Last frost date in Oak Forest, IL
Expect the last frost in Oak Forest around April 23. Frost after May 11 happens in only one year out of ten. The first fall frost usually arrives about October 20, which leaves 179 frost-free days. An early freeze before October 6 happens one year in ten.
- Safe after (10% risk)
- May 11
- Average first frost
- Oct 20
- Frost-free season
- 179 days
- Hard freeze (28°F) ends
- Apr 12
No frost in the next 7 nights
Later than usual: the average first frost here is October 20.
National Weather Service forecast, updated Oct 22, 12:57 UTC
- ThuOct 2248°
- FriOct 2349°
- SatOct 2451°
- SunOct 2552°
- MonOct 2650°
- TueOct 2747°
- WedOct 2848°
Planting calendar for Oak Forest
Windows count forward or back from the average frost dates above. Click a crop for dates across Illinois.
TomatoesApr 30–May 14
PumpkinsMay 7–May 21
SunflowersApr 23–May 14
CucumbersMay 7–May 14
CornApr 30–May 14
Sweet potatoesMay 14–May 28
WatermelonMay 7–May 21
Green beansApr 30–May 21
ZucchiniApr 30–May 14
OkraMay 14–May 28
PeppersMay 7–May 21
BasilApr 30–May 14
Butternut squashApr 30–May 14
CantaloupeMay 7–May 21
EggplantMay 7–May 21
PotatoesMar 26–Apr 9
OnionsMar 12–Apr 2
CarrotsApr 2–May 7
LettuceApr 9–Apr 30
BroccoliMar 26–Apr 9
BeetsMar 26–May 7
PeasMar 12–Mar 26
CabbageMar 26–Apr 9
RadishesMar 19–Apr 30
Brussels sproutsApr 9–Apr 23
SpinachMar 12–Apr 2
CilantroApr 9–Apr 30
KaleMar 26–Apr 9
Collard greensMar 26–Apr 9
TurnipsMar 26–Apr 9
DillApr 23–May 7
CeleryApr 30–May 7
CauliflowerApr 9–Apr 23
LeeksApr 9–Apr 23
Swiss chardApr 9–May 7
ParsleyApr 9–Apr 30
Tulip bulbsOct 6–Nov 10
GarlicSep 29–Nov 3
Daffodil bulbsSep 22–Nov 3
StrawberriesMar 26–Apr 9
AsparagusMar 26–Apr 9Frost probabilities
| Threshold | Spring, 90% chance later | Spring, 50% | Spring, 10% | Fall, 10% chance earlier | Fall, 50% | Fall, 90% |
|---|---|---|---|---|---|---|
| Light frost, 32°F | Apr 9 | Apr 23 | May 11 | Oct 6 | Oct 20 | Nov 1 |
| Hard freeze, 28°F | Mar 30 | Apr 12 | Apr 27 | Oct 18 | Oct 30 | Nov 15 |
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 Park Forest (USC00116616) sits 8.6 miles from the center of Oak Forest at 710 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 Oak Forest, IL?
The average last frost date in Oak Forest is April 23, based on NOAA 1991–2020 climate normals. There is a 10% chance of frost after May 11.
When is the first frost in Oak Forest?
The first frost in fall usually comes around October 20. One year in ten it arrives before October 6.
How long is the growing season in Oak Forest?
About 179 days between the average last and first frost.
When should I plant tomatoes in Oak Forest?
Plant tomato seedlings outside from April 30 to May 14. Start seeds indoors six to eight weeks earlier.
Nearby in Illinois
- Tinley ParkApr 23
- Blue IslandApr 10
- Orland ParkApr 19
- Oak LawnApr 10
- South HollandApr 23
- DoltonApr 23
- Chicago HeightsApr 23
- FrankfortApr 23
- Park ForestApr 23
- BurbankApr 10
- Homer GlenApr 20
- LansingApr 23