NOAA 1991–2020 freeze normals
Frost Dates in Wisconsin
Last and first frost at the 175 NOAA stations behind this site's Wisconsin pages.
At the middle station of the 175 in Wisconsin where a freeze comes every year, the last spring frost (50%) is May 5 and the first fall frost October 8, a freeze-free season of 155 days. The last frost is earliest at Milwaukee (Milwaukee Mitchell Airport, WI, April 19) and latest at Ladysmith (Ladysmith 3W, WI, May 27), 38 days apart. The season runs from 117 days at Ladysmith to 192 at Milwaukee.
126 of these stations were also in NOAA's previous normals, for 1981–2010. Between the two, the median station's freeze-free season grew 6 days longer, with the last spring frost 1 day earlier and the first fall frost 4 days later; the season lengthened at 105 stations and shortened at 18. The two periods share twenty years, so the change reflects mostly 2011–2020 against 1981–1990.
Wisconsin places by frost date
| Place | ZIP | Last frost | First frost | Season | Winters with 32°F |
|---|---|---|---|---|---|
| Milwaukee | 53215 | April 26 | October 22 | 177 d | 100% |
| Madison | 53711 | May 1 | October 9 | 161 d | 100% |
| La Crosse | 54601 | April 27 | October 13 | 167 d | 100% |
| De Pere | 54115 | April 30 | October 9 | 161 d | 100% |
| Beloit | 53511 | May 1 | October 12 | 162 d | 100% |
| Madison | 53704 | May 1 | October 10 | 160 d | 100% |
| Neenah | 54956 | May 4 | October 6 | 154 d | 100% |
| Milwaukee | 53209 | April 26 | October 18 | 173 d | 100% |
| Sheboygan | 53081 | April 25 | October 23 | 179 d | 100% |
| Eau Claire | 54703 | May 8 | October 4 | 149 d | 100% |
| Eau Claire | 54701 | April 24 | October 14 | 170 d | 100% |
| Fond Du Lac | 54935 | April 27 | October 19 | 174 d | 100% |
| Green Bay | 54313 | May 7 | October 9 | 154 d | 100% |
| Manitowoc | 54220 | April 30 | October 20 | 171 d | 100% |
| Menomonee Falls | 53051 | May 6 | October 8 | 154 d | 100% |
| Milwaukee | 53221 | April 19 | October 29 | 192 d | 100% |
| Oconomowoc | 53066 | April 30 | October 12 | 164 d | 100% |
| Oshkosh | 54901 | April 24 | October 20 | 178 d | 100% |
| Oak Creek | 53154 | April 22 | October 26 | 184 d | 100% |
| Franklin | 53132 | May 3 | October 14 | 162 d | 100% |
| Racine | 53402 | April 24 | October 24 | 180 d | 100% |
| Waukesha | 53188 | May 1 | October 13 | 162 d | 100% |
| Hudson | 54016 | April 22 | October 19 | 178 d | 100% |
| Madison | 53719 | April 28 | October 15 | 169 d | 100% |
| Kenosha | 53142 | April 19 | October 26 | 189 d | 100% |
| Wausau | 54401 | May 6 | October 4 | 150 d | 100% |
| Superior | 54880 | May 6 | October 9 | 154 d | 100% |
| Janesville | 53546 | April 26 | October 15 | 170 d | 100% |
| Burlington | 53105 | May 5 | October 9 | 156 d | 100% |
| Stevens Point | 54481 | May 4 | October 7 | 155 d | 100% |
| Racine | 53405 | April 20 | October 24 | 184 d | 100% |
| West Bend | 53095 | May 1 | October 12 | 161 d | 100% |
| Wisconsin Rapids | 54494 | May 9 | September 30 | 142 d | 100% |
| Pewaukee | 53072 | April 30 | October 14 | 164 d | 100% |
| Kenosha | 53144 | April 28 | October 19 | 174 d | 100% |
| Marshfield | 54449 | May 5 | October 5 | 152 d | 100% |
| Menomonie | 54751 | May 9 | October 1 | 143 d | 100% |
| Onalaska | 54650 | April 23 | October 17 | 177 d | 100% |
| River Falls | 54022 | May 11 | October 1 | 143 d | 100% |
| Hartford | 53027 | May 8 | October 3 | 148 d | 100% |
| Beaver Dam | 53916 | May 2 | October 9 | 157 d | 100% |
| Oshkosh | 54902 | April 30 | October 13 | 165 d | 100% |
| Fond Du Lac | 54937 | May 1 | October 10 | 160 d | 100% |
| Baraboo | 53913 | May 5 | October 5 | 152 d | 100% |
| Mequon | 53092 | April 23 | October 24 | 182 d | 100% |
| Rhinelander | 54501 | May 26 | September 23 | 120 d | 100% |
| Whitewater | 53190 | May 2 | October 9 | 157 d | 100% |
