Colorado frost dates
Across 210 weather stations in Colorado, the median last spring frost runs from Apr 14 in Grand Junction to Jun 21 in Vail, and the first fall frost from Sep 2 to Oct 26.
Colorado at a glance
- Weather stations
- 210
- Earliest last frost
- Apr 14 Grand Junction
- Latest last frost
- Jun 21 Vail
- Longest season
- 190 days Grand Junction
- Typical season
- about 145 frost-free days
- Hardiness zones
- Zones 4b to 7a
Frost dates by weather station
| Weather station | Last spring frost | First fall frost | Frost-free days | Zone |
|---|---|---|---|---|
| Akron | May 8 | Oct 6 | 149 | 5b |
| Akron Washington County Airport | May 6 | Oct 8 | 155 | 5b |
| Alamosa | May 30 | Sep 17 | 108 | 4b |
| Alamosa San Luis Airport | Jun 7 | Sep 15 | 98 | 4b |
| Allenspark | Jun 14 | Sep 12 | 92 | 5b |
| Altenbern | May 25 | Sep 25 | 120 | 6b |
| Arapahoe 12 mi S | May 5 | Oct 9 | 156 | 6a |
| Arapahoe 14 mi N | May 9 | Oct 7 | 150 | 6a |
| Aspen | Jun 2 | Sep 23 | 113 | 5b |
| Aspen Pitkin County Airport | May 31 | Sep 23 | 114 | 5b |
| Bailey | Jun 16 | Sep 8 | 84 | 5b |
| Black Canyon of the Gunnison | May 23 | Oct 1 | 130 | 6b |
| Black Forest | May 11 | Oct 6 | 147 | 5b |
| Blanca | May 25 | Sep 22 | 117 | 5a |
| Blue Mesa Lake | Jun 9 | Sep 16 | 96 | 5b |
| Bonny Dam | May 5 | Oct 10 | 155 | 6a |
| Boulder | May 6 | Oct 5 | 151 | 6a |
| Boulder 14 mi W | Jun 21 | Sep 2 | 71 | 5b |
| Briggsdale | May 12 | Sep 28 | 135 | 5a |
| Brighton | May 3 | Oct 7 | 155 | 5b |
| Buckhorn Mountain | May 21 | Sep 29 | 128 | 5b |
| Buena Vista | May 27 | Sep 23 | 116 | 5b |
| Burlington | May 6 | Oct 9 | 155 | 6a |
| Burlington Carson Airport | May 2 | Oct 10 | 160 | 6a |
| Byers | May 13 | Oct 2 | 142 | 5b |
| Cabin Creek | Jun 6 | Sep 19 | 103 | 5a |
| Campo | Apr 29 | Oct 13 | 166 | 6b |
| Canon City | May 4 | Oct 7 | 153 | 6a |
| Castle Rock | May 9 | Oct 2 | 143 | 5b |
| Cedaredge | May 3 | Oct 9 | 156 | 5b |
| Center | May 24 | Sep 24 | 120 | 5a |
| Cheesman | May 17 | Oct 1 | 135 | 5b |
| Cheraw | Apr 30 | Oct 10 | 163 | 6a |
| Cherry Creek Dam | May 7 | Oct 8 | 152 | 6a |
| Cheyenne Wells | May 1 | Oct 14 | 165 | 6a |
| Cimarron | Jun 20 | Sep 10 | 81 | 5b |
| Coal Creek Canyon | Jun 5 | Sep 16 | 103 | 5b |
| Cochetopa Creek | Jun 21 | Sep 5 | 74 | 4b |
| Collbran | May 17 | Sep 30 | 136 | 5b |
| Colorado National Monument | Apr 26 | Oct 16 | 172 | 7a |
| Colorado Springs Municipal Airport | May 3 | Oct 8 | 158 | 6a |
| Cortez | May 12 | Oct 7 | 147 | 7a |
| Cortez 8 mi SE | May 6 | Oct 14 | 158 | 7a |
