Last frost date in Winchester, MA
The average last frost in Winchester is April 25. By May 8 the chance of another 32°F night drops to 1 in 10. The first fall frost usually arrives about October 17, which leaves 174 frost-free days. An early freeze before October 3 happens one year in ten.
- Safe after (10% risk)
- May 8
- Average first frost
- Oct 17
- Frost-free season
- 174 days
- Hard freeze (28°F) ends
- Apr 11
Frost likely Fri night, low 31°F
National Weather Service forecast, updated Oct 22, 12:24 UTC
- ThuOct 2238°
- FriOct 2331°frost
- SatOct 2432°frost
- SunOct 2537°
- MonOct 2644°
- TueOct 2739°
- WedOct 2841°
Planting calendar for Winchester
Windows count forward or back from the average frost dates above. Click a crop for dates across Massachusetts.
Frost probabilities
| Threshold | Spring, 90% chance later | Spring, 50% | Spring, 10% | Fall, 10% chance earlier | Fall, 50% | Fall, 90% |
|---|---|---|---|---|---|---|
| Light frost, 32°F | Apr 13 | Apr 25 | May 8 | Oct 3 | Oct 17 | Nov 1 |
| Hard freeze, 28°F | Mar 31 | Apr 11 | Apr 24 | Oct 14 | Oct 30 | Nov 11 |
Read the spring 10% column as the date after which only one year in ten still gets frost. That is the safer date for tomatoes, peppers and basil.
Where these numbers come from
NOAA station Reading (USC00196783) sits 5.0 miles from the center of Winchester at 110 feet. Its averages cover 1991 to 2020. Low spots, valleys and open fields can keep getting frost a week or two after the station stops; city centers and lakeshores usually get less of it.
Questions
When is the last frost in Winchester, MA?
The average last frost date in Winchester is April 25, based on NOAA 1991–2020 climate normals. There is a 10% chance of frost after May 8.
When is the first frost in Winchester?
The first frost in fall usually comes around October 17. One year in ten it arrives before October 3.
How long is the growing season in Winchester?
About 174 days between the average last and first frost.
When should I plant tomatoes in Winchester?
Plant tomato seedlings outside from May 2 to May 16. Start seeds indoors six to eight weeks earlier.