Frost dates for 49690Williamsburg, MI
The average last spring frost in Williamsburg is May 12 and the average first fall frost is October 16, giving a typical growing season of about 155 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 12
- Average first fall frost
- Oct 16
- Growing season
- 155 days
Safer after May 27 (1-in-10 risk)
Possible by Oct 1 (1-in-10 risk)
Last frost typically in 191 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 9 · May 25 · Jun 5 | Sep 19 · Oct 2 · Oct 16 | 130 days | 100% |
| Frost / freeze (32°F) | Apr 26 · May 12 · May 27 | Oct 1 · Oct 16 · Nov 1 | 155 days | 100% |
| Hard freeze (28°F) | Apr 15 · Apr 30 · May 16 | Oct 12 · Oct 30 · Nov 13 | 182 days | 100% |
Planting calendar for Williamsburg
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 11 – Jun 17 |
| Tomatoes | Transplant outdoors | May 28 – Jun 26 |
| Peppers | Start seeds indoors | Apr 11 – May 12 |
| Peppers | Transplant outdoors | Jun 11 – Jul 12 |
| Eggplant | Start seeds indoors | Apr 28 – May 27 |
| Eggplant | Transplant outdoors | Jun 11 – Jul 12 |
| Cucumbers | Sow outdoors | Jun 11 – Jul 6 |
| Summer squash | Sow outdoors | May 28 – Jul 12 |
| Winter squash & pumpkins | Sow outdoors | Jun 11 – Jul 12 |
| Snap beans | Sow outdoors | May 28 – Jul 29 |
| Sweet corn | Sow outdoors | May 28 – Jun 26 |
| Watermelon & cantaloupe | Sow outdoors | Jun 11 – Jul 12 |
| Okra | Sow outdoors | Jun 4 – Jun 27 |
| Peas | Sow outdoors (spring) | Apr 11 – May 27 |
| Potatoes | Plant outdoors (spring) | Apr 11 – Jun 11 |
| Onions | Start seeds indoors (spring) | Feb 28 – Mar 27 |
| Onions | Transplant outdoors (spring) | Apr 28 – May 27 |
| Broccoli | Start seeds indoors (spring) | Mar 24 – Apr 27 |
| Broccoli | Transplant outdoors (spring) | Apr 28 – May 27 |
| Broccoli | Start seeds indoors (fall) | Jun 16 – Jun 26 |
| Broccoli | Transplant outdoors (fall) | Jul 16 – Jul 27 |
| Cabbage | Start seeds indoors (spring) | Mar 14 – Apr 11 |
| Cabbage | Transplant outdoors (spring) | Apr 11 – May 12 |
| Cabbage | Start seeds indoors (fall) | Jun 6 – Jul 6 |
| Cabbage | Transplant outdoors (fall) | Jul 6 – Aug 6 |
| Leaf lettuce | Sow outdoors (spring) | Apr 11 – Jun 27 |
| Leaf lettuce | Sow outdoors (fall) | Jul 6 – Aug 22 |
| Spinach | Sow outdoors (spring) | Apr 4 – May 18 |
| Spinach | Sow outdoors (fall) | Jul 23 – Aug 27 |
| Radishes | Sow outdoors (spring) | Apr 11 – Jun 1 |
| Radishes | Sow outdoors (fall) | Jul 6 – Sep 6 |
| Kale | Sow outdoors (spring) | Apr 28 – May 18 |
| Kale | Sow outdoors (fall) | Jun 29 – Aug 6 |
| Carrots | Sow outdoors (spring) | May 12 – Jun 27 |
| Carrots | Sow outdoors (fall) | Jun 6 – Jul 22 |
| Garlic | Plant outdoors (fall) | Oct 6 – Nov 6 |
Where these dates come from
ZIP code 49690 is matched to the NOAA station Traverse City Cherry Cptl Ap, MI, 13.5 km away, at 618 ft elevation (127 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Traverse City Cherry Cptl Ap, MI (used) | 618 ft | May 12 | Oct 16 |
| Old Mission 3Ssw, MI | 656 ft | May 13 | Oct 19 |
| Traverse City Munson, MI | 635 ft | May 9 | Oct 15 |
| S Boardman 2W, MI | 1,046 ft | May 24 | Oct 4 |
Frost dates near Williamsburg
- Acme, MI 49610 · last May 12, first Oct 16
- Elk Rapids, MI 49629 · last May 12, first Oct 16
- Traverse City, MI 49685 · last May 9, first Oct 15
- Rapid City, MI 49676 · last May 12, first Oct 16
- Old Mission, MI 49673 · last May 13, first Oct 19
- Alden, MI 49612 · last May 24, first Oct 1
- Mayfield, MI 49666 · last May 12, first Oct 16
- South Boardman, MI 49680 · last May 24, first Oct 1
Frequently asked questions
- When is the last frost in Williamsburg, MI?
- For ZIP code 49690, the average last spring frost (32°F) is May 12, based on NOAA 1991-2020 climate normals for the Traverse City Cherry Cptl Ap, MI weather station. There is a 1-in-10 chance of a frost after May 27.
- When is the first frost in Williamsburg, MI?
- The average first fall frost (32°F) is October 16. There is a 1-in-10 chance of frost by October 1, so tender plants are at risk from that point on.
- How long is the growing season in 49690?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 155 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.