San Marcos weather in July
In July, San Marcos sees average daytime highs of 94°F and overnight lows near 74°F, with 1.8 in of rain across 6.4 wet days and about 13.7 hours of daylight. It is the 2nd-warmest and 12th-wettest month of the year here.
Highs climb over the month, from about 92°F in the first days to 95°F by the end. The sky is clear or mostly clear about 49% of the time in July, and the air most often feels oppressive.
Daylight stretches from about 13 h 54 min at the start of July to 13 h 30 min by month's end. Set against the rest of the year, July is San Marcos's 4th-clearest and 9th-windiest month. For the whole year in context, see San Marcos's year-round climate.
- Daytime high
- 94°
- 2nd warmest
- Overnight low
- 74°
- 12th coldest
- Rainfall
- 1.8 in
- 6.4 wet days
- Daylight
- 13 h 42 min
- 5:45 AM – 7:30 PM
- Cloud cover
- 47%
- 4th clearest
- Wind
- 7 mph
- 9th windiest
- Solar energy
- 6.69 kWh/m²
- Travel score
- 3.2
- out of 10
San Marcos is city in and county seat of Hays County, Texas, United States, that extends into Caldwell and Guadalupe counties.
- Density
- 684/km²
- people per km²
- Founded
- 1808
Air quality: WHO Ambient Air Quality Database. Density & description: Wikidata (CC0), GeoNames.
Temperature in July
Highs climb over the month, from about 92°F in the first days to 95°F by the end.
A typical July day in San Marcos reaches about 94°F in the afternoon and slips back to 74°F overnight — a 20°F spread between the day's warmth and the night's chill. On most days the high lands between 88°F and 99°F. Set against its neighbours, July runs about 3°F warmer than June and on par with August.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Avg high (°F) | 92 | 92 | 92 | 92 | 92 | 92 | 92 | 93 | 93 | 93 | 93 | 93 | 93 | 94 | 94 | 94 | 94 | 94 | 94 | 94 | 94 | 94 | 94 | 94 | 95 | 95 | 95 | 95 | 95 | 95 | 95 |
| Avg low (°F) | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 | 74 |
| Avg high (°F) | Avg low (°F) | |
|---|---|---|
| 1 | 92 | 74 |
| 2 | 92 | 74 |
| 3 | 92 | 74 |
| 4 | 92 | 74 |
| 5 | 92 | 74 |
| 6 | 92 | 74 |
| 7 | 92 | 74 |
| 8 | 93 | 74 |
| 9 | 93 | 74 |
| 10 | 93 | 74 |
| 11 | 93 | 74 |
| 12 | 93 | 74 |
| 13 | 93 | 74 |
| 14 | 94 | 74 |
| 15 | 94 | 74 |
| 16 | 94 | 74 |
| 17 | 94 | 74 |
| 18 | 94 | 74 |
| 19 | 94 | 74 |
| 20 | 94 | 74 |
| 21 | 94 | 74 |
| 22 | 94 | 74 |
| 23 | 94 | 74 |
| 24 | 94 | 74 |
| 25 | 95 | 74 |
| 26 | 95 | 74 |
| 27 | 95 | 74 |
| 28 | 95 | 74 |
| 29 | 95 | 74 |
| 30 | 95 | 74 |
| 31 | 95 | 74 |
How July really feels in San Marcos
Once humidity and wind are folded in, July averages 31 days that feel above 90°F and 0 that feel at or below 32°F — the comfort signal a plain temperature reading hides.
The story in July is heat — humidity pushes the afternoon "feels like" well above the raw temperature.
