Montana Frost Dates
The median last spring freeze and first fall freeze (32°F) at 216 NOAA stations in Montana, 1991-2020, with the growing season between them.
Every station
A median date has an even chance of a later freeze in spring or an earlier one in fall. Each town page gives the dates at 36, 32 and 28°F and every probability from 10 to 90 percent.
| Station | Elevation | Last freeze | First freeze | Season, days | Town page |
|---|---|---|---|---|---|
| Adel | 5,017 ft | June 4 | September 12 | 100 | Cascade |
| Alberton | 3,060 ft | May 18 | September 25 | 130 | Frenchtown |
| Albion 1 N | 3,312 ft | June 2 | September 6 | 96 | |
| Alder 17 S | 5,850 ft | June 6 | September 14 | 100 | Virginia City |
| Anaconda | 5,230 ft | June 1 | September 14 | 105 | Anaconda |
| Augusta | 4,070 ft | May 19 | September 21 | 125 | Fairfield |
| Austin 1 W | 4,851 ft | June 4 | September 14 | 102 | Helena West Side |
| Baker | 2,933 ft | May 12 | September 26 | 137 | Baker |
| Baker Muni AP | 2,971 ft | May 16 | September 26 | 133 | Baker |
| Biddle 8 Sw | 3,631 ft | May 14 | September 28 | 137 | Broadus |
| Big Sandy | 2,770 ft | May 17 | September 25 | 131 | Big Sandy |
| Big Timber | 4,100 ft | May 14 | September 26 | 135 | Big Timber |
| Bigfork 13 S | 2,979 ft | May 1 | October 15 | 167 | Woods Bay |
| Billings Logan Intl AP | 3,581 ft | May 4 | October 7 | 156 | Billings |
| Billings WFO | 3,185 ft | May 5 | October 3 | 151 | Billings |
| Billings Wtp | 3,097 ft | May 10 | October 1 | 144 | Billings |
| Blackleaf | 4,235 ft | June 9 | September 3 | 86 | Choteau |
| Boulder | 4,904 ft | June 7 | September 8 | 93 | Boulder |
| Bozeman 6 W Exp Farm | 4,775 ft | May 23 | September 23 | 123 | King Arthur Park |
| Bozeman Gallatin Fld | 4,427 ft | May 26 | September 16 | 113 | Belgrade |
| Bozeman Montana State Univ | 4,913 ft | May 26 | September 22 | 119 | Bozeman |
| Brady 27 Ene (the Knees) | 3,325 ft | May 13 | September 29 | 139 | Conrad |
| Brandenberg | 2,770 ft | May 18 | September 22 | 127 | Ashland |
| Bredette | 2,313 ft | May 20 | September 21 | 124 | Scobey |
| Bridger 2 N | 3,583 ft | May 14 | September 24 | 133 | Bridger |
| Broadus | 3,032 ft | May 16 | September 28 | 135 | Broadus |
| Brockway 3 Wsw | 2,630 ft | May 20 | September 19 | 122 | Circle |
| Busby | 3,430 ft | May 23 | September 15 | 115 | Busby |
| Butte Bert Mooney AP | 5,506 ft | June 13 | September 5 | 84 | Butte |
| Bynum 4 Sse | 4,039 ft | May 16 | September 27 | 134 | Choteau |
| Carlyle 13 Nw | 3,145 ft | May 18 | September 29 | 134 | Wibaux |
| Carter 14 W | 3,450 ft | May 23 | September 23 | 123 | Black Eagle |
| Cascade 5 S | 3,360 ft | May 21 | September 19 | 121 | Cascade |
| Chester | 3,132 ft | May 24 | September 17 | 116 | Chester |
| Chinook | 2,420 ft | May 14 | September 23 | 132 | Chinook |
| Chinook 35SE | 3,360 ft | May 23 | September 23 | 123 | Hays |
| Choteau | 3,845 ft | May 28 | September 12 | 107 | Choteau |
| Choteau 8NE | 3,741 ft | May 20 | September 22 | 125 | Choteau |
