Frost dates for 86038Mormon Lake, AZ
The average last spring frost in Mormon Lake is June 1 and the average first fall frost is October 3, giving a typical growing season of about 124 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- Jun 1
- Average first fall frost
- Oct 3
- Growing season
- 124 days
Safer after Jun 13 (1-in-10 risk)
Possible by Sep 22 (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) | May 31 · Jun 11 · Jun 25 | Sep 11 · Sep 23 · Oct 4 | 102 days | 100% |
| Frost / freeze (32°F) | May 14 · Jun 1 · Jun 13 | Sep 22 · Oct 3 · Oct 16 | 124 days | 100% |
| Hard freeze (28°F) | Apr 28 · May 17 · Jun 3 | Oct 1 · Oct 14 · Oct 30 | 149 days | 100% |
Planting calendar for Mormon Lake
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 – Jun 13 |
| 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 23 |
| Summer squash | Sow outdoors | Jun 17 – Aug 1 |
| Winter squash & pumpkins | Sow outdoors | Jul 1 – Aug 1 |
| Snap beans | Sow outdoors | Jun 17 – Jul 16 |
| Sweet corn | Sow outdoors | Jun 17 – Jun 13 |
| 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) | Jun 3 – Jun 13 |
| Broccoli | Transplant outdoors (fall) | Jul 3 – Jul 14 |
| Cabbage | Start seeds indoors (spring) | Apr 3 – May 1 |
| Cabbage | Transplant outdoors (spring) | May 1 – Jun 1 |
| Cabbage | Start seeds indoors (fall) | May 24 – Jun 23 |
| Cabbage | Transplant outdoors (fall) | Jun 23 – Jul 24 |
| Leaf lettuce | Sow outdoors (spring) | May 1 – Jul 17 |
| Leaf lettuce | Sow outdoors (fall) | Jun 23 – Aug 9 |
| Spinach | Sow outdoors (spring) | Apr 24 – Jun 7 |
| Spinach | Sow outdoors (fall) | Jul 10 – Aug 14 |
| Radishes | Sow outdoors (spring) | May 1 – Jun 21 |
| Radishes | Sow outdoors (fall) | Jun 23 – Aug 24 |
| Kale | Sow outdoors (spring) | May 18 – Jun 7 |
| Kale | Sow outdoors (fall) | Jun 16 – Jul 24 |
| Carrots | Sow outdoors (spring) | Jun 1 – Jul 17 |
| Carrots | Sow outdoors (fall) | May 24 – Jul 9 |
| Garlic | Plant outdoors (fall) | Sep 23 – Oct 24 |
Where these dates come from
ZIP code 86038 is matched to the NOAA station Happy Jack Rs, AZ, 18.9 km away, at 7,480 ft elevation (334 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Happy Jack Rs, AZ (used) | 7,480 ft | Jun 1 | Oct 3 |
| Mund'S Park, AZ | 6,470 ft | Jun 10 | Sep 27 |
| Oak Creek Canyon, AZ | 5,118 ft | Apr 14 | Nov 5 |
| Sedona, AZ | 4,220 ft | Apr 1 | Nov 17 |
Frost dates near Mormon Lake
- Munds Park, AZ 86017 · last Jun 10, first Sep 27
- Sedona, AZ 86339 · last Apr 1, first Nov 17
- Happy Jack, AZ 86024 · last May 31, first Oct 2
- Flagstaff, AZ 86005 · last Jun 4, first Sep 28
- Lake Montezuma, AZ 86342 · last Apr 16, first Oct 30
- Rimrock, AZ 86335 · last Apr 16, first Oct 30
- Cornville, AZ 86325 · last Mar 30, first Nov 10
- Bellemont, AZ 86015 · last Jun 21, first Sep 17
Frequently asked questions
- When is the last frost in Mormon Lake, AZ?
- For ZIP code 86038, the average last spring frost (32°F) is June 1, based on NOAA 1991-2020 climate normals for the Happy Jack Rs, AZ weather station. There is a 1-in-10 chance of a frost after June 13.
- When is the first frost in Mormon Lake, AZ?
- The average first fall frost (32°F) is October 3. There is a 1-in-10 chance of frost by September 22, so tender plants are at risk from that point on.
- How long is the growing season in 86038?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 124 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.