| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 13°F | 32°F | 22°F | 1.0" |
| February | 15°F | 36°F | 24°F | 1.3" |
| March | 28°F | 52°F | 38°F | 2.8" |
| April | 37°F | 63°F | 49°F | 4.9" |
| May | 48°F | 74°F | 60°F | 6.1" |
| June | 59°F | 83°F | 71°F | 6.4" |
| July | 63°F | 87°F | 74°F | 4.8" |
| August | 60°F | 83°F | 71°F | 8.2" |
| September | 51°F | 78°F | 63°F | 5.4" |
| October | 39°F | 65°F | 50°F | 6.4" |
| November | 27°F | 51°F | 37°F | 2.7" |
| December | 15°F | 34°F | 24°F | 2.3" |
| Index | Newcastle | Nebraska | National |
| Air quality index | 35 | 86 | 42 |
| Pollution index | 397,267 | 590,627 | 2,726,193 |
| Measurement | Total |
| Days measured | 364 |
| Days with good air quality | 322 |
| Days with moderate air quality | 42 |
| 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 | 0.001% |
| Lead | 0.000% |
| Mercury | 0.000% |
| City | Population | Air Quality Index | National Avg. |
| Wynot, NE | 252 | 35 | 30.0% |
| Elk Point, SD | 2,102 | 35 | 30.0% |
| Westfield, IA | 120 | 35 | 30.0% |
| Martinsburg, NE | 70 | 35 | 30.0% |
| Richland, SD | 154 | 35 | 30.0% |
| Newcastle, NE | 407 | 35 | 30.0% |
| City | Population | Air Quality Index | National Avg. |
| Nutrioso, AZ | 407 | 44 | 12.0% |
| Bangor, CA | 407 | 44 | 12.0% |
| Dorrington, CA | 407 | 39 | 22.0% |
| Point Arena, CA | 407 | 33 | 34.0% |
| Walton, NE | 407 | 31 | 38.0% |
| Newcastle, NE | 407 | 35 | 30.0% |
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