Frost dates for 98538Curtis, WA
The average last spring frost in Curtis is April 5 and the average first fall frost is October 25, giving a typical growing season of about 196 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 5
- Average first fall frost
- Oct 25
- Growing season
- 196 days
Safer after May 4 (1-in-10 risk)
Possible by Sep 24 (1-in-10 risk)
Last frost typically in 153 days
Frost risk by date
NOAA reports frost dates as probabilities. The middle date is the average (a 50% chance). For spring, the 10% date is a safer planting date: frost after it happens in about 1 year in 10. Light frost (36°F) can damage tender plants; a hard freeze (28°F) kills most annuals.
| Temperature | Last spring: 90% / 50% / 10% chance | First fall: 10% / 50% / 90% chance | Growing season (50%) | Years with at least one |
|---|---|---|---|---|
| Light frost (36°F) | Apr 6 · May 2 · May 30 | Sep 8 · Oct 2 · Oct 31 | 151 days | 100% |
| Frost / freeze (32°F) | Mar 12 · Apr 5 · May 4 | Sep 24 · Oct 25 · Nov 20 | 196 days | 100% |
| Hard freeze (28°F) | Feb 15 · Mar 10 · Apr 8 | Oct 6 · Nov 9 · Dec 14 | 245 days | 100% |
Planting calendar for Curtis
Planting windows from the University of Maryland Extension calendar, shifted to your average frost dates. Use them as a starting point and adjust for seed packet instructions and local conditions.
| Crop | Task | Window |
|---|---|---|
| Tomatoes | Start seeds indoors | Mar 5 – May 11 |
| Tomatoes | Transplant outdoors | Apr 21 – Jul 5 |
| Peppers | Start seeds indoors | Mar 5 – Apr 5 |
| Peppers | Transplant outdoors | May 5 – Jun 5 |
| Eggplant | Start seeds indoors | Mar 22 – Apr 20 |
| Eggplant | Transplant outdoors | May 5 – Jun 5 |
| Cucumbers | Sow outdoors | May 5 – Jul 15 |
| Summer squash | Sow outdoors | Apr 21 – Jun 5 |
| Winter squash & pumpkins | Sow outdoors | May 5 – Jun 5 |
| Snap beans | Sow outdoors | Apr 21 – Aug 7 |
| Sweet corn | Sow outdoors | Apr 21 – Jul 5 |
| Watermelon & cantaloupe | Sow outdoors | May 5 – Jun 5 |
| Okra | Sow outdoors | Apr 28 – May 21 |
| Peas | Sow outdoors (spring) | Mar 5 – Apr 20 |
| Potatoes | Plant outdoors (spring) | Mar 5 – May 5 |
| Onions | Start seeds indoors (spring) | Jan 22 – Feb 18 |
| Onions | Transplant outdoors (spring) | Mar 22 – Apr 20 |
| Broccoli | Start seeds indoors (spring) | Feb 15 – Mar 21 |
| Broccoli | Transplant outdoors (spring) | Mar 22 – Apr 20 |
| Broccoli | Start seeds indoors (fall) | Jun 25 – Jul 5 |
| Broccoli | Transplant outdoors (fall) | Jul 25 – Aug 5 |
| Cabbage | Start seeds indoors (spring) | Feb 5 – Mar 5 |
| Cabbage | Transplant outdoors (spring) | Mar 5 – Apr 5 |
| Cabbage | Start seeds indoors (fall) | Jun 15 – Jul 15 |
| Cabbage | Transplant outdoors (fall) | Jul 15 – Aug 15 |
| Leaf lettuce | Sow outdoors (spring) | Mar 5 – May 21 |
| Leaf lettuce | Sow outdoors (fall) | Jul 15 – Aug 31 |
| Spinach | Sow outdoors (spring) | Feb 26 – Apr 11 |
| Spinach | Sow outdoors (fall) | Aug 1 – Sep 5 |
| Radishes | Sow outdoors (spring) | Mar 5 – Apr 25 |
| Radishes | Sow outdoors (fall) | Jul 15 – Sep 15 |
| Kale | Sow outdoors (spring) | Mar 22 – Apr 11 |
| Kale | Sow outdoors (fall) | Jul 8 – Aug 15 |
| Carrots | Sow outdoors (spring) | Apr 5 – May 21 |
| Carrots | Sow outdoors (fall) | Jun 15 – Jul 31 |
| Garlic | Plant outdoors (fall) | Oct 15 – Nov 15 |
Where these dates come from
ZIP code 98538 is matched to the NOAA station Toledo Faa Ap, WA, 25.3 km away, at 379 ft elevation (261 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Toledo Faa Ap, WA (used) | 379 ft | Apr 5 | Oct 25 |
| Centralia, WA | 185 ft | Apr 22 | Oct 27 |
| Grays Rvr Hatchery, WA | 100 ft | Apr 27 | Oct 22 |
| Longview, WA | 12 ft | Apr 8 | Nov 5 |
Frost dates near Curtis
- Ryderwood, WA 98581 · last Apr 5, first Oct 25
- Pe Ell, WA 98572 · last Apr 5, first Oct 25
- Adna, WA 98522 · last Apr 22, first Oct 27
- Winlock, WA 98596 · last Apr 5, first Oct 25
- Vader, WA 98593 · last Apr 5, first Oct 25
- Doty, WA 98539 · last Apr 22, first Oct 27
- Napavine, WA 98565 · last Apr 5, first Oct 25
- Chehalis, WA 98532 · last Apr 22, first Oct 27
Frequently asked questions
- When is the last frost in Curtis, WA?
- For ZIP code 98538, the average last spring frost (32°F) is April 5, based on NOAA 1991-2020 climate normals for the Toledo Faa Ap, WA weather station. There is a 1-in-10 chance of a frost after May 4.
- When is the first frost in Curtis, WA?
- The average first fall frost (32°F) is October 25. There is a 1-in-10 chance of frost by September 24, so tender plants are at risk from that point on.
- How long is the growing season in 98538?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 196 days long.
- Are these frost dates a forecast?
- No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.