San Marcos weather by month
How July compares with the rest of the year at a glance. July is the 2nd-warmest and 12th-wettest month here — the current month is highlighted below.
| Month | High / Low (°F) | Rainfall (inches) | Wet days | Daylight (hours) | Travel score |
|---|---|---|---|---|---|
| Jan | 61° / 42° | 2.5 | 7.4 | 10.3 | 5.4 |
| Feb | 65° / 46° | 2.4 | 7.6 | 10.9 | 6.2 |
| Mar | 71° / 52° | 3.0 | 9.4 | 11.8 | 6.8 |
| Apr | 78° / 59° | 3.3 | 9 | 12.7 | 6.9 |
| May | 85° / 66° | 4.5 | 11.4 | 13.5 | 5.3 |
| Jun | 90° / 72° | 3.2 | 9.8 | 13.9 | 3.9 |
| Jul | 94° / 74° | 1.8 | 6.4 | 13.7 | 3.2 |
| Aug | 94° / 74° | 2.4 | 6.4 | 13.1 | 3.0 |
| Sep | 88° / 69° | 3.0 | 8.2 | 12.2 | 4.7 |
| Oct | 80° / 60° | 3.2 | 7.5 | 11.3 | 7.1 |
| Nov | 69° / 50° | 2.8 | 7 | 10.5 | 7.0 |
| Dec | 62° / 43° | 2.8 | 7.9 | 10.1 | 5.7 |
Cloud cover in July
The sky is clear or mostly clear about 49% of the time in July.
Beyond those clear spells, partly cloudy skies cover about 18% of July, with mostly cloudy or overcast conditions the remaining 33%. Skies tend to open up as the month goes on.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Clearer (%) | 65 | 65 | 66 | 66 | 66 | 66 | 66 | 67 | 68 | 68 | 68 | 68 | 69 | 68 | 68 | 68 | 68 | 68 | 68 | 67 | 67 | 67 | 67 | 67 | 67 | 67 | 67 | 69 | 69 | 69 | 71 |
| Cloudier (%) | 35 | 35 | 34 | 34 | 34 | 34 | 34 | 33 | 32 | 32 | 32 | 32 | 31 | 32 | 32 | 32 | 32 | 32 | 32 | 33 | 33 | 33 | 33 | 33 | 33 | 33 | 33 | 31 | 31 | 31 | 29 |
| Clearer (%) | Cloudier (%) | |
|---|---|---|
| 1 | 65 | 35 |
| 2 | 65 | 35 |
| 3 | 66 | 34 |
| 4 | 66 | 34 |
| 5 | 66 | 34 |
| 6 | 66 | 34 |
| 7 | 66 | 34 |
| 8 | 67 | 33 |
| 9 | 68 | 32 |
| 10 | 68 | 32 |
| 11 | 68 | 32 |
| 12 | 68 | 32 |
| 13 | 69 | 31 |
| 14 | 68 | 32 |
| 15 | 68 | 32 |
| 16 | 68 | 32 |
| 17 | 68 | 32 |
| 18 | 68 | 32 |
| 19 | 68 | 32 |
| 20 | 67 | 33 |
| 21 | 67 | 33 |
| 22 | 67 | 33 |
| 23 | 67 | 33 |
| 24 | 67 | 33 |
| 25 | 67 | 33 |
| 26 | 67 | 33 |
| 27 | 67 | 33 |
| 28 | 69 | 31 |
| 29 | 69 | 31 |
| 30 | 69 | 31 |
| 31 | 71 | 29 |
Chance of precipitation in July
San Marcos gets around 1.8 in of rain over 6.4 wet days in July, the driest month. The line is the day-by-day chance of measurable precipitation.
Day to day, the chance of measurable rain averages around 21% and peaks near 32% on the wettest days. The odds ease toward the end of the month.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rain chance (%) | 32 | 31 | 30 | 29 | 28 | 26 | 25 | 25 | 24 | 23 | 22 | 21 | 20 | 19 | 19 | 18 | 18 | 17 | 17 | 17 | 17 | 17 | 17 | 16 | 16 | 16 | 16 | 15 | 15 | 15 | 15 |
| Rain chance (%) | |
|---|---|
| 1 | 32 |
| 2 | 31 |
| 3 | 30 |
| 4 | 29 |
| 5 | 28 |
| 6 | 26 |
| 7 | 25 |
| 8 | 25 |
| 9 | 24 |
| 10 | 23 |
| 11 | 22 |
| 12 | 21 |
| 13 | 20 |
| 14 | 19 |
| 15 | 19 |
| 16 | 18 |
| 17 | 18 |
| 18 | 17 |
| 19 | 17 |
| 20 | 17 |
| 21 | 17 |
| 22 | 17 |
| 23 | 17 |
| 24 | 16 |
| 25 | 16 |
| 26 | 16 |
| 27 | 16 |
| 28 | 15 |
| 29 | 15 |
| 30 | 15 |
| 31 | 15 |
Humidity in July
Most of July feels oppressive — the stacked bands show each day's mix of comfort levels, read off the dew point.
