Frost Dates in Iowa

Below is the likelihood of experiencing 32°F on or before the given date in fall and on or after the given date in spring.

Oak with frost on leavesLinks to high-population counties are below, and all counties are listed alphabetically.   
Early = only 10% of all freeze dates occurred before this day.
Average = the average freeze date for this location.
Late = only 10% of all freeze dates occured after this day.

This information is based on weather data collected from 1950-2021.*

Date of First Freeze in Fall  |  Date of Last Freeze in Spring

Quick Links to Populus Counties

Polk CountyFirst Fall FreezeLast Spring FreezeDes Moines, West Des Moines, Ankeny, Urbandale, Johnston, Altoona, Clive
Linn CountyFirst Fall FreezeLast Spring FreezeCedar Rapids, Marion
Scott CountyFirst Fall FreezeLast Spring FreezeDavenport, Bettendorf
Johnson CountyFirst Fall FreezeLast Spring FreezeIowa City, Coralville, North Liberty
Black Hawk CountyFirst Fall FreezeLast Spring FreezeWaterloo, Cedar Falls
Woodbury CountyFirst Fall FreezeLast Spring FreezeSioux City
Dallas CountyFirst Fall FreezeLast Spring FreezeWaukee, West Des Moines, Urbandale, Clive, Grimes
Dubuque CountyFirst Fall FreezeLast Spring FreezeDubuque
Story CountyFirst Fall FreezeLast Spring FreezeAmes
Pottawattamie CountyFirst Fall FreezeLast Spring FreezeCouncil Bluffs
Warren CountyFirst Fall FreezeLast Spring FreezeIndianola, Norwalk
Clinton CountyFirst Fall FreezeLast Spring FreezeClinton
Muscatine CountyFirst Fall FreezeLast Spring FreezeMuscatine
Cerro Gordo CountyFirst Fall FreezeLast Spring FreezeMason City
Marshall CountyFirst Fall FreezeLast Spring FreezeMarshalltown

Date of First Freeze in Fall

Listed alphabetically by county. 
Early = the first freeze date occurred before this day in 10% of years.
Average = the average first freeze date for this location.
Late = the first freeze date occurred after this day in 10% of years.

