Montana · 90 stations
Montana Frost Dates: 90 Weather Stations
90 NOAA weather stations in Montana with at least 25 years of frost records.
| Station | Zone | Last spring frost (50%) | First fall frost (50%) | Frost-free days |
|---|---|---|---|---|
| Biddle, MT | 5a | May 14 | September 28 | 134 |
| Big Timber, MT | 5a | May 14 | September 26 | 133 |
| Billings, MT | 5a | May 10 | October 1 | 142 |
| Billings (Logan Airport), MT | 5b | May 4 | October 7 | 156 |
| Boulder, MT | 4b | June 7 | September 8 | 90 |
| Bozeman (Gallatin Field), MT | 4b | May 26 | September 16 | 112 |
| Brandenberg, MT | 4b | May 18 | September 22 | 126 |
| Bredette, MT | 3b | May 20 | September 21 | 122 |
| Brockway, MT | 4a | May 20 | September 19 | 121 |
| Busby, MT | 4a | May 23 | September 15 | 113 |
| Carlyle, MT | 4b | May 18 | September 29 | 134 |
| Cascade, MT | 4b | May 21 | September 19 | 120 |
| Chinook, MT | 3b | May 14 | September 23 | 130 |
| Choteau, MT | 4b | May 28 | September 12 | 104 |
| Circle, MT | 4a | May 17 | September 22 | 126 |
| Cohagen, MT | 4a | May 25 | September 14 | 110 |
| Columbus, MT | 4b | May 27 | September 14 | 108 |
| Conrad, MT | 4a | May 20 | September 19 | 119 |
| Content, MT | 3b | May 25 | September 14 | 110 |
| Creston, MT | 5b | May 12 | September 25 | 134 |
| Culbertson, MT | 3b | May 21 | September 20 | 120 |
| Cut Bank, MT | 4a | May 24 | September 15 | 113 |
| Dillon (Airport), MT | 5a | June 2 | September 13 | 101 |
| Ekalaka, MT | 4b | May 20 | September 23 | 126 |
| Ennis, MT | 5a | June 16 | September 4 | 78 |
| Fairfield, MT | 4b | May 13 | September 27 | 135 |
| Flatwillow, MT | 4b | May 16 | September 28 | 132 |
| Forsyth, MT | 4b | May 9 | September 29 | 142 |
| Fort Assiniboine, MT | 4a | May 15 | September 24 | 130 |
| Fort Peck Power Plant, MT | 4a | May 8 | October 1 | 145 |
| Gildford, MT | 3b | May 24 | September 15 | 114 |
| Glasgow, MT | 4a | May 6 | September 30 | 145 |
| Glasgow #2, MT | 4a | May 3 | October 1 | 151 |
| Glendive, MT | 4a | May 3 | October 4 | 153 |
| Grass Range, MT | 4b | May 20 | September 24 | 126 |
| Great Falls, MT | 4b | May 19 | September 24 | 126 |
| Hardin, MT | 4b | May 13 | September 29 | 135 |
| Havre, MT | 4a | May 15 | September 23 | 129 |
| Helena, MT | 5a | May 9 | September 30 | 142 |
| Holter Dam, MT | 4b | May 19 | September 24 | 124 |
| Hysham, MT | 4b | May 10 | September 29 | 141 |
| Hysham 25 SSE, MT | 4a | May 26 | September 16 | 111 |
| Ingomar, MT | 4a | May 21 | September 19 | 120 |
| Lewistown, MT | 4b | May 23 | September 21 | 119 |
| Libby Dam (Base), MT | 6a | May 11 | October 1 | 142 |
| Lindbergh Lake, MT | 5a | May 20 | September 22 | 120 |
| Loma, MT | 3b | May 20 | September 19 | 120 |
| Malta, MT | 4a | May 16 | September 23 | 128 |
| Melstone, MT | 4b | May 10 | September 29 | 141 |
| Melville, MT | 4b | June 9 | September 7 | 88 |
| Mildred, MT | 4a | May 20 | September 22 | 124 |
| Millegan, MT | 4a | June 11 | September 6 | 86 |
| Mizpah, MT | 4a | May 22 | September 15 | 117 |
| Moorhead, MT | 4b | May 17 | September 22 | 126 |
| Mystic Lake, MT | 5a | June 5 | September 14 | 99 |
| Norris Madison Power House, MT | 5b | April 30 | October 10 | 162 |
| Nye #2, MT | 5a | June 1 | September 11 | 100 |
| Opheim, MT | 3b | June 5 | September 2 | 89 |
| Plevna, MT | 4a | May 21 | September 20 | 121 |
| Powderville, MT | 4a | May 13 | September 25 | 132 |
| Rapelje, MT | 4b | May 24 | September 21 | 116 |
| Ridgeway, MT | 4a | May 17 | September 22 | 127 |
| Roundup, MT | 4b | May 20 | September 21 | 124 |
| Ryegate, MT | 4b | May 26 | September 18 | 112 |
| Saco, MT | 3b | May 15 | September 23 | 130 |
| Savage, MT | 4a | May 12 | September 25 | 135 |
| Scobey, MT | 3b | May 28 | September 6 | 99 |
| Sidney, MT | 4a | May 11 | September 27 | 137 |
| Simpson 6 N - Wildhorse, MT | 3b | May 26 | September 15 | 110 |
| Sonnette, MT | 4b | May 25 | September 19 | 115 |
| Stanford, MT | 4b | May 25 | September 21 | 118 |
| Stevensville, MT | 5b | May 22 | September 19 | 115 |
| Sun River, MT | 4a | June 2 | September 10 | 96 |
| Terry, MT | 4a | May 12 | September 28 | 137 |
| Townsend, MT | 4b | May 19 | September 19 | 122 |
| Trident, MT | 4b | May 9 | September 27 | 139 |
| Turner, MT | 4a | May 19 | September 21 | 124 |
| Twin Bridges, MT | 5a | June 8 | September 2 | 82 |
| Valentine, MT | 4a | May 18 | September 21 | 124 |
| Vida, MT | 4a | May 16 | September 22 | 129 |
| West Glacier, MT | 5a | May 18 | September 20 | 124 |
| Westby, MT | 3b | May 18 | September 21 | 125 |
| Yellowtail Dam, MT | 5b | May 7 | October 5 | 151 |
| near Bozeman, MT | 5a | May 26 | September 22 | 116 |
| near Butte, MT | 4a | June 13 | September 5 | 83 |
| near Dillon, MT | 5a | June 5 | September 13 | 98 |
| near Four Corners, MT | 5a | May 23 | September 23 | 123 |
| near Kalispell, MT | 5b | May 31 | September 10 | 100 |
| near Miles City, MT | 4b | May 8 | September 30 | 144 |
| near Thompson Falls, MT | 6b | May 7 | October 4 | 150 |