By dew point, July lands in the oppressive band about 48% of days. Sticky, muggy-or-worse air turns up on roughly 92% of them.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Dry (%) | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| Comfortable (%) | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 2 | 2 | 2 | 2 | 2 | 1 |
| Humid (%) | 6 | 6 | 6 | 6 | 6 | 6 | 6 | 6 | 6 | 6 | 6 | 6 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 8 | 8 | 8 | 8 | 8 | 8 | 8 | 8 |
| Muggy (%) | 33 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | 45 | 46 | 47 | 47 | 47 | 47 | 48 | 48 | 48 | 48 | 48 | 49 | 49 | 50 | 51 | 52 | 53 |
| Oppressive (%) | 58 | 58 | 57 | 56 | 55 | 54 | 54 | 53 | 53 | 53 | 52 | 51 | 49 | 48 | 47 | 46 | 46 | 45 | 45 | 44 | 44 | 44 | 43 | 43 | 42 | 41 | 40 | 39 | 38 | 37 | 37 |
| Miserable (%) | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Dry (%) | Comfortable (%) | Humid (%) | Muggy (%) | Oppressive (%) | Miserable (%) | |
|---|---|---|---|---|---|---|
| 1 | 1 | 1 | 6 | 33 | 58 | 1 |
| 2 | 1 | 1 | 6 | 33 | 58 | 1 |
| 3 | 1 | 1 | 6 | 34 | 57 | 1 |
| 4 | 1 | 1 | 6 | 35 | 56 | 1 |
| 5 | 1 | 1 | 6 | 36 | 55 | 1 |
| 6 | 1 | 1 | 6 | 37 | 54 | 1 |
| 7 | 1 | 0 | 6 | 38 | 54 | 1 |
| 8 | 1 | 0 | 6 | 39 | 53 | 1 |
| 9 | 0 | 0 | 6 | 40 | 53 | 1 |
| 10 | 0 | 0 | 6 | 41 | 53 | 0 |
| 11 | 0 | 0 | 6 | 42 | 52 | 0 |
| 12 | 0 | 0 | 6 | 43 | 51 | 0 |
| 13 | 0 | 0 | 7 | 44 | 49 | 0 |
| 14 | 0 | 0 | 7 | 45 | 48 | 0 |
| 15 | 0 | 0 | 7 | 45 | 47 | 0 |
| 16 | 0 | 0 | 7 | 46 | 46 | 0 |
| 17 | 0 | 0 | 7 | 47 | 46 | 0 |
| 18 | 0 | 1 | 7 | 47 | 45 | 0 |
| 19 | 0 | 1 | 7 | 47 | 45 | 0 |
| 20 | 0 | 1 | 7 | 47 | 44 | 0 |
| 21 | 1 | 1 | 7 | 48 | 44 | 0 |
| 22 | 1 | 1 | 7 | 48 | 44 | 0 |
| 23 | 1 | 1 | 7 | 48 | 43 | 0 |
| 24 | 1 | 1 | 8 | 48 | 43 | 0 |
| 25 | 1 | 1 | 8 | 48 | 42 | 0 |
| 26 | 1 | 2 | 8 | 49 | 41 | 0 |
| 27 | 1 | 2 | 8 | 49 | 40 | 0 |
| 28 | 1 | 2 | 8 | 50 | 39 | 0 |
| 29 | 1 | 2 | 8 | 51 | 38 | 0 |
| 30 | 1 | 2 | 8 | 52 | 37 | 0 |
| 31 | 1 | 1 | 8 | 53 | 37 | 0 |
Wind in July
Winds average 7 mph in July.
