San Antonio · December
Run in the morning.
Cool month: average high 66°F, low 48°F. Cool, runnable conditions throughout — morning still has the steadiest air and lightest wind.
Avg high / low
66° / 48°F
Humidity
70%
Rain days
11/mo
Wind
11 mph
What December feels like in San Antonio
Sunrise
08:21
Mid-month average
Sunset
18:38
Mid-month average
Time-of-day breakdown
Morning
Steady cool air, low wind, and good light. The standard runner window in most months.
Midday
Mild but UV and traffic peak. Workable if you don't mind shifting your pace.
Evening
Warm and runnable. Crowded routes but the air's typically calm.
What to wear running in San Antonio in December
The kit for December in San Antonio: a long-sleeve or light jacket for the first mile.
December vs the surrounding months
vs November
-4° avg high
-3 rain days
San Antonio in November →
December
66°F avg high
11 rain days
Best: morning
vs January
+2° avg high
0 rain days
San Antonio in January →
Frequently Asked Questions
What is the best time of day to run in San Antonio in December?+
Morning. Cool, runnable conditions throughout — morning still has the steadiest air and lightest wind.
What's the average temperature in San Antonio in December?+
Average high 66°F, average low 48°F.
How does December compare to surrounding months in San Antonio?+
Compared to November (avg high 70°F), December is cooler. Compared to January (avg high 63°F), December is warmer.
Does it rain often in San Antonio in December?+
Expect about 11 measurable rain days in December, on average.