San Marcos weather in August: San Marcos, Texas: normal highs, lows, rain and records for August
San Marcos in August has a normal high of 97°F and a normal low of 74°F, a daily mean of 85°F, falling from 98°F on the 1st to 94°F by the 31st. Measurable precipitation falls on 5 days in a normal August, 2.60 inches in all. (NOAA 1991-2020 normals)
In metric: a normal high of 36°C and low of 23°C, 66 mm of precipitation in August.
- NOAA stationSan Marcos
- Station IDUSC00417983
- Location29.88°N 97.95°W
- Elevation665 ft (203 m)
- Population74,316
- Jan 62° 39°
- Feb 67° 42°
- Mar 73° 50°
- Apr 80° 56°
- May 86° 65°
- Jun 92° 72°
- Jul 96° 73°
- Aug 97° 74°
- Sep 91° 69°
- Oct 82° 58°
- Nov 72° 48°
- Dec 64° 41°
Each month: normal high (large) and low, °F. Fill: the month's normal mean, colder blue to hotter red.
How warm is San Marcos in August?
The normal high is 97°F and the normal low 74°F, for a daily mean of 85.2°F. August is 0.7°F warmer than July and 5.7°F warmer than September. August is the warmest month of the year in San Marcos and the 8th wettest. Across the month the normal high falls 4°F, from 98°F on August 1 to 94°F on August 31. From one year to the next August's mean temperature typically moves about 2.2°F either way (NOAA's standard deviation), so roughly two Augusts in three average between 83°F and 87°F.
Bars above: each day's normal high to low. Columns below: the chance of 0.01 inch or more of precipitation that day, on a scale of 0 to 100% (highest 22%).
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in |
|---|---|---|---|---|
| August 1 | 98°F | 74°F | 14% | 8% |
| August 8 | 98°F | 74°F | 14% | 8% |
| August 15 | 97°F | 74°F | 16% | 10% |
| August 22 | 96°F | 74°F | 19% | 12% |
| August 31 | 94°F | 72°F | 22% | 15% |
Every day of August: normal high, low and chance of precipitation (warmest afternoon August 7, coldest night August 31)
| Day | High | Low | Chance of 0.01 in | Chance of 0.10 in | Daylight |
|---|---|---|---|---|---|
| August 1 | 98°F | 74°F | 14% | 8% | 13 h 40 min |
| August 2 | 98°F | 74°F | 14% | 8% | 13 h 30 min |
| August 3 | 98°F | 74°F | 14% | 8% | 13 h 30 min |
| August 4 | 98°F | 74°F | 14% | 8% | 13 h 30 min |
| August 5 | 98°F | 74°F | 14% | 8% | 13 h 30 min |
| August 6 | 98°F | 74°F | 14% | 8% | 13 h 30 min |
| August 7 | 98°F | 74°F | 14% | 8% | 13 h 30 min |
| August 8 | 98°F | 74°F | 14% | 8% | 13 h 30 min |
| August 9 | 98°F | 74°F | 14% | 9% | 13 h 20 min |
| August 10 | 98°F | 74°F | 15% | 9% | 13 h 20 min |
| August 11 | 98°F | 74°F | 15% | 9% | 13 h 20 min |
| August 12 | 98°F | 74°F | 15% | 9% | 13 h 20 min |
| August 13 | 98°F | 74°F | 15% | 9% | 13 h 20 min |
| August 14 | 98°F | 74°F | 16% | 10% | 13 h 20 min |
| August 15 | 97°F | 74°F | 16% | 10% | 13 h 20 min |
| August 16 | 97°F | 74°F | 16% | 10% | 13 h 10 min |
| August 17 | 97°F | 74°F | 17% | 10% | 13 h 10 min |
| August 18 | 97°F | 74°F | 17% | 11% | 13 h 10 min |
| August 19 | 97°F | 74°F | 17% | 11% | 13 h 10 min |
| August 20 | 97°F | 74°F | 18% | 11% | 13 h 10 min |
| August 21 | 97°F | 74°F | 18% | 12% | 13 h 10 min |
| August 22 | 96°F | 74°F | 19% | 12% | 13 h |
| August 23 | 96°F | 74°F | 19% | 12% | 13 h |
| August 24 | 96°F | 73°F | 19% | 12% | 13 h |
| August 25 | 96°F | 73°F | 20% | 13% | 13 h |
| August 26 | 96°F | 73°F | 20% | 13% | 13 h |
| August 27 | 95°F | 73°F | 20% | 13% | 13 h |
| August 28 | 95°F | 73°F | 21% | 14% | 12 h 50 min |
| August 29 | 95°F | 73°F | 21% | 14% | 12 h 50 min |
| August 30 | 95°F | 73°F | 22% | 14% | 12 h 50 min |
| August 31 | 94°F | 72°F | 22% | 15% | 12 h 50 min |
- Normal high
- 97°FAugust average
- Normal low
- 74°FAugust average
- Precipitation
- 2.60 inmonth total
- Days with precipitation
- 50.01 inch or more
- Days at 90°F or more
- 29
- Daylight
- 13 h 40 min to 12 h 50 minAugust 1 to August 31
- Days at 70°F or more
- 31
- Days at 80°F or more
- 31
- Sunshine
- 87%of clear-sky sunlight (NASA)
Source: NOAA NCEI 1991-2020 daily normals, station USC00417983; monthly normals. Daylight is computed from the place's latitude with NOAA's solar equations.
Does it rain in San Marcos in August?
On a given August day the chance of 0.01 inch or more is 17% on average, highest around August 31 (22%). In all, 2.60 in falls on 5 days of a normal August, 1 of them with an inch or more.
In a normal August in San Marcos, 29 days reach 90°F.
Source: NOAA NCEI 1991-2020 daily and monthly normals, station USC00417983.
What are the records for August in San Marcos?
The warmest August temperature on this station's record (since 1895) is 111°F, on August 23, 1917; the coldest is 50°F, on August 29, 2010. The wettest August brought 12.50 in (2017).
The August mean against the 1991-2020 normal of 85.2°F: 2021 84.1°F (−1.1), 2022 86.4°F (+1.2), 2023 90.6°F (+5.4), 2024 85.7°F (+0.5), 2025 87.1°F (+1.9), 2026 88.7°F (+3.5). 5 of 6 ran warmer than normal.
| August | Mean | Against normal | Precip. |
|---|---|---|---|
| 2021 | 84.1°F | −1.1°F | 2.83 in |
| 2022 | 86.4°F | +1.2°F | 1.95 in |
| 2023 | 90.6°F | +5.4°F | 0.25 in |
| 2024 | 85.7°F | +0.5°F | 3.28 in |
| 2025 | 87.1°F | +1.9°F | 0.65 in |
| 2026 | 88.7°F | +3.5°F | 0.57 in |
Source: records: ACIS, station USC00417983; recent months: ACIS, station USC00417983. Records and recent months use complete months only.
How does August in San Marcos compare across Texas?
Across the 321 places PlainClimate covers in Texas, August normal highs run from 87°F in Marfa to 101°F in Del Rio; San Marcos's is 97°F.
Source: NOAA NCEI 1991-2020 monthly normals for every station in the state.