Across July, daily wind ranges from about 7 mph on the calmest days to 7 mph at its breeziest. It stays fairly steady from day to day.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Wind speed (mph) | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 | 7 |
| Feels | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm | calm |
| Wind speed (mph) | Feels | |
|---|---|---|
| 1 | 7 | calm |
| 2 | 7 | calm |
| 3 | 7 | calm |
| 4 | 7 | calm |
| 5 | 7 | calm |
| 6 | 7 | calm |
| 7 | 7 | calm |
| 8 | 7 | calm |
| 9 | 7 | calm |
| 10 | 7 | calm |
| 11 | 7 | calm |
| 12 | 7 | calm |
| 13 | 7 | calm |
| 14 | 7 | calm |
| 15 | 7 | calm |
| 16 | 7 | calm |
| 17 | 7 | calm |
| 18 | 7 | calm |
| 19 | 7 | calm |
| 20 | 7 | calm |
| 21 | 7 | calm |
| 22 | 7 | calm |
| 23 | 7 | calm |
| 24 | 7 | calm |
| 25 | 7 | calm |
| 26 | 7 | calm |
| 27 | 7 | calm |
| 28 | 7 | calm |
| 29 | 7 | calm |
| 30 | 7 | calm |
| 31 | 7 | calm |
Sunrise & sunset in July
Daylight runs from about 13 h 54 min at the start of July to 13 h 30 min by month's end. The lit band spans sunrise to sunset each day.
Days shrink by about 24 minutes over July. Sunrise moves from 5:38 AM to 5:54 AM, and sunset from 7:32 PM to 7:22 PM.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Daylight (h) | 13.9 | 13.9 | 13.9 | 13.9 | 13.9 | 13.9 | 13.9 | 13.8 | 13.8 | 13.8 | 13.8 | 13.8 | 13.8 | 13.8 | 13.8 | 13.7 | 13.7 | 13.7 | 13.7 | 13.7 | 13.7 | 13.7 | 13.6 | 13.6 | 13.6 | 13.6 | 13.6 | 13.5 | 13.5 | 13.5 | 13.5 |
| Sunrise (AM) | 5:38 | 5:38 | 5:39 | 5:39 | 5:40 | 5:40 | 5:41 | 5:41 | 5:41 | 5:42 | 5:42 | 5:43 | 5:43 | 5:44 | 5:44 | 5:45 | 5:45 | 5:46 | 5:47 | 5:47 | 5:48 | 5:48 | 5:49 | 5:49 | 5:50 | 5:51 | 5:51 | 5:52 | 5:52 | 5:53 | 5:54 |
| Sunset (PM) | 7:32 | 7:32 | 7:32 | 7:32 | 7:32 | 7:32 | 7:32 | 7:32 | 7:32 | 7:31 | 7:31 | 7:31 | 7:31 | 7:30 | 7:30 | 7:30 | 7:29 | 7:29 | 7:29 | 7:28 | 7:28 | 7:27 | 7:27 | 7:26 | 7:26 | 7:25 | 7:25 | 7:24 | 7:23 | 7:23 | 7:22 |
| Daylight (h) | Sunrise (AM) | Sunset (PM) | |
|---|---|---|---|
| 1 | 13.9 | 5:38 | 7:32 |
| 2 | 13.9 | 5:38 | 7:32 |
| 3 | 13.9 | 5:39 | 7:32 |
| 4 | 13.9 | 5:39 | 7:32 |
| 5 | 13.9 | 5:40 | 7:32 |
| 6 | 13.9 | 5:40 | 7:32 |
| 7 | 13.9 | 5:41 | 7:32 |
| 8 | 13.8 | 5:41 | 7:32 |
| 9 | 13.8 | 5:41 | 7:32 |
| 10 | 13.8 | 5:42 | 7:31 |
| 11 | 13.8 | 5:42 | 7:31 |
| 12 | 13.8 | 5:43 | 7:31 |
| 13 | 13.8 | 5:43 | 7:31 |
| 14 | 13.8 | 5:44 | 7:30 |
| 15 | 13.8 | 5:44 | 7:30 |
| 16 | 13.7 | 5:45 | 7:30 |
| 17 | 13.7 | 5:45 | 7:29 |
| 18 | 13.7 | 5:46 | 7:29 |
| 19 | 13.7 | 5:47 | 7:29 |
| 20 | 13.7 | 5:47 | 7:28 |
| 21 | 13.7 | 5:48 | 7:28 |
| 22 | 13.7 | 5:48 | 7:27 |
| 23 | 13.6 | 5:49 | 7:27 |
| 24 | 13.6 | 5:49 | 7:26 |
| 25 | 13.6 | 5:50 | 7:26 |
| 26 | 13.6 | 5:51 | 7:25 |
| 27 | 13.6 | 5:51 | 7:25 |
| 28 | 13.5 | 5:52 | 7:24 |
| 29 | 13.5 | 5:52 | 7:23 |
| 30 | 13.5 | 5:53 | 7:23 |
| 31 | 13.5 | 5:54 | 7:22 |
Solar energy in July
Average shortwave solar energy reaching the ground each day in July, about 6.69 kWh/m² — the sunniest month for solar.
