Frost dates by state
Idaho Frost Dates
Across Idaho's 200 cities and towns, the average last spring frost runs from April 12 in Melba to June 22 in McCall. Average last frost elsewhere: Coeur d'Alene Apr 22, Pocatello May 2 and Idaho Falls May 9. In 14 towns, frost is possible in any month.
Frost dates for every city and town in Idaho
Dates are for 32°F at the NOAA station nearest the ZIP code at each Idaho town's center. "Safer date" is when only 1 year in 10 still gets a frost, a good target for tomatoes and peppers.
| City | Average last frost | Safer date | Average first frost | Frost-free days |
|---|---|---|---|---|
| Aberdeen | May 21 | Jun 13 | Sep 20 | 122 |
| Acequia | May 16 | Jun 5 | Oct 1 | 138 |
| Albion | Jun 5 | Jun 23 | Sep 13 | 100 |
| American Falls | May 20 | Jun 9 | Sep 26 | 129 |
| Ammon | May 9 | Jun 2 | Oct 1 | 145 |
| Arco | May 22 | Jun 9 | Sep 22 | 123 |
| Arimo | May 23 | Jun 10 | Sep 24 | 124 |
| Ashton | May 21 | Jun 13 | Sep 21 | 123 |
| Athol | May 22 | Jun 6 | Sep 22 | 123 |
| Bancroft | May 21 | Jun 11 | Sep 21 | 123 |
| Basalt | May 5 | May 22 | Oct 3 | 151 |
| Bellevue | May 13 | Jun 3 | Oct 2 | 142 |
| Blackfoot | May 5 | May 22 | Oct 3 | 151 |
| Bliss | May 3 | May 17 | Oct 1 | 151 |
| Bloomington | May 19 | Jun 5 | Sep 21 | 125 |
| Boise City | Apr 24 | May 9 | Oct 21 | 180 |
| Bonners Ferry | Apr 30 | May 16 | Oct 4 | 157 |
| Bovill | May 16 | Jun 1 | Sep 23 | 130 |
| Buhl | May 17 | Jun 5 | Sep 29 | 135 |
| Burley | May 7 | May 23 | Oct 4 | 150 |
| Butte City | May 22 | Jun 9 | Sep 22 | 123 |
| Caldwell | Apr 29 | May 18 | Oct 13 | 167 |
| Cambridge | May 10 | Jun 1 | Oct 2 | 145 |
| Carey | Jun 16 | Jun 30 | Sep 9 | 85 |
| Cascade | Jun 22 | Jul 10 | Sep 2 | 72 |
| Castleford | May 17 | Jun 5 | Sep 29 | 135 |
| Challis | May 14 | Jun 2 | Sep 25 | 134 |
| Chubbuck | May 16 | Jun 6 | Oct 2 | 139 |
| Clark Fork | May 9 | May 25 | Oct 8 | 152 |
| Clayton | Frost possible any month | |||
| Clifton | May 16 | Jun 4 | Sep 28 | 135 |
| Coeur d'Alene | Apr 22 | May 6 | Oct 18 | 179 |
| Cottonwood | May 6 | May 26 | Oct 13 | 160 |
| Council | May 10 | Jun 1 | Oct 2 | 145 |
| Craigmont | May 23 | Jun 19 | Sep 25 | 125 |
| Crouch | Jun 1 | Jun 20 | Sep 10 | 101 |
| Culdesac | May 23 | Jun 19 | Sep 25 | 125 |
| Dalton Gardens | Apr 22 | May 6 | Oct 18 | 179 |
| Dayton | May 16 | Jun 4 | Sep 28 | 135 |
| Deary | May 16 | Jun 1 | Sep 23 | 130 |
| Declo | Jun 5 | Jun 23 | Sep 13 | 100 |
| Dietrich | Apr 24 | May 12 | Oct 16 | 175 |
| Donnelly | Jun 22 | Jul 10 | Sep 2 | 72 |
| Dover | May 8 | May 25 | Sep 28 | 143 |
| Downey | May 31 | Jun 16 | Sep 18 | 110 |
