New Hampshire Frost Dates
New Hampshire has 55 NOAA weather stations with freeze records in the 1991–2020 climate normals. The typical last spring frost ranges from April 21 at Manchester Ap to May 31 at Colebrook 3sw; at half the stations it has come by May 8. The first fall frost typically arrives between September 18 at Bethlehem 2 and October 19 at Manchester Ap, with a median of October 4.
The growing season between the typical frosts runs from 112 days at Berlin Muni Ap to 180 days at Manchester Ap; 148 days at the median station.
At 1 station, a freeze is possible in any month.
Every station in New Hampshire
Typical dates have a 50% chance of a frost after them in spring, and before them in fall; safer dates, 10%. A garden can differ from its nearest station, especially in a valley or on a hillside: see why your garden may differ.
| Station | Elevation | Last frost | Safer | First frost | Safer | Season (days) |
|---|---|---|---|---|---|---|
| Benton 5 Sw | 1,200 ft | May 15 | Jun 3 | Sep 28 | Sep 12 | 133 |
| Berlin Muni Ap | 1,158 ft | May 30 | Jun 11 | Sep 19 | Sep 5 | 112 |
| Berlin | 920 ft | May 14 | May 30 | Sep 30 | Sep 15 | 135 |
| Bethlehem 2 | 1,180 ft | May 24 | Jun 8 | Sep 18 | Sep 6 | 116 |
| Bradford 2 | 815 ft | May 15 | May 29 | Sep 27 | Sep 15 | 135 |
| Colebrook 3sw | 1,120 ft | May 31 | Jun 14 | Sep 21 | Sep 7 | 112 |
| Concord Muni Ap | 346 ft | May 8 | May 22 | Oct 3 | Sep 21 | 146 |
| Durham 2 N | 119 ft | May 3 | May 16 | Oct 10 | Sep 27 | 158 |
| Durham 2 Ssw | 63 ft | May 7 | May 19 | Oct 4 | Sep 23 | 150 |
| Durham | 75 ft | May 8 | May 22 | Oct 4 | Sep 23 | 148 |
| E Milford | 240 ft | Apr 28 | May 12 | Oct 8 | Sep 28 | 161 |
| E Sandwich | 692 ft | May 6 | May 19 | Oct 6 | Sep 24 | 151 |
| Epping | 160 ft | May 7 | May 21 | Oct 4 | Sep 22 | 148 |
| Errol Ap | 1,240 ft | May 21 | Jun 3 | Sep 22 | Sep 9 | 123 |
| First Connecticut Lake | 1,650 ft | May 25 | Jun 8 | Sep 24 | Sep 9 | 121 |
| Franklin Falls Dam | 450 ft | May 7 | May 20 | Oct 3 | Sep 24 | 148 |
| Gorham Ap | 800 ft | May 14 | May 29 | Sep 26 | Sep 11 | 133 |
| Grafton | 830 ft | May 21 | Jun 5 | Sep 26 | Sep 12 | 127 |
| Greenland | 95 ft | May 4 | May 18 | Oct 8 | Sep 27 | 157 |
| Greenville 1 Nne | 900 ft | May 10 | May 27 | Oct 6 | Sep 25 | 147 |
| Hanover | 584 ft | May 1 | May 15 | Oct 13 | Oct 1 | 162 |
| Hopkinton Lake | 430 ft | May 6 | May 20 | Oct 1 | Sep 20 | 146 |
| Hudson 1 Sse | 185 ft | May 3 | May 16 | Oct 8 | Sep 27 | 156 |
| Jaffrey Muni Ap | 1,040 ft | May 5 | May 20 | Oct 6 | Sep 25 | 152 |
| Jaffrey Silver Rch Airpark | 1,030 ft | May 5 | May 19 | Oct 6 | Sep 25 | 154 |
| Jefferson | 1,235 ft | May 8 | May 23 | Oct 1 | Sep 16 | 146 |
| Keene | 511 ft | May 14 | May 28 | Oct 1 | Sep 18 | 138 |
