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Will it freeze in Grantsville in the next 7 nights?
No overnight lows at or below 32°F are forecast in Grantsville during the next 7 nights in the available NWS frost forecast.
Tonight: forecast low 37°F. Above 36°F.
NWS forecast period: Thu, Nov 5, 6:00 PM MST to Fri, Nov 6, 6:00 AM MST.
1 of the next 7 nights are forecast at 36°F or colder, cold enough for frost on exposed plants.
- Tonight 37°F Above 36°F · Partly Cloudy
- Fri, Nov 6 36°F Frost possible · Mostly Clear
- Sat, Nov 7 39°F Above 36°F · Mostly Clear
- Sun, Nov 8 42°F Above 36°F · Mostly Clear
- Mon, Nov 9 43°F Above 36°F · Mostly Cloudy
- Tue, Nov 10 42°F Above 36°F · Partly Cloudy
- Wed, Nov 11 43°F Above 36°F · 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 Grantsville
The median first fall hard-freeze date (28°F) is October 25, from NOAA’s 1991–2020 Climate Normals at Grantsville 2W. 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 1 · May 16 · Jun 5 | Sep 21 · Oct 4 · Oct 17 | 140 days |
| 32°F freeze | Apr 17 · May 2 · May 19 | Sep 30 · Oct 14 · Oct 27 | 164 days |
| 28°F hard freeze | Mar 31 · Apr 17 · May 5 | Oct 8 · Oct 25 · Nov 8 | 189 days |
Average high temperature by month
1991–2020 normals at Grantsville 2W
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 Grantsville, UT come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Grantsville 2W (station USC00423348, elevation 4,550 ft), 2.1 mi from Grantsville. 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 Grantsville
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Tooele, UT | 9.9 mi | May 2 | Oct 16 |
| Magna, UT | 18 mi | Apr 3 | Nov 4 |
| Kearns, UT | 24 mi | Apr 8 | Oct 31 |
| West Jordan, UT | 25 mi | Apr 18 | Oct 22 |
| West Valley City, UT | 25 mi | Apr 8 | Oct 31 |
| Herriman, UT | 25 mi | Apr 18 | Oct 22 |
| South Jordan, UT | 25 mi | Apr 18 | Oct 22 |
| Riverton, UT | 27 mi | Apr 18 | Oct 22 |
| Taylorsville, UT | 27 mi | Mar 31 | Nov 8 |
| Bluffdale, UT | 29 mi | Apr 18 | Oct 22 |
Frequently asked questions
When is the last frost in Grantsville?
On average, the last spring frost (32°F) in Grantsville is around May 2. In about 1 year in 10 it comes after May 19, and in 9 years in 10 it comes after April 17.
When is the first frost in Grantsville?
The first fall frost (32°F) usually arrives around October 14. There’s a 10% chance of a freeze by September 30 and a 90% chance by October 27.
Can it frost in Grantsville 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 16.
What growing zone is Grantsville?
Grantsville is in USDA Plant Hardiness Zone 7a (average annual extreme minimum temperature 0 to 5°F), based on the 2023 USDA map for ZIP code 84074. See growing zones in Utah.
More: all Utah frost dates · Utah growing zones · frost vs. freeze