| Driggs | Jun 13 | Jun 28 | Sep 9 | 88 |
| Drummond | May 21 | Jun 13 | Sep 21 | 123 |
| Dubois | May 18 | Jun 9 | Sep 30 | 135 |
| Eagle | Apr 24 | May 9 | Oct 21 | 180 |
| East Hope | May 8 | May 25 | Sep 28 | 143 |
| Eden | May 7 | May 26 | Oct 5 | 151 |
| Elk River | May 16 | Jun 1 | Sep 23 | 130 |
| Emmett | Apr 30 | May 17 | Oct 17 | 170 |
| Fairfield | Jun 16 | Jul 3 | Sep 6 | 82 |
| Ferdinand | May 6 | May 26 | Oct 13 | 160 |
| Fernan Lake Village | Apr 22 | May 6 | Oct 18 | 179 |
| Filer | Apr 25 | May 10 | Oct 15 | 173 |
| Firth | May 5 | May 22 | Oct 3 | 151 |
| Franklin | May 16 | Jun 4 | Sep 28 | 135 |
| Fruitland | Apr 23 | May 9 | Oct 13 | 173 |
| Garden City | May 17 | Jun 10 | Oct 12 | 148 |
| Genesee | Frost possible any month | |||
| Georgetown | Jun 17 | Jul 4 | Sep 3 | 78 |
| Glenns Ferry | May 1 | May 16 | Oct 3 | 155 |
| Gooding | May 3 | May 17 | Oct 1 | 151 |
| Grace | May 29 | Jun 16 | Sep 17 | 111 |
| Grand View | Apr 28 | May 13 | Oct 6 | 161 |
| Grangeville | May 9 | May 27 | Oct 3 | 147 |
| Greenleaf | Apr 24 | May 5 | Oct 9 | 168 |
| Hagerman | May 3 | May 17 | Oct 1 | 151 |
| Hailey | May 13 | Jun 3 | Oct 2 | 142 |
| Hamer | Jun 3 | Jun 21 | Sep 11 | 100 |
| Hansen | May 7 | May 26 | Oct 5 | 151 |
| Harrison | Apr 22 | May 6 | Oct 18 | 179 |
| Hauser | Apr 22 | May 6 | Oct 18 | 179 |
| Hayden | Apr 22 | May 6 | Oct 18 | 179 |
| Hayden Lake | Apr 22 | May 6 | Oct 18 | 179 |
| Hazelton | May 7 | May 26 | Oct 5 | 151 |
| Heyburn | May 7 | May 23 | Oct 4 | 150 |
| Hollister | May 9 | May 28 | Oct 4 | 148 |
| Homedale | Apr 24 | May 5 | Oct 9 | 168 |
| Hope | May 8 | May 25 | Sep 28 | 143 |
| Horseshoe Bend | May 17 | Jun 10 | Oct 12 | 148 |
| Huetter | Apr 22 | May 6 | Oct 18 | 179 |
| Idaho City | Jun 17 | Jul 4 | Sep 5 | 80 |
| Idaho Falls | May 9 | Jun 2 | Oct 1 | 145 |
| Inkom | May 16 | Jun 6 | Oct 2 | 139 |
| Iona | May 9 | Jun 2 | Oct 1 | 145 |
| Irwin | Frost possible any month | |||
| Island Park | Frost possible any month | |||
| Jerome | May 1 | May 16 | Oct 14 | 166 |
| Juliaetta | Frost possible any month | |||
| Kamiah | Apr 29 | May 12 | Oct 5 | 159 |
| Kellogg | May 14 | Jun 3 | Sep 26 | 135 |
| Kendrick | Apr 20 | May 5 | Oct 20 | 183 |
| Ketchum | Frost possible any month | |||
| Kimberly | May 6 | May 26 | Oct 3 | 150 |
| Kooskia | Apr 29 | May 12 | Oct 5 | 159 |
| Kootenai | May 8 | May 25 | Sep 28 | 143 |
| Kuna | Apr 24 | May 9 | Oct 21 | 180 |
| Lapwai | May 23 | Jun 19 | Sep 25 | 125 |
| Lava Hot Springs | May 21 | Jun 11 | Sep 21 | 123 |
| Leadore | Frost possible any month | |||
