Frost dates for 81650Rifle, CO
The average last spring frost in Rifle is May 11 and the average first fall frost is October 4, giving a typical growing season of about 143 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 11
- Average first fall frost
- Oct 4
- Growing season
- 143 days
Safer after May 27 (1-in-10 risk)
Possible by Sep 23 (1-in-10 risk)
Last frost typically in 196 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) | May 12 · May 26 · Jun 8 | Sep 12 · Sep 25 · Oct 6 | 119 days | 100% |
| Frost / freeze (32°F) | Apr 28 · May 11 · May 27 | Sep 23 · Oct 4 · Oct 17 | 143 days | 100% |
| Hard freeze (28°F) | Apr 14 · Apr 28 · May 11 | Sep 30 · Oct 15 · Oct 27 | 167 days | 100% |
Planting calendar for Rifle
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 10 – Jun 16 |
| Tomatoes | Transplant outdoors | May 27 – Jun 14 |
| Peppers | Start seeds indoors | Apr 10 – May 11 |
| Peppers | Transplant outdoors | Jun 10 – Jul 11 |
| Eggplant | Start seeds indoors | Apr 27 – May 26 |
| Eggplant | Transplant outdoors | Jun 10 – Jul 11 |
| Cucumbers | Sow outdoors | Jun 10 – Jun 24 |
| Summer squash | Sow outdoors | May 27 – Jul 11 |
| Winter squash & pumpkins | Sow outdoors | Jun 10 – Jul 11 |
| Snap beans | Sow outdoors | May 27 – Jul 17 |
| Sweet corn | Sow outdoors | May 27 – Jun 14 |
| Watermelon & cantaloupe | Sow outdoors | Jun 10 – Jul 11 |
| Okra | Sow outdoors | Jun 3 – Jun 26 |
| Peas | Sow outdoors (spring) | Apr 10 – May 26 |
| Potatoes | Plant outdoors (spring) | Apr 10 – Jun 10 |
| Onions | Start seeds indoors (spring) | Feb 27 – Mar 26 |
| Onions | Transplant outdoors (spring) | Apr 27 – May 26 |
| Broccoli | Start seeds indoors (spring) | Mar 23 – Apr 26 |
| Broccoli | Transplant outdoors (spring) | Apr 27 – May 26 |
| Broccoli | Start seeds indoors (fall) | Jun 4 – Jun 14 |
| Broccoli | Transplant outdoors (fall) | Jul 4 – Jul 15 |
| Cabbage | Start seeds indoors (spring) | Mar 13 – Apr 10 |
| Cabbage | Transplant outdoors (spring) | Apr 10 – May 11 |
| Cabbage | Start seeds indoors (fall) | May 25 – Jun 24 |
| Cabbage | Transplant outdoors (fall) | Jun 24 – Jul 25 |
| Leaf lettuce | Sow outdoors (spring) | Apr 10 – Jun 26 |
| Leaf lettuce | Sow outdoors (fall) | Jun 24 – Aug 10 |
| Spinach | Sow outdoors (spring) | Apr 3 – May 17 |
| Spinach | Sow outdoors (fall) | Jul 11 – Aug 15 |
| Radishes | Sow outdoors (spring) | Apr 10 – May 31 |
| Radishes | Sow outdoors (fall) | Jun 24 – Aug 25 |
| Kale | Sow outdoors (spring) | Apr 27 – May 17 |
| Kale | Sow outdoors (fall) | Jun 17 – Jul 25 |
| Carrots | Sow outdoors (spring) | May 11 – Jun 26 |
| Carrots | Sow outdoors (fall) | May 25 – Jul 10 |
| Garlic | Plant outdoors (fall) | Sep 24 – Oct 25 |
Where these dates come from
ZIP code 81650 is matched to the NOAA station Rifle Garfield Co Ap, CO, 6 km away, at 5,530 ft elevation (90 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Rifle Garfield Co Ap, CO (used) | 5,530 ft | May 11 | Oct 4 |
| Rifle 3Ene, CO | 5,469 ft | May 23 | Sep 25 |
| Collbran 1Wsw, CO | 6,009 ft | May 17 | Sep 30 |
| Glenwood Spgs #2, CO | 5,895 ft | May 13 | Oct 3 |
Frost dates near Rifle
- Silt, CO 81652 · last May 11, first Oct 4
- New Castle, CO 81647 · last May 11, first Oct 4
- Battlement Mesa, CO 81636 · last May 11, first Oct 4
- Parachute, CO 81635 · last May 11, first Oct 4
- Collbran, CO 81624 · last May 17, first Sep 30
- Glenwood Springs, CO 81602 · last May 13, first Oct 3
- De Beque, CO 81630 · last Apr 17, first Oct 26
- Molina, CO 81646 · last May 17, first Sep 30
Frequently asked questions
- When is the last frost in Rifle, CO?
- For ZIP code 81650, the average last spring frost (32°F) is May 11, based on NOAA 1991-2020 climate normals for the Rifle Garfield Co Ap, CO weather station. There is a 1-in-10 chance of a frost after May 27.
- When is the first frost in Rifle, CO?
- The average first fall frost (32°F) is October 4. There is a 1-in-10 chance of frost by September 23, so tender plants are at risk from that point on.
- How long is the growing season in 81650?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 143 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.