Frost dates for 82944Robertson, WY
The average last spring frost in Robertson is June 11 and the average first fall frost is September 18, giving a typical growing season of about 97 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Jun 11
- Average first fall frost
- Sep 18
- Growing season
- 97 days
Safer after Jun 24 (1-in-10 risk)
Possible by Sep 5 (1-in-10 risk)
Last frost typically in 227 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) | Jun 9 · Jun 22 · Jul 6 | Aug 26 · Sep 9 · Sep 21 | 77 days | 100% |
| Frost / freeze (32°F) | May 29 · Jun 11 · Jun 24 | Sep 5 · Sep 18 · Sep 30 | 97 days | 100% |
| Hard freeze (28°F) | May 15 · Jun 1 · Jun 14 | Sep 14 · Sep 28 · Oct 12 | 118 days | 100% |
Planting calendar for Robertson
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 11 – Jul 17 |
| Tomatoes | Transplant outdoors | Jun 27 – May 29 |
| Peppers | Start seeds indoors | May 11 – Jun 11 |
| Peppers | Transplant outdoors | Jul 11 – Aug 11 |
| Eggplant | Start seeds indoors | May 28 – Jun 26 |
| Eggplant | Transplant outdoors | Jul 11 – Aug 11 |
| Cucumbers | Sow outdoors | Jul 11 – Jun 8 |
| Summer squash | Sow outdoors | Jun 27 – Aug 11 |
| Winter squash & pumpkins | Sow outdoors | Jul 11 – Aug 11 |
| Snap beans | Sow outdoors | Jun 27 – Jul 1 |
| Sweet corn | Sow outdoors | Jun 27 – May 29 |
| Watermelon & cantaloupe | Sow outdoors | Jul 11 – Aug 11 |
| Okra | Sow outdoors | Jul 4 – Jul 27 |
| Peas | Sow outdoors (spring) | May 11 – Jun 26 |
| Potatoes | Plant outdoors (spring) | May 11 – Jul 11 |
| Onions | Start seeds indoors (spring) | Mar 30 – Apr 26 |
| Onions | Transplant outdoors (spring) | May 28 – Jun 26 |
| Broccoli | Start seeds indoors (spring) | Apr 23 – May 27 |
| Broccoli | Transplant outdoors (spring) | May 28 – Jun 26 |
| Broccoli | Start seeds indoors (fall) | May 19 – May 29 |
| Broccoli | Transplant outdoors (fall) | Jun 18 – Jun 29 |
| Cabbage | Start seeds indoors (spring) | Apr 13 – May 11 |
| Cabbage | Transplant outdoors (spring) | May 11 – Jun 11 |
| Cabbage | Start seeds indoors (fall) | May 9 – Jun 8 |
| Cabbage | Transplant outdoors (fall) | Jun 8 – Jul 9 |
| Leaf lettuce | Sow outdoors (spring) | May 11 – Jul 27 |
| Leaf lettuce | Sow outdoors (fall) | Jun 8 – Jul 25 |
| Spinach | Sow outdoors (spring) | May 4 – Jun 17 |
| Spinach | Sow outdoors (fall) | Jun 25 – Jul 30 |
| Radishes | Sow outdoors (spring) | May 11 – Jul 1 |
| Radishes | Sow outdoors (fall) | Jun 8 – Aug 9 |
| Kale | Sow outdoors (spring) | May 28 – Jun 17 |
| Kale | Sow outdoors (fall) | Jun 1 – Jul 9 |
| Carrots | Sow outdoors (spring) | Jun 11 – Jul 27 |
| Carrots | Sow outdoors (fall) | May 9 – Jun 24 |
| Garlic | Plant outdoors (fall) | Sep 8 – Oct 9 |
Where these dates come from
ZIP code 82944 is matched to the NOAA station Moon Lake, UT, 59.8 km away, at 8,125 ft elevation (303 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Moon Lake, UT (used) | 8,125 ft | Jun 11 | Sep 18 |
| Mtn View, WY | 6,800 ft | Jun 14 | Sep 9 |
| Evanston 1 E, WY | 6,825 ft | Jun 12 | Sep 12 |
| Church Buttes Gas Plt, WY | 7,079 ft | May 25 | Sep 27 |
Frost dates near Robertson
- Mountain View, WY 82939 · last Jun 14, first Sep 9
- Fort Bridger, WY 82933 · last Jun 14, first Sep 9
- Lonetree, WY 82936 · last May 25, first Sep 27
- Lyman, WY 82937 · last Jun 14, first Sep 9
- Evanston, WY 82931 · last Jun 12, first Sep 12
- Mc Kinnon, WY 82938 · last May 22, first Sep 29
- Manila, UT 84046 · last May 22, first Sep 29
- Granger, WY 82934 · last May 24, first Sep 22
Frequently asked questions
- When is the last frost in Robertson, WY?
- For ZIP code 82944, the average last spring frost (32°F) is June 11, based on NOAA 1991-2020 climate normals for the Moon Lake, UT weather station. There is a 1-in-10 chance of a frost after June 24.
- When is the first frost in Robertson, WY?
- The average first fall frost (32°F) is September 18. There is a 1-in-10 chance of frost by September 5, so tender plants are at risk from that point on.
- How long is the growing season in 82944?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 97 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.