Compute the heat index (apparent temperature) from air temperature and relative humidity using the NWS formula.
高温高湿时计算炎热指数（Heat Index），低温有风时计算风寒指数（Wind Chill）
Constants and standards used on this page with their authoritative sources, for verification and citation.
| Quantity | Value | Unit | Source |
|---|---|---|---|
| Rothfusz regression (this page) | −42.379 + 2.04901523T + 10.14333127R − 0.22475541TR − 6.83783×10⁻³T² − 5.481717×10⁻²R² + 1.22874×10⁻³T²R + 8.5282×10⁻⁴TR² − 1.99×10⁻⁶T²R² | °F | Rothfusz L.P. (1990), NWS Technical Attachment SR 90-23; based on Steadman (1979) |
| Applicability | T ≥ 27 °C (80 °F), RH ≥ 40% | — | NOAA/NWS guidance, regression error about ±1.3 °F |
| Low-humidity adjustment | −[(13−RH)/4]·√[(17−|T_F−95|)/17] | °F | NWS adjustment (RH < 13 and 80 ≤ T_F ≤ 112) |
| High-humidity adjustment | +[(RH−85)/10]·[(87−T_F)/5] | °F | NWS adjustment (RH > 85 and 80 ≤ T_F ≤ 87) |
| Danger category thresholds | 27 / 32 / 41 / 54 (caution / extreme caution / danger / extreme danger) | °C | NOAA/NWS heat index categories (converted from 80/90/105/130 °F) |
| US wind chill (cold branch) | 35.74 + 0.6215T_F − 35.75V^0.16 + 0.4275T_F·V^0.16 | °F (V in mph) | US National Weather Service (2001 revision) |
Note: the heat index assumes shaded, light-wind conditions; direct sun, high radiant load or heavy work raise actual heat strain. For occupational assessment use WBGT (ISO 7243 / GB/T 17244).
体感温度计算是一款科学研究领域的在线工具。科学研究工具，采用标准科学公式，计算精准。