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Will it freeze in Union in the next 7 nights?
No overnight lows at or below 32°F are forecast in Union during the next 7 nights in the available NWS frost forecast.
Tonight: forecast low 61°F. Above 36°F.
NWS forecast period: Thu, Nov 5, 6:00 PM EST to Fri, Nov 6, 6:00 AM EST.
No nights at or below 36°F in the National Weather Service forecast for the next 7 nights.
- Tonight 61°F Above 36°F · Chance Light Rain
- Fri, Nov 6 49°F Above 36°F · Mostly Clear
- Sat, Nov 7 40°F Above 36°F · Mostly Clear
- Sun, Nov 8 41°F Above 36°F · Mostly Clear
- Mon, Nov 9 40°F Above 36°F · Mostly Clear
- Tue, Nov 10 42°F Above 36°F · Partly Cloudy
- Wed, Nov 11 43°F Above 36°F · Mostly Clear
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 Union
The median first fall hard-freeze date (28°F) is November 9, from NOAA’s 1991–2020 Climate Normals at Union 8 S. 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 | Apr 3 · Apr 18 · May 4 | Oct 10 · Oct 22 · Nov 2 | 186 days |
| 32°F freeze | Mar 21 · Apr 6 · Apr 21 | Oct 17 · Oct 30 · Nov 12 | 207 days |
| 28°F hard freeze | Mar 6 · Mar 26 · Apr 11 | Oct 26 · Nov 9 · Nov 29 | 230 days |
Average high temperature by month
1991–2020 normals at Union 8 S
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 Union, SC come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: Union 8 S (station USC00388786, elevation 480 ft), 8.5 mi from Union. 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 Union
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Clinton, SC | 22 mi | Mar 29 | Nov 4 |
| Spartanburg, SC | 23 mi | Apr 8 | Nov 1 |
| Woodruff, SC | 24 mi | Mar 29 | Nov 5 |
| Chester, SC | 24 mi | Apr 3 | Nov 2 |
| Gaffney, SC | 24 mi | Apr 20 | Oct 24 |
| Laurens, SC | 27 mi | Apr 1 | Nov 5 |
| York, SC | 29 mi | Apr 1 | Nov 3 |
| Newberry, SC | 30 mi | Mar 31 | Nov 7 |
| Fountain Inn, SC | 33 mi | Mar 29 | Nov 5 |
| Lyman, SC | 34 mi | Mar 28 | Nov 7 |
Frequently asked questions
When is the last frost in Union?
On average, the last spring frost (32°F) in Union is around April 6. In about 1 year in 10 it comes after April 21, and in 9 years in 10 it comes after March 21.
When is the first frost in Union?
The first fall frost (32°F) usually arrives around October 30. There’s a 10% chance of a freeze by October 17 and a 90% chance by November 12.
Can it frost in Union 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 April 18.
What growing zone is Union?
Union is in USDA Plant Hardiness Zone 8a (average annual extreme minimum temperature 10 to 15°F), based on the 2023 USDA map for ZIP code 29379. See growing zones in South Carolina.
More: all South Carolina frost dates · South Carolina growing zones · frost vs. freeze