Weather in San Antonio in July
United States · 20-year averages, July
A hard month. July asks something of you. Go in knowing what. Daytime highs average 35.9 °C and the afternoon is not negotiable — outdoor plans move to early morning or evening.
July ranks 12 of 12 — near the bottom of San Antonio's year. February is the month that works, and the swing between the two is 48 points, which is a different holiday rather than a slightly better one.
Rain on 9 days, 2 of them heavy. Enough to need a plan B, not enough to need a plan around it. Pack for heat management rather than style: shade, water, and a schedule that gives up on the middle of the day.
What the averages hide
Averages flatten a month, and this one hides a few things: 20 days of the month clear 35 °C — that is not a heatwave, it is the month. Across the twenty years measured, the hottest July day reached 44.1 °C and the coldest night fell to 18.7 °C, and the wettest single day dropped 62 mm — roughly 87% of the month's rain in one day.
This is the volatile part. July rainfall has ranged from 4 mm to 289 mm across the twenty years measured — a 285 mm spread around an average of 71 mm. The average is real but almost no individual July looks like it, so treat the figure as the middle of a wide range rather than a forecast.
Wind is light at 10 km/h, so the temperature on the page is close to the temperature on your skin, and humidity is unremarkable at 65%.
How July sits in the year
Temperatures hold steady either side: 35.2 °C in June, 35.9 here, 36.7 in August. Nothing about the timing within the month matters much.
Daylight in July
July is at or near the longest days of San Antonio's year: 13.9 hours of daylight, losing 0.4 hours across the month. Evenings are the real gain — dinner outdoors still happens in full light.
An inland climate
With no coast nearby, the year swings a fair way — 31.5 °C between the warmest afternoons and the coldest nights, wider than any coastal city at this latitude would manage.
How busy it gets
Off season. The genuine off season: cheapest by a distance, with the caveat that some tours and restaurants close entirely.
Crowd levels are estimated from climate desirability and school-holiday calendars, not from visitor numbers.
July in San Antonio versus nearby
If San Antonio is one option among several, the nearby comparison is worth making. Corpus Christi is close enough to be a coin toss — within a degree on temperature, 1 day more rain. Laredo is close enough to be a coin toss — within a degree on temperature, 1 day less rain.
So: July is a compromise. February is 48 points better and is what San Antonio is actually like at its best — worth moving the trip for if that is possible, and worth adjusting expectations for if it is not.
Every month in San Antonio
| Month | High °C | Low °C | Rain days | Rain mm | Humidity % | Daylight h | Score |
|---|---|---|---|---|---|---|---|
| January | 17.7 | 5.2 | 6 | 49 | 70 | 10.4 | 80 |
| February | 20.4 | 7 | 5 | 36 | 70 | 11.1 | 91 |
| March | 24.7 | 11.2 | 7 | 62 | 70 | 11.9 | 86 |
| April | 29.1 | 15.2 | 6 | 62 | 66 | 12.9 | 78 |
| May | 32.3 | 19.7 | 10 | 100 | 68 | 13.6 | 56 |
| June | 35.2 | 23.1 | 10 | 71 | 65 | 14 | 44 |
| July | 35.9 | 24 | 9 | 71 | 65 | 13.9 | 43 |
| August | 36.7 | 24.6 | 7 | 62 | 61 | 13.2 | 44 |
| September | 32.8 | 21.6 | 10 | 95 | 68 | 12.4 | 54 |
| October | 28.9 | 16.2 | 7 | 79 | 68 | 11.5 | 77 |
| November | 23.2 | 10.8 | 5 | 49 | 70 | 10.7 | 91 |
| December | 18.7 | 6.2 | 6 | 45 | 69 | 10.3 | 83 |
See all twelve months in San Antonio, or where else to go in July.
Planning the rest of the trip
- Flight time to San Antonio how long you are actually in the air
- San Antonio time zone and the difference from home
- Days until your trip count down to the departure date
- Gyms & clubs in San Antonio keep training while you are there