is standard, but New Orleans' high humidity makes heat index particularly important for residents and visitors.

Q2: What are the health risk categories?
A: Caution (80-90°F), Extreme Caution (90-103°F), Danger (103-124°F), Extreme Danger (125°F+).

Q3: Does wind speed affect heat index?
A: The standard formula doesn't include wind, but breezes can make it feel cooler than the calculated index.

Q4: Why is humidity so important?
A: High humidity reduces sweat evaporation, the body's primary cooling mechanism in hot weather.

Q5: What's the highest possible heat index?
A: There's no theoretical maximum, but values above 130°F are extremely rare and life-threatening.