Frost dates for 83811Clark Fork, ID
The average last spring frost in Clark Fork is May 9 and the average first fall frost is October 8, giving a typical growing season of about 153 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 9
- Average first fall frost
- Oct 8
- Growing season
- 153 days
Safer after May 25 (1-in-10 risk)
Possible by Sep 25 (1-in-10 risk)
Last frost typically in 188 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 12 · May 28 · Jun 14 | Sep 6 · Sep 23 · Oct 6 | 116 days | 100% |
| Frost / freeze (32°F) | Apr 24 · May 9 · May 25 | Sep 25 · Oct 8 · Oct 26 | 153 days | 100% |
| Hard freeze (28°F) | Mar 31 · Apr 22 · May 9 | Oct 5 · Oct 25 · Nov 13 | 187 days | 100% |
Planting calendar for Clark Fork
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 8 – Jun 14 |
| Tomatoes | Transplant outdoors | May 25 – Jun 18 |
| Peppers | Start seeds indoors | Apr 8 – May 9 |
| Peppers | Transplant outdoors | Jun 8 – Jul 9 |
| Eggplant | Start seeds indoors | Apr 25 – May 24 |
| Eggplant | Transplant outdoors | Jun 8 – Jul 9 |
| Cucumbers | Sow outdoors | Jun 8 – Jun 28 |
| Summer squash | Sow outdoors | May 25 – Jul 9 |
| Winter squash & pumpkins | Sow outdoors | Jun 8 – Jul 9 |
| Snap beans | Sow outdoors | May 25 – Jul 21 |
| Sweet corn | Sow outdoors | May 25 – Jun 18 |
| Watermelon & cantaloupe | Sow outdoors | Jun 8 – Jul 9 |
| Okra | Sow outdoors | Jun 1 – Jun 24 |
| Peas | Sow outdoors (spring) | Apr 8 – May 24 |
| Potatoes | Plant outdoors (spring) | Apr 8 – Jun 8 |
| Onions | Start seeds indoors (spring) | Feb 25 – Mar 24 |
| Onions | Transplant outdoors (spring) | Apr 25 – May 24 |
| Broccoli | Start seeds indoors (spring) | Mar 21 – Apr 24 |
| Broccoli | Transplant outdoors (spring) | Apr 25 – May 24 |
| Broccoli | Start seeds indoors (fall) | Jun 8 – Jun 18 |
| Broccoli | Transplant outdoors (fall) | Jul 8 – Jul 19 |
| Cabbage | Start seeds indoors (spring) | Mar 11 – Apr 8 |
| Cabbage | Transplant outdoors (spring) | Apr 8 – May 9 |
| Cabbage | Start seeds indoors (fall) | May 29 – Jun 28 |
| Cabbage | Transplant outdoors (fall) | Jun 28 – Jul 29 |
| Leaf lettuce | Sow outdoors (spring) | Apr 8 – Jun 24 |
| Leaf lettuce | Sow outdoors (fall) | Jun 28 – Aug 14 |
| Spinach | Sow outdoors (spring) | Apr 1 – May 15 |
| Spinach | Sow outdoors (fall) | Jul 15 – Aug 19 |
| Radishes | Sow outdoors (spring) | Apr 8 – May 29 |
| Radishes | Sow outdoors (fall) | Jun 28 – Aug 29 |
| Kale | Sow outdoors (spring) | Apr 25 – May 15 |
| Kale | Sow outdoors (fall) | Jun 21 – Jul 29 |
| Carrots | Sow outdoors (spring) | May 9 – Jun 24 |
| Carrots | Sow outdoors (fall) | May 29 – Jul 14 |
| Garlic | Plant outdoors (fall) | Sep 28 – Oct 29 |
Where these dates come from
ZIP code 83811 is matched to the NOAA station Cabinet Gorge, ID, 10.3 km away, at 2,173 ft elevation (55 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Cabinet Gorge, ID (used) | 2,173 ft | May 9 | Oct 8 |
| Heron 2 Nw, MT | 2,240 ft | May 20 | Sep 20 |
| Sandpoint Exp Stn, ID | 2,126 ft | May 8 | Sep 28 |
| Bayview Model Basin, ID | 2,087 ft | May 22 | Sep 22 |
Frost dates near Clark Fork
- Hope, ID 83836 · last May 8, first Sep 28
- Heron, MT 59844 · last May 20, first Sep 20
- Noxon, MT 59853 · last —, first —
- Sagle, ID 83860 · last May 8, first Sep 28
- Kootenai, ID 83840 · last May 8, first Sep 28
- Ponderay, ID 83852 · last May 8, first Sep 28
- Sandpoint, ID 83864 · last May 8, first Sep 28
- Careywood, ID 83809 · last May 22, first Sep 22
Frequently asked questions
- When is the last frost in Clark Fork, ID?
- For ZIP code 83811, the average last spring frost (32°F) is May 9, based on NOAA 1991-2020 climate normals for the Cabinet Gorge, ID weather station. There is a 1-in-10 chance of a frost after May 25.
- When is the first frost in Clark Fork, ID?
- The average first fall frost (32°F) is October 8. There is a 1-in-10 chance of frost by September 25, so tender plants are at risk from that point on.
- How long is the growing season in 83811?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 153 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.