| Circle | 2,480 ft | May 17 | September 22 | 128 | Circle |
| Cohagen | 2,720 ft | May 25 | September 14 | 112 | Jordan |
| Colstrip | 3,218 ft | May 15 | September 30 | 138 | Colstrip |
| Columbus | 3,602 ft | May 27 | September 14 | 110 | Columbus |
| Conrad | 3,550 ft | May 20 | September 19 | 122 | Conrad |
| Content 4 Nne | 2,325 ft | May 25 | September 14 | 112 | Malta |
| Creston | 2,935 ft | May 12 | September 25 | 136 | Evergreen |
| Culbertson | 1,940 ft | May 21 | September 20 | 122 | Culbertson |
| Cut Bank Muni AP | 3,838 ft | May 24 | September 15 | 114 | Cut Bank |
| Darby | 3,880 ft | May 24 | September 23 | 122 | Darby |
| Del Bonita | 4,337 ft | May 28 | September 16 | 111 | North Browning |
| Denton | 3,610 ft | June 1 | September 11 | 102 | Stanford |
| Dillon AP | 5,200 ft | June 2 | September 13 | 103 | Dillon |
| Dillon U Of Montana Western | 5,129 ft | June 5 | September 13 | 100 | Dillon |
| Divide | 5,350 ft | June 10 | September 7 | 89 | Butte |
| Dunkirk 19NNE | 3,323 ft | May 23 | September 14 | 114 | Shelby |
| E Glacier | 4,806 ft | June 8 | September 5 | 89 | South Browning |
| Ekalaka | 3,432 ft | May 20 | September 23 | 126 | Ekalaka |
| Elliston | 5,080 ft | June 9 | September 8 | 91 | Helena West Side |
| Ennis | 4,953 ft | June 16 | September 4 | 80 | Ennis |
| Eureka RS | 2,532 ft | May 11 | September 27 | 139 | Eureka |
| Fairfield | 3,983 ft | May 13 | September 27 | 137 | Fairfield |
| Flatwillow 4 Ene | 3,292 ft | May 16 | September 28 | 135 | Winnett |
| Forsyth | 2,515 ft | May 9 | September 29 | 143 | Forsyth |
| Fortine 1 N | 3,000 ft | May 16 | September 18 | 125 | Trego |
| Ft Assiniboine | 2,675 ft | May 15 | September 24 | 132 | Havre |
| Ft Belknap 2 Sw | 2,527 ft | May 16 | September 22 | 129 | Fort Belknap Agency |
| Ft Benton | 2,649 ft | May 15 | September 22 | 130 | Fort Benton |
| Ft Peck Pwr Plt | 2,071 ft | May 8 | October 1 | 146 | Glasgow |
| Gardiner | 5,275 ft | May 21 | September 27 | 129 | Gardiner |
| Geraldine | 3,145 ft | May 14 | September 26 | 135 | Fort Benton |
| Gibson 2 Ne | 4,444 ft | May 27 | September 18 | 114 | Ryegate |
| Gibson Dam | 4,590 ft | June 12 | September 8 | 88 | Choteau |
| Gildford | 2,820 ft | May 24 | September 15 | 114 | Big Sandy |
| Glasgow #2 | 2,090 ft | May 3 | October 1 | 151 | Glasgow |
| Glasgow Intl AP | 2,285 ft | May 6 | September 30 | 147 | Glasgow |
| Glendive | 2,075 ft | May 3 | October 4 | 154 | Glendive |
| Grass Range | 3,490 ft | May 20 | September 24 | 127 | Winnett |
| Great Falls 16ST | 3,505 ft | May 6 | October 1 | 148 | Great Falls |
| Great Falls Intl AP | 3,664 ft | May 19 | September 24 | 128 | Great Falls |
| Great Falls WFO | 3,705 ft | May 12 | September 28 | 139 | Great Falls |
| Hamilton | 3,585 ft | May 21 | September 22 | 124 | Hamilton |
| Hardin | 2,880 ft | May 13 | September 29 | 139 | Hardin |
| Harlem | 2,371 ft | May 16 | September 21 | 128 | Harlem |
| Harlem 20S | 2,695 ft | May 24 | September 22 | 121 | Hays |
| Harlowton | 4,222 ft | May 23 | September 16 | 116 | Harlowton |
