Frost dates for 99360Touchet, WA
The average last spring frost in Touchet is May 2 and the average first fall frost is October 1, giving a typical growing season of about 151 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 2
- Average first fall frost
- Oct 1
- Growing season
- 151 days
Safer after May 18 (1-in-10 risk)
Possible by Sep 14 (1-in-10 risk)
Last frost typically in 181 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) | May 3 · May 18 · Jun 7 | Sep 1 · Sep 17 · Oct 2 | 121 days | 100% |
| Frost / freeze (32°F) | Apr 16 · May 2 · May 18 | Sep 14 · Oct 1 · Oct 16 | 151 days | 100% |
| Hard freeze (28°F) | Mar 23 · Apr 15 · May 1 | Sep 28 · Oct 12 · Oct 30 | 181 days | 100% |
Planting calendar for Touchet
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 | Apr 1 – Jun 7 |
| Tomatoes | Transplant outdoors | May 18 – Jun 11 |
| Peppers | Start seeds indoors | Apr 1 – May 2 |
| Peppers | Transplant outdoors | Jun 1 – Jul 2 |
| Eggplant | Start seeds indoors | Apr 18 – May 17 |
| Eggplant | Transplant outdoors | Jun 1 – Jul 2 |
| Cucumbers | Sow outdoors | Jun 1 – Jun 21 |
| Summer squash | Sow outdoors | May 18 – Jul 2 |
| Winter squash & pumpkins | Sow outdoors | Jun 1 – Jul 2 |
| Snap beans | Sow outdoors | May 18 – Jul 14 |
| Sweet corn | Sow outdoors | May 18 – Jun 11 |
| Watermelon & cantaloupe | Sow outdoors | Jun 1 – Jul 2 |
| Okra | Sow outdoors | May 25 – Jun 17 |
| Peas | Sow outdoors (spring) | Apr 1 – May 17 |
| Potatoes | Plant outdoors (spring) | Apr 1 – Jun 1 |
| Onions | Start seeds indoors (spring) | Feb 18 – Mar 17 |
| Onions | Transplant outdoors (spring) | Apr 18 – May 17 |
| Broccoli | Start seeds indoors (spring) | Mar 14 – Apr 17 |
| Broccoli | Transplant outdoors (spring) | Apr 18 – May 17 |
| Broccoli | Start seeds indoors (fall) | Jun 1 – Jun 11 |
| Broccoli | Transplant outdoors (fall) | Jul 1 – Jul 12 |
| Cabbage | Start seeds indoors (spring) | Mar 4 – Apr 1 |
| Cabbage | Transplant outdoors (spring) | Apr 1 – May 2 |
| Cabbage | Start seeds indoors (fall) | May 22 – Jun 21 |
| Cabbage | Transplant outdoors (fall) | Jun 21 – Jul 22 |
| Leaf lettuce | Sow outdoors (spring) | Apr 1 – Jun 17 |
| Leaf lettuce | Sow outdoors (fall) | Jun 21 – Aug 7 |
| Spinach | Sow outdoors (spring) | Mar 25 – May 8 |
| Spinach | Sow outdoors (fall) | Jul 8 – Aug 12 |
| Radishes | Sow outdoors (spring) | Apr 1 – May 22 |
| Radishes | Sow outdoors (fall) | Jun 21 – Aug 22 |
| Kale | Sow outdoors (spring) | Apr 18 – May 8 |
| Kale | Sow outdoors (fall) | Jun 14 – Jul 22 |
| Carrots | Sow outdoors (spring) | May 2 – Jun 17 |
| Carrots | Sow outdoors (fall) | May 22 – Jul 7 |
| Garlic | Plant outdoors (fall) | Sep 21 – Oct 22 |
Where these dates come from
ZIP code 99360 is matched to the NOAA station Whitman Mission, WA, 16.3 km away, at 632 ft elevation (136 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Whitman Mission, WA (used) | 632 ft | May 2 | Oct 1 |
| Ice Harbor Dam, WA | 368 ft | Apr 7 | Oct 22 |
| Milton Freewater, OR | 970 ft | Mar 25 | Oct 29 |
| Walla Walla Rgnl Ap, WA | 1,166 ft | Mar 27 | Oct 31 |
Frost dates near Touchet
- Wallula, WA 99363 · last Apr 7, first Oct 22
- College Place, WA 99324 · last May 2, first Oct 1
- Burbank, WA 99323 · last Apr 7, first Oct 22
- Helix, OR 97835 · last May 12, first Sep 27
- Walla Walla, WA 99362 · last Mar 27, first Oct 31
- Milton Freewater, OR 97862 · last Mar 25, first Oct 29
- Athena, OR 97813 · last May 12, first Sep 27
- Prescott, WA 99348 · last Apr 28, first Oct 13
Frequently asked questions
- When is the last frost in Touchet, WA?
- For ZIP code 99360, the average last spring frost (32°F) is May 2, based on NOAA 1991-2020 climate normals for the Whitman Mission, WA weather station. There is a 1-in-10 chance of a frost after May 18.
- When is the first frost in Touchet, WA?
- The average first fall frost (32°F) is October 1. There is a 1-in-10 chance of frost by September 14, so tender plants are at risk from that point on.
- How long is the growing season in 99360?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 151 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.