Frost dates for 16833Curwensville, PA
The average last spring frost in Curwensville is May 4 and the average first fall frost is October 11, giving a typical growing season of about 161 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 4
- Average first fall frost
- Oct 11
- Growing season
- 161 days
Safer after May 22 (1-in-10 risk)
Possible by Sep 29 (1-in-10 risk)
Last frost typically in 183 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 29 · May 17 · May 31 | Sep 17 · Sep 30 · Oct 12 | 136 days | 100% |
| Frost / freeze (32°F) | Apr 19 · May 4 · May 22 | Sep 29 · Oct 11 · Oct 29 | 161 days | 100% |
| Hard freeze (28°F) | Apr 8 · Apr 23 · May 11 | Oct 11 · Oct 27 · Nov 9 | 187 days | 100% |
Planting calendar for Curwensville
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 | Apr 3 – Jun 9 |
| Tomatoes | Transplant outdoors | May 20 – Jun 21 |
| Peppers | Start seeds indoors | Apr 3 – May 4 |
| Peppers | Transplant outdoors | Jun 3 – Jul 4 |
| Eggplant | Start seeds indoors | Apr 20 – May 19 |
| Eggplant | Transplant outdoors | Jun 3 – Jul 4 |
| Cucumbers | Sow outdoors | Jun 3 – Jul 1 |
| Summer squash | Sow outdoors | May 20 – Jul 4 |
| Winter squash & pumpkins | Sow outdoors | Jun 3 – Jul 4 |
| Snap beans | Sow outdoors | May 20 – Jul 24 |
| Sweet corn | Sow outdoors | May 20 – Jun 21 |
| Watermelon & cantaloupe | Sow outdoors | Jun 3 – Jul 4 |
| Okra | Sow outdoors | May 27 – Jun 19 |
| Peas | Sow outdoors (spring) | Apr 3 – May 19 |
| Potatoes | Plant outdoors (spring) | Apr 3 – Jun 3 |
| Onions | Start seeds indoors (spring) | Feb 20 – Mar 19 |
| Onions | Transplant outdoors (spring) | Apr 20 – May 19 |
| Broccoli | Start seeds indoors (spring) | Mar 16 – Apr 19 |
| Broccoli | Transplant outdoors (spring) | Apr 20 – May 19 |
| Broccoli | Start seeds indoors (fall) | Jun 11 – Jun 21 |
| Broccoli | Transplant outdoors (fall) | Jul 11 – Jul 22 |
| Cabbage | Start seeds indoors (spring) | Mar 6 – Apr 3 |
| Cabbage | Transplant outdoors (spring) | Apr 3 – May 4 |
| Cabbage | Start seeds indoors (fall) | Jun 1 – Jul 1 |
| Cabbage | Transplant outdoors (fall) | Jul 1 – Aug 1 |
| Leaf lettuce | Sow outdoors (spring) | Apr 3 – Jun 19 |
| Leaf lettuce | Sow outdoors (fall) | Jul 1 – Aug 17 |
| Spinach | Sow outdoors (spring) | Mar 27 – May 10 |
| Spinach | Sow outdoors (fall) | Jul 18 – Aug 22 |
| Radishes | Sow outdoors (spring) | Apr 3 – May 24 |
| Radishes | Sow outdoors (fall) | Jul 1 – Sep 1 |
| Kale | Sow outdoors (spring) | Apr 20 – May 10 |
| Kale | Sow outdoors (fall) | Jun 24 – Aug 1 |
| Carrots | Sow outdoors (spring) | May 4 – Jun 19 |
| Carrots | Sow outdoors (fall) | Jun 1 – Jul 17 |
| Garlic | Plant outdoors (fall) | Oct 1 – Nov 1 |
Where these dates come from
ZIP code 16833 is matched to the NOAA station Clearfield Lawrence Ap, PA, 13.2 km away, at 1,516 ft elevation (214 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Clearfield Lawrence Ap, PA (used) | 1,516 ft | May 4 | Oct 11 |
| Grampian 1E, PA | 1,510 ft | May 4 | Oct 13 |
| Philipsburg 2 S, PA | 1,720 ft | May 13 | Oct 1 |
| Prince Gallitzin Sp, PA | 1,520 ft | May 10 | Oct 5 |
Frost dates near Curwensville
- Glen Richey, PA 16837 · last May 4, first Oct 11
- Grampian, PA 16838 · last May 4, first Oct 11
- Hyde, PA 16843 · last May 4, first Oct 11
- Olanta, PA 16863 · last May 4, first Oct 11
- Smokerun, PA 16681 · last May 4, first Oct 11
- Clearfield, PA 16830 · last May 4, first Oct 11
- New Millport, PA 16861 · last May 4, first Oct 11
- Mineral Springs, PA 16855 · last May 4, first Oct 11
Frequently asked questions
- When is the last frost in Curwensville, PA?
- For ZIP code 16833, the average last spring frost (32°F) is May 4, based on NOAA 1991-2020 climate normals for the Clearfield Lawrence Ap, PA weather station. There is a 1-in-10 chance of a frost after May 22.
- When is the first frost in Curwensville, PA?
- The average first fall frost (32°F) is October 11. There is a 1-in-10 chance of frost by September 29, so tender plants are at risk from that point on.
- How long is the growing season in 16833?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 161 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.