| Harlowton 11NW | 4,954 ft | May 30 | September 20 | 113 | Harlowton |
| Havre City CO AP | 2,585 ft | May 15 | September 23 | 131 | Havre |
| Hebgen Dam | 6,489 ft | June 15 | September 10 | 87 | West Yellowstone |
| Helena Rgnl AP | 3,828 ft | May 9 | September 30 | 144 | Helena Valley Southeast |
| Heron 2 Nw | 2,240 ft | May 20 | September 20 | 123 | |
| Highwood 7 Ne | 3,600 ft | May 7 | October 2 | 148 | Fort Benton |
| Hinsdale 4 Sw | 2,805 ft | May 15 | September 26 | 134 | Glasgow |
| Holter Dam | 3,487 ft | May 19 | September 24 | 128 | Helena Valley Northwest |
| Hungry Horse Dam | 3,160 ft | May 9 | October 1 | 145 | Martin City |
| Huntley Exp Stn | 3,034 ft | May 12 | September 25 | 136 | Worden |
| Hysham | 2,669 ft | May 10 | September 29 | 142 | Hysham |
| Hysham 25 Sse | 3,100 ft | May 26 | September 16 | 113 | Colstrip |
| Ingomar 9 E | 2,800 ft | May 21 | September 19 | 121 | Hysham |
| Joliet | 3,838 ft | May 29 | September 15 | 109 | Joliet |
| Joplin | 3,323 ft | May 21 | September 19 | 121 | Chester |
| Jordan | 2,620 ft | May 21 | September 18 | 120 | Jordan |
| Jordan AP | 2,662 ft | May 18 | September 20 | 125 | Jordan |
| Judith Gap | 4,630 ft | June 1 | September 15 | 106 | Harlowton |
| Judith Gap 13 E | 4,791 ft | June 3 | September 15 | 104 | Harlowton |
| Kalispell Glacier AP | 2,957 ft | May 31 | September 10 | 102 | Evergreen |
| Laurin 2NE | 5,198 ft | May 24 | September 22 | 121 | Sheridan |
| Lewistown | 3,911 ft | May 14 | September 28 | 137 | Lewistown |
| Lewistown 11 Sse | 4,965 ft | May 31 | September 14 | 106 | Lewistown |
| Lewistown 11ESE | 5,028 ft | May 19 | September 25 | 129 | Lewistown |
| Lewistown 42 Wsw | 5,070 ft | June 15 | September 4 | 81 | Stanford |
| Lewistown Muni AP | 4,145 ft | May 23 | September 21 | 121 | Lewistown |
| Libby | 2,140 ft | May 10 | September 26 | 139 | Libby |
| Libby 1 Ne RS | 2,096 ft | May 23 | September 21 | 121 | Libby |
| Libby Dam (base) | 2,110 ft | May 11 | October 1 | 143 | White Haven |
| Lima | 6,279 ft | June 11 | September 10 | 91 | |
| Lindbergh Lake | 4,320 ft | May 20 | September 22 | 125 | Saint Ignatius |
| Livingston 12 S | 5,044 ft | May 19 | September 25 | 129 | Pray |
| Livingston Mission Fld | 4,643 ft | May 27 | September 14 | 110 | Livingston |
| Logan Landfill | 4,243 ft | May 26 | September 15 | 112 | Manhattan |
| Loma | 2,578 ft | May 20 | September 19 | 122 | Fort Benton |
| Malta | 2,262 ft | May 10 | September 29 | 142 | Malta |
| Malta 35 S | 2,615 ft | May 16 | September 23 | 130 | Hays |
| Malta 7 E | 2,231 ft | May 7 | September 28 | 144 | Malta |
| Martinsdale 3 Nnw | 4,800 ft | June 3 | September 8 | 97 | Harlowton |
| Medicine Lake 3 Se | 1,942 ft | May 16 | September 18 | 125 | Plentywood |
| Melstone | 2,932 ft | May 10 | September 29 | 142 | Roundup |
| Melville 4 W | 5,365 ft | June 9 | September 7 | 90 | Big Timber |
| Mildred 5 N | 2,482 ft | May 20 | September 22 | 125 | Terry |
| Miles City F Wiley Fld | 2,624 ft | May 8 | September 30 | 145 | Miles City |
