Frost dates for 59067Rapelje, MT
The average last spring frost in Rapelje is May 24 and the average first fall frost is September 21, giving a typical growing season of about 116 days. Dates are based on NOAA 1991-2020 climate normals.
- Average last spring frost
- May 24
- Average first fall frost
- Sep 21
- Growing season
- 116 days
Safer after Jun 11 (1-in-10 risk)
Possible by Sep 4 (1-in-10 risk)
Last frost typically in 209 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 26 · Jun 8 · Jun 26 | Aug 21 · Sep 8 · Sep 23 | 88 days | 100% |
| Frost / freeze (32°F) | May 11 · May 24 · Jun 11 | Sep 4 · Sep 21 · Oct 4 | 116 days | 100% |
| Hard freeze (28°F) | Apr 28 · May 11 · May 25 | Sep 18 · Oct 2 · Oct 16 | 143 days | 100% |
Planting calendar for Rapelje
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 23 – Jun 29 |
| Tomatoes | Transplant outdoors | Jun 9 – Jun 1 |
| Peppers | Start seeds indoors | Apr 23 – May 24 |
| Peppers | Transplant outdoors | Jun 23 – Jul 24 |
| Eggplant | Start seeds indoors | May 10 – Jun 8 |
| Eggplant | Transplant outdoors | Jun 23 – Jul 24 |
| Cucumbers | Sow outdoors | Jun 23 – Jun 11 |
| Summer squash | Sow outdoors | Jun 9 – Jul 24 |
| Winter squash & pumpkins | Sow outdoors | Jun 23 – Jul 24 |
| Snap beans | Sow outdoors | Jun 9 – Jul 4 |
| Sweet corn | Sow outdoors | Jun 9 – Jun 1 |
| Watermelon & cantaloupe | Sow outdoors | Jun 23 – Jul 24 |
| Okra | Sow outdoors | Jun 16 – Jul 9 |
| Peas | Sow outdoors (spring) | Apr 23 – Jun 8 |
| Potatoes | Plant outdoors (spring) | Apr 23 – Jun 23 |
| Onions | Start seeds indoors (spring) | Mar 12 – Apr 8 |
| Onions | Transplant outdoors (spring) | May 10 – Jun 8 |
| Broccoli | Start seeds indoors (spring) | Apr 5 – May 9 |
| Broccoli | Transplant outdoors (spring) | May 10 – Jun 8 |
| Broccoli | Start seeds indoors (fall) | May 22 – Jun 1 |
| Broccoli | Transplant outdoors (fall) | Jun 21 – Jul 2 |
| Cabbage | Start seeds indoors (spring) | Mar 26 – Apr 23 |
| Cabbage | Transplant outdoors (spring) | Apr 23 – May 24 |
| Cabbage | Start seeds indoors (fall) | May 12 – Jun 11 |
| Cabbage | Transplant outdoors (fall) | Jun 11 – Jul 12 |
| Leaf lettuce | Sow outdoors (spring) | Apr 23 – Jul 9 |
| Leaf lettuce | Sow outdoors (fall) | Jun 11 – Jul 28 |
| Spinach | Sow outdoors (spring) | Apr 16 – May 30 |
| Spinach | Sow outdoors (fall) | Jun 28 – Aug 2 |
| Radishes | Sow outdoors (spring) | Apr 23 – Jun 13 |
| Radishes | Sow outdoors (fall) | Jun 11 – Aug 12 |
| Kale | Sow outdoors (spring) | May 10 – May 30 |
| Kale | Sow outdoors (fall) | Jun 4 – Jul 12 |
| Carrots | Sow outdoors (spring) | May 24 – Jul 9 |
| Carrots | Sow outdoors (fall) | May 12 – Jun 27 |
| Garlic | Plant outdoors (fall) | Sep 11 – Oct 12 |
Where these dates come from
ZIP code 59067 is matched to the NOAA station Rapelje, MT, 1.9 km away, at 4,068 ft elevation (36 ft lower than the ZIP code's center). Nearby stations for comparison:
| Station | Elevation | Avg last frost | Avg first frost |
|---|---|---|---|
| Rapelje, MT (used) | 4,068 ft | May 24 | Sep 21 |
| Gibson 2 Ne, MT | 4,444 ft | May 27 | Sep 18 |
| Ryegate, MT | 3,650 ft | May 17 | Sep 23 |
| Columbus, MT | 3,602 ft | May 27 | Sep 14 |
Frost dates near Rapelje
- Molt, MT 59057 · last May 24, first Sep 21
- Reed Point, MT 59069 · last May 24, first Sep 21
- Ryegate, MT 59074 · last May 17, first Sep 23
- Broadview, MT 59015 · last May 22, first Sep 15
- Columbus, MT 59019 · last May 27, first Sep 14
- Melville, MT 59055 · last Jun 9, first Sep 7
- Lavina, MT 59046 · last May 17, first Sep 23
- Acton, MT 59002 · last May 4, first Oct 7
Frequently asked questions
- When is the last frost in Rapelje, MT?
- For ZIP code 59067, the average last spring frost (32°F) is May 24, based on NOAA 1991-2020 climate normals for the Rapelje, MT weather station. There is a 1-in-10 chance of a frost after June 11.
- When is the first frost in Rapelje, MT?
- The average first fall frost (32°F) is September 21. 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 59067?
- In half of years, the frost-free season (between the last and first 32°F frost) is at least 116 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.