Portland, ME Frost Dates
The last spring frost in Portland usually comes around April 26 and the first fall frost around October 15.
| Spring (last) | Fall (first) | |
|---|---|---|
| Frost, 32°F | April 26 | October 15 |
| Hard freeze, 28°F | April 14 | October 27 |
Growing season: about 170 days.
Frequently asked questions
When is the last frost in Portland, ME?
The median date of the last spring frost (32°F) is April 26. In half of years the last frost comes earlier and in half it comes later, so waiting a week or two past April 26 lowers the risk for tender plants.
When is the first frost in Portland?
The median date of the first fall frost (32°F) is October 15, and a hard freeze (28°F) usually follows around October 27.
How long is the growing season in Portland?
About 170 days between the median last spring frost and first fall frost.
NOAA NCEI U.S. Climate Normals 1991-2020, station USW00014764. Median (50% probability) dates. Low spots and valleys can frost later in spring and earlier in fall than the station.