| Millegan 14 Se | 4,970 ft | June 11 | September 6 | 87 | White Sulphur Springs |
| Missoula 2 Ne | 3,420 ft | May 10 | October 1 | 144 | East Missoula |
| Missoula 6 Nw WFO | 3,197 ft | May 6 | October 4 | 151 | Wye |
| Missoula Intl AP | 3,192 ft | May 16 | September 26 | 133 | Wye |
| Mizpah 4 Nnw | 2,480 ft | May 22 | September 15 | 116 | Miles City |
| Moccasin Exp Stn | 4,300 ft | May 28 | September 20 | 115 | Stanford |
| Moorhead 9 Ne | 3,220 ft | May 17 | September 22 | 128 | Broadus |
| Mosby 4 Ene | 2,910 ft | May 5 | October 4 | 152 | Winnett |
| Mystic Lake | 6,544 ft | June 5 | September 14 | 101 | Absarokee |
| Nashua #2 | 2,067 ft | May 12 | September 24 | 135 | Glasgow |
| Neihart 8 Nnw | 5,230 ft | June 6 | September 12 | 98 | Belt |
| Norris Madison Pwr House | 4,745 ft | April 30 | October 10 | 163 | Ennis |
| Nye #2 | 4,840 ft | June 1 | September 11 | 102 | Absarokee |
| Opheim 10 N | 2,878 ft | June 1 | September 7 | 98 | Scobey |
| Opheim 12 Sse | 2,936 ft | June 5 | September 2 | 89 | Glasgow |
| Plentywood | 2,048 ft | May 25 | September 14 | 112 | Plentywood |
| Plevna | 2,780 ft | May 21 | September 20 | 122 | Baker |
| Polson | 3,010 ft | May 10 | October 5 | 148 | Polson |
| Pompeys Pillar 15N | 3,390 ft | May 22 | September 22 | 123 | Worden |
| Port Of Morgan | 2,830 ft | May 19 | September 22 | 126 | Malta |
| Powderville 8 Nne | 2,800 ft | May 13 | September 25 | 135 | Ekalaka |
| Rapelje | 4,068 ft | May 24 | September 21 | 120 | Ryegate |
| Raymond Border Stn | 2,345 ft | May 19 | September 23 | 127 | Plentywood |
| Raynesford 2 Nnw | 4,215 ft | May 22 | September 23 | 124 | Belt |
| Red Lodge | 5,646 ft | June 3 | September 19 | 108 | Red Lodge |
| Redstone | 2,106 ft | May 28 | September 7 | 102 | Plentywood |
| Ridgeway 1 S | 3,316 ft | May 17 | September 22 | 128 | Ekalaka |
| Rock Springs | 3,024 ft | May 15 | September 25 | 133 | Miles City |
| Rogers Pass 9 Nne | 4,200 ft | May 21 | September 15 | 117 | Lincoln |
| Roundup | 3,200 ft | May 20 | September 21 | 124 | Roundup |
| Roundup 15 Sw | 3,386 ft | May 22 | September 15 | 116 | Roundup |
| Roy 8 Ne | 3,085 ft | May 14 | September 24 | 133 | Hays |
| Rudyard 19S | 2,878 ft | May 23 | September 19 | 119 | Chester |
| Rudyard 21 N | 3,000 ft | May 30 | September 11 | 104 | Chester |
| Ryegate | 3,650 ft | May 17 | September 23 | 129 | Ryegate |
| Ryegate 18 Nnw | 4,440 ft | May 26 | September 18 | 115 | Ryegate |
| Saco 1 Nnw | 2,185 ft | May 15 | September 23 | 131 | Malta |
| Saint Ignatius | 2,915 ft | May 12 | October 2 | 143 | Saint Ignatius |
| Sand Creek | 2,910 ft | May 12 | September 27 | 138 | Hays |
| Savage | 1,978 ft | May 12 | September 25 | 136 | Sidney |
| Scobey 4 Nw | 2,390 ft | May 28 | September 6 | 101 | Scobey |
| Shelby | 3,325 ft | May 23 | September 16 | 116 | Shelby |
| Shonkin 7 S | 4,300 ft | May 24 | September 21 | 120 | Belt |
| Sidney | 1,933 ft | May 11 | September 27 | 139 | Sidney |
| Simpson 6 N - Wildhorse | 2,815 ft | May 26 | September 15 | 112 | Havre North |