| Cortez Montezuma County Airport | May 27 | Sep 28 | 125 | 7a |
| Craig | May 29 | Sep 20 | 113 | 5b |
| Craig Moffat County Airport | Jun 6 | Sep 12 | 96 | 5b |
| Crestone | May 26 | Sep 26 | 120 | 5a |
| Cripple Creek | May 26 | Sep 26 | 121 | 5b |
| Crook | May 11 | Oct 4 | 145 | 5b |
| Cumbre Vista - Colorado Springs | May 9 | Oct 6 | 150 | 5b |
| Del Norte | May 23 | Sep 25 | 123 | 5b |
| Delta | May 1 | Oct 7 | 159 | 6b |
| Denver Centennial Airport | May 5 | Oct 8 | 154 | 6a |
| Denver International Airport | May 5 | Oct 9 | 156 | 6a |
| Denver Water Department | Apr 30 | Oct 12 | 165 | 6a |
| Denver-Stapleton | May 4 | Oct 8 | 156 | 6a |
| Dinosaur | May 2 | Oct 14 | 161 | 6a |
| Dinosaur National Monument | May 12 | Oct 5 | 146 | 6a |
| Divide | Jun 1 | Sep 21 | 110 | 5b |
| Dove Creek | May 11 | Oct 12 | 152 | 6b |
| Durango | May 21 | Oct 2 | 134 | 6b |
| Durango La Plata County Airport | Jun 1 | Sep 27 | 116 | 6b |
| Eads | Apr 30 | Oct 13 | 165 | 6a |
| Eastonville | May 29 | Sep 21 | 114 | 5b |
| Elizabeth | May 16 | Oct 2 | 137 | 5b |
| Ellicott | May 6 | Oct 3 | 149 | 6a |
| Estes Park | May 30 | Sep 17 | 109 | 5a |
| Evergreen | May 23 | Sep 22 | 118 | 5b |
| Fairplay S Park Road | Jun 16 | Sep 9 | 83 | 5b |
| Flagler | May 5 | Oct 8 | 155 | 5b |
| Fleming | May 4 | Oct 11 | 157 | 5b |
| Fort Collins | May 2 | Oct 7 | 157 | 5b |
| Fort Collins 4 mi E | May 3 | Oct 6 | 154 | 5b |
| Fort Lewis | Jun 1 | Sep 27 | 116 | 6a |
| Fort Morgan | May 6 | Oct 6 | 153 | 5b |
| Fruita | Apr 27 | Oct 11 | 164 | 7a |
| Gateway | Apr 20 | Oct 21 | 182 | 6b |
| Genoa | May 8 | Oct 10 | 155 | 5b |
| Georgetown | May 30 | Sep 19 | 112 | 5a |
| Glade Park | May 21 | Sep 26 | 126 | 6b |
| Glenwood Springs | May 13 | Oct 3 | 142 | 6a |
| Grand Junction | Apr 14 | Oct 23 | 190 | 7a |
| Grand Junction 6 mi ESE | Apr 23 | Oct 20 | 179 | 7a |
| Grand Junction Walker Field | Apr 28 | Oct 16 | 171 | 7a |
| Grand Lake | Jun 13 | Sep 7 | 84 | 5a |
| Grant | Jun 15 | Sep 9 | 84 | 5b |
| Great Sand Dunes National Park & Preserve | May 21 | Oct 1 | 131 | 5a |
| Greeley Unc | May 2 | Oct 8 | 159 | 5b |
| Green Mount Dam | Jun 6 | Sep 14 | 98 | 5a |
| Gross Reservoir | May 24 | Sep 23 | 120 | 6a |
| Guffey | May 19 | Oct 2 | 134 | 6a |
| Hayden | Jun 1 | Sep 20 | 109 | 5a |
| Holly | May 1 | Oct 12 | 163 | 6a |
| Holyoke | May 11 | Oct 3 | 144 | 5b |
| Hugo | May 10 | Oct 2 | 143 | 5b |
| Idalia | May 4 | Oct 9 | 155 | 6a |
| Ignacio | May 23 | Sep 29 | 128 | 6a |
| Joes | May 3 | Oct 9 | 158 | 5b |