| Lewiston | May 23 | Jun 19 | Sep 25 | 125 |
| Lewisville | May 9 | May 25 | Oct 5 | 149 |
| Lost River | May 22 | Jun 9 | Sep 22 | 123 |
| Mackay | May 22 | Jun 9 | Sep 22 | 123 |
| Malad City | May 22 | Jun 16 | Sep 20 | 121 |
| Malta | Jun 1 | Jun 19 | Sep 19 | 110 |
| Marsing | Apr 24 | May 5 | Oct 9 | 168 |
| McCall | Jun 22 | Jul 10 | Sep 2 | 72 |
| McCammon | May 23 | Jun 10 | Sep 24 | 124 |
| Melba | Apr 12 | May 6 | Oct 26 | 197 |
| Menan | May 9 | May 25 | Oct 5 | 149 |
| Meridian | Apr 24 | May 9 | Oct 21 | 180 |
| Middleton | Apr 30 | May 17 | Oct 17 | 170 |
| Midvale | May 15 | Jun 4 | Sep 27 | 135 |
| Minidoka | May 16 | Jun 5 | Oct 1 | 138 |
| Montpelier | Jun 17 | Jul 4 | Sep 3 | 78 |
| Moore | May 22 | Jun 9 | Sep 22 | 123 |
| Moscow | Frost possible any month | |||
| Mountain Home | May 2 | May 23 | Oct 8 | 159 |
| Moyie Springs | Apr 30 | May 16 | Oct 4 | 157 |
| Mud Lake | Jun 3 | Jun 21 | Sep 11 | 100 |
| Mullan | May 12 | Jun 19 | Sep 30 | 141 |
| Murtaugh | May 7 | May 26 | Oct 5 | 151 |
| Nampa | Apr 29 | May 18 | Oct 13 | 167 |
| New Meadows | Frost possible any month | |||
| New Plymouth | Apr 22 | May 7 | Oct 9 | 170 |
| Newdale | May 29 | Jun 18 | Sep 13 | 107 |
| Nezperce | May 24 | Jun 19 | Sep 20 | 119 |
| Notus | Apr 27 | May 9 | Oct 9 | 165 |
| Oakley | May 15 | Jun 6 | Oct 2 | 140 |
| Oldtown | May 12 | May 29 | Sep 21 | 132 |
| Onaway | May 15 | Jun 2 | Sep 21 | 129 |
| Orofino | Apr 20 | May 5 | Oct 20 | 183 |
| Osburn | May 5 | May 21 | Oct 2 | 150 |
| Oxford | May 22 | Jun 16 | Sep 20 | 121 |
| Paris | Jun 17 | Jul 4 | Sep 3 | 78 |
| Parker | May 17 | Jun 10 | Sep 22 | 128 |
| Parma | Apr 27 | May 9 | Oct 9 | 165 |
| Paul | May 7 | May 23 | Oct 4 | 150 |
| Payette | Apr 23 | May 9 | Oct 13 | 173 |
| Peck | Apr 20 | May 5 | Oct 20 | 183 |
| Pierce | Jun 3 | Jun 29 | Sep 7 | 96 |
| Pinehurst | May 14 | Jun 3 | Sep 26 | 135 |
| Placerville | Jun 1 | Jun 20 | Sep 10 | 101 |
| Plummer | May 11 | Jun 4 | Oct 5 | 147 |
| Pocatello | May 2 | May 18 | Oct 11 | 162 |
| Ponderay | May 8 | May 25 | Sep 28 | 143 |
| Post Falls | Apr 22 | May 6 | Oct 18 | 179 |
| Potlatch | May 15 | Jun 2 | Sep 21 | 129 |
| Preston | May 16 | Jun 4 | Sep 28 | 135 |
| Priest River | May 12 | May 29 | Sep 21 | 132 |
| Rathdrum | Apr 22 | May 6 | Oct 18 | 179 |
| Reubens | May 23 | Jun 19 | Sep 25 | 125 |
| Rexburg | May 12 | Jun 2 | Sep 24 | 135 |
| Richfield | May 24 | Jun 14 | Sep 26 | 125 |
| Rigby | May 9 | May 25 | Oct 5 | 149 |
| Riggins | May 6 | May 26 | Oct 9 | 156 |
| Ririe | May 9 | May 25 | Oct 5 | 149 |
| Roberts | May 9 | May 25 | Oct 5 | 149 |
