Maine frost dates: Last spring and first autumn frost at every NOAA station, 1991-2020
Across Maine's 82 NOAA stations with frost dates, the median last spring frost (32°F) runs from April 21 in Woodland to June 2 in Allagash; for half of its places it comes after May 8.
- Typical last spring frost
- May 8median of 42 places
- Typical first autumn frost
- October 5median of 42 places
- Earliest last frost
- April 21Woodland
- Latest last frost
- June 2Allagash
When is the last frost in Maine, town by town?
Each date is NOAA's: "after May 8 in half of years" means the last 32°F night of spring came after May 8 in half of the years 1991-2020. By the 1-in-10 date, the last frost has passed in nine years out of ten.
Find your town in the list, or look up a ZIP code for the stations nearest it.
| Place or station | Last frost (median) | 1 in 10 after | First frost (median) | 1 in 10 before | Growing season | Zone |
|---|---|---|---|---|---|---|
| Woodland | April 21 | May 2 | October 26 | October 7 | 185 days | 5b |
| Lewiston | April 25 | May 6 | October 19 | October 5 | 177 days | – |
| PortlandPortland International Jetport | April 26 | May 7 | October 15 | October 2 | 170 days | 6a |
| Acadia National Park | April 27 | May 8 | October 22 | October 6 | 177 days | 6a |
| AugustaAugusta State Airport | April 27 | May 7 | October 16 | October 2 | 172 days | 6a |
| Newcastle | April 27 | May 10 | October 18 | October 3 | 172 days | 6a |
| Tenants Harbor | April 27 | May 8 | October 25 | October 10 | 178 days | 6b |
| West Rockport (1 mi NNW) | April 27 | May 9 | October 19 | October 5 | 175 days | 5b |
| Gray | April 28 | May 10 | October 19 | October 5 | 172 days | 6a |
| Westport Island | April 28 | May 9 | October 21 | October 5 | 175 days | – |
| Eastport | April 29 | May 11 | October 25 | October 8 | 178 days | – |
| Windham (2 mi NW) | April 30 | May 12 | October 20 | October 5 | 172 days | – |
| Cape Neddick | May 1 | May 14 | October 14 | October 1 | 165 days | – |
| Gardiner | May 1 | May 14 | October 11 | September 30 | 163 days | 5b |
| Orono | May 1 | May 14 | October 6 | September 24 | 157 days | – |
| Turner | May 1 | May 13 | October 10 | September 29 | 162 days | 6a |
| BrunswickBrunswick Naval Air Station | May 2 | May 14 | October 10 | September 29 | 160 days | 5b |
| WatervilleWaterville Trtmt Plant | May 2 | May 14 | October 10 | September 30 | 159 days | 5a |
| Wesley | May 2 | May 12 | October 15 | October 1 | 164 days | – |
| Jonesboro | May 3 | May 16 | October 9 | September 27 | 158 days | – |
| Poland | May 3 | May 16 | October 7 | September 27 | 157 days | 6a |
| BangorBangor International Airport | May 4 | May 17 | October 4 | September 23 | 152 days | 5a |
| Grand Lake Stream | May 4 | May 18 | October 10 | October 1 | 157 days | 5b |
| LincolnLincoln Sanitary District/Water Treatment Plant | May 4 | May 16 | October 6 | September 24 | 153 days | 4b |
| Rumford1 mi SSE | May 4 | May 17 | October 6 | September 26 | 155 days | – |
| Bridgton3 mi NW | May 5 | May 17 | October 5 | September 22 | 151 days | 5a |
| Robbinston | May 5 | May 18 | October 13 | October 1 | 160 days | 5b |
| Bethel6 mi SSE | May 6 | May 19 | October 2 | September 20 | 147 days | – |
| East Sangerville | May 6 | May 20 | October 7 | September 26 | 153 days | – |
| Frenchville Aroostook Airport | May 6 | May 21 | October 2 | September 18 | 147 days | 5a |
| Hartford | May 6 | May 21 | October 3 | September 23 | 148 days | 5b |
| Topsfield 2 | May 6 | May 18 | October 8 | September 28 | 155 days | 5b |
| Belfast | May 7 | May 21 | October 5 | September 24 | 151 days | 5b |
| CaribouCaribou Weather Office | May 7 | May 24 | October 1 | September 17 | 143 days | 4b |
| GreenvilleGreenville Maine Forestry Service | May 7 | May 20 | October 9 | September 27 | 153 days | 5a |
| New Sharon | May 7 | May 22 | October 2 | September 20 | 146 days | 5a |
| West Buxton (2 mi NNW) | May 7 | May 18 | October 4 | September 23 | 148 days | 5a |
