| Month | Temp. (min) | Temp. (max) | Temp. (avg) | Precipitation |
| January | 9°F | 24°F | 16°F | 1.2" |
| February | 11°F | 28°F | 18°F | 2.3" |
| March | 27°F | 44°F | 34°F | 2.2" |
| April | 39°F | 59°F | 47°F | 2.9" |
| May | 50°F | 71°F | 59°F | 4.0" |
| June | 60°F | 80°F | 69°F | 5.5" |
| July | 64°F | 83°F | 73°F | 6.8" |
| August | 61°F | 80°F | 70°F | 6.7" |
| September | 53°F | 74°F | 63°F | 4.4" |
| October | 41°F | 60°F | 49°F | 3.0" |
| November | 28°F | 45°F | 36°F | 2.0" |
| December | 13°F | 28°F | 20°F | 1.4" |
| Index | Lake Crystal | Minnesota | National |
| Air quality index | 46 | 35 | 42 |
| Pollution index | 2,548,510 | 1,854,519 | 2,726,193 |
| Measurement | Total |
| Days measured | 365 |
| Days with good air quality | 214 |
| Days with moderate air quality | 148 |
| Days w/ poor A.Q. for sensitive groups | 2 |
| Days with unhealthy air quality | 1 |
| Pollutant | Total |
| Arsenic | 0.010% |
| Benzene | 0.050% |
| Carbon Tetrachloride | 0.020% |
| Lead | 0.330% |
| Mercury | 0.490% |
| City | Population | Air Quality Index | National Avg. |
| Good Thunder, MN | 569 | 15 | 70.0% |
| Mapleton, MN | 1,650 | 15 | 70.0% |
| Vernon Center, MN | 364 | 15 | 70.0% |
| Amboy, MN | 627 | 15 | 70.0% |
| Searles, MN | 294 | 32 | 36.0% |
| Lake Crystal, MN | 2,587 | 46 | 8.0% |
| City | Population | Air Quality Index | National Avg. |
| Drum Point, MD | 2,587 | 41 | 18.0% |
| Carthage, NC | 2,587 | 29 | 42.0% |
| Beaver Dam Lake, NY | 2,587 | 36 | 28.0% |
| Kalona, IA | 2,588 | 35 | 30.0% |
| Janesville, MN | 2,588 | 36 | 28.0% |
| Lake Crystal, MN | 2,587 | 46 | 8.0% |