Frost dates for 98610Carson, WA
The average last spring frost in Carson is April 20 and the average first fall frost is October 13, giving a typical growing season of about 177 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 20
- Average first fall frost
- Oct 13
- Growing season
- 177 days
Safer after May 9 (1-in-10 risk)
Possible by Sep 30 (1-in-10 risk)
Last frost typically in 169 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 23 · May 7 · May 25 | Sep 15 · Oct 1 · Oct 16 | 146 days | 100% |
| Frost / freeze (32°F) | Mar 29 · Apr 20 · May 9 | Sep 30 · Oct 13 · Nov 1 | 177 days | 100% |
| Hard freeze (28°F) | Feb 28 · Mar 20 · Apr 10 | Oct 8 · Oct 28 · Nov 21 | 223 days | 100% |
Planting calendar for Carson
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 20 – May 26 |
| Tomatoes | Transplant outdoors | May 6 – Jun 23 |
| Peppers | Start seeds indoors | Mar 20 – Apr 20 |
| Peppers | Transplant outdoors | May 20 – Jun 20 |
| Eggplant | Start seeds indoors | Apr 6 – May 5 |
| Eggplant | Transplant outdoors | May 20 – Jun 20 |
| Cucumbers | Sow outdoors | May 20 – Jul 3 |
| Summer squash | Sow outdoors | May 6 – Jun 20 |
| Winter squash & pumpkins | Sow outdoors | May 20 – Jun 20 |
| Snap beans | Sow outdoors | May 6 – Jul 26 |
| Sweet corn | Sow outdoors | May 6 – Jun 23 |
| Watermelon & cantaloupe | Sow outdoors | May 20 – Jun 20 |
| Okra | Sow outdoors | May 13 – Jun 5 |
| Peas | Sow outdoors (spring) | Mar 20 – May 5 |
| Potatoes | Plant outdoors (spring) | Mar 20 – May 20 |
| Onions | Start seeds indoors (spring) | Feb 6 – Mar 5 |
| Onions | Transplant outdoors (spring) | Apr 6 – May 5 |
| Broccoli | Start seeds indoors (spring) | Mar 2 – Apr 5 |
| Broccoli | Transplant outdoors (spring) | Apr 6 – May 5 |
| Broccoli | Start seeds indoors (fall) | Jun 13 – Jun 23 |
| Broccoli | Transplant outdoors (fall) | Jul 13 – Jul 24 |
| Cabbage | Start seeds indoors (spring) | Feb 20 – Mar 20 |
| Cabbage | Transplant outdoors (spring) | Mar 20 – Apr 20 |
| Cabbage | Start seeds indoors (fall) | Jun 3 – Jul 3 |
| Cabbage | Transplant outdoors (fall) | Jul 3 – Aug 3 |
| Leaf lettuce | Sow outdoors (spring) | Mar 20 – Jun 5 |
| Leaf lettuce | Sow outdoors (fall) | Jul 3 – Aug 19 |
| Spinach | Sow outdoors (spring) | Mar 13 – Apr 26 |
| Spinach | Sow outdoors (fall) | Jul 20 – Aug 24 |
| Radishes | Sow outdoors (spring) | Mar 20 – May 10 |
| Radishes | Sow outdoors (fall) | Jul 3 – Sep 3 |
| Kale | Sow outdoors (spring) | Apr 6 – Apr 26 |
| Kale | Sow outdoors (fall) | Jun 26 – Aug 3 |
| Carrots | Sow outdoors (spring) | Apr 20 – Jun 5 |
| Carrots | Sow outdoors (fall) | Jun 3 – Jul 19 |
| Garlic | Plant outdoors (fall) | Oct 3 – Nov 3 |
Where these dates come from
ZIP code 98610 is matched to the NOAA station Hood Rvr Exp Stn, OR, 25.7 km away, at 500 ft elevation (97 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Hood Rvr Exp Stn, OR (used) | 500 ft | Apr 20 | Oct 13 |
| Cascade Locks, OR | 142 ft | Mar 24 | Nov 20 |
| Bonneville Dam, OR | 62 ft | Mar 14 | Nov 27 |
| Carson Fish Hatchery, WA | 1,134 ft | May 2 | Oct 9 |
Frost dates near Carson
- Stevenson, WA 98648 · last Mar 14, first Nov 27
- Cascade Locks, OR 97014 · last Mar 14, first Nov 27
- Bingen, WA 98605 · last May 2, first Oct 9
- North Bonneville, WA 98639 · last Mar 14, first Nov 27
- Underwood, WA 98651 · last May 13, first Oct 3
- Hood River, OR 97031 · last Apr 20, first Oct 13
- Odell, OR 97044 · last Apr 20, first Oct 13
- White Salmon, WA 98672 · last Apr 20, first Oct 13
Frequently asked questions
- When is the last frost in Carson, WA?
- For ZIP code 98610, the average last spring frost (32°F) is April 20, based on NOAA 1991-2020 climate normals for the Hood Rvr Exp Stn, OR weather station. There is a 1-in-10 chance of a frost after May 9.
- When is the first frost in Carson, WA?
- The average first fall frost (32°F) is October 13. There is a 1-in-10 chance of frost by September 30, so tender plants are at risk from that point on.
- How long is the growing season in 98610?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 177 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.