Iowa Frost Dates
The median last spring freeze and first fall freeze (32°F) at 150 NOAA stations in Iowa, 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 |
|---|---|---|---|---|---|
| Albia 3 Nne | 880 ft | April 24 | October 16 | 175 | Albia |
| Algona | 1,214 ft | April 30 | October 6 | 159 | Algona |
| Allerton | 1,090 ft | April 21 | October 19 | 181 | Corydon |
| Allison | 1,038 ft | April 27 | October 8 | 164 | Allison |
| Ames 5 Se | 870 ft | April 26 | October 12 | 169 | Cambridge |
| Ames 8 Wsw | 1,099 ft | April 23 | October 14 | 174 | Boone |
| Ames Muni AP | 930 ft | April 26 | October 8 | 165 | Ames |
| Anamosa 1 Wnw | 805 ft | May 1 | October 4 | 156 | Anamosa |
| Anamosa 3 Ssw | 906 ft | April 27 | October 13 | 169 | Anamosa |
| Ankeny | 975 ft | April 23 | October 15 | 175 | Ankeny |
| Atlantic 1 Ne | 1,152 ft | April 30 | October 2 | 155 | Atlantic |
| Audubon | 1,280 ft | May 2 | October 3 | 154 | Audubon |
| Battle Creek 3NE | 1,380 ft | May 1 | October 1 | 153 | Battle Creek |
| Beaconsfield | 1,215 ft | April 23 | October 17 | 177 | Mount Ayr |
| Bedford | 1,190 ft | April 24 | October 15 | 174 | Bedford |
| Belle Plaine | 810 ft | April 28 | October 10 | 165 | Belle Plaine |
| Bellevue L&d 12 | 603 ft | April 25 | October 16 | 174 | Bellevue |
| Bloomfield | 858 ft | April 16 | October 22 | 189 | Bloomfield |
| Boone | 1,035 ft | April 28 | October 12 | 167 | Boone |
| Britt 3E | 1,220 ft | April 29 | October 7 | 161 | Britt |
| Burlington 2S | 690 ft | April 18 | October 20 | 185 | Burlington |
| Burlington Muni AP | 692 ft | April 15 | October 20 | 188 | Burlington |
| Carroll | 1,240 ft | April 27 | October 10 | 166 | Carroll |
| Cascade | 814 ft | April 28 | October 10 | 165 | Cascade |
| Castana Exp Farm | 1,400 ft | April 25 | October 12 | 170 | Mapleton |
| Cedar Rapids #1 | 813 ft | April 28 | October 12 | 167 | Marion |
| Cedar Rapids Muni AP | 868 ft | April 27 | October 11 | 167 | Swisher |
| Centerville | 905 ft | April 28 | October 14 | 169 | Centerville |
| Chariton 1 E | 965 ft | May 5 | October 5 | 153 | Chariton |
| Charles City | 993 ft | April 30 | October 6 | 159 | Charles City |
| Cherokee | 1,210 ft | May 4 | October 4 | 153 | Cherokee |
| Clarinda | 980 ft | April 25 | October 11 | 169 | Clarinda |
| Clarion | 1,156 ft | April 30 | October 10 | 163 | Clarion |
| Clinton #1 | 585 ft | April 22 | October 16 | 177 | Camanche |
| Coggon | 903 ft | May 3 | October 7 | 157 | Coggon |
| Colo | 1,000 ft | April 24 | October 12 | 171 | Colo |
| Columbus Junction | 590 ft | April 26 | October 10 | 167 | Columbus Junction |
| Corning | 1,190 ft | April 27 | October 12 | 168 | Corning |
| Cresco 1 Ne | 1,255 ft | May 8 | October 1 | 146 | Cresco |
| Creston 2 Sw | 1,296 ft | April 28 | October 11 | 166 | Creston |
| Dakota City | 1,110 ft | April 26 | October 12 | 169 | Dakota City |
| Davenport | 754 ft | April 23 | October 15 | 175 | Eldridge |
| Davenport WFO | 750 ft | April 21 | October 17 | 179 | Eldridge |
| Decorah | 860 ft | May 3 | October 7 | 157 | Decorah |
| Denison | 1,401 ft | April 27 | October 11 | 167 | Denison |
| Des Moines 17 E | 921 ft | April 21 | October 15 | 177 | Prairie City |
| Des Moines Intl AP | 957 ft | April 18 | October 20 | 185 | Norwalk |
| Des Moines Wsfo-Johnston | 959 ft | April 19 | October 18 | 182 | Polk City |
| Donnellson | 705 ft | April 17 | October 22 | 188 | Donnellson |