| Corinna | May 8 | May 23 | October 3 | September 21 | 148 days | 4b |
| East Surry | May 8 | May 23 | October 9 | September 27 | 152 days | – |
| Madison | May 8 | May 20 | October 5 | September 24 | 149 days | 5a |
| MillinocketMillinocket Municipal Airport | May 8 | May 24 | October 1 | September 19 | 143 days | 5a |
| WiscassetWiscasset Airport | May 8 | May 20 | October 7 | September 24 | 151 days | 5b |
| Kennebunkport | May 9 | May 22 | October 3 | September 20 | 146 days | 6a |
| Millinocket station | May 9 | May 24 | October 5 | September 23 | 147 days | 4b |
| Bath | May 10 | May 23 | October 6 | September 25 | 149 days | 5b |
| Harmony | May 11 | May 25 | October 1 | September 18 | 141 days | 5a |
| Livermore Falls1 mi E | May 11 | May 24 | September 29 | September 16 | 138 days | 5a |
| Barnard | May 12 | May 26 | October 1 | September 18 | 141 days | 5a |
| East Hiram | May 12 | May 25 | October 1 | September 19 | 140 days | 5a |
| Rumford (6 mi SW) | May 12 | May 27 | September 29 | September 15 | 139 days | – |
| Long Falls Dam | May 13 | May 27 | September 30 | September 15 | 138 days | 4b |
| Moosehead | May 13 | May 29 | September 30 | September 16 | 137 days | 4b |
| OldOld Town (2 mi W) | May 13 | May 28 | September 28 | September 16 | 137 days | 5a |
| PattenPatten 2 | May 13 | May 30 | September 30 | September 18 | 138 days | 5a |
| VanceboroVanceboro No 2 | May 13 | May 28 | October 1 | September 20 | 139 days | 5a |
| Hollis | May 14 | May 28 | September 30 | September 16 | 136 days | 5a |
| Presque Isle | May 14 | June 1 | September 26 | September 10 | 131 days | 4b |
| Dover-FoxcroftDover-Foxcroft Wastewater Treatment Plant | May 15 | May 28 | September 28 | September 15 | 134 days | 5a |
| Durham | May 15 | May 28 | October 2 | September 20 | 139 days | 5a |
| Farmington | May 16 | June 1 | September 26 | September 14 | 130 days | 5a |
| Limestone4 mi NNW | May 16 | June 1 | September 24 | September 12 | 129 days | 4a |
| Sanford2 mi NNW | May 16 | May 29 | September 30 | September 18 | 136 days | 5b |
| Sebec Lake | May 16 | June 1 | October 1 | September 19 | 135 days | 4b |
| FryeburgFryeburg E Slopes Airport | May 17 | June 1 | September 25 | September 11 | 128 days | 4b |
| Millinocket Wastewater | May 17 | May 31 | September 29 | September 17 | 133 days | – |
| Andover 2 | May 19 | June 1 | September 25 | September 13 | 129 days | – |
| Houlton (5 mi N) | May 19 | June 2 | September 23 | September 9 | 125 days | – |
| Middle Dam | May 19 | May 31 | October 1 | September 19 | 133 days | 4b |
| Pittston Farm | May 20 | June 3 | September 23 | September 8 | 123 days | 4a |
| Pittston Farms Nepp | May 21 | June 4 | September 21 | September 9 | 122 days | – |
| Brassua Dam | May 23 | June 4 | September 29 | September 16 | 128 days | 4b |
| Fort Kent | May 23 | June 6 | September 24 | September 11 | 121 days | 4a |
| Rangeley | May 23 | June 3 | September 27 | September 14 | 127 days | 4a |
| Rangeley (2 mi NW) | May 23 | June 5 | September 24 | September 9 | 123 days | – |
| Van BurenVan Buren 2 | May 23 | June 5 | September 26 | September 11 | 125 days | 3b |
| Eustis | May 24 | June 6 | September 21 | September 6 | 118 days | 4b |
| Bridgewater | May 25 | June 7 | September 18 | September 4 | 115 days | 4a |
| Danforth | May 25 | June 8 | September 24 | September 8 | 119 days | 4b |
| Jackman | May 26 | June 7 | September 23 | September 8 | 119 days | 4b |
| HoultonHoulton International Airport | May 27 | June 10 | September 18 | September 5 | 115 days | 4a |
| Clayton Lake | May 30 | June 12 | September 13 | August 29 | 106 days | – |
| Allagash | June 2 | June 21 | September 15 | August 29 | 102 days | 3a |
Source: NOAA NCEI 1991-2020 annual normals (frost probabilities, growing-season length); station daily lows via ACIS (zone). Growing season: NOAA's median number of days between the last spring and first autumn 32°F night. Zone: the USDA's plant hardiness rule applied to the station's own 1991-2020 coldest nights.