| Lakeport 2 | 500 ft | Apr 30 | May 13 | Oct 18 | Oct 4 | 170 |
| Lancaster | 860 ft | May 18 | Jun 1 | Sep 30 | Sep 16 | 132 |
| Lebanon Muni Ap | 598 ft | May 9 | May 24 | Oct 6 | Sep 23 | 148 |
| Lincoln Nepp | 807 ft | May 7 | May 19 | Oct 4 | Sep 22 | 149 |
| Manchester Ap | 225 ft | Apr 21 | May 6 | Oct 19 | Oct 4 | 180 |
| Massabesic Lake | 253 ft | Apr 30 | May 14 | Oct 11 | Sep 30 | 164 |
| Meredith 3 Nne | 861 ft | Apr 28 | May 9 | Oct 16 | Oct 3 | 171 |
| Milford | 320 ft | May 3 | May 15 | Oct 5 | Sep 25 | 156 |
| Mt Sunapee | 1,275 ft | May 2 | May 17 | Oct 9 | Sep 27 | 158 |
| Mt Washington | 6,267 ft | A freeze is possible in any month | ||||
| N Conway | 522 ft | May 7 | May 19 | Oct 5 | Sep 23 | 150 |
| N Stratford | 950 ft | May 19 | Jun 2 | Sep 29 | Sep 15 | 131 |
| Nashua 2 Nnw | 135 ft | Apr 30 | May 11 | Oct 12 | Sep 30 | 165 |
| Nashua Cwsu | 180 ft | Apr 29 | May 11 | Oct 8 | Sep 28 | 162 |
| Newport | 770 ft | May 14 | May 29 | Oct 1 | Sep 19 | 140 |
| Pinkham Notch | 2,025 ft | May 18 | Jun 1 | Oct 1 | Sep 15 | 135 |
| Plymouth | 660 ft | May 20 | Jun 4 | Sep 27 | Sep 14 | 128 |
| Rochester Skyhaven Ap | 323 ft | Apr 30 | May 13 | Oct 9 | Sep 27 | 161 |
| Salisbury | 550 ft | May 14 | May 28 | Sep 29 | Sep 14 | 138 |
| Tamworth 4 | 541 ft | May 16 | May 30 | Sep 26 | Sep 10 | 129 |
| W Hampstead | 288 ft | Apr 30 | May 14 | Oct 11 | Sep 29 | 162 |
| Walpole 2s Nepp | 604 ft | May 8 | May 22 | Oct 3 | Sep 22 | 149 |
| Waterville Valley Nepp | 1,429 ft | May 15 | May 29 | Sep 28 | Sep 13 | 134 |
| Weare 2 Ne | 805 ft | May 9 | May 23 | Oct 5 | Sep 25 | 148 |
| Weare | 720 ft | May 2 | May 14 | Oct 8 | Sep 27 | 158 |
| Wentworth | 653 ft | May 12 | May 25 | Oct 6 | Sep 23 | 146 |
| Whitefield Mt Washington Ap | 1,074 ft | May 27 | Jun 10 | Sep 19 | Sep 8 | 116 |
| York Pond | 1,519 ft | May 23 | Jun 6 | Sep 22 | Sep 9 | 122 |
Plan your garden with these dates
Enter your ZIP code in the planner: it picks the nearest of these stations and dates every crop in your beds from its frosts. Free, in your browser.
Questions
When is the last frost in New Hampshire?
It depends on where you are. The typical last spring frost at New Hampshire's NOAA stations ranges from April 21 to May 31, and half of them have had it by May 8. Enter your ZIP code above for the station nearest you.
When is the first frost in New Hampshire?
Typically between September 18 and October 19, depending on the station; the median is October 4. Plan fall crops back from your own station's date.
What do "typical" and "safer" mean?
With the typical (50%) last-frost date, half of years still have a frost after it. With the safer (10%) date, only one year in ten does. In fall it's the other way around: the safer date is the earlier one.
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