Frost dates for 86502Chambers, AZ
The average last spring frost in Chambers is May 22 and the average first fall frost is October 8, giving a typical growing season of about 138 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 22
- Average first fall frost
- Oct 8
- Growing season
- 138 days
Safer after Jun 10 (1-in-10 risk)
Possible by Sep 25 (1-in-10 risk)
Last frost typically in 200 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 20 · Jun 4 · Jun 17 | Sep 17 · Oct 1 · Oct 13 | 117 days | 100% |
| Frost / freeze (32°F) | May 5 · May 22 · Jun 10 | Sep 25 · Oct 8 · Oct 22 | 138 days | 100% |
| Hard freeze (28°F) | Apr 21 · May 7 · May 31 | Sep 30 · Oct 17 · Nov 2 | 161 days | 100% |
Planting calendar for Chambers
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 21 – Jun 27 |
| Tomatoes | Transplant outdoors | Jun 7 – Jun 18 |
| Peppers | Start seeds indoors | Apr 21 – May 22 |
| Peppers | Transplant outdoors | Jun 21 – Jul 22 |
| Eggplant | Start seeds indoors | May 8 – Jun 6 |
| Eggplant | Transplant outdoors | Jun 21 – Jul 22 |
| Cucumbers | Sow outdoors | Jun 21 – Jun 28 |
| Summer squash | Sow outdoors | Jun 7 – Jul 22 |
| Winter squash & pumpkins | Sow outdoors | Jun 21 – Jul 22 |
| Snap beans | Sow outdoors | Jun 7 – Jul 21 |
| Sweet corn | Sow outdoors | Jun 7 – Jun 18 |
| Watermelon & cantaloupe | Sow outdoors | Jun 21 – Jul 22 |
| Okra | Sow outdoors | Jun 14 – Jul 7 |
| Peas | Sow outdoors (spring) | Apr 21 – Jun 6 |
| Potatoes | Plant outdoors (spring) | Apr 21 – Jun 21 |
| Onions | Start seeds indoors (spring) | Mar 10 – Apr 6 |
| Onions | Transplant outdoors (spring) | May 8 – Jun 6 |
| Broccoli | Start seeds indoors (spring) | Apr 3 – May 7 |
| Broccoli | Transplant outdoors (spring) | May 8 – Jun 6 |
| Broccoli | Start seeds indoors (fall) | Jun 8 – Jun 18 |
| Broccoli | Transplant outdoors (fall) | Jul 8 – Jul 19 |
| Cabbage | Start seeds indoors (spring) | Mar 24 – Apr 21 |
| Cabbage | Transplant outdoors (spring) | Apr 21 – May 22 |
| Cabbage | Start seeds indoors (fall) | May 29 – Jun 28 |
| Cabbage | Transplant outdoors (fall) | Jun 28 – Jul 29 |
| Leaf lettuce | Sow outdoors (spring) | Apr 21 – Jul 7 |
| Leaf lettuce | Sow outdoors (fall) | Jun 28 – Aug 14 |
| Spinach | Sow outdoors (spring) | Apr 14 – May 28 |
| Spinach | Sow outdoors (fall) | Jul 15 – Aug 19 |
| Radishes | Sow outdoors (spring) | Apr 21 – Jun 11 |
| Radishes | Sow outdoors (fall) | Jun 28 – Aug 29 |
| Kale | Sow outdoors (spring) | May 8 – May 28 |
| Kale | Sow outdoors (fall) | Jun 21 – Jul 29 |
| Carrots | Sow outdoors (spring) | May 22 – Jul 7 |
| Carrots | Sow outdoors (fall) | May 29 – Jul 14 |
| Garlic | Plant outdoors (fall) | Sep 28 – Oct 29 |
Where these dates come from
ZIP code 86502 is matched to the NOAA station Sanders, AZ, 18.3 km away, at 5,853 ft elevation (381 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Sanders, AZ (used) | 5,853 ft | May 22 | Oct 8 |
| Painted Desert Np, AZ | 5,760 ft | May 1 | Oct 20 |
| Ganado, AZ | 6,340 ft | May 15 | Oct 10 |
| Petrified Forest Np, AZ | 5,446 ft | May 4 | Oct 16 |
Frost dates near Chambers
- Petrified Forest Natl Pk, AZ 86028 · last May 22, first Oct 8
- Red Valley, AZ 86544 · last May 22, first Oct 8
- Sanders, AZ 86512 · last May 22, first Oct 8
- Houck, AZ 86506 · last May 22, first Oct 8
- Lupton, AZ 86508 · last May 31, first Sep 28
- Ganado, AZ 86505 · last May 15, first Oct 10
- Indian Wells, AZ 86031 · last May 1, first Oct 20
- Sun Valley, AZ 86029 · last Apr 22, first Oct 24
Frequently asked questions
- When is the last frost in Chambers, AZ?
- For ZIP code 86502, the average last spring frost (32°F) is May 22, based on NOAA 1991-2020 climate normals for the Sanders, AZ weather station. There is a 1-in-10 chance of a frost after June 10.
- When is the first frost in Chambers, AZ?
- The average first fall frost (32°F) is October 8. There is a 1-in-10 chance of frost by September 25, so tender plants are at risk from that point on.
- How long is the growing season in 86502?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 138 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.