| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 28°F | 46°F | 36°F | 4.7" |
| February | 31°F | 50°F | 40°F | 4.6" |
| March | 39°F | 60°F | 49°F | 5.7" |
| April | 48°F | 71°F | 59°F | 5.8" |
| May | 55°F | 76°F | 65°F | 4.4" |
| June | 62°F | 82°F | 72°F | 5.0" |
| July | 66°F | 84°F | 75°F | 6.8" |
| August | 65°F | 84°F | 74°F | 3.8" |
| September | 58°F | 79°F | 68°F | 4.1" |
| October | 47°F | 70°F | 58°F | 3.6" |
| November | 38°F | 59°F | 48°F | 4.8" |
| December | 33°F | 50°F | 41°F | 6.4" |
| Index | Spencer | Tennessee | National |
| Air quality index | 25 | 76 | 42 |
| Pollution index | 553,508 | 2,454,916 | 2,726,193 |
| Measurement | Total |
| Days measured | 360 |
| Days with good air quality | 351 |
| Days with moderate air quality | 9 |
| Days w/ poor A.Q. for sensitive groups | 0 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.000% |
| Benzene | 0.010% |
| Carbon Tetrachloride | 0.002% |
| Lead | 0.004% |
| Mercury | 0.000% |
| City | Population | Air Quality Index | National Avg. |
| Sparta, TN | 4,942 | 25 | 50.0% |
| Doyle, TN | 589 | 25 | 50.0% |
| Pikeville, TN | 2,465 | 30 | 40.0% |
| Spencer, TN | 1,387 | 25 | 50.0% |
| City | Population | Air Quality Index | National Avg. |
| Ferndale, CA | 1,387 | 27 | 46.0% |
| Westwood, CA | 1,387 | 46 | 8.0% |
| New Windsor, MD | 1,387 | 42 | 16.0% |
| Elroy, WI | 1,387 | 35 | 30.0% |
| Powerview-Pine Falls, MB | 1,387 | n/a | |
| Spencer, TN | 1,387 | 25 | 50.0% |
Here are the best places to live in Tennessee
These are the 10 most affordable cities in Tennessee
10 best cities to buy a new house in Tennessee
Check out the 10 safest cities in Tennessee