Frost dates in Wisconsin

Across Wisconsin, the typical last spring frost is around May 4 and the first fall frost around Oct 7. Your own dates depend on where you are in the state; find your county below.

Most of the state's last spring frosts fall between Apr 26 and May 19, and its first fall frosts between Sep 28 and Oct 18.

These are the dates with a 50% chance of a 32°F frost on or after (spring) or on or before (fall), so plan tender crops a week or two after the spring date and keep row cover handy. For dates at your exact ZIP code, use the zone and frost date lookup; for what to plant when, see the planting guide by frost date.

Hardiness zones in Wisconsin: zone 4a, zone 4b, zone 5a, zone 5b, zone 6a

Frost dates by county in Wisconsin

CountyLast spring frostFirst fall frostGrowing season
AdamsMay 9Oct 3About 147 days
AshlandMay 22Sep 27About 128 days
BarronMay 8Oct 2About 147 days
BayfieldMay 23Oct 2About 132 days
BrownMay 6Oct 9About 156 days
BuffaloApr 28Oct 14About 169 days
BurnettMay 11Oct 1About 143 days
CalumetMay 6Oct 6About 153 days
ChippewaMay 5Oct 3About 151 days
ClarkMay 11Oct 1About 143 days
ColumbiaMay 1Oct 9About 161 days
CrawfordMay 3Oct 7About 157 days
DaneMay 1Oct 10About 162 days
DodgeMay 1Oct 10About 162 days
DoorMay 14Oct 18About 157 days
DouglasMay 24Sep 26About 125 days
DunnMay 9Oct 1About 145 days
Eau ClaireMay 7Oct 2About 148 days
FlorenceMay 24Sep 30About 129 days
Fond du LacMay 1Oct 12About 164 days
ForestMay 19Sep 29About 133 days
GrantApr 27Oct 12About 168 days
GreenApr 27Oct 14About 170 days
Green LakeMay 6Oct 2About 149 days
IowaMay 3Oct 7About 157 days
IronMay 24Sep 28About 127 days
JacksonMay 9Oct 1About 145 days
JeffersonApr 30Oct 12About 165 days
JuneauMay 2Oct 4About 155 days
KenoshaApr 28Oct 19About 174 days
KewauneeMay 1Oct 18About 170 days
La CrosseApr 27Oct 13About 169 days
LafayetteApr 30Oct 13About 166 days
LangladeMay 14Sep 30About 139 days
LincolnMay 11Sep 30About 142 days
ManitowocMay 1Oct 14About 166 days
MarathonMay 6Oct 4About 151 days
MarinetteMay 22Oct 1About 132 days
MarquetteMay 3Oct 5About 155 days
MenomineeMay 13Oct 2About 142 days
MilwaukeeApr 26Oct 18About 175 days
MonroeMay 6Oct 3About 150 days
OcontoMay 14Oct 6About 145 days
OneidaMay 23Oct 3About 133 days
OutagamieMay 4Oct 6About 155 days
OzaukeeApr 27Oct 24About 180 days
PepinMay 1Oct 10About 162 days
PierceMay 11Oct 2About 144 days
PolkMay 6Oct 4About 151 days
PortageMay 4Oct 7About 156 days
PriceMay 23Sep 23About 123 days
RacineMay 5Oct 10About 158 days
RichlandMay 5Oct 6About 154 days
RockApr 29Oct 12About 166 days
RuskMay 9Sep 29About 143 days
SaukMay 2Oct 7About 158 days
SawyerMay 19Sep 27About 131 days
ShawanoMay 13Oct 1About 141 days
SheboyganMay 3Oct 16About 166 days
St. CroixMay 6Oct 2About 149 days
TaylorMay 11Oct 1About 143 days
TrempealeauMay 9Oct 2About 146 days
VernonApr 27Oct 14About 170 days
VilasMay 25Sep 24About 122 days
WalworthApr 28Oct 14About 169 days
WashburnMay 14Sep 28About 137 days
WashingtonMay 1Oct 12About 164 days
WaukeshaMay 1Oct 13About 165 days
WaupacaMay 6Oct 6About 153 days
WausharaMay 8Oct 6About 151 days
WinnebagoApr 30Oct 13About 166 days
WoodMay 6Oct 3About 150 days

Source: NOAA NCEI U.S. Climate Normals 1991–2020, 50% probability of 32°F, from the weather station nearest each ZIP code; each county shows the middle value across its ZIP codes. Hills, valleys and cities can run a week or more earlier or later.

Frost dates for other states