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Will it freeze in Rigby in the next 7 nights?
The earliest overnight low at or below 32°F in the available NWS frost forecast is Tonight: 30°F (Thu, Nov 5, 6:00 PM MST to Fri, Nov 6, 6:00 AM MST).
Tonight: forecast low 30°F. Freeze.
NWS forecast period: Thu, Nov 5, 6:00 PM MST to Fri, Nov 6, 6:00 AM MST.
7 of the next 7 nights are forecast at 36°F or colder, cold enough for frost on exposed plants.
- Tonight 30°F Freeze · Patchy Fog
- Fri, Nov 6 29°F Freeze · Partly Cloudy
- Sat, Nov 7 31°F Freeze · Mostly Clear
- Sun, Nov 8 33°F Frost possible · Mostly Cloudy
- Mon, Nov 9 35°F Frost possible · Mostly Cloudy
- Tue, Nov 10 34°F Frost possible · Mostly Clear
- Wed, Nov 11 36°F Frost possible · Partly Cloudy
Overnight lows from the National Weather Service forecast for this location. This covers the available forecast window, not the first freeze of the whole season. Frost can form above 32°F on clear, calm nights.
Frost and freeze probabilities
Freeze dates shift from year to year. Spring percentages describe the chance of a freeze after the stated date; fall percentages describe the chance of a freeze by that date. The 10% spring date is the cautious one: a later freeze happens about 1 year in 10.
These dates describe historical probabilities, not this year’s forecast or the earliest and latest possible freezes. Different weather stations or probability thresholds can produce different published dates for the same city.
Average first hard freeze in Rigby
The median first fall hard-freeze date (28°F) is October 16, from NOAA’s 1991–2020 Climate Normals at Rigby. This is the 50% probability date, not a forecast for this year.
| Temperature | Last spring date 90% · 50% · 10% chance of a later freeze | First fall date 10% · 50% · 90% chance of an earlier freeze | Season |
|---|---|---|---|
| 36°F frost possible | May 10 · May 26 · Jun 14 | Sep 9 · Sep 24 · Oct 6 | 118 days |
| 32°F freeze | Apr 27 · May 9 · May 25 | Sep 21 · Oct 5 · Oct 18 | 148 days |
| 28°F hard freeze | Apr 12 · Apr 28 · May 11 | Oct 2 · Oct 16 · Oct 28 | 170 days |
Average high temperature by month
1991–2020 normals at Rigby
Average low temperature by month
Months with lows near or below freezing carry frost risk
Where these frost dates come from
The frost dates for Rigby, ID come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Rigby (station USC00107689, elevation 4,856 ft), 0.2 mi from Rigby. Local conditions (valleys, hilltops, distance to water, city heat) can shift frost dates by days or weeks. The hardiness zone is from the 2023 USDA Plant Hardiness Zone Map (USDA ARS and Oregon State University PRISM). See our methodology.
Frost dates near Rigby
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Rexburg, ID | 12 mi | May 12 | Sep 24 |
| Ammon, ID | 14 mi | May 9 | Oct 1 |
| Idaho Falls, ID | 14 mi | May 9 | Oct 1 |
| Shelley, ID | 23 mi | May 23 | Sep 20 |
| Blackfoot, ID | 40 mi | May 5 | Oct 3 |
| Chubbuck, ID | 58 mi | May 16 | Oct 2 |
| Jackson, WY | 58 mi | Jun 20 | Aug 31 |
| Pocatello, ID | 62 mi | May 2 | Oct 11 |
| Preston, ID | 109 mi | May 16 | Sep 28 |
| Rupert, ID | 115 mi | May 6 | Oct 6 |
Frequently asked questions
When is the last frost in Rigby?
On average, the last spring frost (32°F) in Rigby is around May 9. In about 1 year in 10 it comes after May 25, and in 9 years in 10 it comes after April 27.
When is the first frost in Rigby?
The first fall frost (32°F) usually arrives around October 5. There’s a 10% chance of a freeze by September 21 and a 90% chance by October 18.
Can it frost in Rigby after the last frost date?
Yes. Frost can form on clear, calm nights even when the air stays above 32°F. Temperatures of 36°F or lower, cold enough for frost on exposed plants, have a 50% chance of occurring after May 26.
What growing zone is Rigby?
Rigby is in USDA Plant Hardiness Zone 5b (average annual extreme minimum temperature −15 to −10°F), based on the 2023 USDA map for ZIP code 83442. See growing zones in Idaho.
More: all Idaho frost dates · Idaho growing zones · frost vs. freeze