CountyEarly First Fall Freeze (32°F)Average First Fall Freeze (32°F)Late First Fall Freeze (32°F)
AdairSep 26Oct 07Oct 23
AdamsSep 26Oct 08Oct 25
AllamakeeSep 26Oct 07Oct 21
AppanooseSep 30Oct 14Oct 28
AudubonSep 21Oct 03Oct 15
BentonSep 22Oct 05Oct 17
Black HawkSep 22Oct 05Oct 18
BooneSep 23Oct 06Oct 20
BremerSep 22Oct 05Oct 19
BuchananSep 20Oct 03Oct 14
Buena VistaSep 23Oct 06Oct 23
ButlerSep 27Oct 07Oct 22
CalhounSep 27Oct 07Oct 20
CarrollSep 21Oct 03Oct 19
CassSep 21Oct 05Oct 18
CedarSep 24Oct 09Oct 22
Cerro GordoSep 22Oct 05Oct 19
CherokeeSep 19Oct 02Oct 15
ChickasawSep 22Oct 05Oct 18
ClarkeSep 26Oct 10Oct 25
ClaySep 22Oct 05Oct 18
ClaytonSep 21Oct 03Oct 15
ClintonOct 01Oct 14Oct 28
CrawfordSep 23Oct 06Oct 20
DallasSep 22Oct 06Oct 18
DavisOct 01Oct 15Oct 28
DecaturSep 29Oct 12Oct 29
DelawareSep 21Oct 03Oct 14
Des MoinesOct 03Oct 19Nov 03
DickinsonSep 22Oct 04Oct 19
DubuqueSep 26Oct 09Oct 22
EmmetSep 22Oct 04Oct 20
FayetteSep 20Oct 02Oct 15
FloydSep 27Oct 07Oct 21
FranklinSep 21Oct 05Oct 19
FremontSep 30Oct 13Oct 27
GreeneSep 24Oct 06Oct 21
GrundySep 23Oct 06Oct 20
GuthrieSep 21Oct 04Oct 16
HamiltonSep 21Oct 05Oct 16
HancockSep 22Oct 05Oct 18
HardinSep 23Oct 06Oct 19
HarrisonSep 26Apr 16Oct 20
HenryOct 01Oct 15Oct 29
HowardSep 20Oct 02Oct 13
HumboldtSep 23Oct 07Oct 23
IdaSep 21Oct 04Oct 15
IowaSep 23Oct 07Oct 19
JacksonSep 27Oct 09Oct 22
JasperSep 26Oct 09Oct 25
JeffersonSep 30Oct 13Oct 28
JohnsonSep 27Oct 09Oct 22
JonesSep 22Oct 05Oct 17
KeokukSep 30Oct 13Oct 28
KossuthSep 25Oct 06Oct 18
LeeOct 06Oct 19Nov 02
LinnSep 25Oct 06Oct 18
LouisaOct 01Oct 14Oct 28
LucasSep 27Oct 08Oct 21
LyonSep 19Sep 30Oct 14
MadisonSep 23Oct 07Oct 21
MahaskaSep 27Oct 11Oct 27
MarionSep 29Oct 11Oct 28
MarshallSep 26Oct 08Oct 21
MillsSep 28Oct 10Oct 27
MitchellSep 23Oct 06Oct 19
MononaSep 26Oct 07Oct 22
MonroeSep 30Oct 14Oct 28
MontgomerySep 23Oct 08Oct 24
MuscatineSep 30Oct 14Oct 28
O'BrienSep 22Oct 04Oct 16
OsceolaSep 21Oct 03Oct 15
PageSep 27Oct 09Oct 26
Palo AltoSep 25Oct 07Oct 23
PlymouthSep 20Oct 02Oct 16
PocahontasSep 23Oct 06Oct 20
PolkSep 26Oct 10Oct 26
PottawattamieSep 26Oct 08Oct 26
PoweshiekSep 25Oct 07Oct 21
RinggoldSep 27Oct 11Oct 27
SacSep 24Oct 07Oct 24
ScottOct 05Oct 19Nov 02
ShelbySep 22Oct 06Oct 18
SiouxSep 19Oct 01Oct 14
StorySep 26Oct 07Oct 21
TamaSep 22Oct 08Oct 18
TaylorSep 27Oct 10Oct 27
UnionSep 27Oct 10Oct 28
Van BurenOct 01Oct 15Oct 28
WapelloOct 01Oct 15Oct 28
WarrenSep 27Oct 10Oct 23
WashingtonSep 28Oct 12Oct 27
WayneSep 30Oct 12Oct 27
WebsterSep 23Oct 07Oct 20
WinnebagoSep 22Oct 04Oct 15
WinneshiekSep 21Oct 03Oct 15
WoodburySep 21Oct 04Oct 16
WorthSep 23Oct 05Oct 18
WrightSep 21Oct 03Oct 15

Date of Last Freeze in Spring

Listed alphabetically by county. 
Early = the last freeze date was before this date in 10% of years.
Average = the average last freeze date for this location.
Late = the last freeze date occurred after this day in 10% of years.