| Sussex | 53089 | April 30 | October 16 | 167 d | 100% |
| New Richmond | 54017 | May 6 | October 2 | 148 d | 100% |
| Stoughton | 53589 | April 30 | October 11 | 163 d | 100% |
| Merrill | 54452 | May 11 | September 30 | 139 d | 100% |
| Waterford | 53185 | May 5 | October 10 | 156 d | 100% |
| Elkhorn | 53121 | April 28 | October 14 | 168 d | 100% |
| Fort Atkinson | 53538 | April 28 | October 13 | 166 d | 100% |
| Lake Geneva | 53147 | April 25 | October 21 | 179 d | 100% |
| Watertown | 53094 | April 28 | October 12 | 167 d | 100% |
| Sparta | 54656 | May 9 | October 1 | 144 d | 100% |
| Sturgeon Bay | 54235 | May 8 | October 13 | 157 d | 100% |
| Shawano | 54166 | May 9 | October 2 | 144 d | 100% |
| Deforest | 53532 | May 4 | October 6 | 154 d | 100% |
| Plymouth | 53073 | May 3 | October 10 | 159 d | 100% |
| Tomah | 54660 | May 6 | October 3 | 148 d | 100% |
| Rice Lake | 54868 | May 8 | October 2 | 145 d | 100% |
| Platteville | 53818 | April 30 | October 13 | 166 d | 100% |
| Marinette | 54143 | May 4 | October 11 | 160 d | 100% |
| Waupaca | 54981 | May 8 | October 6 | 151 d | 100% |
| Monroe | 53566 | April 27 | October 14 | 170 d | 100% |
| Portage | 53901 | April 28 | October 10 | 164 d | 100% |
| Reedsburg | 53959 | May 2 | October 7 | 156 d | 100% |
| New London | 54961 | May 4 | October 6 | 153 d | 100% |
| Two Rivers | 54241 | April 27 | October 21 | 175 d | 100% |
| Waupun | 53963 | May 1 | October 11 | 163 d | 100% |
| Port Washington | 53074 | April 27 | October 22 | 176 d | 100% |
| Hayward | 54843 | May 23 | September 22 | 122 d | 100% |
| Antigo | 54409 | May 14 | September 30 | 139 d | 100% |
| Ashland | 54806 | May 20 | October 2 | 133 d | 100% |
| Sheboygan Falls | 53085 | May 5 | October 8 | 154 d | 100% |
| Wisconsin Dells | 53965 | May 8 | October 3 | 146 d | 100% |
| Black River Falls | 54615 | May 9 | October 1 | 143 d | 100% |
| Medford | 54451 | May 11 | October 1 | 141 d | 100% |
| Ripon | 54971 | May 1 | October 11 | 163 d | 100% |
| Mount Horeb | 53572 | May 7 | October 1 | 148 d | 100% |
| Richland Center | 53581 | May 5 | October 6 | 154 d | 100% |
| Jackson | 53037 | April 30 | October 15 | 167 d | 100% |
| Jefferson | 53549 | April 25 | October 18 | 173 d | 100% |
| Tomahawk | 54487 | May 10 | October 4 | 146 d | 100% |
| Union Grove | 53182 | May 5 | October 8 | 156 d | 100% |
| Lake Mills | 53551 | April 29 | October 14 | 167 d | 100% |
| Salem | 53168 | April 30 | October 15 | 167 d | 100% |
| Slinger | 53086 | May 5 | October 5 | 152 d | 100% |
| Genoa City | 53128 | April 30 | October 13 | 164 d | 100% |
| Clintonville | 54929 | May 4 | October 6 | 154 d | 100% |
| Columbus | 53925 | April 30 | October 9 | 163 d | 100% |
| Berlin | 54923 | May 1 | October 8 | 158 d | 100% |
| Viroqua | 54665 | May 7 | October 2 | 148 d | 100% |
| Lodi | 53555 | May 1 | October 10 | 162 d | 100% |
| Eagle River | 54521 | May 25 | September 24 | 121 d | 100% |
| Nekoosa | 54457 | May 8 | October 1 | 145 d | 100% |
| Mauston | 53948 | May 2 | October 7 | 158 d | 100% |
| Amery | 54001 | May 5 | October 4 | 151 d | 100% |
| Chilton | 53014 | May 1 | October 14 | 162 d | 100% |
| Luxemburg | 54217 | May 1 | October 18 | 168 d | 100% |
| Osceola | 54020 | May 4 | October 8 | 156 d | 100% |
| Prairie Du Chien | 53821 | April 28 | October 12 | 166 d | 100% |
| Seymour | 54165 | May 1 | October 11 | 160 d | 100% |
| Bloomer | 54724 | May 5 | October 3 | 151 d | 100% |
| Oconto | 54153 | May 9 | October 6 | 150 d | 100% |
| Dodgeville | 53533 | May 3 | October 7 | 157 d | 100% |
| Mondovi | 54755 | May 10 | October 2 | 144 d | 100% |
| Mayville | 53050 | May 1 | October 10 | 158 d | 100% |
| Dousman | 53118 | May 3 | October 9 | 157 d | 100% |
| Ellsworth | 54011 | May 13 | September 29 | 139 d | 100% |
| Wautoma | 54982 | May 10 | October 3 | 146 d | 100% |
| Brodhead | 53520 | April 29 | October 12 | 165 d | 100% |