| Dubuque L&d 11 | 620 ft | April 19 | October 21 | 185 | Dubuque |
| Dubuque Rgnl AP | 1,056 ft | April 28 | October 11 | 166 | |
| Eldora | 1,073 ft | April 27 | October 10 | 166 | Eldora |
| Elkader 6 Ssw | 788 ft | May 8 | October 1 | 146 | Elkader |
| Emmetsburg | 1,225 ft | April 27 | October 7 | 163 | Emmetsburg |
| Estherville 4E | 1,320 ft | May 2 | October 3 | 154 | Estherville |
| Estherville Muni AP | 1,317 ft | May 2 | September 30 | 151 | Estherville |
| Fairfield | 740 ft | April 27 | October 12 | 168 | Fairfield |
| Fayette | 1,145 ft | May 4 | October 4 | 153 | Fayette |
| Forest City 2 Nne | 1,280 ft | April 30 | October 7 | 160 | Forest City |
| Ft Dodge 5NNW | 1,115 ft | April 28 | October 8 | 163 | Badger |
| Ft Madison | 530 ft | April 12 | October 25 | 196 | Fort Madison |
| Glenwood 3SW | 980 ft | April 23 | October 11 | 171 | Glenwood |
| Greenfield | 1,316 ft | April 25 | October 12 | 170 | Greenfield |
| Grinnell 3 Sw | 905 ft | May 3 | October 6 | 156 | Grinnell |
| Grundy Ctr | 985 ft | April 29 | October 9 | 163 | Grundy Center |
| Guthrie Ctr | 1,065 ft | May 2 | October 3 | 154 | Guthrie Center |
| Guttenberg L&d 10 | 618 ft | April 21 | October 18 | 180 | Guttenberg |
| Hampton | 1,105 ft | April 29 | October 9 | 163 | Hampton |
| Harlan | 1,270 ft | April 27 | October 9 | 165 | Harlan |
| Hawarden | 1,190 ft | May 1 | October 4 | 156 | Hawarden |
| Holstein | 1,370 ft | April 30 | October 9 | 162 | Holstein |
| Humboldt Wtp | 1,100 ft | April 27 | October 9 | 165 | Humboldt |
| Ida Grove 5NW | 1,320 ft | April 27 | October 12 | 168 | Ida Grove |
| Independence #1 | 1,010 ft | April 30 | October 7 | 160 | Independence |
| Indianola 2W | 924 ft | April 24 | October 12 | 171 | Indianola |
| Iowa City | 640 ft | April 29 | October 9 | 163 | Iowa City |
| Iowa City Muni AP | 650 ft | April 21 | October 18 | 180 | University Heights |
| Iowa Falls | 1,055 ft | April 28 | October 10 | 165 | Iowa Falls |
| Jefferson | 1,055 ft | April 26 | October 9 | 166 | Jefferson |
| Keokuk Lock Dam 19 | 527 ft | April 10 | October 27 | 200 | Keokuk |
| Keosauqua | 629 ft | April 26 | October 13 | 170 | Keosauqua |
| Knoxville | 895 ft | April 20 | October 19 | 182 | Knoxville |
| Lake Park | 1,465 ft | April 30 | October 10 | 163 | Lake Park |
| Lamoni | 1,128 ft | April 17 | October 21 | 187 | Lamoni |
| Lamoni | 1,168 ft | April 16 | October 20 | 187 | Lamoni |
| Lamoni Muni AP | 1,131 ft | April 16 | October 21 | 188 | Lamoni |
| Le Claire L&d 14 | 577 ft | April 16 | October 25 | 192 | |
| Le Mars | 1,195 ft | April 30 | October 4 | 157 | Le Mars |
| Leon 6 Ese | 1,000 ft | April 30 | October 8 | 161 | Leon |
| Little Sioux 2 Nw | 1,025 ft | May 1 | October 3 | 155 | |
| Logan | 990 ft | April 29 | October 8 | 162 | Logan |
| Lowden | 738 ft | April 27 | October 10 | 166 | Lowden |
| Manchester #2 | 990 ft | May 3 | October 4 | 154 | Manchester |
| Mapleton No.2 | 1,200 ft | May 3 | October 1 | 151 | Mapleton |
| Maquoketa | 668 ft | April 25 | October 14 | 172 | Maquoketa |
| Marshalltown | 870 ft | April 28 | October 7 | 162 | Marshalltown |
| Marshalltown Muni AP | 974 ft | April 30 | October 6 | 159 | Marshalltown |
| Mason City | 1,105 ft | April 29 | October 7 | 161 | Mason City |
| Mason City Muni AP | 1,225 ft | May 3 | October 1 | 151 | Clear Lake |
| Milford 4 Nw | 1,402 ft | May 1 | October 6 | 158 | Okoboji |
