Frost dates for 48707Bay City, MI
The average last spring frost in Bay City is May 3 and the average first fall frost is October 14, giving a typical growing season of about 161 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 3
- Average first fall frost
- Oct 14
- Growing season
- 161 days
Safer after May 23 (1-in-10 risk)
Possible by Sep 29 (1-in-10 risk)
Last frost typically in 182 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 16 · May 31 | Sep 16 · Sep 30 · Oct 14 | 136 days | 100% |
| Frost / freeze (32°F) | Apr 20 · May 3 · May 23 | Sep 29 · Oct 14 · Oct 30 | 161 days | 100% |
| Hard freeze (28°F) | Apr 8 · Apr 23 · May 10 | Oct 12 · Oct 29 · Nov 10 | 188 days | 100% |
Planting calendar for Bay City
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 2 – Jun 8 |
| Tomatoes | Transplant outdoors | May 19 – Jun 24 |
| Peppers | Start seeds indoors | Apr 2 – May 3 |
| Peppers | Transplant outdoors | Jun 2 – Jul 3 |
| Eggplant | Start seeds indoors | Apr 19 – May 18 |
| Eggplant | Transplant outdoors | Jun 2 – Jul 3 |
| Cucumbers | Sow outdoors | Jun 2 – Jul 4 |
| Summer squash | Sow outdoors | May 19 – Jul 3 |
| Winter squash & pumpkins | Sow outdoors | Jun 2 – Jul 3 |
| Snap beans | Sow outdoors | May 19 – Jul 27 |
| Sweet corn | Sow outdoors | May 19 – Jun 24 |
| Watermelon & cantaloupe | Sow outdoors | Jun 2 – Jul 3 |
| Okra | Sow outdoors | May 26 – Jun 18 |
| Peas | Sow outdoors (spring) | Apr 2 – May 18 |
| Potatoes | Plant outdoors (spring) | Apr 2 – Jun 2 |
| Onions | Start seeds indoors (spring) | Feb 19 – Mar 18 |
| Onions | Transplant outdoors (spring) | Apr 19 – May 18 |
| Broccoli | Start seeds indoors (spring) | Mar 15 – Apr 18 |
| Broccoli | Transplant outdoors (spring) | Apr 19 – May 18 |
| Broccoli | Start seeds indoors (fall) | Jun 14 – Jun 24 |
| Broccoli | Transplant outdoors (fall) | Jul 14 – Jul 25 |
| Cabbage | Start seeds indoors (spring) | Mar 5 – Apr 2 |
| Cabbage | Transplant outdoors (spring) | Apr 2 – May 3 |
| Cabbage | Start seeds indoors (fall) | Jun 4 – Jul 4 |
| Cabbage | Transplant outdoors (fall) | Jul 4 – Aug 4 |
| Leaf lettuce | Sow outdoors (spring) | Apr 2 – Jun 18 |
| Leaf lettuce | Sow outdoors (fall) | Jul 4 – Aug 20 |
| Spinach | Sow outdoors (spring) | Mar 26 – May 9 |
| Spinach | Sow outdoors (fall) | Jul 21 – Aug 25 |
| Radishes | Sow outdoors (spring) | Apr 2 – May 23 |
| Radishes | Sow outdoors (fall) | Jul 4 – Sep 4 |
| Kale | Sow outdoors (spring) | Apr 19 – May 9 |
| Kale | Sow outdoors (fall) | Jun 27 – Aug 4 |
| Carrots | Sow outdoors (spring) | May 3 – Jun 18 |
| Carrots | Sow outdoors (fall) | Jun 4 – Jul 20 |
| Garlic | Plant outdoors (fall) | Oct 4 – Nov 4 |
Where these dates come from
ZIP code 48707 is matched to the NOAA station Auburn 2Ne, MI, 14.3 km away, at 605 ft elevation (24 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Auburn 2Ne, MI (used) | 605 ft | May 3 | Oct 14 |
| Essexville, MI | 588 ft | Apr 27 | Oct 20 |
| Saginaw Mbs Intl Ap, MI | 660 ft | Apr 26 | Oct 17 |
| Midland, MI | 640 ft | Apr 29 | Oct 16 |
Frost dates near Bay City
- Kawkawlin, MI 48631 · last May 3, first Oct 14
- Linwood, MI 48634 · last May 3, first Oct 14
- Pinconning, MI 48650 · last May 5, first Oct 10
- Bay City, MI 48706 · last May 3, first Oct 14
- Essexville, MI 48732 · last Apr 27, first Oct 20
- Auburn, MI 48611 · last May 3, first Oct 14
- University Center, MI 48710 · last May 3, first Oct 14
- Midland, MI 48642 · last Apr 29, first Oct 16
Frequently asked questions
- When is the last frost in Bay City, MI?
- For ZIP code 48707, the average last spring frost (32°F) is May 3, based on NOAA 1991-2020 climate normals for the Auburn 2Ne, MI weather station. There is a 1-in-10 chance of a frost after May 23.
- When is the first frost in Bay City, MI?
- The average first fall frost (32°F) is October 14. There is a 1-in-10 chance of frost by September 29, so tender plants are at risk from that point on.
- How long is the growing season in 48707?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 161 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.