| Rockland | May 20 | Jun 9 | Sep 26 | 129 |
| Rupert | May 16 | Jun 5 | Oct 1 | 138 |
| Salmon | May 17 | Jun 9 | Sep 24 | 130 |
| Sandpoint | May 8 | May 25 | Sep 28 | 143 |
| Shelley | May 23 | Jun 13 | Sep 20 | 120 |
| Shoshone | Apr 24 | May 12 | Oct 16 | 175 |
| Smelterville | May 14 | Jun 3 | Sep 26 | 135 |
| Soda Springs | Frost possible any month | |||
| Spencer | May 18 | Jun 9 | Sep 30 | 135 |
| Spirit Lake | May 22 | Jun 6 | Sep 22 | 123 |
| St. Anthony | May 17 | Jun 10 | Sep 22 | 128 |
| St. Charles | May 15 | Jun 5 | Oct 4 | 142 |
| St. Maries | May 3 | May 18 | Oct 4 | 154 |
| Stanley | Frost possible any month | |||
| Star | Apr 30 | May 17 | Oct 17 | 170 |
| State Line | Apr 22 | May 6 | Oct 18 | 179 |
| Stites | Apr 30 | May 13 | Oct 11 | 164 |
| Sugar City | May 29 | Jun 18 | Sep 13 | 107 |
| Sun Valley | Frost possible any month | |||
| Swan Valley | Frost possible any month | |||
| Tensed | May 15 | Jun 2 | Sep 21 | 129 |
| Teton | May 29 | Jun 18 | Sep 13 | 107 |
| Tetonia | Jun 15 | Jun 29 | Sep 7 | 84 |
| Troy | Frost possible any month | |||
| Twin Falls | Apr 25 | May 10 | Oct 15 | 173 |
| Ucon | May 9 | Jun 2 | Oct 1 | 145 |
| Victor | Jun 13 | Jun 28 | Sep 9 | 88 |
| Wallace | May 5 | May 21 | Oct 2 | 150 |
| Wardner | May 14 | Jun 3 | Sep 26 | 135 |
| Warm River | May 21 | Jun 13 | Sep 21 | 123 |
| Weippe | Jun 3 | Jun 29 | Sep 7 | 96 |
| Weiser | Apr 23 | May 10 | Oct 13 | 173 |
| Wendell | May 2 | May 30 | Oct 14 | 165 |
| Weston | May 16 | Jun 4 | Sep 28 | 135 |
| White Bird | May 9 | May 27 | Oct 3 | 147 |
| Wilder | Apr 24 | May 5 | Oct 9 | 168 |
| Winchester | May 23 | Jun 19 | Sep 25 | 125 |
| Worley | May 11 | Jun 4 | Oct 5 | 147 |
Source: NOAA National Centers for Environmental Information, U.S. Climate Normals 1991–2020. City centers from the US Census Bureau. Click a city for its nearest station and, where it has frost dates, hard-freeze dates and a vegetable planting calendar. See how we calculate.
Frequently asked questions
When is the last frost in Coeur d'Alene, ID?
The average last spring frost in Coeur d'Alene is April 22, and only 1 year in 10 has a frost after May 6. The average first fall frost is October 18. These come from NOAA's 1991–2020 records at the Coeur D'alene station.
When should I plant tomatoes in Idaho?
UNH Extension times tomato transplants for 1 to 2 weeks after the average last frost. In Coeur d'Alene that's about Apr 29 to May 6. Look up your ZIP code for your own dates and a full vegetable planting calendar.
More for Idaho: Idaho climate zones (insulation) · Idaho planting zones · Frost line depth by state