Frost dates for 84316Howell, UT
The average last spring frost in Howell is May 12 and the average first fall frost is October 5, giving a typical growing season of about 144 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 12
- Average first fall frost
- Oct 5
- Growing season
- 144 days
Safer after Jun 8 (1-in-10 risk)
Possible by Sep 24 (1-in-10 risk)
Last frost typically in 198 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 11 · Jun 1 · Jun 19 | Sep 10 · Sep 25 · Oct 7 | 114 days | 100% |
| Frost / freeze (32°F) | Apr 27 · May 12 · Jun 8 | Sep 24 · Oct 5 · Oct 18 | 144 days | 100% |
| Hard freeze (28°F) | Apr 12 · Apr 27 · May 13 | Oct 2 · Oct 15 · Oct 27 | 171 days | 100% |
Planting calendar for Howell
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 11 – Jun 17 |
| Tomatoes | Transplant outdoors | May 28 – Jun 15 |
| Peppers | Start seeds indoors | Apr 11 – May 12 |
| Peppers | Transplant outdoors | Jun 11 – Jul 12 |
| Eggplant | Start seeds indoors | Apr 28 – May 27 |
| Eggplant | Transplant outdoors | Jun 11 – Jul 12 |
| Cucumbers | Sow outdoors | Jun 11 – Jun 25 |
| Summer squash | Sow outdoors | May 28 – Jul 12 |
| Winter squash & pumpkins | Sow outdoors | Jun 11 – Jul 12 |
| Snap beans | Sow outdoors | May 28 – Jul 18 |
| Sweet corn | Sow outdoors | May 28 – Jun 15 |
| Watermelon & cantaloupe | Sow outdoors | Jun 11 – Jul 12 |
| Okra | Sow outdoors | Jun 4 – Jun 27 |
| Peas | Sow outdoors (spring) | Apr 11 – May 27 |
| Potatoes | Plant outdoors (spring) | Apr 11 – Jun 11 |
| Onions | Start seeds indoors (spring) | Feb 28 – Mar 27 |
| Onions | Transplant outdoors (spring) | Apr 28 – May 27 |
| Broccoli | Start seeds indoors (spring) | Mar 24 – Apr 27 |
| Broccoli | Transplant outdoors (spring) | Apr 28 – May 27 |
| Broccoli | Start seeds indoors (fall) | Jun 5 – Jun 15 |
| Broccoli | Transplant outdoors (fall) | Jul 5 – Jul 16 |
| Cabbage | Start seeds indoors (spring) | Mar 14 – Apr 11 |
| Cabbage | Transplant outdoors (spring) | Apr 11 – May 12 |
| Cabbage | Start seeds indoors (fall) | May 26 – Jun 25 |
| Cabbage | Transplant outdoors (fall) | Jun 25 – Jul 26 |
| Leaf lettuce | Sow outdoors (spring) | Apr 11 – Jun 27 |
| Leaf lettuce | Sow outdoors (fall) | Jun 25 – Aug 11 |
| Spinach | Sow outdoors (spring) | Apr 4 – May 18 |
| Spinach | Sow outdoors (fall) | Jul 12 – Aug 16 |
| Radishes | Sow outdoors (spring) | Apr 11 – Jun 1 |
| Radishes | Sow outdoors (fall) | Jun 25 – Aug 26 |
| Kale | Sow outdoors (spring) | Apr 28 – May 18 |
| Kale | Sow outdoors (fall) | Jun 18 – Jul 26 |
| Carrots | Sow outdoors (spring) | May 12 – Jun 27 |
| Carrots | Sow outdoors (fall) | May 26 – Jul 11 |
| Garlic | Plant outdoors (fall) | Sep 25 – Oct 26 |
Where these dates come from
ZIP code 84316 is matched to the NOAA station Brigham City 28 Wnw, UT, 21.3 km away, at 4,951 ft elevation (16 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Brigham City 28 Wnw, UT (used) | 4,951 ft | May 12 | Oct 5 |
| Thiokol Propulsion F S, UT | 4,600 ft | May 17 | Sep 24 |
| Tremonton, UT | 4,310 ft | Apr 24 | Oct 17 |
| Cutler Dam, UT | 4,290 ft | May 3 | Oct 12 |
Frost dates near Howell
- Tremonton, UT 84337 · last Apr 24, first Oct 17
- Garland, UT 84312 · last Apr 24, first Oct 17
- Riverside, UT 84334 · last Apr 24, first Oct 17
- Fielding, UT 84311 · last May 3, first Oct 12
- Plymouth, UT 84330 · last May 3, first Oct 12
- Portage, UT 84331 · last May 22, first Sep 20
- Deweyville, UT 84309 · last Apr 24, first Oct 17
- Collinston, UT 84306 · last Apr 30, first Oct 16
Frequently asked questions
- When is the last frost in Howell, UT?
- For ZIP code 84316, the average last spring frost (32°F) is May 12, based on NOAA 1991-2020 climate normals for the Brigham City 28 Wnw, UT weather station. There is a 1-in-10 chance of a frost after June 8.
- When is the first frost in Howell, UT?
- The average first fall frost (32°F) is October 5. There is a 1-in-10 chance of frost by September 24, so tender plants are at risk from that point on.
- How long is the growing season in 84316?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 144 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.