Tennessee design temperatures
Outdoor heating and cooling design conditions for 7 Tennessee weather stations. Choose the station nearest to you in distance and elevation, and check whether your building department specifies its own values.
| Station | Elevation | 99.6 % heating | 99 % heating | 1 % cooling / MCWB | 0.4 % cooling / MCWB | Use it |
|---|---|---|---|---|---|---|
| Bristol/Tri-CityWMO 723181 · 1973–1996 | 1,519 ft | 9 °F | 14 °F | 87 / 72 °F | 90 / 73 °F | Load calculator |
| Chattanooga/LovellWMO 723240 · 1973–1996 | 689 ft | 15 °F | 20 °F | 92 / 75 °F | 95 / 76 °F | Load calculator |
| Jackson/McKellarWMO 723346 · 1973–1996 | 433 ft | 12 °F | 17 °F | 93 / 77 °F | 95 / 78 °F | Load calculator |
| KnoxvilleWMO 723260 · 1973–1996 | 981 ft | 13 °F | 18 °F | 90 / 75 °F | 93 / 75 °F | Load calculator |
| MemphisWMO 723345 · 1973–1996 | 322 ft | 13 °F | 19 °F | 95 / 77 °F | 97 / 77 °F | Load calculator |
| Memphis Intl ArptWMO 723340 · 1973–1996 | 285 ft | 17 °F | 21 °F | 94 / 78 °F | 96 / 78 °F | Load calculator |
| NashvilleWMO 723270 · 1973–1996 | 591 ft | 11 °F | 16 °F | 92 / 75 °F | 95 / 76 °F | Load calculator |
Using these values
- Heat-loss calculations for homes commonly use the 99 % heating value, and cooling loads the 1 % dry bulb with its mean coincident wet bulb (MCWB). The 99.6 % and 0.4 % values are more conservative.
- “Load calculator” opens the heating and cooling load calculator with that station’s 99 % and 1 % temperatures and its design moisture difference (outdoor air at the 1 % condition versus 75 °F, 50 % RH indoors, at the station’s elevation).
- Source: U.S. Air Force Combat Climatology Center and NOAA National Climatic Data Center, Engineering Weather Data (1999; public domain). Each station’s period of record is shown under its name; they end by 1996, and the climate has warmed since, so check local requirements before relying on a value for a permit.