| John Martin Dam | Apr 24 | Oct 15 | 172 | 6a |
| Julesburg | May 7 | Oct 6 | 152 | 5b |
| Karval | May 9 | Oct 6 | 149 | 5b |
| Kassler | May 8 | Oct 3 | 147 | 5b |
| Kim 10 mi SSE | Apr 24 | Oct 18 | 175 | 6a |
| Kim 15 mi NNE | May 5 | Oct 9 | 156 | 6a |
| Kit Carson | May 10 | Oct 1 | 142 | 5b |
| Kit Carson 9 mi NNE | May 7 | Oct 6 | 151 | 5b |
| Kremmling | Jun 14 | Sep 5 | 80 | 5a |
| La Junta | Apr 26 | Oct 15 | 171 | 6a |
| La Junta 17 mi WSW | May 8 | Oct 4 | 148 | 6a |
| La Junta 20 mi S | Apr 27 | Oct 14 | 168 | 6a |
| La Junta Municipal Airport | Apr 24 | Oct 15 | 173 | 6a |
| Lake City | Jun 8 | Sep 17 | 101 | 5a |
| Lake City 1 mi NNE | Jun 9 | Sep 17 | 99 | 5a |
| Lake George | Jun 2 | Sep 19 | 108 | 5a |
| Lakewood | May 3 | Oct 7 | 155 | 6a |
| Lamar | Apr 30 | Oct 10 | 163 | 6a |
| Lamar Municipal Airport | May 2 | Oct 7 | 157 | 6a |
| Las Animas | Apr 29 | Oct 12 | 166 | 6a |
| Lemon Dam | May 28 | Sep 30 | 122 | 6a |
| Leroy | May 10 | Oct 6 | 147 | 5b |
| Limon Wsmo | May 21 | Sep 26 | 127 | 5b |
| Lindon | May 15 | Oct 2 | 139 | 5b |
| Longmont | May 7 | Oct 5 | 151 | 5b |
| Loveland | May 10 | Oct 1 | 142 | 5b |
| Manassa | May 28 | Sep 21 | 115 | 5a |
| Mancos | Jun 4 | Sep 24 | 111 | 6a |
| Marston Filter Plant | May 2 | Oct 11 | 160 | 6a |
| Massadona | May 10 | Oct 4 | 147 | 5b |
| Matheson | May 12 | Oct 2 | 141 | 5b |
| Maybell | Jun 16 | Sep 9 | 83 | 5b |
| Meeker | Jun 4 | Sep 16 | 104 | 5b |
| Meeker Airport | May 30 | Sep 22 | 117 | 5b |
| Mesa Verde National Park | May 9 | Oct 14 | 156 | 7a |
| Monte Vista | Jun 11 | Sep 13 | 92 | 5a |
| Montrose 11 mi ENE | May 20 | Oct 1 | 132 | 6b |
| Montrose No. 2 | Apr 28 | Oct 14 | 167 | 6b |
| Montrose Regional Airport | May 2 | Oct 8 | 157 | 6b |
| Monument | May 14 | Oct 1 | 138 | 5b |
| Monument 3 mi S | May 17 | Oct 1 | 136 | 5b |
| New Raymer | May 9 | Oct 4 | 146 | 5a |
| New Raymer 21 mi N | May 18 | Sep 29 | 133 | 5a |
| Northdale | Jun 3 | Sep 25 | 113 | 6b |
| Northglenn | May 2 | Oct 11 | 160 | 6a |
| Norwood | May 25 | Oct 1 | 128 | 6a |
| Norwood No. 2 | May 21 | Oct 1 | 131 | 6a |
| Nunn | May 13 | Sep 27 | 136 | 5a |
| Ordway 1 mi ENE | May 2 | Oct 8 | 159 | 5b |
| Ordway 21 mi N | May 3 | Oct 7 | 155 | 5b |
| Ouray | May 17 | Oct 1 | 137 | 5b |
| Ouray No. 2 | May 18 | Oct 4 | 139 | 5b |
| Palisade | Apr 17 | Oct 26 | 190 | 7a |
| Paonia | May 3 | Oct 12 | 159 | 6b |
| Paradox | May 11 | Oct 5 | 146 | 6b |
| Parker | May 9 | Oct 3 | 145 | 5b |
| Placerville | May 26 | Sep 29 | 125 | 5b |