For context, solar energy here swings from a low near 2.69 kWh/m² to a high of 6.69 kWh/m² in July across the year — July's 6.69 kWh/m² sits near the top of that range.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Solar energy (kWh/m²) | 6.4 | 6.4 | 6.5 | 6.5 | 6.5 | 6.5 | 6.6 | 6.6 | 6.6 | 6.6 | 6.7 | 6.7 | 6.7 | 6.7 | 6.7 | 6.7 | 6.7 | 6.8 | 6.8 | 6.8 | 6.8 | 6.8 | 6.8 | 6.8 | 6.8 | 6.8 | 6.8 | 6.8 | 6.7 | 6.7 | 6.7 |
| Level | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense | Intense |
| Solar energy (kWh/m²) | Level | |
|---|---|---|
| 1 | 6.4 | Intense |
| 2 | 6.4 | Intense |
| 3 | 6.5 | Intense |
| 4 | 6.5 | Intense |
| 5 | 6.5 | Intense |
| 6 | 6.5 | Intense |
| 7 | 6.6 | Intense |
| 8 | 6.6 | Intense |
| 9 | 6.6 | Intense |
| 10 | 6.6 | Intense |
| 11 | 6.7 | Intense |
| 12 | 6.7 | Intense |
| 13 | 6.7 | Intense |
| 14 | 6.7 | Intense |
| 15 | 6.7 | Intense |
| 16 | 6.7 | Intense |
| 17 | 6.7 | Intense |
| 18 | 6.8 | Intense |
| 19 | 6.8 | Intense |
| 20 | 6.8 | Intense |
| 21 | 6.8 | Intense |
| 22 | 6.8 | Intense |
| 23 | 6.8 | Intense |
| 24 | 6.8 | Intense |
| 25 | 6.8 | Intense |
| 26 | 6.8 | Intense |
| 27 | 6.8 | Intense |
| 28 | 6.8 | Intense |
| 29 | 6.7 | Intense |
| 30 | 6.7 | Intense |
| 31 | 6.7 | Intense |
Is July a good time to visit San Marcos?
Our two travel scores rate July for general sightseeing and for beach or pool weather — 0 (poor) to 10 (ideal).
July is a weaker month for outdoor sightseeing in San Marcos. The water and warmth also suit a beach or pool day.
What to pack for San Marcos in July
From July's temperature range, rain chance, sun and wind — what's worth putting in the bag.
In July, San Marcos sees daytime highs around 94°F and nights near 74°F. Pack light clothes and sun protection. About 6 days see rain.
UV index in San Marcos in July
Clear-sky midday UV in July peaks around 10 (very high — sun protection essential). The full-year curve, shaded by WHO exposure level, is below.
Under clear skies, the midday UV index in San Marcos peaks around August 11 at about 11 (extreme) — sunscreen, a hat and midday shade are essential. It bottoms out near December 20 at about 4 (moderate).
The index reaches 3 or more — the level where the WHO recommends sun protection — every month of the year.
