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Will it freeze in San Marcos in the next 7 nights?
No overnight lows at or below 32°F are forecast in San Marcos during the next 7 nights in the available NWS frost forecast.
Tonight: forecast low 57°F. Above 36°F.
NWS forecast period: Thu, Nov 5, 6:00 PM CST to Fri, Nov 6, 6:00 AM CST.
No nights at or below 36°F in the National Weather Service forecast for the next 7 nights.
- Tonight 57°F Above 36°F · Partly Cloudy
- Fri, Nov 6 56°F Above 36°F · Partly Cloudy
- Sat, Nov 7 54°F Above 36°F · Showers And Thunderstorms Likely
- Sun, Nov 8 49°F Above 36°F · Chance Rain Showers
- Mon, Nov 9 50°F Above 36°F · Slight Chance Rain Showers then Partly Cloudy
- Tue, Nov 10 52°F Above 36°F · Partly Cloudy
- Wed, Nov 11 54°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 San Marcos
The median first fall hard-freeze date (28°F) is December 15, from NOAA’s 1991–2020 Climate Normals at San Marcos. 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 | Feb 23 · Mar 14 · Apr 5 | Nov 1 · Nov 16 · Dec 4 | 246 days |
| 32°F freeze | Feb 1 · Feb 28 · Mar 21 | Nov 8 · Nov 29 · Dec 21 | 273 days |
| 28°F hard freeze | Jan 9 · Feb 13 · Mar 8 | Nov 19 · Dec 15 · Jan 13 | 306 days |
Average high temperature by month
1991–2020 normals at San Marcos
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 San Marcos, TX come from the nearest weather station with freeze statistics in NOAA’s 1991–2020 Climate Normals: San Marcos (station USC00417983, elevation 665 ft), 1.0 mi from San Marcos. 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 San Marcos
| City | Distance | Last spring frost | First fall frost |
|---|---|---|---|
| Kyle, TX | 8.7 mi | Feb 28 | Nov 29 |
| Buda, TX | 15 mi | Mar 10 | Nov 17 |
| Lockhart, TX | 16 mi | Mar 5 | Nov 23 |
| New Braunfels, TX | 16 mi | Mar 8 | Nov 18 |
| Seguin, TX | 20 mi | Mar 1 | Nov 26 |
| Luling, TX | 22 mi | Mar 5 | Nov 23 |
| Dripping Springs, TX | 24 mi | Mar 17 | Nov 13 |
| Cibolo, TX | 27 mi | Feb 21 | Dec 5 |
| Schertz, TX | 29 mi | Feb 21 | Dec 5 |
| Bee Cave, TX | 30 mi | Mar 17 | Nov 13 |
Frequently asked questions
When is the last frost in San Marcos?
On average, the last spring frost (32°F) in San Marcos is around February 28. In about 1 year in 10 it comes after March 21, and in 9 years in 10 it comes after February 1.
When is the first frost in San Marcos?
The first fall frost (32°F) usually arrives around November 29. There’s a 10% chance of a freeze by November 8 and a 90% chance by December 21.
Can it frost in San Marcos 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 March 14.
What growing zone is San Marcos?
San Marcos is in USDA Plant Hardiness Zone 9a (average annual extreme minimum temperature 20 to 25°F), based on the 2023 USDA map for ZIP code 78666. See growing zones in Texas.
More: all Texas frost dates · Texas growing zones · UV index today in San Marcos · frost vs. freeze