San Antonio weather in December

Regulars are blunt that Texas weather doesn't make up its mind until close to the trip itself, with swings from the upper 70s one day to the upper 30s just two days later well within normal range for this month. Our row backs the mild average sitting between those extremes, 20.7C over 7.3C nights feeling 5C, with 47.6mm of rain across 4.6 days. Regulars are consistent the standard packing answer is simply everything - shorts and short sleeves for a warm afternoon, a real jacket for a cold snap - checking the forecast close to departure rather than trusting any single seasonal average. Snow is essentially a non-issue here, regulars call it a rare novelty rather than a planning concern. Visiting after Thanksgiving means catching the River Walk's holiday lights, a genuine seasonal highlight regulars are quick to recommend. The record: humidity 69 percent, 6.4 hours of sun, a 17.1 kph wind and AQI 31.

Regulars call this the best stretch of the year here, past the nasty summer highs but still genuinely shorts weather right up to around Halloween, with the caveat that an incoming cold front can swing a given day anywhere from the 40s to the 90s Fahrenheit. Our row backs the warm-but-cooling read, 29.3C reading as 30C over 16.5C nights, with 54.3mm of rain across 4.9 days. Regulars specifically steer outdoor-pool plans toward September instead, since by this point a cold front can make an afternoon swim genuinely too chilly to enjoy even on an otherwise warm-looking day. The record: humidity 63 percent, 9.3 hours of sun, a 16.3 kph wind and one of the cleanest air readings in this project, AQI 37.

March and April are the two months regulars name for this city - flowers and trees in bloom, wildflowers at their best in late March and early April, and weather they call perfect - and then they cut the month in half. The last two weeks are Fiesta, a city-wide event drawing something like two and a half million people, and the Riverwalk sidewalks are congested throughout it. Anyone who dislikes crowds books the first fortnight; anyone who came for the event books the second. The Riverwalk itself stays shaded and comfortable year-round. Our row: 28C days over 15.5C nights, 72mm across 5.8 days, 8.9 hours of sun and a 20.2 kph wind.

November is the month San Antonio regulars call perfect - sunny, pleasant, the trees turning, and mornings in the low 50s Fahrenheit warming into the middle and upper 70s. Our row's 22.5C day over a 10.2C night is that spread. They rate it above mid-September and above early October, which can still be genuinely hot. The caveat is the standing Texas one: the month can equally deliver 40s, so layers and a jacket for the early morning and the evening. The other November note is the calendar - the holiday lights go on in the middle of the month, and several regulars push visitors one month further to early December for the same weather plus the full display. The record: 5 precipitation days carrying 42.1mm, humidity 69 percent and 7.1 hours of sun.

San Antonio forum threads describe January as genuinely unpredictable, with a typical high around 62F and low near 39F, but posters were direct that the same week could bring sunny days in the 70s or, on the harder end, sub-freezing temperatures with sleet, snow and icy roads. Posters were consistent there's no reliable way to forecast which way a given January week will go this far ahead, so flexibility was the recurring theme. On the upside, January was flagged as the city's slowest tourist month, meaning fewer crowds along the River Walk and other main attractions - several posters specifically recommended it for anyone comfortable packing for both a warm and a genuinely cold scenario.