| Stanley | 54768 | May 7 | October 3 | 147 d | 100% |
| Prairie Du Sac | 53578 | May 4 | October 6 | 155 d | 100% |
| Montello | 53949 | May 3 | October 5 | 153 d | 100% |
| Lancaster | 53813 | April 27 | October 11 | 166 d | 100% |
| Spooner | 54801 | May 14 | September 28 | 135 d | 100% |
| Denmark | 54208 | May 6 | October 12 | 158 d | 100% |
| Peshtigo | 54157 | May 11 | October 5 | 145 d | 100% |
| Neillsville | 54456 | May 10 | October 1 | 144 d | 100% |
| Ladysmith | 54848 | May 27 | September 22 | 117 d | 100% |
| Crivitz | 54114 | May 26 | September 22 | 118 d | 100% |
| Arcadia | 54612 | May 5 | October 5 | 152 d | 100% |
| Brillion | 54110 | May 6 | October 6 | 151 d | 100% |
| Minocqua | 54548 | May 23 | September 27 | 127 d | 100% |
| Boscobel | 53805 | May 3 | October 7 | 155 d | 100% |
| Stratford | 54484 | May 5 | October 5 | 150 d | 100% |
| Cumberland | 54829 | May 5 | October 4 | 152 d | 100% |
| Algoma | 54201 | May 6 | October 17 | 163 d | 100% |
| Oostburg | 53070 | May 3 | October 16 | 165 d | 100% |
| Saukville | 53080 | May 5 | October 11 | 158 d | 100% |
| Fall Creek | 54742 | May 7 | October 1 | 146 d | 100% |
| Phillips | 54555 | May 23 | September 23 | 124 d | 100% |
| Darlington | 53530 | May 3 | October 4 | 153 d | 100% |
| Hillsboro | 54634 | May 12 | September 29 | 138 d | 100% |
| Fredonia | 53021 | May 5 | October 12 | 159 d | 100% |
| Friendship | 53934 | May 9 | October 3 | 147 d | 100% |
| Galesville | 54630 | April 29 | October 11 | 165 d | 100% |
| Webster | 54893 | May 11 | September 30 | 138 d | 100% |
| Markesan | 53946 | May 8 | October 2 | 144 d | 100% |
| Park Falls | 54552 | May 15 | September 28 | 134 d | 100% |
| Durand | 54736 | May 1 | October 10 | 162 d | 100% |
| Crandon | 54520 | May 19 | September 29 | 131 d | 100% |
| Spring Green | 53588 | April 30 | October 9 | 161 d | 100% |
| Cashton | 54619 | April 27 | October 14 | 170 d | 100% |
| South Range | 54874 | May 18 | October 3 | 135 d | 100% |
| Necedah | 54646 | May 17 | September 25 | 131 d | 100% |
| Colby | 54421 | May 13 | September 26 | 136 d | 100% |
| Frederic | 54837 | May 6 | October 4 | 149 d | 100% |
| Iola | 54945 | May 6 | October 5 | 150 d | 100% |
| Gillett | 54124 | May 14 | October 1 | 139 d | 100% |
| Washburn | 54891 | May 23 | October 2 | 131 d | 100% |
| Birnamwood | 54414 | May 13 | September 30 | 141 d | 100% |
| Solon Springs | 54873 | May 12 | October 2 | 142 d | 100% |
| Florence | 54121 | May 24 | September 25 | 121 d | 100% |
| Boyceville | 54725 | May 10 | September 29 | 140 d | 100% |
| Elroy | 53929 | May 5 | October 4 | 153 d | 100% |
| Cornell | 54732 | May 5 | October 2 | 149 d | 100% |
| Bayfield | 54814 | May 20 | October 8 | 141 d | 100% |
| Wausaukee | 54177 | May 22 | September 27 | 126 d | 100% |
| Hurley | 54534 | May 24 | September 28 | 128 d | 100% |
| Bruce | 54819 | May 9 | September 29 | 140 d | 100% |
| North Freedom | 53951 | April 24 | October 20 | 178 d | 100% |
| Fountain City | 54629 | April 23 | October 21 | 180 d | 100% |
| Stoddard | 54658 | April 22 | October 17 | 178 d | 100% |
| Iron River | 54847 | May 24 | September 26 | 124 d | 100% |
| Iron Ridge | 53035 | April 28 | October 10 | 164 d | 100% |
| Malone | 53049 | May 1 | October 12 | 162 d | 100% |
| Cambria | 53923 | May 6 | October 2 | 150 d | 100% |
| Minong | 54859 | May 10 | October 4 | 144 d | 100% |
| Saint Germain | 54558 | May 19 | October 3 | 136 d | 100% |
| Camp Douglas | 54618 | May 1 | October 3 | 157 d | 100% |
| Sister Bay | 54234 | May 14 | October 18 | 155 d | 100% |
50% dates from NOAA NCEI U.S. Climate Normals 1991–2020, one row per station; a state page is published when at least 5 stations stand behind its pages. Where a freeze comes in fewer than nine winters in ten, the dates describe the winters that have one.