| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 31°F | 51°F | 40°F | 4.1" |
| February | 33°F | 53°F | 42°F | 3.4" |
| March | 41°F | 65°F | 52°F | 5.8" |
| April | 50°F | 74°F | 62°F | 5.8" |
| May | 58°F | 81°F | 69°F | 6.0" |
| June | 67°F | 89°F | 77°F | 4.8" |
| July | 69°F | 91°F | 79°F | 4.2" |
| August | 68°F | 91°F | 79°F | 3.0" |
| September | 61°F | 85°F | 72°F | 3.6" |
| October | 48°F | 74°F | 60°F | 3.5" |
| November | 39°F | 63°F | 50°F | 4.0" |
| December | 34°F | 53°F | 43°F | 5.5" |
| Index | Somerville | Tennessee | National |
| Air quality index | 45 | 76 | 42 |
| Pollution index | 20,539,300 | 2,454,916 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 221 |
| Days with moderate air quality | 139 |
| Days w/ poor A.Q. for sensitive groups | 5 |
| Days with unhealthy air quality | 0 |
| Pollutant | Total |
| Arsenic | 0.060% |
| Benzene | 0.210% |
| Carbon Tetrachloride | 0.060% |
| Lead | 0.170% |
| Mercury | 0.110% |
| City | Population | Air Quality Index | National Avg. |
| Hickory Valley, TN | 86 | 27 | 46.0% |
| Whiteville, TN | 4,482 | 27 | 46.0% |
| Mason, TN | 1,120 | 45 | 10.0% |
| Grand Junction, TN | 388 | 45 | 10.0% |
| Williston, TN | 537 | 45 | 10.0% |
| Somerville, TN | 3,257 | 45 | 10.0% |
| City | Population | Air Quality Index | National Avg. |
| Russell, KY | 3,257 | 42 | 16.0% |
| Thompson-Nicola L (Grasslands), BC | 3,257 | n/a | |
| El Verano, CA | 3,256 | 35 | 30.0% |
| Attica, IN | 3,256 | 42 | 16.0% |
| Berwyn Heights, MD | 3,256 | 47 | 6.0% |
| Somerville, TN | 3,257 | 45 | 10.0% |
Here are the best places to live in Tennessee
These are the 10 cheapest cities in Tennessee
Safest States In The US
Check out the 10 most dangerous cities in Tennessee