| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 13°F | 39°F | 25°F | 0.6" |
| February | 16°F | 43°F | 29°F | 0.8" |
| March | 28°F | 58°F | 42°F | 1.3" |
| April | 39°F | 68°F | 53°F | 3.3" |
| May | 49°F | 78°F | 63°F | 5.7" |
| June | 61°F | 88°F | 74°F | 5.4" |
| July | 65°F | 92°F | 78°F | 3.1" |
| August | 62°F | 89°F | 75°F | 4.4" |
| September | 53°F | 83°F | 67°F | 4.6" |
| October | 40°F | 70°F | 54°F | 3.2" |
| November | 28°F | 57°F | 41°F | 1.0" |
| December | 16°F | 41°F | 27°F | 1.5" |
| Index | Roca | Nebraska | National |
| Air quality index | 31 | 86 | 50 |
| Pollution index | 648,221 | 701,730 | 5,066,862 |
| Measurement | Total |
| Days measured | 360 |
| Days with good air quality | 338 |
| Days with moderate air quality | 22 |
| 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 | 0.002% |
| Mercury | 0.000% |
| City, State | Population | Air Quality Index | National Avg. |
| Cortland, NE | 547 | 31 | 38% |
| Douglas, NE | 215 | 31 | 38% |
| Alvo, NE | 132 | 31 | 38% |
| Palmyra, NE | 659 | 31 | 38% |
| Yankee Hill, NE | 378 | 31 | 38% |
| Roca, NE | 195 | 31 | 38% |
| City, State | Population | Air Quality Index | National Avg. |
| Norwood, GA | 195 | 47 | 6% |
| Maple City, MI | 195 | 36 | 28% |
| Denning, AR | 195 | 36 | 28% |
| Argonne, WI | 195 | 34 | 32% |
| Harrison, ID | 195 | 43 | 14% |
| Roca, NE | 195 | 31 | 38% |
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