CountyEarly Last Spring Freeze Date (32°F)Average Last Spring Freeze Date (32°F)Late Last Spring Freeze Date (32°F)
AdairApr 11Apr 25May 10
AdamsApr 11Apr 24May 08
AllamakeeApr 09Apr 26May 11
AppanooseApr 05Apr 17May 03
AudubonApr 13Apr 27May 11
BentonApr 13Apr 25May 08
Black HawkApr 14Apr 28May 11
BooneApr 13Apr 26May 08
BremerApr 13Apr 28May 11
BuchananApr 16Apr 29May 14
Buena VistaApr 12Apr 28May 11
ButlerApr 13Apr 27May 10
CalhounApr 13Apr 26May 08
CarrollApr 13Apr 27May 09
CassApr 11Apr 26May 11
CedarApr 09Apr 23May 06
Cerro GordoApr 15Apr 29May 11
CherokeeApr 16May 01May 14
ChickasawApr 16Apr 29May 11
ClarkeApr 09Apr 23May 08
ClayApr 12Apr 28May 11
ClaytonApr 16Apr 29May 12
ClintonApr 06Apr 18May 02
CrawfordApr 09Apr 25May 09
DallasApr 10Apr 25May 08
DavisApr 03Apr 15Apr 29
DecaturApr 07Apr 20May 03
DelawareApr 16May 01May 15
Des MoinesApr 03Apr 15Apr 28
DickinsonApr 14Apr 28May 10
DubuqueApr 10Apr 23May 06
EmmetApr 15Apr 28May 10
FayetteApr 18May 01May 15
FloydApr 13Apr 27May 10
FranklinApr 17Apr 28May 11
FremontApr 05Apr 17Apr 30
GreeneApr 13Apr 26May 09
GrundyApr 16Apr 27May 10
GuthrieApr 13Apr 27May 09
HamiltonApr 13Apr 29May 13
HancockApr 14Apr 28May 11
HardinApr 13Apr 26May 09
HarrisonApr 11Apr 24May 07
HenryApr 05Apr 17Apr 30
HowardApr 21May 03May 15
HumboldtApr 11Apr 27May 09
IdaApr 14Apr 29May 12
IowaApr 10Apr 24May 06
JacksonApr 10Apr 25May 08
JasperApr 09Apr 22May 05
JeffersonApr 05Apr 17May 01
JohnsonApr 09Apr 22May 06
JonesApr 16Apr 29May 13
KeokukApr 07Apr 19May 03
KossuthApr 14Apr 28May 11
LeeApr 04Apr 13Apr 25
LinnApr 14Apr 26May 09
LouisaApr 05Apr 17May 02
LucasApr 10Apr 24May 07
LyonApr 18May 01May 14
MadisonApr 10Apr 25May 09
MahaskaApr 08Apr 20May 03
MarionApr 06Apr 20May 03
MarshallApr 13Apr 24May 08
MillsApr 08Apr 22May 08
MitchellApr 16Apr 30May 11
MononaApr 09Apr 26May 10
MonroeApr 06Apr 19May 03
MontgomeryApr 09Apr 24May 09
MuscatineApr 05Apr 17Apr 30
O'BrienApr 15Apr 29May 14
OsceolaApr 17Apr 30May 14
PageApr 08Apr 22May 06
Palo AltoApr 14Apr 27May 10
PlymouthApr 15Apr 28May 12
PocahontasApr 10Apr 26May 09
PolkApr 09Apr 22May 04
PottawattamieApr 09Apr 24May 08
PoweshiekApr 13Apr 26May 09
RinggoldApr 08Apr 21May 06
SacApr 09Apr 26May 09
ScottApr 05Apr 15Apr 30
ShelbyApr 09Apr 24May 09
SiouxApr 18May 01May 13
StoryApr 13Apr 24May 06
TamaApr 14Apr 27May 10
TaylorApr 09Apr 22May 06
UnionApr 09Apr 23May 07
Van BurenApr 05Apr 18May 01
WapelloApr 05Apr 16Apr 30
WarrenApr 09Apr 23May 06
WashingtonApr 07Apr 20May 04
WayneApr 07Apr 20May 03
WebsterApr 13Apr 26May 09
WinnebagoApr 14Apr 28May 10
WinneshiekApr 18May 02May 18
WoodburyApr 09Apr 26May 10
WorthApr 17Apr 28May 11
WrightApr 14Apr 29May 11

More Information

* This data was provided by the Midwestern Regional Climate Center (MRCC).  Visit that website to get more detailed information and statistics.