| Mt Ayr | 1,140 ft | April 25 | October 12 | 170 | Mount Ayr |
| Mt Pleasant 1 Ssw | 730 ft | April 30 | October 10 | 163 | Mount Pleasant |
| Muscatine | 549 ft | April 24 | October 14 | 173 | Muscatine |
| Muscatine 2N | 680 ft | April 18 | October 22 | 187 | Muscatine |
| New Hampton | 1,148 ft | May 2 | October 5 | 156 | New Hampton |
| Newton | 960 ft | April 22 | October 17 | 178 | Newton |
| Northwood | 1,190 ft | May 4 | October 4 | 153 | Northwood |
| Oakland | 1,260 ft | April 23 | October 14 | 174 | Oakland |
| Oelwein 1E | 1,165 ft | April 27 | October 13 | 169 | Oelwein |
| Oelwein 2 S | 1,010 ft | April 30 | October 9 | 162 | Oelwein |
| Onawa 3NW | 1,060 ft | May 1 | October 3 | 155 | Onawa |
| Osage | 1,170 ft | April 30 | October 9 | 162 | Osage |
| Osceola | 1,028 ft | April 29 | October 9 | 163 | Osceola |
| Oskaloosa | 830 ft | April 21 | October 16 | 178 | Oskaloosa |
| Ottumwa Industrial AP | 842 ft | April 23 | October 14 | 174 | Ottumwa |
| Perry | 950 ft | April 25 | October 10 | 168 | Perry |
| Pocahontas | 1,212 ft | April 26 | October 7 | 164 | Pocahontas |
| Postville | 1,165 ft | May 1 | October 3 | 155 | Postville |
| Primghar | 1,520 ft | April 29 | October 10 | 164 | Primghar |
| Rathbun Dam | 965 ft | April 18 | October 23 | 188 | Moravia |
| Red Oak | 1,040 ft | April 24 | October 13 | 172 | Red Oak |
| Rock Rapids | 1,350 ft | May 1 | October 4 | 156 | Rock Rapids |
| Rockwell City | 1,214 ft | April 26 | October 10 | 167 | Rockwell City |
| Sac City | 1,210 ft | April 30 | October 6 | 159 | Sac City |
| Sanborn | 1,551 ft | May 1 | October 7 | 159 | Sanborn |
| Sheldon | 1,420 ft | May 5 | September 28 | 146 | Sheldon |
| Shenandoah | 999 ft | April 20 | October 17 | 180 | Shenandoah |
| Sibley | 1,529 ft | May 5 | October 3 | 151 | Sibley |
| Sidney 1SSE | 1,140 ft | April 19 | October 19 | 183 | Sidney |
| Sigourney | 732 ft | April 24 | October 15 | 174 | Sigourney |
| Sioux City Ang | 1,100 ft | April 29 | October 7 | 161 | Sergeant Bluff |
| Sioux City Gateway AP | 1,095 ft | April 29 | October 5 | 159 | Sergeant Bluff |
| Sioux Ctr 2 Se | 1,360 ft | April 30 | October 3 | 156 | Sioux Center |
| Sioux Rapids 4 E | 1,420 ft | April 30 | October 5 | 158 | Sioux Rapids |
| Spencer 1 N | 1,326 ft | May 1 | October 3 | 155 | Spencer |
| Spencer Muni AP | 1,338 ft | May 2 | October 2 | 153 | Spencer |
| Spirit Lake | 1,420 ft | April 28 | October 11 | 166 | Spirit Lake |
| Stanley | 1,114 ft | May 4 | October 1 | 150 | Hazleton |
| Storm Lake | 1,442 ft | April 25 | October 13 | 171 | Storm Lake |
| Swea City 5N | 1,180 ft | May 4 | October 1 | 150 | Swea City |
| Tipton | 820 ft | April 21 | October 15 | 177 | Tipton |
| Toledo 3N | 935 ft | April 30 | October 9 | 162 | Toledo |
| Tripoli | 1,055 ft | April 29 | October 9 | 163 | Tripoli |
| Vinton | 850 ft | May 3 | October 3 | 153 | Vinton |
| Washington | 687 ft | April 28 | October 11 | 166 | Washington |
| Waterloo Muni AP | 868 ft | April 27 | October 10 | 166 | Cedar Falls |
| Waukon | 1,275 ft | May 2 | October 11 | 162 | Waukon |
| Webster City | 1,072 ft | May 3 | October 2 | 152 | Webster City |
| Williamsburg 1E | 780 ft | April 28 | October 9 | 164 | Williamsburg |
| Winterset 1S | 1,100 ft | April 30 | October 3 | 156 | Buffalo (historical) |
Sources
NOAA NCEI U.S. Climate Normals, 1991-2020, annual and seasonal freeze probabilities. Public domain.