Frost dates for 85930Mcnary, AZ
The average last spring frost in Mcnary is May 20 and the average first fall frost is October 11, giving a typical growing season of about 142 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 20
- Average first fall frost
- Oct 11
- Growing season
- 142 days
Safer after Jun 4 (1-in-10 risk)
Possible by Sep 29 (1-in-10 risk)
Last frost typically in 205 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 19 · Jun 1 · Jun 12 | Sep 21 · Oct 2 · Oct 14 | 123 days | 100% |
| Frost / freeze (32°F) | May 5 · May 20 · Jun 4 | Sep 29 · Oct 11 · Oct 24 | 142 days | 100% |
| Hard freeze (28°F) | Apr 22 · May 6 · May 23 | Oct 7 · Oct 22 · Nov 6 | 167 days | 100% |
Planting calendar for Mcnary
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 19 – Jun 25 |
| Tomatoes | Transplant outdoors | Jun 5 – Jun 21 |
| Peppers | Start seeds indoors | Apr 19 – May 20 |
| Peppers | Transplant outdoors | Jun 19 – Jul 20 |
| Eggplant | Start seeds indoors | May 6 – Jun 4 |
| Eggplant | Transplant outdoors | Jun 19 – Jul 20 |
| Cucumbers | Sow outdoors | Jun 19 – Jul 1 |
| Summer squash | Sow outdoors | Jun 5 – Jul 20 |
| Winter squash & pumpkins | Sow outdoors | Jun 19 – Jul 20 |
| Snap beans | Sow outdoors | Jun 5 – Jul 24 |
| Sweet corn | Sow outdoors | Jun 5 – Jun 21 |
| Watermelon & cantaloupe | Sow outdoors | Jun 19 – Jul 20 |
| Okra | Sow outdoors | Jun 12 – Jul 5 |
| Peas | Sow outdoors (spring) | Apr 19 – Jun 4 |
| Potatoes | Plant outdoors (spring) | Apr 19 – Jun 19 |
| Onions | Start seeds indoors (spring) | Mar 8 – Apr 4 |
| Onions | Transplant outdoors (spring) | May 6 – Jun 4 |
| Broccoli | Start seeds indoors (spring) | Apr 1 – May 5 |
| Broccoli | Transplant outdoors (spring) | May 6 – Jun 4 |
| Broccoli | Start seeds indoors (fall) | Jun 11 – Jun 21 |
| Broccoli | Transplant outdoors (fall) | Jul 11 – Jul 22 |
| Cabbage | Start seeds indoors (spring) | Mar 22 – Apr 19 |
| Cabbage | Transplant outdoors (spring) | Apr 19 – May 20 |
| Cabbage | Start seeds indoors (fall) | Jun 1 – Jul 1 |
| Cabbage | Transplant outdoors (fall) | Jul 1 – Aug 1 |
| Leaf lettuce | Sow outdoors (spring) | Apr 19 – Jul 5 |
| Leaf lettuce | Sow outdoors (fall) | Jul 1 – Aug 17 |
| Spinach | Sow outdoors (spring) | Apr 12 – May 26 |
| Spinach | Sow outdoors (fall) | Jul 18 – Aug 22 |
| Radishes | Sow outdoors (spring) | Apr 19 – Jun 9 |
| Radishes | Sow outdoors (fall) | Jul 1 – Sep 1 |
| Kale | Sow outdoors (spring) | May 6 – May 26 |
| Kale | Sow outdoors (fall) | Jun 24 – Aug 1 |
| Carrots | Sow outdoors (spring) | May 20 – Jul 5 |
| Carrots | Sow outdoors (fall) | Jun 1 – Jul 17 |
| Garlic | Plant outdoors (fall) | Oct 1 – Nov 1 |
Where these dates come from
ZIP code 85930 is matched to the NOAA station Mc Nary 2N, AZ, 4.3 km away, at 7,340 ft elevation (17 ft higher than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Mc Nary 2N, AZ (used) | 7,340 ft | May 20 | Oct 11 |
| Pinetop 2E, AZ | 7,200 ft | May 22 | Oct 6 |
| Show Low Ap, AZ | 6,411 ft | May 5 | Oct 15 |
| Sunrise Mtn, AZ | 9,371 ft | Jun 18 | Sep 18 |
Frost dates near Mcnary
- Pinetop, AZ 85935 · last May 22, first Oct 6
- Lakeside, AZ 85929 · last May 5, first Oct 15
- Vernon, AZ 85940 · last May 22, first Oct 6
- Show Low, AZ 85901 · last May 5, first Oct 15
- Whiteriver, AZ 85941 · last May 16, first Oct 13
- Fort Apache, AZ 85926 · last May 16, first Oct 13
- Greer, AZ 85927 · last Jun 5, first Sep 29
- White Mountain Lake, AZ 85912 · last May 5, first Oct 15
Frequently asked questions
- When is the last frost in Mcnary, AZ?
- For ZIP code 85930, the average last spring frost (32°F) is May 20, based on NOAA 1991-2020 climate normals for the Mc Nary 2N, AZ weather station. There is a 1-in-10 chance of a frost after June 4.
- When is the first frost in Mcnary, AZ?
- The average first fall frost (32°F) is October 11. There is a 1-in-10 chance of frost by September 29, so tender plants are at risk from that point on.
- How long is the growing season in 85930?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 142 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.