The last 36°F Spring frost date is 30% likely to be on Apr 30. (See detailed probabilities below.)
The last 32°F light freeze date is 30% likely to be on Apr 13. (See detailed probabilities below.)
(See also 🍂 First Fall Frost Dates.)
Last frost date probabilities for Rock Island, WA are based on historical climate data.
Always check your local forecast for the most up-to-date frost warnings.
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The last spring frost signals when your area is safe from freezing temperatures. Tender plants can now grow outdoors without cold damage! This marks the beginning of the growing season. Last spring frost serves as your essential starting point for planting warm-season crops. It's also time to remove winter protection from your perennials. Enjoy the longer days and warmer weather!
Start seeds indoors several weeks before your last frost date. This gives plants time to reach transplanting size when weather permits. Plan your outdoor planting schedule around your area's average last frost date. Plant some crops before and some after this date to protect against weather changes. Look for spots in your yard where frost stays longer or disappears earlier. Create your own frost map to use all available growing space and extend your season. Keep watching your local weather forecast to catch any surprise late frosts.
| Probability of frost (36°F) on or after… | |
|---|---|
| 10% chance | May 9 |
| 20% chance | May 4 |
| 30% chance | Apr 30 |
| 40% chance | Apr 28 |
| 50% chance | Apr 25 |
| 60% chance | Apr 22 |
| 70% chance | Apr 20 |
| 80% chance | Apr 16 |
| 90% chance | Apr 9 |
| Probability of light freeze (32°F) on or after… | |
|---|---|
| 10% chance | Apr 23 |
| 20% chance | Apr 17 |
| 30% chance | Apr 13 |
| 40% chance | Apr 9 |
| 50% chance | Apr 5 |
| 60% chance | Apr 1 |
| 70% chance | Mar 30 |
| 80% chance | Mar 25 |
| 90% chance | Mar 17 |
| Probability of moderate freeze (28°F) on or after… | |
|---|---|
| 10% chance | Apr 4 |
| 20% chance | Mar 30 |
| 30% chance | Mar 24 |
| 40% chance | Mar 19 |
| 50% chance | Mar 14 |
| 60% chance | Mar 10 |
| 70% chance | Mar 6 |
| 80% chance | Mar 2 |
| 90% chance | Feb 24 |
| Probability of moderate hard freeze (24°F) on or after… | |
|---|---|
| 10% chance | Mar 16 |
| 20% chance | Mar 9 |
| 30% chance | Mar 4 |
| 40% chance | Mar 1 |
| 50% chance | Feb 26 |
| 60% chance | Feb 22 |
| 70% chance | Feb 18 |
| 80% chance | Feb 13 |
| 90% chance | Feb 6 |
| Probability of hard freeze (20°F) on or after… | |
|---|---|
| 10% chance | Mar 4 |
| 20% chance | Feb 27 |
| 30% chance | Feb 22 |
| 40% chance | Feb 17 |
| 50% chance | Feb 13 |
| 60% chance | Feb 9 |
| 70% chance | Feb 5 |
| 80% chance | Jan 31 |
| 90% chance | Jan 21 |
| Probability of severe hard freeze (16°F) on or after… | |
|---|---|
| 10% chance | Feb 25 |
| 20% chance | Feb 18 |
| 30% chance | Feb 13 |
| 40% chance | Feb 8 |
| 50% chance | Feb 3 |
| 60% chance | Jan 31 |
| 70% chance | Jan 23 |
| 80% chance | Jan 16 |
| 90% chance | Jan 7 |
Agricultural climatic data from weather station: WENATCHEE PANGBORN AP (USW00094239)