Tampico, Washington has a Humid Continental Climate - Dry Cool Summer climate (Köppen classification: Dsb). Average annual temperatures range from 35.8 °F (low) to 59.1 °F (high). Annual precipitation averages 13.7 Inches. Tampico is located in USDA Plant Hardiness Zone 7a. The growing season typically runs from the last frost around May 1 - May 10 through the first frost around Sep. 21 - Sep. 30.
| Month | Avg. Low | Avg. High | Avg. Precip |
|---|---|---|---|
| January | 23.1 °F | 36.4 °F | 2.41 in. |
| February | 25.2 °F | 42.5 °F | 1.59 in. |
| March | 29.2 °F | 50.1 °F | 1.29 in. |
| April | 34.0 °F | 57.8 °F | 0.83 in. |
| May | 40.4 °F | 67.3 °F | 0.99 in. |
| June | 46.0 °F | 73.9 °F | 0.68 in. |
| July | 51.8 °F | 83.5 °F | 0.36 in. |
| August | 51.0 °F | 82.9 °F | 0.27 in. |
| September | 44.2 °F | 74.2 °F | 0.34 in. |
| October | 35.2 °F | 59.9 °F | 1.16 in. |
| November | 27.6 °F | 45.1 °F | 1.4 in. |
| December | 22.2 °F | 35.2 °F | 2.35 in. |
| Annual | 35.8 °F | 59.1 °F | 13.67 in. |
| Average First Frost Date | Sep. 21 - Sep. 30 |
| Average Last Frost Date | May 1 - May 10 |
| Average Days With Frost | 150-180 Days |
| Plant Hardiness Zone | Zone 7a : 0°F to 5°F |
| Plant Hardiness Zone - 2012 | Zone 6b : -5°F to 0°F |
| Current Drought Conditions | Moderate Drought |
| Köppen Climate Classification | Dsb - Humid Continental Climate - Dry Cool Summer |