Last frost date in Aurora, IL
Expect the last frost in Aurora around April 19. Frost after May 4 happens in only one year out of ten. The first fall frost usually arrives about October 23, which leaves 185 frost-free days. An early freeze before October 9 happens one year in ten.
- Safe after (10% risk)
- May 4
- Average first frost
- Oct 23
- Frost-free season
- 185 days
- Hard freeze (28°F) ends
- Apr 8
No frost in the next 7 nights
National Weather Service forecast, updated Oct 22, 12:24 UTC
- ThuOct 2246°
- FriOct 2347°
- SatOct 2449°
- SunOct 2550°
- MonOct 2648°
- TueOct 2744°
- WedOct 2845°
Planting calendar for Aurora
Windows count forward or back from the average frost dates above. Click a crop for dates across Illinois.
Frost probabilities
| Threshold | Spring, 90% chance later | Spring, 50% | Spring, 10% | Fall, 10% chance earlier | Fall, 50% | Fall, 90% |
|---|---|---|---|---|---|---|
| Light frost, 32°F | Apr 5 | Apr 19 | May 4 | Oct 9 | Oct 23 | Nov 3 |
| Hard freeze, 28°F | Mar 25 | Apr 8 | Apr 23 | Oct 21 | Nov 2 | Nov 16 |
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 Aurora (USC00110338) sits 1.5 miles from the center of Aurora at 660 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 Aurora, IL?
The average last frost date in Aurora is April 19, based on NOAA 1991–2020 climate normals. There is a 10% chance of frost after May 4.
When is the first frost in Aurora?
The first frost in fall usually comes around October 23. One year in ten it arrives before October 9.
How long is the growing season in Aurora?
About 185 days between the average last and first frost.
When should I plant tomatoes in Aurora?
Plant tomato seedlings outside from April 26 to May 10. Start seeds indoors six to eight weeks earlier.
Nearby in Illinois
- MontgomeryApr 19
- BataviaApr 19
- OswegoApr 19
- NapervilleApr 28
- GenevaApr 25
- West ChicagoApr 25
- YorkvilleApr 28
- PlainfieldApr 20
- LisleApr 28
- St. CharlesApr 25
- BolingbrookApr 20
- WheatonApr 28