Frost dates for 49670Northport, MI
The average last spring frost in Northport is May 9 and the average first fall frost is October 26, giving a typical growing season of about 169 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 9
- Average first fall frost
- Oct 26
- Growing season
- 169 days
Safer after May 24 (1-in-10 risk)
Possible by Oct 11 (1-in-10 risk)
Last frost typically in 189 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 8 · May 23 · Jun 5 | Sep 26 · Oct 10 · Oct 25 | 140 days | 100% |
| Frost / freeze (32°F) | Apr 24 · May 9 · May 24 | Oct 11 · Oct 26 · Nov 10 | 169 days | 100% |
| Hard freeze (28°F) | Apr 12 · Apr 27 · May 12 | Oct 25 · Nov 8 · Nov 23 | 194 days | 100% |
Planting calendar for Northport
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 – Jul 6 |
| 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 – Jul 16 |
| Summer squash | Sow outdoors | May 25 – Jul 9 |
| Winter squash & pumpkins | Sow outdoors | Jun 8 – Jul 9 |
| Snap beans | Sow outdoors | May 25 – Aug 8 |
| Sweet corn | Sow outdoors | May 25 – Jul 6 |
| 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 26 – Jul 6 |
| Broccoli | Transplant outdoors (fall) | Jul 26 – Aug 6 |
| Cabbage | Start seeds indoors (spring) | Mar 11 – Apr 8 |
| Cabbage | Transplant outdoors (spring) | Apr 8 – May 9 |
| Cabbage | Start seeds indoors (fall) | Jun 16 – Jul 16 |
| Cabbage | Transplant outdoors (fall) | Jul 16 – Aug 16 |
| Leaf lettuce | Sow outdoors (spring) | Apr 8 – Jun 24 |
| Leaf lettuce | Sow outdoors (fall) | Jul 16 – Sep 1 |
| Spinach | Sow outdoors (spring) | Apr 1 – May 15 |
| Spinach | Sow outdoors (fall) | Aug 2 – Sep 6 |
| Radishes | Sow outdoors (spring) | Apr 8 – May 29 |
| Radishes | Sow outdoors (fall) | Jul 16 – Sep 16 |
| Kale | Sow outdoors (spring) | Apr 25 – May 15 |
| Kale | Sow outdoors (fall) | Jul 9 – Aug 16 |
| Carrots | Sow outdoors (spring) | May 9 – Jun 24 |
| Carrots | Sow outdoors (fall) | Jun 16 – Aug 1 |
| Garlic | Plant outdoors (fall) | Oct 16 – Nov 16 |
Where these dates come from
ZIP code 49670 is matched to the NOAA station Northport 2W, MI, 3 km away, at 746 ft elevation (5 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Northport 2W, MI (used) | 746 ft | May 9 | Oct 26 |
| Old Mission 3Ssw, MI | 656 ft | May 13 | Oct 19 |
| Nw Michigan Rsch Farm, MI | 820 ft | Apr 30 | Nov 1 |
| Maple City 1E, MI | 799 ft | May 22 | Oct 9 |
Frost dates near Northport
- Omena, MI 49674 · last May 9, first Oct 26
- Suttons Bay, MI 49682 · last Apr 30, first Nov 1
- Lake Leelanau, MI 49653 · last Apr 30, first Nov 1
- Old Mission, MI 49673 · last May 13, first Oct 19
- Eastport, MI 49627 · last May 23, first Oct 2
- Kewadin, MI 49648 · last May 9, first Oct 26
- Central Lake, MI 49622 · last May 23, first Oct 2
- Ellsworth, MI 49729 · last May 23, first Oct 2
Frequently asked questions
- When is the last frost in Northport, MI?
- For ZIP code 49670, the average last spring frost (32°F) is May 9, based on NOAA 1991-2020 climate normals for the Northport 2W, MI weather station. There is a 1-in-10 chance of a frost after May 24.
- When is the first frost in Northport, MI?
- The average first fall frost (32°F) is October 26. There is a 1-in-10 chance of frost by October 11, so tender plants are at risk from that point on.
- How long is the growing season in 49670?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 169 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.