Frost dates for 58233Forest River, ND
The average last spring frost in Forest River is May 4 and the average first fall frost is October 7, giving a typical growing season of about 156 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 4
- Average first fall frost
- Oct 7
- Growing season
- 156 days
Safer after May 18 (1-in-10 risk)
Possible by Sep 25 (1-in-10 risk)
Last frost typically in 187 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 30 · May 13 · May 26 | Sep 17 · Sep 28 · Oct 10 | 138 days | 100% |
| Frost / freeze (32°F) | Apr 19 · May 4 · May 18 | Sep 25 · Oct 7 · Oct 21 | 156 days | 100% |
| Hard freeze (28°F) | Apr 9 · Apr 24 · May 9 | Oct 3 · Oct 17 · Oct 30 | 174 days | 100% |
Planting calendar for Forest River
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 3 – Jun 9 |
| Tomatoes | Transplant outdoors | May 20 – Jun 17 |
| Peppers | Start seeds indoors | Apr 3 – May 4 |
| Peppers | Transplant outdoors | Jun 3 – Jul 4 |
| Eggplant | Start seeds indoors | Apr 20 – May 19 |
| Eggplant | Transplant outdoors | Jun 3 – Jul 4 |
| Cucumbers | Sow outdoors | Jun 3 – Jun 27 |
| Summer squash | Sow outdoors | May 20 – Jul 4 |
| Winter squash & pumpkins | Sow outdoors | Jun 3 – Jul 4 |
| Snap beans | Sow outdoors | May 20 – Jul 20 |
| Sweet corn | Sow outdoors | May 20 – Jun 17 |
| Watermelon & cantaloupe | Sow outdoors | Jun 3 – Jul 4 |
| Okra | Sow outdoors | May 27 – Jun 19 |
| Peas | Sow outdoors (spring) | Apr 3 – May 19 |
| Potatoes | Plant outdoors (spring) | Apr 3 – Jun 3 |
| Onions | Start seeds indoors (spring) | Feb 20 – Mar 19 |
| Onions | Transplant outdoors (spring) | Apr 20 – May 19 |
| Broccoli | Start seeds indoors (spring) | Mar 16 – Apr 19 |
| Broccoli | Transplant outdoors (spring) | Apr 20 – May 19 |
| Broccoli | Start seeds indoors (fall) | Jun 7 – Jun 17 |
| Broccoli | Transplant outdoors (fall) | Jul 7 – Jul 18 |
| Cabbage | Start seeds indoors (spring) | Mar 6 – Apr 3 |
| Cabbage | Transplant outdoors (spring) | Apr 3 – May 4 |
| Cabbage | Start seeds indoors (fall) | May 28 – Jun 27 |
| Cabbage | Transplant outdoors (fall) | Jun 27 – Jul 28 |
| Leaf lettuce | Sow outdoors (spring) | Apr 3 – Jun 19 |
| Leaf lettuce | Sow outdoors (fall) | Jun 27 – Aug 13 |
| Spinach | Sow outdoors (spring) | Mar 27 – May 10 |
| Spinach | Sow outdoors (fall) | Jul 14 – Aug 18 |
| Radishes | Sow outdoors (spring) | Apr 3 – May 24 |
| Radishes | Sow outdoors (fall) | Jun 27 – Aug 28 |
| Kale | Sow outdoors (spring) | Apr 20 – May 10 |
| Kale | Sow outdoors (fall) | Jun 20 – Jul 28 |
| Carrots | Sow outdoors (spring) | May 4 – Jun 19 |
| Carrots | Sow outdoors (fall) | May 28 – Jul 13 |
| Garlic | Plant outdoors (fall) | Sep 27 – Oct 28 |
Where these dates come from
ZIP code 58233 is matched to the NOAA station Grafton, ND, 21.6 km away, at 827 ft elevation (29 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Grafton, ND (used) | 827 ft | May 4 | Oct 7 |
| Grand Forks Intl Ap, ND | 842 ft | May 16 | Sep 27 |
| Grand Forks Univ (Nws), ND | 830 ft | May 10 | Oct 1 |
| Larimore 4Sw, ND | 1,152 ft | May 11 | Sep 28 |
Frost dates near Forest River
- Minto, ND 58261 · last May 4, first Oct 7
- Gilby, ND 58235 · last May 16, first Sep 27
- Inkster, ND 58244 · last May 4, first Oct 7
- Pisek, ND 58273 · last May 4, first Oct 7
- Grafton, ND 58237 · last May 4, first Oct 7
- Mekinock, ND 58258 · last May 16, first Sep 27
- Manvel, ND 58256 · last May 16, first Sep 27
- Fordville, ND 58231 · last May 11, first Sep 28
Frequently asked questions
- When is the last frost in Forest River, ND?
- For ZIP code 58233, the average last spring frost (32°F) is May 4, based on NOAA 1991-2020 climate normals for the Grafton, ND weather station. There is a 1-in-10 chance of a frost after May 18.
- When is the first frost in Forest River, ND?
- The average first fall frost (32°F) is October 7. 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 58233?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 156 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.