Last frost date in Chicago, IL
The average last frost in Chicago is April 10. By April 25 the chance of another 32°F night drops to 1 in 10. The first fall frost usually arrives about November 5, which leaves 208 frost-free days. An early freeze before October 24 happens one year in ten.
- Safe after (10% risk)
- Apr 25
- Average first frost
- Nov 5
- Frost-free season
- 208 days
- Hard freeze (28°F) ends
- Apr 1
No frost in the next 6 nights
National Weather Service forecast, updated Oct 22, 11:10 UTC
- ThuOct 2251°
- FriOct 2351°
- SatOct 2452°
- SunOct 2553°
- MonOct 2650°
- TueOct 2747°
Planting calendar for Chicago
Windows count forward or back from the average frost dates above. Click a crop for dates across Illinois.
TomatoesApr 17–May 1
PumpkinsApr 24–May 8
SunflowersApr 10–May 1
CucumbersApr 24–May 1
CornApr 17–May 1
Sweet potatoesMay 1–May 15
WatermelonApr 24–May 8
Green beansApr 17–May 8
ZucchiniApr 17–May 1
OkraMay 1–May 15
PeppersApr 24–May 8
BasilApr 17–May 1
Butternut squashApr 17–May 1
CantaloupeApr 24–May 8
EggplantApr 24–May 8
PotatoesMar 13–Mar 27
OnionsFeb 27–Mar 20
CarrotsMar 20–Apr 24
LettuceMar 27–Apr 17
BroccoliMar 13–Mar 27
BeetsMar 13–Apr 24
PeasFeb 27–Mar 13
CabbageMar 13–Mar 27
RadishesMar 6–Apr 17
Brussels sproutsMar 27–Apr 10
SpinachFeb 27–Mar 20
CilantroMar 27–Apr 17
KaleMar 13–Mar 27
Collard greensMar 13–Mar 27
TurnipsMar 13–Mar 27
DillApr 10–Apr 24
CeleryApr 17–Apr 24
CauliflowerMar 27–Apr 10
LeeksMar 27–Apr 10
Swiss chardMar 27–Apr 24
ParsleyMar 27–Apr 17
Tulip bulbsOct 22–Nov 26
GarlicOct 15–Nov 19
Daffodil bulbsOct 8–Nov 19
StrawberriesMar 13–Mar 27
AsparagusMar 13–Mar 27Frost probabilities
| Threshold | Spring, 90% chance later | Spring, 50% | Spring, 10% | Fall, 10% chance earlier | Fall, 50% | Fall, 90% |
|---|---|---|---|---|---|---|
| Light frost, 32°F | Mar 29 | Apr 10 | Apr 25 | Oct 24 | Nov 5 | Nov 20 |
| Hard freeze, 28°F | Mar 16 | Apr 1 | Apr 14 | Nov 2 | Nov 15 | Dec 1 |
Read the spring 10% column as the date after which only one year in ten still gets frost. That is the safer date for tomatoes, peppers and basil.
Where these numbers come from
NOAA station Chicago Northerly Is (USC00111550) sits 4.1 miles from the center of Chicago at 583 feet. Its averages cover 1991 to 2020. Low spots, valleys and open fields can keep getting frost a week or two after the station stops; city centers and lakeshores usually get less of it.
Questions
When is the last frost in Chicago, IL?
The average last frost date in Chicago is April 10, based on NOAA 1991–2020 climate normals. There is a 10% chance of frost after April 25.
When is the first frost in Chicago?
The first frost in fall usually comes around November 5. One year in ten it arrives before October 24.
How long is the growing season in Chicago?
About 208 days between the average last and first frost.
When should I plant tomatoes in Chicago?
Plant tomato seedlings outside from April 17 to May 1. Start seeds indoors six to eight weeks earlier.
Nearby in Illinois
- CiceroApr 11
- BerwynApr 11
- Oak ParkApr 11
- BurbankApr 10
- MaywoodApr 11
- Elmwood ParkApr 16
- Oak LawnApr 10
- Melrose ParkApr 16
- Blue IslandApr 10
- ElmhurstApr 16
- SkokieApr 26
- EvanstonApr 26