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| UV index (midday) | 4 | 6 | 7 | 10 | 10 | 10 | 10 | 11 | 9 | 6 | 5 | 4 |
| Level | Moderate | High | High | Very high | Extreme | Extreme | Extreme | Extreme | Very high | High | Moderate | Moderate |
| UV index (midday) | Level | |
|---|---|---|
| Jan | 4 | Moderate |
| Feb | 6 | High |
| Mar | 7 | High |
| Apr | 10 | Very high |
| May | 10 | Extreme |
| Jun | 10 | Extreme |
| Jul | 10 | Extreme |
| Aug | 11 | Extreme |
| Sep | 9 | Very high |
| Oct | 6 | High |
| Nov | 5 | Moderate |
| Dec | 4 | Moderate |
Air quality in San Marcos in July
Average fine-particle pollution (PM2.5) through the year — so you can see where July falls, not just the annual average.
Air quality in San Marcos is worst in July — around 17 µg/m³ PM2.5 (moderate), about 2.9× the cleanest month (December, 6 µg/m³).
Modeled monthly averages (CAMS reanalysis, 2015–2024).
| Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| PM2.5 (µg/m³) | 6 | 7 | 8 | 9 | 14 | 14 | 17 | 12 | 10 | 6 | 6 | 6 |
| Level | Good | Good | Good | Good | Moderate | Moderate | Moderate | Good | Good | Good | Good | Good |
| PM2.5 (µg/m³) | Level | |
|---|---|---|
| Jan | 6 | Good |
| Feb | 7 | Good |
| Mar | 8 | Good |
| Apr | 9 | Good |
| May | 14 | Moderate |
| Jun | 14 | Moderate |
| Jul | 17 | Moderate |
| Aug | 12 | Good |
| Sep | 10 | Good |
| Oct | 6 | Good |
| Nov | 6 | Good |
| Dec | 6 | Good |
Where is San Marcos?
San Marcos sits at 29.9°N, 97.9°W, 617 ft above sea level, in United States. The nearest listed city is Kyle, 8.1 mi away.
Topography around San Marcos
How much the land rises and falls, and what covers it, within 2, 10 and 50 miles of San Marcos.
Within 2 miles, the terrain around San Marcos has only modest variations in elevation — a maximum elevation change of 289 ft around an average of 643 ft above sea level; within 10 miles, only modest variations in elevation — a maximum elevation change of 751 ft; within 50 miles, significant variations in elevation — a maximum elevation change of 1,814 ft.
The land around San Marcos is covered by trees (42%), artificial surfaces (31%) and grassland (23%) within 2 miles, trees (41%) and grassland (39%) within 10 miles, and trees (48%) and grassland (42%) within 50 miles.
United States travel facts
- Power plugs
- Type A / B
- 120 V · 60 Hz
- Prices
- ≈ 100% of US
- price level, 2025
- GDP per capita
- $90,027
- 2025
- Happiness
- 6.8 / 10
- World Happiness, 2025
- Safe drinking water
- 98%
- of population, 2024
- Homicide rate
- 5.8
- per 100k, 2023
- Road deaths
- 12.7
- per 100k/yr, 2019
- Income group
- High
- World Bank
- Religion
Sources: World Bank, US State Department, World Happiness Report, WHO/UNICEF, EF EPI, CIA World Factbook.
Data sources
Temperature, precipitation, cloud, humidity, wind and solar figures are a 1991–2020 climatology for San Marcos (29.8833°, -97.9414°, elevation 617 ft), computed from hourly ERA5 reanalysis — contains modified Copernicus Climate Change Service information. Sun figures are astronomical calculations, not observations. City data © GeoNames, CC BY 4.0. Map outlines from Natural Earth (public domain); interactive map © Google. UV index is derived from CAMS (Copernicus Atmosphere Monitoring Service) clear-sky UV data — contains modified Copernicus Atmosphere Monitoring Service information. Monthly air-quality (PM2.5) seasonality is from the CAMS EAC4 reanalysis (Copernicus Atmosphere Monitoring Service), scaled to the WHO annual mean where available. Topography is sampled from the Copernicus DEM GLO-90 elevation model (© ESA/Airbus) and ESA WorldCover 2021 land cover (CC BY 4.0).