Frost dates for 61319Cornell, IL
The average last spring frost in Cornell is April 16 and the average first fall frost is October 24, giving a typical growing season of about 191 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 16
- Average first fall frost
- Oct 24
- Growing season
- 191 days
Safer after May 2 (1-in-10 risk)
Possible by Oct 12 (1-in-10 risk)
Last frost typically in 165 days
Frost risk by date
NOAA reports frost dates as probabilities. The middle date is the average (a 50% chance). For spring, the 10% date is a safer planting date: frost after it happens in about 1 year in 10. Light frost (36°F) can damage tender plants; a hard freeze (28°F) kills most annuals.
| Temperature | Last spring: 90% / 50% / 10% chance | First fall: 10% / 50% / 90% chance | Growing season (50%) | Years with at least one |
|---|---|---|---|---|
| Light frost (36°F) | Apr 13 · Apr 26 · May 11 | Oct 2 · Oct 15 · Oct 27 | 170 days | 100% |
| Frost / freeze (32°F) | Apr 3 · Apr 16 · May 2 | Oct 12 · Oct 24 · Nov 5 | 191 days | 100% |
| Hard freeze (28°F) | Mar 20 · Apr 4 · Apr 19 | Oct 23 · Nov 3 · Nov 18 | 213 days | 100% |
Planting calendar for Cornell
Planting windows from the University of Maryland Extension calendar, shifted to your average frost dates. Use them as a starting point and adjust for seed packet instructions and local conditions.
| Crop | Task | Window |
|---|---|---|
| Tomatoes | Start seeds indoors | Mar 16 – May 22 |
| Tomatoes | Transplant outdoors | May 2 – Jul 4 |
| Peppers | Start seeds indoors | Mar 16 – Apr 16 |
| Peppers | Transplant outdoors | May 16 – Jun 16 |
| Eggplant | Start seeds indoors | Apr 2 – May 1 |
| Eggplant | Transplant outdoors | May 16 – Jun 16 |
| Cucumbers | Sow outdoors | May 16 – Jul 14 |
| Summer squash | Sow outdoors | May 2 – Jun 16 |
| Winter squash & pumpkins | Sow outdoors | May 16 – Jun 16 |
| Snap beans | Sow outdoors | May 2 – Aug 6 |
| Sweet corn | Sow outdoors | May 2 – Jul 4 |
| Watermelon & cantaloupe | Sow outdoors | May 16 – Jun 16 |
| Okra | Sow outdoors | May 9 – Jun 1 |
| Peas | Sow outdoors (spring) | Mar 16 – May 1 |
| Potatoes | Plant outdoors (spring) | Mar 16 – May 16 |
| Onions | Start seeds indoors (spring) | Feb 2 – Mar 1 |
| Onions | Transplant outdoors (spring) | Apr 2 – May 1 |
| Broccoli | Start seeds indoors (spring) | Feb 26 – Apr 1 |
| Broccoli | Transplant outdoors (spring) | Apr 2 – May 1 |
| Broccoli | Start seeds indoors (fall) | Jun 24 – Jul 4 |
| Broccoli | Transplant outdoors (fall) | Jul 24 – Aug 4 |
| Cabbage | Start seeds indoors (spring) | Feb 16 – Mar 16 |
| Cabbage | Transplant outdoors (spring) | Mar 16 – Apr 16 |
| Cabbage | Start seeds indoors (fall) | Jun 14 – Jul 14 |
| Cabbage | Transplant outdoors (fall) | Jul 14 – Aug 14 |
| Leaf lettuce | Sow outdoors (spring) | Mar 16 – Jun 1 |
| Leaf lettuce | Sow outdoors (fall) | Jul 14 – Aug 30 |
| Spinach | Sow outdoors (spring) | Mar 9 – Apr 22 |
| Spinach | Sow outdoors (fall) | Jul 31 – Sep 4 |
| Radishes | Sow outdoors (spring) | Mar 16 – May 6 |
| Radishes | Sow outdoors (fall) | Jul 14 – Sep 14 |
| Kale | Sow outdoors (spring) | Apr 2 – Apr 22 |
| Kale | Sow outdoors (fall) | Jul 7 – Aug 14 |
| Carrots | Sow outdoors (spring) | Apr 16 – Jun 1 |
| Carrots | Sow outdoors (fall) | Jun 14 – Jul 30 |
| Garlic | Plant outdoors (fall) | Oct 14 – Nov 14 |
Where these dates come from
ZIP code 61319 is matched to the NOAA station Pontiac, IL, 20.3 km away, at 650 ft elevation (36 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Pontiac, IL (used) | 650 ft | Apr 16 | Oct 24 |
| Streator 3 Se, IL | 610 ft | Apr 12 | Oct 28 |
| Minonk, IL | 750 ft | Apr 26 | Oct 17 |
| Dwight, IL | 628 ft | Apr 27 | Oct 15 |
Frost dates near Cornell
- Ancona, IL 61311 · last Apr 12, first Oct 28
- Long Point, IL 61333 · last Apr 26, first Oct 17
- Blackstone, IL 61313 · last Apr 27, first Oct 15
- Streator, IL 61364 · last Apr 12, first Oct 28
- Ransom, IL 60470 · last Apr 27, first Oct 15
- Graymont, IL 61743 · last Apr 16, first Oct 24
- Dana, IL 61321 · last Apr 26, first Oct 17
- Flanagan, IL 61740 · last Apr 26, first Oct 17
Frequently asked questions
- When is the last frost in Cornell, IL?
- For ZIP code 61319, the average last spring frost (32°F) is April 16, based on NOAA 1991-2020 climate normals for the Pontiac, IL weather station. There is a 1-in-10 chance of a frost after May 2.
- When is the first frost in Cornell, IL?
- The average first fall frost (32°F) is October 24. There is a 1-in-10 chance of frost by October 12, so tender plants are at risk from that point on.
- How long is the growing season in 61319?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 191 days long.
- Are these frost dates a forecast?
- No. They are 30-year averages and probabilities from NOAA weather station records. Use them to plan, then watch your local forecast before planting tender crops or leaving them uncovered.