Frost dates for 84628Eureka, UT
The average last spring frost in Eureka is June 1 and the average first fall frost is September 20, giving a typical growing season of about 110 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Jun 1
- Average first fall frost
- Sep 20
- Growing season
- 110 days
Safer after Jun 19 (1-in-10 risk)
Possible by Sep 4 (1-in-10 risk)
Last frost typically in 218 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 31 · Jun 13 · Jun 28 | Aug 26 · Sep 9 · Sep 25 | 88 days | 100% |
| Frost / freeze (32°F) | May 18 · Jun 1 · Jun 19 | Sep 4 · Sep 20 · Oct 3 | 110 days | 100% |
| Hard freeze (28°F) | May 3 · May 19 · Jun 8 | Sep 15 · Sep 29 · Oct 13 | 133 days | 100% |
Planting calendar for Eureka
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 31 |
| 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 10 |
| Summer squash | Sow outdoors | Jun 17 – Aug 1 |
| Winter squash & pumpkins | Sow outdoors | Jul 1 – Aug 1 |
| Snap beans | Sow outdoors | Jun 17 – Jul 3 |
| Sweet corn | Sow outdoors | Jun 17 – May 31 |
| 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 21 – May 31 |
| Broccoli | Transplant outdoors (fall) | Jun 20 – Jul 1 |
| Cabbage | Start seeds indoors (spring) | Apr 3 – May 1 |
| Cabbage | Transplant outdoors (spring) | May 1 – Jun 1 |
| Cabbage | Start seeds indoors (fall) | May 11 – Jun 10 |
| Cabbage | Transplant outdoors (fall) | Jun 10 – Jul 11 |
| Leaf lettuce | Sow outdoors (spring) | May 1 – Jul 17 |
| Leaf lettuce | Sow outdoors (fall) | Jun 10 – Jul 27 |
| Spinach | Sow outdoors (spring) | Apr 24 – Jun 7 |
| Spinach | Sow outdoors (fall) | Jun 27 – Aug 1 |
| Radishes | Sow outdoors (spring) | May 1 – Jun 21 |
| Radishes | Sow outdoors (fall) | Jun 10 – Aug 11 |
| Kale | Sow outdoors (spring) | May 18 – Jun 7 |
| Kale | Sow outdoors (fall) | Jun 3 – Jul 11 |
| Carrots | Sow outdoors (spring) | Jun 1 – Jul 17 |
| Carrots | Sow outdoors (fall) | May 11 – Jun 26 |
| Garlic | Plant outdoors (fall) | Sep 10 – Oct 11 |
Where these dates come from
ZIP code 84628 is matched to the NOAA station Vernon, UT, 31.4 km away, at 5,471 ft elevation (1,022 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Vernon, UT (used) | 5,471 ft | Jun 1 | Sep 20 |
| Santaquin Chlorinator, UT | 5,160 ft | May 4 | Oct 11 |
| Little Sahara Rec Area, UT | 5,230 ft | May 15 | Oct 1 |
| Fairfield, UT | 4,880 ft | Jun 2 | Sep 16 |
Frost dates near Eureka
- Elberta, UT 84626 · last Apr 25, first Oct 18
- Goshen, UT 84633 · last Apr 25, first Oct 18
- Mona, UT 84645 · last May 6, first Oct 10
- Santaquin, UT 84655 · last May 4, first Oct 11
- Vernon, UT 84080 · last Jun 1, first Sep 20
- Payson, UT 84651 · last Apr 25, first Oct 18
- Nephi, UT 84648 · last May 6, first Oct 10
- Cedar Valley, UT 84013 · last Jun 2, first Sep 16
Frequently asked questions
- When is the last frost in Eureka, UT?
- For ZIP code 84628, the average last spring frost (32°F) is June 1, based on NOAA 1991-2020 climate normals for the Vernon, UT weather station. There is a 1-in-10 chance of a frost after June 19.
- When is the first frost in Eureka, UT?
- The average first fall frost (32°F) is September 20. There is a 1-in-10 chance of frost by September 4, so tender plants are at risk from that point on.
- How long is the growing season in 84628?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 110 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.