| Pueblo | Apr 30 | Oct 9 | 162 | 6a |
| Pueblo Memorial Airport | Apr 30 | Oct 9 | 161 | 6a |
| Pueblo Reservoir | Apr 26 | Oct 13 | 166 | 6a |
| Ralston Reservoir | May 3 | Oct 14 | 161 | 6a |
| Rangely | May 15 | Oct 1 | 136 | 6a |
| Ridgway | Jun 11 | Sep 13 | 92 | 6a |
| Rifle | May 23 | Sep 25 | 124 | 6a |
| Rifle Garfield County Airport | May 11 | Oct 4 | 143 | 6a |
| Rio Grande Reservoir | Jun 15 | Sep 11 | 85 | 5a |
| Rocky Ford | May 1 | Oct 8 | 159 | 6a |
| Roxborough State Park | May 16 | Oct 1 | 136 | 5b |
| Rush | May 9 | Oct 4 | 146 | 5b |
| Rustic | Jun 5 | Sep 16 | 101 | 5b |
| Ruxton Park | Jun 3 | Sep 17 | 102 | 5b |
| Rye | May 5 | Oct 10 | 156 | 6a |
| Saguache | May 16 | Sep 28 | 135 | 5b |
| Salida | May 29 | Sep 20 | 112 | 5b |
| San Luis | May 31 | Sep 23 | 115 | 5b |
| Sedgwick | May 6 | Oct 7 | 152 | 5b |
| Seibert | May 4 | Oct 11 | 158 | 5b |
| Shaw | May 12 | Oct 4 | 143 | 5b |
| Sheep Mountain | May 27 | Sep 25 | 119 | 6a |
| Sheridan Lake | Apr 27 | Oct 15 | 170 | 6a |
| Sheridan Lake 4 mi E | Apr 28 | Oct 13 | 167 | 6a |
| Shoshone | May 1 | Oct 14 | 164 | 6a |
| Springfield Comanche | May 3 | Oct 10 | 158 | 6b |
| Steamboat Springs | Jun 9 | Sep 12 | 93 | 5b |
| Sterling | Apr 30 | Oct 9 | 161 | 5b |
| Stratton | May 6 | Oct 9 | 155 | 6a |
| Strontia Springs Dam | May 16 | Sep 29 | 132 | 5b |
| Tacony | May 5 | Oct 6 | 153 | 6a |
| Taylor Park | Jun 20 | Sep 8 | 80 | 5a |
| Trinidad | Apr 30 | Oct 15 | 167 | 6a |
| Trinidad Lake | May 11 | Oct 4 | 145 | 6a |
| Trinidad Perry Stokes Airport | May 4 | Oct 9 | 156 | 6a |
| Twin Lakes Reservoir | Jun 16 | Sep 10 | 85 | 5a |
| Uravan | Apr 26 | Oct 18 | 174 | 6b |
| Vail | Jun 21 | Sep 7 | 77 | 5b |
| Vallecito Dam | May 31 | Sep 26 | 119 | 6a |
| Vallecito Reservoir | May 18 | Oct 11 | 145 | 6a |
| Virginia Dale | May 31 | Sep 19 | 110 | 5b |
| Walsenburg | May 6 | Oct 4 | 149 | 6a |
| Walsh | Apr 30 | Oct 14 | 166 | 6b |
| Waterdale | May 12 | Oct 1 | 141 | 5b |
| Waverly | Jun 6 | Sep 15 | 100 | 4b |
| Westcliffe | Jun 11 | Sep 9 | 89 | 5b |
| Wheat Ridge | May 5 | Oct 5 | 151 | 6a |
| Wild Horse | May 4 | Oct 8 | 155 | 6a |
| Williams Fork Dam | Jun 12 | Sep 10 | 89 | 5b |
| Woodrow | May 15 | Oct 1 | 140 | 5b |
| Wray | May 7 | Oct 6 | 151 | 5b |
| Yampa | Jun 14 | Sep 11 | 89 | 5a |
| Yellow Jacket 2 mi W | May 17 | Oct 9 | 145 | 6b |
| Yellow Jacket 4 mi NE | May 15 | Oct 8 | 147 | 6b |
| Yuma | May 1 | Oct 12 | 164 | 5b |
Median dates from NOAA 1991–2020 climate normals. How to read them.