Last frost date in Westbrook, ME
In Westbrook, the last spring frost comes around April 26 in an average year. Wait until May 7 if you want 90% odds of no more frost. The first fall frost usually arrives about October 15, which leaves 170 frost-free days. An early freeze before October 2 happens one year in ten.
- Safe after (10% risk)
- May 7
- Average first frost
- Oct 15
- Frost-free season
- 170 days
- Hard freeze (28°F) ends
- Apr 14
Frost likely tonight, low 32°F
National Weather Service forecast, updated Oct 22, 12:24 UTC
- ThuOct 2232°frost
- FriOct 2324°hard freeze
- SatOct 2426°hard freeze
- SunOct 2531°frost
- MonOct 2637°
- TueOct 2731°frost
- WedOct 2833°possible frost
Planting calendar for Westbrook
Windows count forward or back from the average frost dates above. Click a crop for dates across Maine.
Frost probabilities
| Threshold | Spring, 90% chance later | Spring, 50% | Spring, 10% | Fall, 10% chance earlier | Fall, 50% | Fall, 90% |
|---|---|---|---|---|---|---|
| Light frost, 32°F | Apr 16 | Apr 26 | May 7 | Oct 2 | Oct 15 | Oct 30 |
| Hard freeze, 28°F | Apr 3 | Apr 14 | Apr 25 | Oct 14 | Oct 27 | Nov 9 |
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 Portland International Jetport (USW00014764) sits 4.8 miles from the center of Westbrook at 45 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 Westbrook, ME?
The average last frost date in Westbrook is April 26, based on NOAA 1991–2020 climate normals. There is a 10% chance of frost after May 7.
When is the first frost in Westbrook?
The first frost in fall usually comes around October 15. One year in ten it arrives before October 2.
How long is the growing season in Westbrook?
About 170 days between the average last and first frost.
When should I plant tomatoes in Westbrook?
Plant tomato seedlings outside from May 3 to May 17. Start seeds indoors six to eight weeks earlier.