Frost dates for 12518Cornwall, NY
The average last spring frost in Cornwall is April 10 and the average first fall frost is November 1, giving a typical growing season of about 204 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Apr 10
- Average first fall frost
- Nov 1
- Growing season
- 204 days
Safer after Apr 24 (1-in-10 risk)
Possible by Oct 16 (1-in-10 risk)
Last frost typically in 158 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 10 · Apr 23 · May 7 | Oct 7 · Oct 20 · Nov 3 | 179 days | 100% |
| Frost / freeze (32°F) | Mar 31 · Apr 10 · Apr 24 | Oct 16 · Nov 1 · Nov 14 | 204 days | 100% |
| Hard freeze (28°F) | Mar 19 · Apr 2 · Apr 14 | Oct 29 · Nov 12 · Nov 27 | 223 days | 100% |
Planting calendar for Cornwall
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 10 – May 16 |
| Tomatoes | Transplant outdoors | Apr 26 – Jul 12 |
| Peppers | Start seeds indoors | Mar 10 – Apr 10 |
| Peppers | Transplant outdoors | May 10 – Jun 10 |
| Eggplant | Start seeds indoors | Mar 27 – Apr 25 |
| Eggplant | Transplant outdoors | May 10 – Jun 10 |
| Cucumbers | Sow outdoors | May 10 – Jul 22 |
| Summer squash | Sow outdoors | Apr 26 – Jun 10 |
| Winter squash & pumpkins | Sow outdoors | May 10 – Jun 10 |
| Snap beans | Sow outdoors | Apr 26 – Aug 14 |
| Sweet corn | Sow outdoors | Apr 26 – Jul 12 |
| Watermelon & cantaloupe | Sow outdoors | May 10 – Jun 10 |
| Okra | Sow outdoors | May 3 – May 26 |
| Peas | Sow outdoors (spring) | Mar 10 – Apr 25 |
| Potatoes | Plant outdoors (spring) | Mar 10 – May 10 |
| Onions | Start seeds indoors (spring) | Jan 27 – Feb 23 |
| Onions | Transplant outdoors (spring) | Mar 27 – Apr 25 |
| Broccoli | Start seeds indoors (spring) | Feb 20 – Mar 26 |
| Broccoli | Transplant outdoors (spring) | Mar 27 – Apr 25 |
| Broccoli | Start seeds indoors (fall) | Jul 2 – Jul 12 |
| Broccoli | Transplant outdoors (fall) | Aug 1 – Aug 12 |
| Cabbage | Start seeds indoors (spring) | Feb 10 – Mar 10 |
| Cabbage | Transplant outdoors (spring) | Mar 10 – Apr 10 |
| Cabbage | Start seeds indoors (fall) | Jun 22 – Jul 22 |
| Cabbage | Transplant outdoors (fall) | Jul 22 – Aug 22 |
| Leaf lettuce | Sow outdoors (spring) | Mar 10 – May 26 |
| Leaf lettuce | Sow outdoors (fall) | Jul 22 – Sep 7 |
| Spinach | Sow outdoors (spring) | Mar 3 – Apr 16 |
| Spinach | Sow outdoors (fall) | Aug 8 – Sep 12 |
| Radishes | Sow outdoors (spring) | Mar 10 – Apr 30 |
| Radishes | Sow outdoors (fall) | Jul 22 – Sep 22 |
| Kale | Sow outdoors (spring) | Mar 27 – Apr 16 |
| Kale | Sow outdoors (fall) | Jul 15 – Aug 22 |
| Carrots | Sow outdoors (spring) | Apr 10 – May 26 |
| Carrots | Sow outdoors (fall) | Jun 22 – Aug 7 |
| Garlic | Plant outdoors (fall) | Oct 22 – Nov 22 |
Where these dates come from
ZIP code 12518 is matched to the NOAA station West Point, NY, 7.2 km away, at 320 ft elevation (274 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| West Point, NY (used) | 320 ft | Apr 10 | Nov 1 |
| Walden 1 Ese, NY | 380 ft | Apr 29 | Oct 11 |
| Shrub Oak, NY | 462 ft | Apr 30 | Oct 17 |
| Montgomery Orange Ap, NY | 365 ft | May 1 | Oct 11 |
Frost dates near Cornwall
- Cornwall On Hudson, NY 12520 · last Apr 10, first Nov 1
- Mountainville, NY 10953 · last Apr 10, first Nov 1
- Vails Gate, NY 12584 · last Apr 10, first Nov 1
- West Point, NY 10996 · last Apr 10, first Nov 1
- New Windsor, NY 12553 · last Apr 29, first Oct 11
- Salisbury Mills, NY 12577 · last Apr 29, first Oct 11
- Highland Falls, NY 10928 · last Apr 10, first Nov 1
- Cold Spring, NY 10516 · last Apr 10, first Nov 1
Frequently asked questions
- When is the last frost in Cornwall, NY?
- For ZIP code 12518, the average last spring frost (32°F) is April 10, based on NOAA 1991-2020 climate normals for the West Point, NY weather station. There is a 1-in-10 chance of a frost after April 24.
- When is the first frost in Cornwall, NY?
- The average first fall frost (32°F) is November 1. There is a 1-in-10 chance of frost by October 16, so tender plants are at risk from that point on.
- How long is the growing season in 12518?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 204 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.