Frost dates for 82334Sinclair, WY
The average last spring frost in Sinclair is June 1 and the average first fall frost is September 15, giving a typical growing season of about 105 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Jun 1
- Average first fall frost
- Sep 15
- Growing season
- 105 days
Safer after Jun 17 (1-in-10 risk)
Possible by Sep 3 (1-in-10 risk)
Last frost typically in 217 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) | — | — | 80 days | 100% |
| Frost / freeze (32°F) | May 17 · Jun 1 · Jun 17 | Sep 3 · Sep 15 · Sep 29 | 105 days | 100% |
| Hard freeze (28°F) | May 3 · May 17 · Jun 3 | Sep 12 · Sep 26 · Oct 9 | 130 days | 100% |
Planting calendar for Sinclair
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 | May 1 – Jul 7 |
| Tomatoes | Transplant outdoors | Jun 17 – May 26 |
| Peppers | Start seeds indoors | May 1 – Jun 1 |
| Peppers | Transplant outdoors | Jul 1 – Aug 1 |
| Eggplant | Start seeds indoors | May 18 – Jun 16 |
| Eggplant | Transplant outdoors | Jul 1 – Aug 1 |
| Cucumbers | Sow outdoors | Jul 1 – Jun 5 |
| Summer squash | Sow outdoors | Jun 17 – Aug 1 |
| Winter squash & pumpkins | Sow outdoors | Jul 1 – Aug 1 |
| Snap beans | Sow outdoors | Jun 17 – Jun 28 |
| Sweet corn | Sow outdoors | Jun 17 – May 26 |
| Watermelon & cantaloupe | Sow outdoors | Jul 1 – Aug 1 |
| Okra | Sow outdoors | Jun 24 – Jul 17 |
| Peas | Sow outdoors (spring) | May 1 – Jun 16 |
| Potatoes | Plant outdoors (spring) | May 1 – Jul 1 |
| Onions | Start seeds indoors (spring) | Mar 20 – Apr 16 |
| Onions | Transplant outdoors (spring) | May 18 – Jun 16 |
| Broccoli | Start seeds indoors (spring) | Apr 13 – May 17 |
| Broccoli | Transplant outdoors (spring) | May 18 – Jun 16 |
| Broccoli | Start seeds indoors (fall) | May 16 – May 26 |
| Broccoli | Transplant outdoors (fall) | Jun 15 – Jun 26 |
| Cabbage | Start seeds indoors (spring) | Apr 3 – May 1 |
| Cabbage | Transplant outdoors (spring) | May 1 – Jun 1 |
| Cabbage | Start seeds indoors (fall) | May 6 – Jun 5 |
| Cabbage | Transplant outdoors (fall) | Jun 5 – Jul 6 |
| Leaf lettuce | Sow outdoors (spring) | May 1 – Jul 17 |
| Leaf lettuce | Sow outdoors (fall) | Jun 5 – Jul 22 |
| Spinach | Sow outdoors (spring) | Apr 24 – Jun 7 |
| Spinach | Sow outdoors (fall) | Jun 22 – Jul 27 |
| Radishes | Sow outdoors (spring) | May 1 – Jun 21 |
| Radishes | Sow outdoors (fall) | Jun 5 – Aug 6 |
| Kale | Sow outdoors (spring) | May 18 – Jun 7 |
| Kale | Sow outdoors (fall) | May 29 – Jul 6 |
| Carrots | Sow outdoors (spring) | Jun 1 – Jul 17 |
| Carrots | Sow outdoors (fall) | May 6 – Jun 21 |
| Garlic | Plant outdoors (fall) | Sep 5 – Oct 6 |
Where these dates come from
ZIP code 82334 is matched to the NOAA station Rawlins Muni Ap, WY, 7.4 km away, at 6,736 ft elevation (132 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Rawlins Muni Ap, WY (used) | 6,736 ft | Jun 1 | Sep 15 |
| Rawlins 1N, WY | 6,908 ft | May 17 | Oct 2 |
| Saratoga 4N, WY | 6,801 ft | Jun 12 | Sep 7 |
| Saratoga, WY | 6,790 ft | Jun 2 | Sep 12 |
Frost dates near Sinclair
- Rawlins, WY 82301 · last Jun 1, first Sep 15
- Shirley Basin, WY 82615 · last Jun 1, first Sep 15
- Walcott, WY 82335 · last Jun 1, first Sep 15
- Saratoga, WY 82331 · last Jun 12, first Sep 7
- Hanna, WY 82327 · last Jun 1, first Sep 8
- Elk Mountain, WY 82324 · last May 28, first Sep 13
- Bairoil, WY 82322 · last May 21, first Sep 27
- Encampment, WY 82325 · last May 28, first Sep 13
Frequently asked questions
- When is the last frost in Sinclair, WY?
- For ZIP code 82334, the average last spring frost (32°F) is June 1, based on NOAA 1991-2020 climate normals for the Rawlins Muni Ap, WY weather station. There is a 1-in-10 chance of a frost after June 17.
- When is the first frost in Sinclair, WY?
- The average first fall frost (32°F) is September 15. There is a 1-in-10 chance of frost by September 3, so tender plants are at risk from that point on.
- How long is the growing season in 82334?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 105 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.