| Skq Dam | 2,730 ft | May 15 | September 28 | 136 | Polson |
| Sonnette 7 Sw | 3,914 ft | May 25 | September 19 | 117 | Ashland |
| St Marie | 2,756 ft | May 13 | September 27 | 137 | Glasgow |
| St Mary | 4,560 ft | June 12 | September 5 | 85 | North Browning |
| St. Mary 1 Ssw | 4,555 ft | June 3 | September 8 | 97 | North Browning |
| Stanford | 4,860 ft | May 25 | September 21 | 119 | Stanford |
| Stevensville | 3,375 ft | May 22 | September 19 | 120 | Stevensville |
| Sun Rvr 4 S | 3,600 ft | June 2 | September 10 | 100 | Vaughn |
| Sunburst 8 E | 3,700 ft | May 17 | September 25 | 131 | Shelby |
| Superior | 2,710 ft | May 17 | September 23 | 129 | Superior |
| Swan Lake | 3,100 ft | May 17 | September 19 | 125 | Woods Bay |
| Sweetgrass | 3,510 ft | May 15 | September 25 | 133 | Cut Bank |
| Terry | 2,250 ft | May 12 | September 28 | 139 | Terry |
| Terry 21 Nnw | 3,142 ft | May 26 | September 17 | 114 | Terry |
| Thompson Falls Ph | 2,380 ft | May 7 | October 4 | 150 | Thompson Falls |
| Tiber Dam | 2,850 ft | May 16 | September 23 | 130 | Chester |
| Tizer Gardens | 4,672 ft | June 18 | September 5 | 79 | Clancy |
| Townsend 3SE | 3,964 ft | May 19 | September 19 | 123 | Townsend |
| Trident | 4,036 ft | May 9 | September 27 | 141 | Three Forks |
| Trout Creek RS | 2,356 ft | May 20 | September 21 | 124 | Thompson Falls |
| Troy | 1,929 ft | May 14 | September 25 | 134 | Troy |
| Turner 11N | 2,982 ft | May 19 | September 21 | 125 | Harlem |
| Twin Bridges | 4,625 ft | June 8 | September 2 | 86 | Sheridan |
| Valentine | 2,905 ft | May 18 | September 21 | 126 | Winnett |
| Valier | 3,807 ft | May 17 | September 24 | 130 | Valier |
| Vida 6 Ne | 2,284 ft | May 16 | September 22 | 129 | Poplar |
| Virginia City | 5,773 ft | June 4 | September 18 | 106 | Virginia City |
| W Glacier | 3,148 ft | May 18 | September 20 | 125 | Coram |
| Westby | 2,103 ft | May 18 | September 21 | 126 | Plentywood |
| Western Ag Rsch Ctr | 3,608 ft | May 23 | September 21 | 121 | Corvallis |
| White Sulphur Springs #2 | 5,040 ft | June 4 | September 11 | 99 | White Sulphur Springs |
| Whitefish | 3,100 ft | May 16 | September 25 | 132 | Whitefish |
| Wibaux 2 E | 2,696 ft | May 27 | September 16 | 112 | Wibaux |
| Wilsall 1S | 5,015 ft | June 4 | September 6 | 94 | Livingston |
| Wilsall 8 Ene | 5,865 ft | June 8 | September 7 | 91 | Livingston |
| Winifred | 3,243 ft | May 16 | September 23 | 130 | Lewistown |
| Wolf Point 29 Ene | 2,085 ft | May 24 | September 14 | 113 | Poplar |
| Wolf Point 34 Ne | 2,643 ft | May 13 | September 28 | 138 | Scobey |
| Wolf Point Intl AP | 1,986 ft | May 16 | September 20 | 127 | Wolf Point |
| Wolf Pt | 2,090 ft | May 8 | September 28 | 143 | Wolf Point |
| Wyola 1 Sw | 3,730 ft | May 21 | September 17 | 119 | |
| Yellowtail Dam | 3,305 ft | May 7 | October 5 | 151 | Pryor |
| Zortman | 4,035 ft | May 18 | September 23 | 128 | Hays |
Sources
NOAA NCEI U.S. Climate Normals, 1991-2020, annual and seasonal freeze probabilities. Public domain.